WO2018041921A1

WO2018041921A1 - Mixing device for the production of a liquid nucleic acid composition

Info

Publication number: WO2018041921A1
Application number: PCT/EP2017/071815
Authority: WO
Inventors: Michael Sonntag; Bernd HELD; Arne SALZ-SIEGWALT; Isabel REICHERT; Axel MÜLLER
Original assignee: Curevac Ag
Priority date: 2016-08-31
Filing date: 2017-08-30
Publication date: 2018-03-08

Abstract

The present invention relates to a mixing device for the production of a liquid nucleic acid composition, a hose routing comprising such mixing device, a mixing array comprising a plurality of such mixing devices and a method 5 for the production of a liquid nucleic acid composition. Further, several uses described herein are part of the present invention. The liquid nucleic acid composition may comprise at least a nanoparticle comprising a nucleic acid and a complexation partner. The mixing device comprises a first inlet tube for a first component comprising a liquid nucleic acid solution, a second inlet tube for a second component, a connecting element, and an outlet tube. The connecting element is configured to connect the first inlet tube and the second inlet tube to the outlet 0 tube. The outlet tube comprises a swirling element configured to introduce a swirling of the first component and/or the second component in the outlet tube to allow a mixing of the first component and the second component to produce the liquid nucleic acid composition.

Description

Mixing device for the production of a liquid nucleic acid composition

Field of the invention

The present invention relates to a mixing device for the production of a liquid nucleic acid composition, a hose routing comprising such mixing device, a mixing array comprising a plurality of such mixing devices and a method for the production of a liquid nucleic acid composition. Further, several uses described herein are part of the present invention. The liquid nucleic acid composition may comprise at least a nanoparticle comprising a liquid nucleic acid and a complexation partner.

Background of the invention

Therapeutic nucleic acids including RNA represent an emerging class of drugs. RNA-based therapeutics include mRNA molecules encoding antigens for use as vaccines (Fotin-Mleczek et al. 2012. J. Gene Med. 14(6):428- 439). In addition, it is envisioned to use RNA molecules for replacement therapies, e.g. providing missing proteins such as growth factors or enzymes to patients (Kariko et al., 2012. Mol. Ther. 20(5):948-953; Kormann et al., 2012. Nat. Biotechnol. 29(2):154-157). Furthermore, the therapeutic use of noncoding immunostimulatory RNA molecules (e.g. WO2009/095226A2) and other noncoding RNAs such as microRNAs and long noncoding RNAs (Esteller, 2011. Nat. Rev. Genet. 12(12):861-74) or RNAs suitable for genome editing (e.g. CRISPR/Cas9 guide RNAs) is considered.

It has been found that the successful in vivo delivery of nucleic acids including RNA depends on the formulation of the active molecules into dosage forms suitable for the therapeutic application. In this context, particularly, the complexation of nucleic acids with polycatonic compounds, which results in nanoparticles, has been found to improve the in vivo delivery of nucleic acids, especially of RNA.

Different nucleic acid-comprising nanoparticles and methods for the preparation thereof have been described in the art, for example in the documents listed in the following. WO2010/037539A1 describes immunostimulatory compositions comprising a) an adjuvant component, comprising or consisting of at least one (m)RNA, complexed with a cationic or polycationic compound (protamine), and b) at least one free mRNA, encoding at least one therapeutically active protein, antigen, allergen and/or antibody, wherein the immunostimulatory composition is capable to elicit or enhance an innate and optionally an adaptive immune response in a mammal. The production of nanoparticles from RNA and protamine is described to comprise mixing.

WO2009/144230A1, WO2012/094574, and Yang and colleagues (Liu, Zhenzhen, et al., International journal of nanomedicine 10 (2015): 2735) describe RNA-comprising nanoparticles of defined average size, a pharmaceutical composition containing said nanoparticles and to a method of producing the same. The production of nanoparticles from RNA and protamine is described to comprise mixing conducted by pipette or vortexing. Typically, as highlighted above, only relatively small volumes (<1 mL) are prepared on a laboratory scale by simply adding nucleic acid (RNA) to a solution of cationic or polycationic compounds (or vice versa) with subsequent mixing by repeated inversion or pipetting.

Under such circumstances, it is virtually impossible to standardize the reaction conditions, which results in the variability of the physical characteristics of the produced nanoparticles, e.g. to a batch -to- batch variation. Moreover, said conventional bulk techniques may face limitations including poor reproducibility, polydisperse particle size distribution and batch-to-batch variation with respect to physicochemical properties of the nanoparticle. Such variability is further exacerbated by attempts to scale-up reaction volumes for pre-clinical or clinical studies, and further market delivery, where differences in physical characteristics are not acceptable.

Therefore, suitable devices for the formulation of nucleic acid nanoparticles are needed and have been described in the art, for example in the documents listed in the following.

A pneumatic mixing device enabling the production of large volumes of non-viral gene therapy formulations was reported (Davies et al., 2010. Biotechniques 49(3):666-668). This mixing device uses compressed air to depress the plunger of a disposable dual barrel polypropylene syringe containing plasmid DNA and lipid/polymer in separate compartments. Activation of the device initiates mixing of the components by simultaneous extrusion of the two reagents through a static mixer device. WO1999/040771 describes concurrent flow mixing methods and apparatuses using e.g. static or dynamic mixers that could be adapted for the preparation of gene therapy vector and vehicle compositions of controlled particle size for condensate complexes. However, actual testing was only carried out on a microliter scale

A method for the preparation of siRNA-containing lipid nanoparticles by controlled microfluidic formulation was described by Chen et al., J. Am. Chem. Soc. 2012. 134(16):6948-6951. The formulation method is based on stepwise ethanol dilution to produce siRNA lipid nanoparticles on a microliter scale.

Summary of the invention

As outlined above, several problems are associated with common devices and methods and further improvements of the state-of-the-art devices and methods are urgently needed. Thus, there is a need for providing an improved mixing device for a production of a liquid nucleic acid composition which allows the production of such liquid nucleic acid composition on large scale. Particularly, there is a need for providing an improved mixing device for the production of a pharmaceutical liquid nucleic acid composition, suitably, for use as a medicament.

This problem is solved by the subject-matter of the independent claims, wherein further embodiments are incorporated in the dependent claims. It should be noted that the features of the invention described in the following apply equally to the mixing device for the production of a liquid nucleic acid composition, the hose routing comprising such mixing device, the mixing array comprising a plurality of such mixing devices, the method for the production of a liquid nucleic acid composition and to the uses described herein. In a first aspect, the present invention is directed to a mixing device for the production of a liquid nucleic acid composition. The mixing device comprises:

a first inlet tube for a first component comprising a nucleic acid,

a second inlet tube for a second component,

a connecting element, and

- an outlet tube.

The connecting element is configured to connect the first inlet tube and the second inlet tube to the outlet tube. The outlet tube comprises a bend or a baffle as swirling element configured to introduce a swirling of the first component and the second component in the outlet tube to allow a mixing of the first component and the second component to produce the liquid nucleic acid composition. The bend bends between 45° and 135° relative to the outlet tube.

It was surprisingly found that the introduction of such swirling element in the outlet tube and optionally also in at least one of the inlet tubes leads to a mixing or at least an improved mixing of the two components. The mixing is caused by the swirling element in form of a bend, which bends between 45° and 135° relative to the respective tube and/or a baffle. The swirling element creates a swirling of the components, which generates a rotation of the components in the tube, and which eventually causes the mixing of the components.

Advantageously, the introduction of a swirling element in the outlet led to a strongly improved mixing of the first component and the second component (consistent higher degree of homogeneity, faster mixing time/blend time, generation nucleic acid nanoparticles of a monodisperse particle size).

Thereby, the present invention relates to a mixing device suitable for a production of a liquid nucleic acid composition on large flexible scale. In the context of the invention, the term "large scale" refers to an amount of compound, which summarily comprises a nucleic acid in an amount of lg or more, preferably in an amount of 5g and more, more preferred in an amount of lOg or more, even more preferred in an amount of 300g or more. The present invention may also relate to a mixing device suitable for a production of a liquid nucleic acid composition on flexible or even small scale. The term "small scale" may refer to an amount smaller than above defined "large scale" amounts. "Flexible" may mean that the amount can be adapted to a desired amount lying e.g. within above defined amounts.

In an embodiment, the first component is liquid, wherein the liquid first component comprises at least one nucleic acid. The nucleic acid may be any type of DNA or RNA. Preferably, the nucleic acid is RNA, even more preferably mRNA. Preferably, the RNA is a purified RNA. Preferably, the RNA is a GMP-grade/pharmaceutical grade RNA. In an embodiment, the second component is also liquid. In an embodiment, the second component comprises a complexation partner. The complexation partner may be cationic or polycationic. The complexation partner may comprise protamine. In an embodiment, the liquid nucleic acid composition comprises at least a nanoparticle comprising the nucleic acid of the first component and a complexation partner of the second component.

The mixing device according to the present invention may further be suitable for a production under regulated conditions (GMP) suitable for pharmaceutical applications. The mixing device may allow a continuous production of a liquid nucleic acid composition comprising e.g. a nanoparticle comprising RNA and e.g. a cationic or polycationic complexation partner. In the context of the invention, the term RNA is used to indicate any type of ribonucleic acid. The mixing device may also be suitable for parallelized high throughput (HT) production and/or screening of, preferably, different nanoparticle comprising compositions (e.g., compositions of protamine- complexed nanoparticles, peptide polymer complexed nanoparticles, lipid nanoparticles (LNP)). The swirling element may be a bend, a baffle and/or any other constructive element of the respective tube suitable to introduce a swirling of the first component and/or the second component in the respective inlet tube and/or the outlet tube to allow a mixing of the first component and the second component to produce the liquid nucleic acid composition. In an embodiment, the first inlet tube and the second inlet tube each comprises a swirling element as described above. In an embodiment, both inlet tubes and the outlet tube each comprise such swirling element. In another embodiment, only the outlet tube comprises such swirling element.

In an embodiment, the swirling element is a bend. The bend bends between 80° and 100° relative to the respective tube. In an embodiment, the bend comprises at least two curves. The at least two curves may be antidromic curved. In an embodiment, the bend has an S-shape or Z-shape. In an embodiment, the bend lies in the plane of the respective tube. In another embodiment, the bend protrudes out of the plane of the respective tube. The bend may protrude essentially perpendicular out of the plane of the respective tube.

In an embodiment, the connecting element is static, which means not moving. In an embodiment, the connecting element has a T-shape or a Y-shape. Such static elements are systems, in which the mixing process is typically initiated by using the hydrodynamic energy of a fluid (liquid / gas) passing through a cavity, such as a pipe or canal, with fixed fittings. Such static connecting element is preferably a kind of mixer that does not rely on mechanical agitation, shaking or stirring by a mechanical device in the mixer. Rather, it relies on static elements, such as walls, channels, capillaries, barriers, offset plates or protrusions such as rods or nubs, or the like, any of which may comprise holes or openings, or be offset from one another, or the like, to direct the flow path in a way to provide flow turbulence and mixing of the solutions/components to be mixed as they proceed through the mixer. In the context of the invention, mixing is further improved by the swirling element as defined above. The flow rate and pressure is determined by a number of factors, including for example, the flow rate of each solution (first / second component) being introduced, the size and diameter of the connectors (inlet tubes) and the respective inlet and outlet openings, the size and shape of the T-shape or Y-shape connecting element, the volume to surface area ratio of the mixer, the number of flow paths and flow path diversions in the mixer, and the like. In an embodiment, the diameter of the connectors (inlet tubes), and/or the diameter of the Y-shape or T-shape connecting elements, and/or the diameter of the outlet tubes, are from 0.1mm to 20mm. In a preferred embodiment, the diameter of the connectors (inlet tubes), and/or the diameter of the Y-shape or T-shape connecting elements, and/or the diameter of the outlet tubes, are from 1mm to 10mm, preferably from 1mm to 5mm, even more preferably from 2mm to 4mm. In a preferred embodiment, where nucleic acid, preferably RNA, is formulated in an amount of lOg or more, the diameter of the connectors (inlet tubes), and/or the diameter of the Y-shape or T-shape connecting elements, and/or the diameter of the outlet tubes, are approximately 3.2mm. In a preferred embodiment, where nucleic acid, preferably RNA, is formulated in an amount of lOOg or more, the diameter of the connectors (inlet tubes), and/or the diameter of the Y-shape or T-shape connecting elements, and/or the diameter of the outlet tubes, are from 4.8mm to 6.4mm. In a preferred embodiment, where nucleic acid, preferably RNA, is formulated in an amount of 0.9g or less, the diameter of the connectors (inlet tubes), and/or the diameter of the Y-shape or T-shape connecting elements, and/or the diameter of the outlet tubes, are approximately 0.4mm. In an embodiment, the mixing device further comprises a pumping element configured to pump the first component and/or the second component into the connecting element. The pumping element may be configured to pump the first component and the second component with different flow rates. In an embodiment, the pumping element comprises at least a peristaltic pump. In an embodiment, the mixing device further comprises a first container configured to contain the first component, a second container configured to contain the second component and/or an outlet container configured to contain the liquid nucleic acid composition. In an embodiment, the mixing device is at least partially manufactured out of one of a group comprising silicone, PET, and stainless steel. In an embodiment, a flow rate of the nucleic acid composition is between 200 and lOOOml/min and in particular between 400 and 800ml/min. In an embodiment, a blend time for the mixing of the first component and the second component up to at least 70% homogeneity is between 0.05 and Is, preferably between 0.1 and 0.5s and more preferably between 0.1s and 0.15s. In a second aspect, the present invention is directed to a hose routing comprising a mixing device as described above. The mixing device as described above may be integrated into a table element. The mixing device and its tubes may be placed into the table element to allow scalable and efficient nucleic acid nanoparticle formulation. The advantage of such a design is that the formulation can be performed in a regulated environment (e.g., GMP- grade tubing system can be used as single use element and GMP-grade containers can be used as single use elements).

The hose routing may be constructed via 3D printing. In an embodiment, the tube that is placed into the hose routing is made of GMP-compatible materials. In an embodiment, the tube is a silicone or a PET tube, most preferably as single-used materials. In another embodiment, the tube is manufactured using other materials, e.g. stainless steel. In an embodiment, the tube is a solid tube, e.g. manufactured from plastic materials. Preferably, the used materials are GMP-compatible materials. In a third aspect, the present invention is directed to a mixing array comprising a plurality of mixing devices as described above. The mixing array may comprise 6, 12, 24, 48 or 96 mixing devices. The mixing array may be configured to produce different nucleic acid compositions simultaneously or, in other words, to allow for a parallelized formulation of (different) nucleic acid (e.g., RNA, DNA) nanoparticle comprising solutions. The different nucleic acid compositions may differ from each other in the first component and/or the second component. As the system may allow a parallel formulation of different nucleic acid nanoparticle comprising solutions, it may be particularly suitable for screening approaches or a parallel production of different nucleic acid nanoparticle comprising solutions under GMP conditions.

In a fourth aspect, the present invention is directed to a method for the production of a liquid nucleic acid composition. The method comprises the following steps:

a) providing a first component of the composition by a first inlet tube,

wherein the first component comprises a nucleic acid,

b) providing a second component of the composition by a second inlet tube,

c) guiding the first component and the second component to an outlet tube, and

d) introducing a swirling of the first component and the second component in the outlet tube by means of a bend or a baffle to allow a mixing of the first component and the second component to produce the liquid nucleic acid composition. The bend bends between 45° and 135° relative to the outlet tube.

In an embodiment, the liquid nucleic acid composition comprises at least a nanoparticle comprising the nucleic acid of the first component and a complexation partner of the second component. Thereby, the method according to the present invention may be suitable for a large scale and preferably also continuous production of a liquid composition comprising a nanoparticle comprising nucleic acid (e.g. RNA) as a first component and e.g. a cationic or polycationic complexation partner as second component. The present method may be further performed in a parallelized and/or high-throughput manner.

The nucleic acid may be RNA and in particular mRNA (messenger RNA). In the context of the invention, the term RNA is used to indicate any type of ribonucleic acid. Examples of RNA, which can be used in the method of the present invention are disclosed, e.g. in WO2008/077592A1, WO2009/095226A2, WO2010/037539 and WO2011/026641A1, which are all incorporated herein by reference.

The nanoparticle may have a particle size between 50nm and 200nm, and in particular between 50nm and 150nm.

In embodiments where the nanoparticles are lipid nanoparticles, the nanoparticle may have a particle size of from about 30nm to about 150nm, from about 50nm to about 150nm, preferably from about 70nm to about lOOnm.

In embodiments where the nanoparticle is formed by a polymeric carrier molecule as defined herein, the nanoparticle may have a particle size of from about 30nm to about 800nm, from about 50nm to about 300nm, preferably from about 60nm to about 200nm . "Particle size" as used herein has to be understood as the hydrodynamic diameter of a nanoparticle as defined herein determined by dynamic laser scattering.

In an embodiment, the first component comprises nucleic acid, preferably RNA in a concentration of from 0.1 to 20g/L, preferably from 0.5 to lOg/L, and more preferably from 0.5 to 7g/L. In an embodiment, the second component e.g. a complexation partner comprises a cationic or polycationic compound in a concentration in a range from 0.05 to lO.OOg/L, preferably from 0.10 to 5.00g/L or, more preferably, from 0.10 to l.OOg/L. In an embodiment, the complexation partner is protamine. In a fifth aspect, the present invention is directed to a use of a mixing device, hose routing or mixing array as described above in a method as described above.

In a sixth aspect, the present invention is directed to a use of a mixing device, hose routing or mixing array as described above in a method for producing a medicament or a vaccine containing the liquid nucleic acid composition. The mixing device may be a single device for large scale production.

In a seventh aspect, the present invention is directed to a use of a mixing device, hose routing or mixing array as described above in a method for high throughput production and/or screening of liquid nucleic acid compositions. The high throughput production may be a parallelized high-throughput production suitable for a GMP compatible production of personalized/individualized nucleic acid therapeutics, e.g. RNA therapeutics.

In summary, flexibly scalable devices and methods for the economical, controllable, reproducible, continuous, GMP- and HT-compatible (that is, production of different formulations in parallel) nucleic acid (e.g., DNA, RNA) nanoparticle production are presented. Especially, for pre-clinical and clinical studies, and eventually a market delivery of a medicament based on a nucleic acid-comprising compound and/or nanoparticles, a GMP-compatible production device is presented to allow a reproducible and reliable production of nucleic acid-comprising compound and/or nanoparticles, which are to be obtained with a consistently good quality (i.e. constant particles sizes and polydispersity) in the large scale production thereof. Moreover, in the context of HT-compatible screening approaches or HT-compatible and GMP-compatible production of nucleic acid based pharmaceuticals, e.g. RNA based pharmaceuticals (e.g., for a production of personalized pharmaceuticals), devices and methods are presented that can be down-scaled such that small amounts of the nucleic acid nanoparticles can be produced, preferably also in a parallelized manner.

It shall be understood that the mixing device for the production of a liquid nucleic acid composition, the hose routing comprising such mixing device, the mixing array comprising a plurality of such mixing devices, the method for the production of a liquid nucleic acid composition and to the uses according to the independent claims have similar and/or identical preferred embodiments, in particular, as defined in the dependent claims. It shall be understood further that a preferred embodiment of the invention can also be any combination of the dependent claims with the respective independent claim.

These and other aspects of the present invention will become apparent from and be elucidated with reference to the embodiments described hereinafter. Brief description of the drawings

The Figures shown in the following are merely illustrative and shall describe the present invention in a further way. These figures shall not be construed to limit the present invention thereto.

Figure 1 shows a schematic view of a continuously operating mixing device according to

Example 3.

Figure 2 shows a computational model of a mixing device used for a CFD analysis according to Example 4.

Figure 3 shows an exemplary result of the CFD analysis performed according to Example 4.

Figure 4 shows an exemplary result of a CFD analysis performed according to Example 5.

Figure 5 shows models of static mixing devices.

Figure 6 shows an exemplary result of a CFD analysis performed according to Example 6.

For the simulation, a mixing device according to Figure 5A was used. Figure 7 shows another exemplary result of the CFD analysis performed according to

Example 6. For the simulation, a mixing device according to Figure 5B was used. Figure 8 shows an exemplary result of the CFD analysis performed according to Example 6.

For the simulation, a mixing device according to Figure 5C was used. Figure 9 shows an exemplary result of the CFD analysis performed according to Example 6.

For the simulation, a mixing device according to Figure 5D was used.

Figure 10 shows an exemplary illustration of a hose routing.

Figure 11 shows a top view of an exemplary arrangement of a hose routing table.

Figure 12 shows an example of miniaturized mixing devices.

Figure 13 shows an example of a multi-array arrangement of mixing devices suitable for high throughput (HT) applications.

Figure 14 shows the Z-average of RNA nanoparticles using the setup according to Figure 11.

The experiment was performed as described in Example 10.

Figure 15 shows the PDI values of RNA nanoparticles using the setup according to Figure 11.

The experiment was performed as described in Example 10.

Figure 16 shows Turbidity values of RNA nanoparticles using the setup according to Figure

11. The experiment was performed as described in Example 10.

Definitions

For the sake of clarity and readability the following definitions are provided. Any technical feature mentioned for these definitions may be read on each and every embodiment of the invention. Additional definitions and explanations may be specifically provided in the context of these embodiments.

The first component:

In the context of the present invention, the first component may be liquid, comprising nucleic acids. In this context, nucleic acids may comprise any type of DNA (e.g., plasmid DNA, chromosomal DNA, linear DNA fragments, viral DNA, bacterial DNA, single stranded DNA, double stranded DNA) or any type of RNA (long-chain RNA, a coding RNA, a non-coding RNA, a single stranded RNA (ssRNA), a double stranded RNA (dsRNA), a linear RNA (linRNA), a circular RNA (circRNA), a messenger RNA (mRNA), an RNA oligonucleotide, a small interfering RNA (siRNA), a small activating RNA (saRNA), a small hairpin RNA (shRNA), an antisense RNA (asRNA), a CRISPR/Cas9 guide RNA (small guide RNA, sgRNA), a riboswitch, an immunostimulating RNA (isRNA), a ribozyme, an aptamer, a ribosomal RNA (rRNA), a transfer RNA (tRNA), a viral RNA (vRNA), a retroviral RNA, or a replicon RNA, a small nuclear RNA (snRNA), a small nucleolar RNA (snoRNA), a microRNA (miRNA), and a Piwi- interacting RNA (piRNA)).

Suitably, the nucleic acid is RNA, preferably in vitro transcribed RNA, more preferably a GMP-grade RNA (GMP = good manufacturing practice). GMP-grade RNA is produced using a manufacturing process approved by regulatory authorities, implementing various quality controls on DNA level and RNA level as described in detail in WO2016/180430A1. With respect to the specific manufacturing process, the disclosure of WO2016/180430A1 is incorporated herewith by reference.

The term "purified RNA" means that the RNA has a higher purity after purification than the starting material and that the amount of byproducts or reagents of the in vitro transcription is decreased after purification. Preferably, the RNA has a degree of purity of more than 70%, in particular more than 80%, very particularly more than 90% and most favourably 99% or more. The degree of purity may for example be determined by an analytical HPLC, wherein the percentage provided above corresponds to the ratio between the area of the peak for the target RNA and the total area of all peaks representing the by-products. Preferably, the RNA is purified by a HPLC procedure as described in WO2008/077592A1. RNA may also be purified by tangential flow filtration (WO2016/193206A1 or WO2014/152966A1), oligo d(T) purification (WO2014/152031A1), ion exchange chromatography (WO2014/144767A1), hydroxyapatite chromatography (WO2014/140211A1) or core bead flow-through chromatography (WO2014/140211A1), or combinations thereof. With respect to the specific methods, the disclosures of WO2008/077592A1, WO2016/193206A1, WO2014/152031A1, WO2014/144767A1, WO2014/152966A1, and WO2014/140211A1 are incorporated herewith by reference.

Preferably, the nucleic acid is RNA, more preferably a coding RNA. Even more preferably, the RNA is a (linear) single-stranded RNA, even more preferably an mRNA.

In an embodiment, the RNA is a modified mRNA, wherein modifications are selected from chemical modifications (backbone modifications, sugar modifications, base modifications), lipid modifications, 5'-end modifications (e.g., 5' cap structure), coding sequence modifications (G/C enriched, GC maximized, GC optimized e.g. according to WO2002/098443 codon optimized, CAI adapted, C-maximized e.g. according to WO2015/062738), 3'-end modifications (e.g. poly(A)sequence, poly(C)sequence, histone-stem-loop (e.g. according to WO2012/019780)), addition of (preferably heterologous) untranslated elements (UTR) etc.

In an embodiment, the RNA is a non-coding RNA, preferably an immune stimulatory RNA. In embodiments, the immune stimulatory RNA is selected from the RNA sequences according to SEQ ID NOs: 1 to 5 or from a sequence having at least 60%, 70%, 80%, 90%, or even 95% sequence identity to any of these sequences.

In a preferred embodiment, the immune stimulatory RNA is selected from SEQ ID NO 3 or SEQ ID NO 4. The first component comprising a nucleic acid may comprise exactly one (type of) nucleic acid molecule, particularly on type of RNA molecule, or a mixture of two or more different (types of) nucleic acid molecules, such as, for example, two, three, four, five, six etc. different (types of) nucleic acid molecules, wherein a plurality of each (type of) nucleic acid molecule is preferably present in the first component. Preferably, the first component comprises from 1 to 20 different nucleic acid molecules, further preferred from 1 to 10 different nucleic acid molecules, further preferred from 1 to 6, and still further preferred 1, 2, 3, 4, 5 or 6 different nucleic acid molecules.

In an embodiment, the first component comprises more than one type of RNA, wherein the RNA molecules differ in their respective coding regions and, optionally, further structural elements. Preferably, the first component comprises 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 different RNA molecules, each of which encodes a distinct peptide or protein preferably an antigen (e.g. tumor, viral, bacterial) or therapeutic protein. Especially preferably, the first component comprises one type of RNA, even more preferably one type of mRNA (that is, an mRNA encoding distinct protein(s) or protein construct(s)).

Preferably, the first component comprises water as a solvent. Additionally, the first component may comprise at least one solvent miscible with water. Examples of such water-miscible solvents are known in the art. Preferred examples of additional solvents are alcohols, such as, e.g. ethanol, etc., DMSO, and the like. Especially preferred, the additional solvent is pharmaceutically acceptable. Examples of pharmaceutically acceptable solvents are, e.g. ethanol, etc.

Preferably, the first component is an aqueous solution of a nucleic acid, particularly of RNA and, optionally, at least one further component. In a preferred embodiment, the nucleic acid, particularly the RNA, is present in the first component in its free form, i.e. as 'naked' nucleic acid, e.g. 'naked' DNA or 'naked' RNA. In another embodiment, the first component additionally comprises at least one further compound selected from a salt or a lyoprotectant.

In an embodiment, the first component has a viscosity of from 0.5-10mm²/s, preferably from l-5mm²/s, more preferably from l-3mm²/s. In a preferred embodiment, the first component comprising nucleic acid, preferably RNA, has a viscosity of approximately 2.39mm²/s.

In a preferred embodiment, the first component comprises naked RNA in a concentration of from 0.1 to 20g/L, preferably from 0.5 to lOg/L, more preferably from 0.5 to 7g/L, more preferably of from 0.5 to 2g/L and most preferably of from 0.5 to l.Og/L. More preferably, the first component comprises the at least one RNA as defined herein in a concentration as defined above.

The second component:

In the context of the present invention, the second component may comprise at least one cationic or polycationic compound, and is preferably liquid. In the context of the invention, the term "cationic or polycationic compound" is used for a compound, preferably an oligomeric or polymeric compound, comprising one to numerous cationic functions (i.e. positive charges). Such compounds are known in the art, where they are sometimes also referred to as "polycationic molecules" or "polycationic polymers". Examples of cationic or polycationic compounds comprise cationic or polycationic peptides or polypeptides, cationic or polycationic proteins, cationic or polycationic polyamino acids, cationic or polycationic carbohydrates, cationic or polycationic synthetic polymers, cationic or polycationic small synthetic organic molecules, inorganic multivalent cations, cationic lipids, lipidoids, ionizable lipids and the like. Preferred examples of cationic or polycationic compounds which can be used in the method of the present invention are disclosed, e.g. in WO2008/077592A1, WO2009/095226A2, WO2010/037539, WO2011/026641A1, which are all incorporated herein by reference.

In an embodiment, the second component comprises at least one cationic or polycationic compound, wherein the at least one cationic or polycationic compound is preferably capable of forming a complex with the nucleic acid, e.g. the DNA or RNA comprised in the first component. More preferably, the at least one cationic or polycationic compound comprised in the second component forms a nanoparticle (e.g., lipid nanoparticle (LNP), protamine nanoparticle, polymer-based nanoparticle) with the nucleic acid, e.g. the DNA or RNA comprised in the first component, wherein the composition, optionally comprises at least one further component, such as, for instance, a lyoprotectant, preferably as defined herein. Preferred cationic or polycationic compounds which may be comprised in the second component include protamine, nucleoline, spermine or spermidine, or other cationic peptides or proteins, such as poly-L-lysine (PLL), poly-arginine, Arg7, Arg8, Arg9, ArglO, Argil, Argl2, H3R9, R9H3, H3R9H3, YSSR9SSY, CR12C, CR12, R12CR12C, WR12CWR12C, CR12CR12CCR12, WR12CCR12W, WR12CCR12CCR12W, (RKH)4, Y(RKH)2R, etc., basic polypeptides, cell penetrating peptides (CPPs), including HIV-binding peptides, HIV-1 Tat (HIV), Tat- derived peptides, Penetratin, VP22 derived or analog peptides, HSV VP22 (Herpes simplex), MAP, KALA or protein transduction domains (PTDs), PpT620, proline-rich peptides, arginine-rich peptides, lysine-rich peptides, MPG- peptide(s), Pep-1, L-oligomers, Calcitonin peptide(s), Antennapedia-derived peptides (particularly from Drosophila antennapedia), pAntp, plsl, FGF, Lactoferrin, Transportan, Buforin-2, Bac715-24, SynB, SynB(l), pVEC, hCT-derived peptides, SAP, or histones.

In a preferred embodiment, the cationic or polycationic compound is protamine.

In other embodiments, the at least one cationic or polycationic compound in the second component may be a cationic or polycationic peptide or protein, which optionally comprises or is additionally modified to comprise at least one -SH moiety. Preferably, the at least one cationic or polycationic compound is selected from cationic peptides having the following sum formula (I):

{(Arg)l;(Lys)m;(His)n;(Orn)o;(Xaa)x>; formula (I) wherein l + m + n + o + x = 3-100, and I, m, n or o independently of each other is any number selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21-30, 31-40, 41-50, 51-60, 61-70, 71-80, 81-90 and 91-100 provided that the overall content of Arg (Arginine), Lys (Lysine), His (Histidine) and Orn (Ornithine) represents at least 10% of all amino acids of the oligopeptide; and Xaa is any amino acid selected from native (= naturally occurring) or non-native amino acids except of Arg, Lys, His or Orn; and x is any number selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21-30, 31-40, 41-50, 51-60, 61-70, 71-80, 81-90, provided, that the overall content of Xaa does not exceed 90 % of all amino acids of the oligopeptide. Any of amino acids Arg, Lys, His, Orn and Xaa may be positioned at any place of the peptide. In this context, cationic peptides or proteins in the range of 7-30 amino acids are particular preferred. With respect to cationic or polycationic proteins or peptides, the disclosure of WO2009/030481 is incorporated herein by reference.

Further, the cationic or polycationic peptide or protein, when defined according to formula {(Arg)l;(Lys)m;(His)n;(Orn)o;(Xaa)x} (formula (I)) as shown above and which comprises or is additionally modified to comprise at least one -SH moiety, facilitating the formation of polymers, may be, without being restricted thereto, selected from subformula (la):

{(Arg)l;(Lys)m;(His)n;(Orn)o;(Xaa')x (Cys)y> subformula (la) wherein (Arg)l;(Lys)m;(His)n;(Orn)o; and x are as defined herein, Xaa' is any amino acid selected from native (= naturally occurring) or non-native amino acids except of Arg, Lys, His, Orn or Cys and y is any number selected from 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21-30, 31-40, 41-50, 51-60, 61-70, 71-80 and 81-90, provided that the overall content of Arg (Arginine), Lys (Lysine), His (Histidine) and Orn (Ornithine) represents at least 10% of all amino acids of the oligopeptide. Further, the cationic or polycationic peptide may be selected from subformula (lb):

Cysl {(Arg)l;(Lys)m;(His)n;(Orn)o;(Xaa)x> Cys2 subformula (lb) wherein empirical formula {(Arg)l;(Lys)m;(His)n;(Orn)o;(Xaa)x} (formula (I)) is as defined herein and wherein Cysl and Cys2 are Cysteines proximal to, or terminal to (Arg)l;(Lys)m;(His)n;(Orn)o;(Xaa)x. In the context of polymeric carrier compounds, the disclosure of WO2012/013326 is incorporated herein by reference.

In preferred embodiments, the cationic or polycationic peptide comprises or consists of the peptide CR12C (SEQ ID NO: 10) or CR12 (SEQ ID NO: 11) or WR12C (SEQ ID NO: 12), preferably to form a polymeric carrier molecule (as described in the following).

In other embodiments, the at least one cationic or polycationic compound in the second component may be a polymeric carrier molecule according to generic formula (II):

L-Pl-S-[S-P2-S]n-S-P3-L

wherein

PI and P3 are different or identical to each other and represent a linear or branched hydrophilic polymer chain, each PI and P3 exhibiting at least one -SH-moiety, capable to form a disulfide linkage upon condensation with component P2, or alternatively with (AA)x, or [(AA)x]z if such components are used as a linker between PI and P2 or P3 and P2) and/or with further components (e.g. (AA)x, [(AA)x]z or L), the linear or branched hydrophilic polymer chain selected independent from each other from polyethylene glycol (PEG), poly-N-(2- hydroxypropyl)methacrylamide, poly-2-(methacryloyloxy)ethyl phosphorylcholines, poly(hydroxyalkyl L-asparagine), poly(2-(methacryloyloxy)ethyl phosphorylcholine), hydroxyethylstarch or poly(hydroxyalkyl L-glutamine), wherein the hydrophilic polymer chain exhibits a molecular weight of about 1 kDa to about 100 kDa, preferably of about 2 kDa to about 25 kDa; or more preferably of about 2 kDa to about 10 kDa, e.g. about 5 kDa to about 25 kDa or 5 kDa to about 10 kDa; is a cationic or polycationic peptide or protein, and preferably having a length of about 3 to about 100 amino acids, more preferably having a length of about 3 to about 50 amino acids, even more preferably having a length of about 3 to about 25 amino acids, e.g. a length of about 3 to 10, 5 to 15, 10 to 20 or 15 to 25 amino acids, more preferably a length of about 5 to about 20 and even more preferably a length of about 10 to about 20;

is a cationic or polycationic polymer, typically having a molecular weight of about 0.5 kDa to about 30 kDa, including a molecular weight of about 1 kDa to about 20 kDa, even more preferably of about 1.5 kDa to about 10 kDa, or having a molecular weight of about 0.5 kDa to about 100 kDa, including a molecular weight of about 10 kDa to about 50 kDa, even more preferably of about 10 kDa to about 30 kDa;

each P2 exhibiting at least two -SH-moieties, capable to form a disulfide linkage upon condensation with further components P2 or component(s) PI and/or P3 or alternatively with further components (e.g. (AA)x, or [(AA)x]z)

is a (reversible) disulfide bond (the brackets are omitted for better readability), wherein S preferably represents sulphur or a -SH carrying moiety, which has formed a (reversible) disulfide bond. The (reversible) disulfide bond is preferably formed by condensation of -SH- moieties of either components PI and P2, P2 and P2, or P2 and P3, or optionally of further components as defined herein (e.g. L, (AA)x, [(AA)x]z, etc.); The -SH-moiety may be part of the structure of these components or added by a modification as defined below;

is an optional ligand, which may be present or not, and may be selected independent from the other from RGD, Transferrin, Folate, a signal peptide or signal sequence, a localization signal or sequence, a nuclear localization signal or sequence (NLS), an antibody, a cell penetrating peptide, (e.g. TAT or KALA), a ligand of a receptor (e.g. cytokines, hormones, growth factors etc.), small molecules (e.g. carbohydrates like mannose or galctose or synthetic ligands), small molecule agonists, inhibitors or antagonists of receptors (e.g. RGD peptidomimetic analogues) etc.;

is an integer, typically selected from a range of about 1 to 50, preferably from a range of about

1, 2 or 3 to 30, more preferably from a range of about 1, 2, 3, 4, or 5 to 25, or a range of about 1, 2, 3, 4, or 5 to 20, or a range of about 1, 2, 3, 4, or 5 to 15, or a range of about 1,

2, 3, 4, or 5 to 10, including e.g. a range of about 4 to 9, 4 to 10, 3 to 20, 4 to 20, 5 to 20, or

10 to 20, or a range of about 3 to 15, 4 to 15, 5 to 15, or 10 to 15, or a range of about 6 to

11 or 7 to 10. Most preferably, n is in a range of about 1, 2, 3, 4, or 5 to 10, more preferably in a range of about 1, 2, 3, or 4 to 9, in a range of about 1, 2, 3, or 4 to 8, or in a range of about 1, 2, or 3 to 7. of polymeric carrier molecules, the disclosure of WO2011/026641 is incorporated herein by

In a specific embodiment, the complexed RNA molecules are complexed with a polymeric carrier molecule comprising HO-PEG5000-S-(S-CHHHHHHRRRRHHHHHHC-S-)7-S-PEG5000-OH (CHHHHHHRRRRHHHHHHC is exemplarily depicted in SEQ ID NO: 13), wherein PEG5000 denotes a polyethylene glycol (PEG) moiety having a molecular weight of approx. 5,000 Da. In specific embodiments, the polymeric carrier consists of a (R12C)-(R12C) dimer, a (WR12C)-(WR12C) dimer, or a (CR12)-(CR12C)-(CR12) trimer, wherein the individual cationic peptide (elements) in the dimer (e.g., (WR12C)), or the trimer (e.g., (CR12)) are connected via -SH groups of their cysteine residues. Further preferred cationic or polycationic compounds, which may be comprised in the second component may include cationic polysaccharides, for example chitosan, polybrene, cationic polymers, e.g. polyethyleneimine (PEI), cationic lipids, lipidoids, ionizable lipids, e.g. DOTMA: [l-(2,3-sioleyloxy)propyl)]-N,N,N- trimethylammonium chloride, DMRIE, di-C14-amidine, DOTIM, SAINT, DC-Chol, BGTC, CTAP, DOPC, DODAP, DOPE: Dioleyl phosphatidylethanol-amine, DOSPA, DODAB, DOIC, DMEPC, DOGS: Dioctadecylamidoglicylspermin, DIMRI: Dimyristo-oxypropyl dimethyl hydroxyethyl ammonium bromide, DOTAP: dioleoyloxy-3-(trimethylammonio)-propane, DC-6-14: 0,0-ditetradecanoyl-N-(a- trimethylammonioacetyl)diethanolamine chloride, CLIPl : rac-[(2,3-dioctadecyloxypropyl)(2-hydroxyethyl)]- dimethylammonium chloride, CLIP6: rac-[2(2,3-dihexadecyloxypropyl-oxymethyloxy)ethyl]-trimethylammonium, CLIP9: rac-[2(2,3-dihexadecyloxypropyl-oxysuccinyloxy)ethyl]-trimethylammonium, oligofectamine, or cationic or polycationic polymers, e.g. modified polyaminoacids, such as β-aminoacid-polymers or reversed polyamides, etc., modified polyethylenes, such as PVP (poly(N-ethyl-4-vinylpyridinium bromide)), etc., modified acrylates, such as pDMAEMA (poly(dimethylaminoethyl methylacrylate)), etc., modified Amidoamines such as pAMAM (poly(amidoamine)), etc., modified polybetaaminoester (PBAE), such as diamine end modified 1,4 butanediol diacrylate-co-5-amino-l-pentanol polymers, etc., dendrimers, such as polypropylamine dendrimers or pAMAM based dendrimers, etc., polyimine(s), such as PEI: poly(ethyleneimine), poly(propyleneimine), etc., polyallylamine, sugar backbone based polymers, such as cyclodextrin based polymers, dextran based polymers, chitosan, etc., silan backbone based polymers, such as PMOXA-PDMS copolymers, etc., blockpolymers consisting of a combination of one or more cationic blocks (e.g. selected from a cationic polymer as mentioned above) and of one or more hydrophilic or hydrophobic blocks (e.g polyethyleneglycole); etc.

In a further preferred embodiment, the nucleic acid, particularly the RNA may also be complexed - alternatively or in addition to a cationic or polycationic compound - by a compound selected from the group of polymers or complexing agents, typically comprising, without being limited thereto, any polymer suitable for the preparation of a pharmaceutical composition, such as minor/major groove binders, nucleic acid binding proteins, lipids, lipoplexes, nanoplexes, non-cationic or non-polycationic compounds, such as PLGA, Polyacetate, Polyacrylate, PVA, Dextran, hydroxymethylcellulose, starch, MMP, PVP, heparin, pectin, hyaluronic acid, and derivatives thereof.

In a further preferred embodiment, the nucleic acid, particularly the RNA may also be complexed with at least one lipid comprised in the second component to form a liposome, lipid nanoparticle (LNP) or lipoplex.

In the context of the present invention, the term "lipid nanoparticle", also referred to as LNP, is not restricted to any particular morphology, and include any morphology generated when a cationic lipid and optionally one or more further lipids are combined according to the invention, e.g. in an aqueous environment and/or in the presence of a nucleic acid, particularly the RNA. For example, a liposome, a lipid complex, a lipoplex and the like are within the scope of a lipid nanoparticle (LNP). An LNP in that context may comprise any lipid capable of forming a particle to which the nucleic acid, particularly the RNA, is attached, or in which the nucleic acid, particularly the RNA, is encapsulated. Preferably, the LNP comprising one or more RNA molecules comprises one or more cationic lipids, and one or more stabilizing lipids. Stabilizing lipids include neutral lipids and PEGylated lipids.

In one embodiment, the LNP as defined herein may essentially consist of (i) at least one cationic lipid; (ii) a neutral lipid; (iii) a sterol, e.g. cholesterol; and (iv) a PEG-lipid, e.g. PEG-DMG or PEG-cDMA, in a molar ratio of about 20-60% cationic lipid: 5-25% neutral lipid: 25-55% sterol; 0.5-15% PEG-lipid. A preferred sterol comprised in the second component suitable to form LNPs as defined herein is cholesterol. The sterol can be about 10 mol % to about 60 mol % or about 25 mol % to about 40 mol % of the lipid particle. In one embodiment, the sterol is about 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or about 60 mol % of the total lipid present in the lipid particle. In another embodiment, the LNPs include from about 5% to about 50% on a molar basis of the sterol, e.g., about 15% to about 45%, about 20% to about 40%, about 48%, about 40%, about 38.5%, about 35%, about 34.4%, about 31.5% or about 31% on a molar basis (based upon 100% total moles of lipid in the lipid nanoparticle).

The cationic lipid comprised in the second component suitable to form LNPs as defined herein may be cationisable, i.e. it becomes protonated as the pH is lowered below the pK of the ionizable group of the lipid, but is progressively more neutral at higher pH values. At pH values below the pK, the cationic lipid is then able to associate with negatively charged nucleic acids. In certain embodiments, the cationic lipid comprises a zwitterionic lipid that assumes a positive charge on pH decrease.

The LNP may comprise any further cationic or cationisable lipid, i.e. any of a number of lipid species which carry a net positive charge at a selective pH, such as physiological pH.

Such cationic or cationisable lipids comprised in the second component suitable to form LNPs as defined herein may include N,N-dioleyl-N,N-dimethylammonium chloride (DODAC); N-(2,3-dioleyloxy)propyl)-N,N,N- trimethylammonium chloride (DOTMA); N,N-distearyl-N,N-dimethylammonium bromide (DDAB); N- (2,3dioleoyloxy)propyl)-N,N,N-trimethylammonium chloride (DOTAP); 3-(N-(N',N'dimethylaminoethane)- carbamoyl)cholesterol (DC-Choi), N-(l-(2,3-dioleoyloxy)propyl)N-2-(sperminecarboxamido)ethyl)-N,N- dimethylammonium trifluoroacetate (DOSPA), dioctadecylamidoglycyl carboxyspermine (DOGS), l,2-dioleoyl-3- dimethylammonium propane (DODAP), N,N-dimethyl-2,3-dioleoyloxy)propylamine (DODMA), and N- (l,2dimyristyloxyprop-3-yl)-N,N-dimethyl-N-hydroxyethyl ammonium bromide (DMRIE).

Additionally, a number of commercial preparations of cationic lipids are available which can be used in the present invention. These may be comprised in the second component, including for example, LIPOFECTIN® (commercially available cationic liposomes comprising DOTMA and l,2-dioleoyl-sn-3phosphoethanolamine (DOPE), from GIBCO/BRL, Grand Island, N.Y.); LIPOFECTAMINE® (commercially available cationic liposomes comprising N-(l-(2,3dioleyloxy)propyl)-N-(2-(sperminecarboxamido)ethyl)-N,N-dimethylammonium trifluoroacetate (DOSPA) and (DOPE), from GIBCO/BRL); and TRANSFECTAM® (commercially available cationic lipids comprising dioctadecylamidoglycyl carboxyspermine (DOGS) in ethanol from Promega Corp., Madison, WI, USA). The following lipids are cationic and have a positive charge at below physiological pH: DODAP, DODMA, DMDMA, l,2-dilinoleyloxy-N,N-dimethylaminopropane (DLinDMA), l,2-dilinolenyloxy-N,N- dimethylaminopropane (DLenDMA).

The further cationic lipid comprised in the second component suitable to form LNPs as defined herein may also be an amino lipid. Representative amino lipids include, but are not limited to, l,2-dilinoleyoxy-3- (dimethylamino)acetoxypropane (DLin-DAC), l,2-dilinoleyoxy-3morpholinopropane (DLin-MA), l,2-dilinoleoyl-3- dimethylaminopropane (DLinDAP), l,2-dilinoleylthio-3-dimethylaminopropane (DLin-S-DMA), l-linoleoyl-2- linoleyloxy-3dimethylaminopropane (DLin-2-DMAP), l,2-dilinoleyloxy-3-trimethylaminopropane chloride salt (DLin-TMA.CI), l,2-dilinoleoyl-3-trimethylaminopropane chloride salt (DLin-TAP.CI), l,2-dilinoleyloxy-3-(N- methylpiperazino)propane (DLin-MPZ), 3-(N,Ndilinoleylamino)-l,2-propanediol (DLinAP), 3-(N,N-dioleylamino)- 1,2-propanediol (DOAP), l,2-dilinoleyloxo-3-(2-N,N-dimethylamino)ethoxypropane (DLin-EG-DMA), and 2,2- dilinoleyl-4-dimethylaminomethyl-[l,3]-dioxolane (DLin-K-DMA), 2,2- dilinoleyl-4-(2-dimethylaminoethyl)-[l,3]- dioxolane (DLin-KC2-DMA); dilinoleyl-methyl-4- dimethylaminobutyrate (DLin-MC3-DMA); MC3 (the information hereon is incorporated by reference from US 2010/0324120).

The amount of the permanently cationic lipid or lipidoid may be selected taking the amount of the nucleic acid, particularly of RNA into account. In one embodiment, these amounts are selected such as to result in an N/P ratio of the nanoparticle(s) or of the composition in the range from about 0.1 to about 20. In this context, the N/P ratio is defined as the mole ratio of the nitrogen atoms ("N") of the basic nitrogen-containing groups of the lipid or lipidoid to the phosphate groups ("P") of the RNA which is used as cargo. The N/P ratio may be calculated on the basis that, for example, 1 pg RNA typically contains about 3 nmol phosphate residues, provided that the RNA exhibits a statistical distribution of bases. The "N"-value of the lipid or lipidoid may be calculated on the basis of its molecular weight and the relative content of permanently cationic and - if present - cationisable groups.

In certain embodiments, the LNP comprises one or more additional lipids which stabilize the formation of particles during their formation.

Stabilizing lipids comprised in the second component suitable to form LNPs as defined herein include neutral lipids and anionic lipids. The term "neutral lipid" refers to any one of a number of lipid species that exist in either an uncharged or neutral zwitterionic form at physiological pH. Representative neutral lipids include diacylphosphatidylcholines, diacylphosphatidylethanolamines, ceramides, sphingomyelins, dihydro sphingomyelins, cephalins, and cerebrosides. Exemplary neutral lipids include, for example, distearoylphosphatidylcholine (DSPC), dioleoylphosphatidylcholine (DOPC), dipalmitoylphosphatidylcholine (DPPC), dioleoylphosphatidylglycerol (DOPG), dipalmitoylphosphatidylglycerol (DPPG), dioleoyl- phosphatidylethanolamine (DOPE), palmitoyloleoylphosphatidylcholine (POPC), palmitoyloleoyl- phosphatidylethanolamine (POPE) and dioleoyl-phosphatidylethanolamine 4-(N-maleimidomethyl)-cyclohexane- lcarboxylate (DOPE-mal), dipalmitoyl phosphatidyl ethanolamine (DPPE), dimyristoylphosphoethanolamine (DMPE), distearoyl-phosphatidylethanolamine (DSPE), 16-O-monomethyl PE, 16-O-dimethyl PE, 18-1-trans PE, l-stearioyl-2-oleoylphosphatidyethanol amine (SOPE), and l,2-dielaidoyl-sn-glycero-3-phophoethanolamine (transDOPE). In one embodiment, the neutral lipid is l,2-distearoyl-sn-glycero-3phosphocholine (DSPC). In some embodiments, the LNPs comprise a neutral lipid selected from DSPC, DPPC, DMPC, DOPC, POPC, DOPE and SM. In various embodiments, the molar ratio of the cationic lipid to the neutral lipid ranges from about 2:1 to about 8:1. In some embodiments, the LNPs comprise a polymer conjugated lipid. The term "polymer conjugated lipid" refers to a molecule comprising both a lipid portion and a polymer portion. An example of a polymer conjugated lipid is a PEGylated lipid. The term "PEGylated lipid" refers to a molecule comprising both a lipid portion and a polyethylene glycol portion. PEGylated lipids are known in the art and include l-(monomethoxy-polyethylene glycol)-2,3-dimyristoylglycerol (PEG-s- DMG) and the like.

In certain embodiments, the LNP comprises an additional, stabilizing-lipid which is a polyethylene glycol-lipid (PEGylated lipid). Stabilizing lipids comprised in the second component suitable to form LNPs as defined herein include polyethylene glycol-lipids include PEG-modified phosphatidylethanolamine, PEG-modified phosphatidic acid, PEG-modified ceramides (e.g., PEG-CerCi4 or PEG-CerC2o), PEG-modified dialkylamines, PEG-modified diacylglycerols, PEG-modified dialkylglycerols. Representative polyethylene glycol-lipids include PEG-c-DOMG, PEG-c-DMA, and PEG-s-DMG. In one embodiment, the polyethylene glycol-lipid is N-[(methoxy poly(ethylene glycol)2ooo)carbamyl]-l,2-dimyristyloxlpropyl-3-amine (PEG-c-DMA). In one embodiment, the polyethylene glycol-lipid is PEG-c-DOMG). In other embodiments, the LNPs comprise a PEGylated diacylglycerol (PEG-DAG) such as l-(monomethoxy-polyethyleneglycol)-2,3-dimyristoylglycerol (PEG-DMG), a pegylated phosphatidyl- ethanoloamine (PEG-PE), a PEG succinate diacylglycerol (PEG-S-DAG) such as 4-0-(2',3'-di(tetradeca- noyloxy)propyl-l-0-(co-methoxy(polyethoxy)ethyl)butanedioate (PEG-S-DMG), a PEGylated ceramide (PEG-cer), or a PEG dialkoxypropylcarbamate such as ω-methoxy(polyethoxy)ethyl-N-(2,3di(tetradecanoxy)propyl)- carbamate or 2,3-di(tetradecanoxy)propyl-N-(ω-methoxy(polyethoxy)ethyl)-carbamate. In various embodiments, the molar ratio of the cationic lipid to the PEGylated lipid ranges from about 100:1 to about 25:1.

Preferably, the second component comprises water as a solvent. Additionally, the second component may comprise one or more of solvent miscible with water. Examples of such water-miscible solvents are known in the art. Preferred examples of additional solvents are alcohols, such as, e.g. ethanol, etc., DMSO, and the like. Especially preferred, the additional solvent is pharmaceutically acceptable. Examples of pharmaceutically acceptable solvents are, e.g. ethanol, etc.

Preferably, the second component is an aqueous solution of the at least one cationic or polycationic compound, which optionally comprises at least one further component, wherein the at least one further compound is selected from a salt and/or preferably a lyoprotectant as defined herein.

In an embodiment, the second component has a viscosity of from 100-5000mm²/s, preferably from 500- 2500mm²/s, more preferably from 1000-1500mm²/s. In a preferred embodiment, the second component, preferably comprising a polycationic compound (preferably protamine) and/or a lyoprotectant (preferably trehalose), has a viscosity of approximately 1.206mm²/s.

Preferably, the first liquid composition and/or the second liquid composition comprise at least one component selected from the group of carbohydrates. Such group of carbohydrates may comprise, without being limited thereto, any carbohydrate, suitable for the preparation of a pharmaceutical composition, preferably, without being limited thereto, monosaccharides, such as e.g. glucose, fructose, galactose, sorbose, mannose etc., and mixtures thereof; disaccharides, such as e.g. lactose, maltose, sucrose, trehalose, cellobiose, etc., and mixtures thereof; polysaccharides, such as raffinose, melezitose, maltodextrins, dextrans, starches, etc., and mixtures thereof; and alditols, such as mannitol, xylitol, maltitol, lactitol, xylitol sorbitol, pyranosyl sorbitol, myoinositol, etc., and mixtures thereof. Examples of sugars that are preferably used in the composition according to the invention include lactose, sucrose or trehalose. Generally, a sugar that is preferred in this context has a high water displacement activity and a high glass transition temperature. Furthermore, a sugar suitable for use in the first and/or second liquid composition is preferably hydrophilic but not hygroscopic. In addition, the sugar preferably has a low tendency to crystallize, such as trehalose.

Preferably, the first liquid component and/or second liquid component comprise at least one further compound selected from a cryoprotectant, a lyoprotectant or a bulking agent. In this context, cryoprotectants are understood as excipients, which allow influencing the structure of a frozen material and/or the eutectic temperature of the mixture. Lyoprotectants are typically excipients, which partially or totally replace the hydration sphere around a molecule and thus prevent catalytic and hydrolytic processes. A bulking agent (e.g. a filler) is any excipient compatible with the nucleic acid (RNA, DNA) and/or the cationic or polycationic compound. As used herein, a bulking agent may be used for increasing the volume and/or the mass of the liquid compositions. In addition, a bulking agent may also protect the nucleic acid, particularly the RNA from degradation.

In a preferred embodiment, the second liquid component comprises at least one lyoprotectant. According to one embodiment, the lyoprotectant is selected from the group consisting of glucose, fructose, sucrose, mannose, trehalose, mannitol, polyvinylpyrrolidone, and Ficoll 70 or mixtures thereof. In a preferred embodiment the lyoprotectant is trehalose.

In an embodiment, the concentration of a lyoprotectant, preferably as defined herein, in the second liquid component is in a range of about 0.01 to about 40% (w/w), preferably of about 0.01 to about 30% (w/w), more preferably of about 0.1 to about 20% (w/w), even more preferably of about 1 to about 20% (w/w), and most preferably of about 5 to about 15% (w/w), e.g. of about 8 to about 14% (w/w), such as about 10 % (w/w).

Preferably, the second component comprises a cationic or polycationic compound in a concentration of from 0.05 to 10.00 g/L, preferably of from 0.10 to 5.00 g/L, more preferably of from 0.10 to 1.0 g/L and most preferably of from 0.1 to 0.5 g/L. Mixing:

In the context of the invention, "mixing" is typically a process that involves manipulation of a heterogeneous physical system with the intent to make it more homogeneous. Mixing is performed to allow mass transfer to occur between one or more streams, components or phases. Mixing is fundamentally the evolution in time of spatially dependent concentrations toward a final homogeneous state.

In the context of the present invention, a swirling element is used, which allows for an improved mixing of the components as defined herein, preferably without exerting any mechanical stress (such as shear stress) on said components. It is believed that the stability of the nucleic acid, preferably the RNA, preferably a long chain RNA or an mRNA as defined herein, the cationic or polycationic compound and/or of the nanoparticle is increased by using the swirling element of the invention. In particular, conventional mixing means that are known to induce mechanical stress on the components to be mixed are preferably avoided according to the present invention. For example, the first component and the second component are preferably mixed without shaking and/or agitating the components.

The term "swirling" refers to introducing turbulences in the first and/or second component (via bends, baffles etc.) that are not caused by shaking or vibrating which allows for an improved mixing of the two components to generate a homogeneous nucleic acid nanoparticle comprising composition.

Blend time:

The term "blend time" (also referred to as "mixing time" or "macro-mixing time" in the art) is used to indicate the time required to reach a predefined degree of homogeneity in a vessel or reactor (also referred to as 'uniformity') under predetermined reaction conditions. The blend time is known to depend on the design of the respective mixing device as well as various operational conditions of the mixing device, for example, on size and geometry of the reaction chamber (mixing chamber, in the context of the invention a static mixing element), the mixing rate, size and geometry of optional baffles, energy input, the flow rate of the individual solutions (first and second component), viscosity of the solutions, temperature, and the like, which are readily adjusted accordingly by the skilled person.

In the context of the present invention, "blend time" typically refers to the time required reaching homogeneity (uniformity) of the mixture of at least 50%. Preferably, the homogeneity (uniformity) is 50% or more, more preferably 60% or more, more preferably 70% or more, more preferably 80% or more and most preferable 90% or more.

According to the invention, the blend time amounts to 5 seconds or less. Preferably, the blend time is 2.5 seconds or less, more preferably 2.0 seconds or less, more preferably, 1.0 second or less, more preferably 0.5 second or less, more preferably 0.25 second or less, more preferably 0.1 seconds or less and most preferably 0.05 seconds or less. Alternatively, the blend time is preferably in a range from about 0.001 seconds to about 5 seconds, more preferably from about 0.01 seconds to about 5 seconds, even more preferably from about 0.1 seconds to about 5 seconds and most preferably from about 0.001 to about 2 seconds or from about 0.01 to about 2 seconds.

Preferably, the blend time is experimentally determined, preferably by a method selected from a colorimetric method, a method based on conductivity measurements, and a chemical method. Alternatively, the blend time may be determined experimentally, preferably by a method selected from a colorimetric method, a method based on conductivity measurements, a chemical method, or by simulation, e.g. by computational fluid dynamics (CFD).

If hereinafter a group is defined to comprise at least a certain number of embodiments, this is also meant to encompass a group which preferably consists of these embodiments only.

As used in the specification and the claims, the singular forms of "a" and "an" also include the corresponding plurals unless the context clearly dictates otherwise. It needs to be understood that the term "comprising" is not limiting. For the purposes of the present invention, the term "consisting of" is considered to be a preferred embodiment of the term "comprising of". Detailed Description of the findings underlying the present invention

The inventors conducted intensive studies to develop devices and methods for a flexibly scalable, economical, controllable, reproducible, continuous, GMP- and HT-compatible (that is, production of different formulations in parallel) nucleic acid (e.g., RNA, DNA) nanoparticle production.

In a first set of experiments, the inventors generated a mixing device comprising two inlet tubes (first tube: first component comprising an RNA solution; second tube: second component comprising protamine and trehalose solution) and an outlet tube, connected via a T-piece connector, wherein the fluid flow was driven by a peristaltic pump. The inventors surprisingly found that such a simple setup (herein referred to as "T-piece connector static mixing device" allowed for a scalable, reproducible and reliable nucleic acid nanoparticle production (see Figure 1 and Example 3).

To further analyse the mixing behaviour of the fluids (that is, first - and second component), also for larger flow rates, the inventors conducted computational fluid dynamics (CFD) analysis. To calculate the fluid dynamics, the inventors used a computational model of the T-piece connector static mixing device. The inventors show that also for larger flow rates (760ml/min) sufficient mixing of the two fluids occurred, suggesting that said setup is particularly suitable for large-scale nucleic acid nanoparticle production (see Figures 2 and 3 as well as Example 4). However, such a setup would not meet the requirements for GMP-compatible or HT-compatible nanoparticle production.

To further simplify the above developed T-piece connector static mixing device, and to narrow down the element responsible for the mixing of the two fluids, and to determine the influence of different formulation parameters (e.g. flow rate) and geometry of the mixing device, the inventors conducted computational fluid dynamics (CFD) analysis using T-piece and Y-piece elements as models. The inventors found that the use of T-piece or Y-piece elements alone (without tubing elements) did not sufficiently mix the fluids (see Figure 4 and Example 5).

Based on the results obtained in Example 4 and Example 5, the inventors generated several designs of mixing devices comprising swirling elements, where bends were introduced in the inlet port and/or the outlet port (see Figure 5). Figure 5 shows mixing devices according to the invention for the production of a liquid nucleic acid composition. In particular, Figures 5A-D show four different exemplary designs used in the CFD analysis. The different designs are shown in three different views, which are an overview, a front view and a top view. Further details of the CFD analysis are provided in Example 6.

As shown in Figures 5A-D, the mixing device for the production of a liquid nucleic acid composition according to the invention comprises: a first inlet tube 8a for a first component 2 comprising a nucleic acid solution,

a second inlet tube 8b for a second component 3, a connecting element 1, and

an outlet tube 9.

The connecting element 1 connects the first inlet tube 8a and the second inlet tube 8b to the outlet tube 9. The connecting element is static and has a T-shape.

The first inlet tube 8a, the second inlet tube 8b and the outlet tube 9 (only in Figures 5C and 5D) each comprises a swirling element 13 in form of a bend to introduce a swirling of the first component 2 and the second component 3 in the respective inlet tubes 8a, 8b and (only in Figures 5C and 5D) the outlet tube 9 to allow a mixing of the first component 2 and the second component 3 to produce the liquid nucleic acid composition.

The swirling element 13 has here a form of a bend comprising two antidromic curved curves to form an S-shape or Z-shape. The bend or its curves bend about 90° relative to the respective tube 8a, 8b and 9. In Figures 5A and 5B, the bends lie in the plane of the respective tube 8a, 8b. In Figures 5C and 5D, the bend protrudes essentially perpendicular out of the plane of the respective tube 8a, 8b and 9. The swirling element may alternatively or additionally to the bend comprise at least one baffle (not shown), preferably at least one baffle at the outlet port and/or the inlet port. The inventors surprisingly found that the introduction of at least one bend in the inlet tube led to a sufficient mixing of the two fluids. The improved mixing was potentially caused by the at least one bend in the inlet port, which created a swirling of the fluids, generating a rotation of the fluids in both inlet ports, which eventually caused the mixing of the fluids in the mixing or swirling elements. The mixing of the fluids was further improved by introducing at least one bend in the outlet port (see Figures 6-9).

To design a large-scale, GMP-compatible mixing device, the inventors designed a hose routing 11 (see Figure 10) e.g. constructed via 3D printing, wherein the hose routing 11 comprises the mixing device shown in Figure 5C integrated into a table element 10. Such a design allows for a nucleic acid nanoparticle formulation in a regulated environment, because single use materials such as single use tubes can be placed into the hose routing to generate nucleic acid nanoparticle formulations (see Figure 11). The experimental testing of the design according to Figure 11 showed that the GMP-compatible mixing device is suitable for the robust, scalable industrial formulation of high-quality homogeneous solutions of nucleic acid comprising nanoparticles (see Figures 14 - 16). Further, the GMP-compatible mixing device of the invention is suitable for a robust, scalable, industrial formulation of immune stimulatory RNA nanoparticles ("RN Adjuvant"; see Example 11).

In preferred embodiments, the tube that is placed into the hose routing 11 is made of GMP-compatible materials. In preferred embodiments, the tube is a silicone or a PET tube, most preferably as single-used materials. In other embodiments, the tube is manufactured using other materials, e.g. stainless steel. In embodiments, the tubes according to the present invention are solid tubes, matching the design of e.g. manufactured from plastic materials. Preferably, the used materials are GMP-compatible materials. Furthermore, the inventors use a plurality of mixing devices 20, e.g. with a design as shown in Figure 5C, to form a mixing array 30 for HT-compatible and GMP-compatible formulation of nucleic acid nanoparticle comprising solutions (see Figure 13). Such miniaturized mixing devices may be manufactured using 3D printing, potentially comprising screw elements 14, or alternatively, manufactured as such the mixing device is directly attached to a capture vial 7 (see Figure 12). Figure 12A shows an example of a mixing device comprising a screw element 14 to allow attachment of the mixing device on a capture module, e.g. a vial 7. Figure 12B shows a mixing device, which is directly attached to a capture vial 7.

The miniaturized mixing devices may also allow for high throughput applications, e.g. for the parallel formulation of (different) nucleic acid comprising compositions. In one embodiment, 6, 12, 24, 48, 96 mixing devices 20 are used as a multi-array element 30 to manufacture various different nucleic acid nanoparticle comprising solutions (see Figure 13) without the danger of cross-contaminations. Figure 13 shows an example of a multi-array element 30 of several mixing devices 20 suitable for high throughput (HT) applications. The two solutions (nucleic acid comprising solution 2 and protamine/trehalose solution 3) are formulated to form different nucleic acid nanoparticle comprising compositions (compositions A - F) in parallel. Such a miniaturized mixing device as illustrated in Figure 13 may also be used for HT formulation of LNP nanoparticles comprising nucleic acids (see Example 8).

It has to be noted that embodiments of the invention are described with reference to different subject matters. In particular, some embodiments are described with reference to method type claims whereas other embodiments are described with reference to the device type claims. However, a person skilled in the art will gather from the above and the following description that, unless otherwise notified, in addition to any combination of features belonging to one type of subject matter also any combination between features relating to different subject matters is considered to be disclosed with this application. However, all features can be combined providing synergetic effects that are more than the simple summation of the features.

While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing a claimed invention, from a study of the drawings, the disclosure, and the dependent claims.

In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are re-cited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Examples The following Examples are merely illustrative and shall describe the present invention in a further way. The Examples shall not be construed to limit the present invention thereto. Example 1: Preparation of RNA and protamine solutions

1. Preparation of DNA and mRNA constructs:

For the present Examples, a DNA sequence encoding the hemagglutinin (HA) protein of influenza A virus (A/Netherlands/602/2009(HlNl)) was prepared by modifying the wild type coding HA DNA sequence by GC- optimization for stabilization. The GC-optimized HA DNA sequence was introduced into a pUC19 derived vector and modified to comprise a 5'-TOP-UTR derived from the ribosomal protein 32L4, and a stabilizing 3'UTR sequence derived from the albumin-3'-UTR, a stretch of 64 adenosines (poly(A)-sequence), a stretch of 30 cytosines (poly(C)-sequence), and a histone stem loop. The obtained plasmid DNA was used for RNA in vitro transcription experiments to obtain HA RNA (SEQ ID NO: 6).

2. RNA in vitro transcription:

The obtained DNA plasmid was linearized using EcoRI and transcribed in rafro using T7 RNA polymerase (Thermo Fisher Scientific Inc.) in the presence of a suitable buffer and a nucleotide mixture and a cap analog (m7GpppG). Subsequently, the obtained RNA was purified using PureMessenger® (CureVac, Tubingen, Germany; WO2008/077592A1).

3. Preparation of standard RNA solution:

A standard RNA solution was prepared in purified water wherein the concentration of RNA was 0.87g/L, further comprising about 9mM Na and about 6.5mM CI. The ratio Na/RNA was about 10.3mmol/g. The pH of the solution was 5.8. In other experiments, a standard RNA solution was prepared in purified water wherein the concentration of RNA was 0.87g/L, and wherein the RNA solution did not comprise additional Na or CI. The pH of the solution was in a range of pH5.8-pH7.0.

4. Preparation of the protamine solution

For the model reaction used in all Examples and Reference Examples described in the following, a standard solution containing protamine (Meda Pharma) and trehalose (Ferro Pfanstiehl) was prepared in purified water. The concentration of protamine was 0.43g/L (corresponding to 43.9Units/mL), and the concentration of trehalose was 10.87% (w/w). For respective model reactions using that protamine solution comprising protamine obtained from Meda Pharma, the RNA solution did comprise additional NaCI (see section above).

For other Examples, GMP-grade protamine (LeoPharma GmbH; comprising 147mM NaCI) was used. The concentration of GMP-grade protamine was 0.314g/L (correspornding to 43.9Units/mL of protamine), and the concentration of trehalose was 10.87% (w/w). For respective model reactions using the protamine solution comprising GMP-grade protamine, the RNA solution did not comprise additional NaCI (see section above)

Example 2: Characterization of product dispersions:

1. Characterization of nanoparticles: Measurement of particle size and polvdispersitv:

Measurement of the average particle size using Zetasizer: The hydrodynamic diameter of the nanoparticles was measured by dynamic light scattering using a Zetasizer Nano ZS (Malvern Instruments, Malvern, UK) according to the instructions provided by the manufacturer. The measurements were performed at 25°C and a scattering angle of 173° in the specified buffer analyzed by a cumulative method to obtain the hydrodynamic diameters and polydispersity indices of the nanoparticles.

For measuring the particle size of the RNA-protamine nanoparticles obtained in dispersion according to the method of the present invention in the Examples and Reference Examples, 70ul of the respective product solution was filled into a UV transmittable cuvette (UVette, Eppendorf), which in turn was placed into a Zetasizer nano ZS (Malvern instruments) and the measurement was conducted using the following settings: Refractive index of material: 1.450; absorption of material: 0.001; dispersant temperature: 25°C; dispersant viscosity: 0.8753; dispersant refractive index: 1.331; Mark-Houwink parameters: A parameter 0.428; K-parameter 7.67-05cm²/s; use dispersant viscosity as sample viscosity; sample temperature: 25°C; sample cuvette: Zen 0040 disposable cuvette, equilibration time: 0s; measurement angle: 173° backscatter; automatic measurement duration; number of measurements: 1; automatic attenuation setting; positioning method: seek for optimal position; no extension duration for large particles; analysis model: normal resolution. An average particle size (hydrodynamic diameter of a particle in nm) is given as a Z-average and a polydispersity is given as a polydispersity index (PDI), both of which were calculated by the instrument's software (Zetasizer software version 6.34, Malvern Instruments). Polydispersity describes the width of a population distribution. It describes the degree of heterogeneity of a population. In this context, polydispersity represents the width of the particle size distribution of the nanoparticles present in a liquid composition, particularly the width of the particle size distribution of the product RNA-comprising nanoparticles. The polydispersity index (PDI) is a dimensionless measure of the broadness of the size distribution in nanoparticle samples. Polydispersity index values below 0.1 indicate a monomodal distribution, while a polydispersity index over 0.5 indicates a broad distribution of particle sizes.

It has to be noted that for the formulation of nanoparticle comprising compositions, an average particle size smaller than 200nm was desired, indicating the formation of homogeneous nanoparticles. Measurement of the absorption at 350nm (A350):

The transmitted light through a sample solution can be measured in a UV-Vis spectrophotometer at a wavelength where the ingredients, such as proteins, peptides, DNA/RNA, and formulation excipients do not absorb light, i.e., typically in the range of 320-800nm. To rapidly measure and compare the clarity of the product nanoparticle dispersion (dispersion comprising the RNA-protamine nanoparticles), the absorption at 350nm (A350) was determined. 200ul of each product dispersion were applied to a micro well plate (Costar, UV Plate, 96 well, no lid, UV transmittable flat bottom). A350 was measured with a Synergy HT plate reader (BioTek systems). Path length correction was performed by Gen5 software (BioTek, Installation version: 1.11.5) with a test wavelength of 977nm and a reference wavelength of 900 nm. Correction was performed with a constant K-factor of 0.18 to yield the A350 value corrected to 1 cm path length. Images of the plates from were taken with an E-box VX2 (Vilber) documentation system. It has to be noted that for the formulation of nanoparticle comprising compositions, an A350 value of smaller than 0.5 was desired, because larger values indicate the formation of undesired precipitates. Example 3: Static mixing device type (T-piece connector static mixing device):

1. Description of the mixing device design:

An exemplary mixing device comprising a static mixing means in form of a T-piece connector was constructed, essentially comprising of a T-piece (1/8 inch from Merck) and a peristaltic pump (Watson Marlow). The T-piece was connected to a peristaltic pump used for the introducing of 0.87 mg/ml RNA (first tube) and protamine- trehalose solution (10.86% trehalose, 0.43mg/ml protamine) (second tube). Both solutions were pumped through the T-piece (static mixing device) with various total flow rates. A schematic drawing of the T-piece connector mixing device is provided in Figure 1. A mixing device was designed comprising a T-piece connector 1 as a static mixing element. The flow of the two solutions (0.87mg/ml RNA solution 2; protamine-trehalose solution 3) was generated via a peristaltic pump(s) 4. Both solutions were pumped through the static mixer via separate inlet tubes 5 with various total flow rates. The mixing occurred in the T-piece connector 1 and the nanoparticle comprising product solution was captured via an outlet tube 6 in capture module 7 and used for downstream processing (e.g., lyophilisation).

2. Preparation of RNA-comprisino nanoparticles in the T-piece static mixing device:

The standard RNA solution (0.87g/L) and the protamine/trehalose standard solution (0.43g/L protamine; 10.87% trehalose) prepared according to Example 1 were pumped into the mixing device with the total flow rates as summarized in Table 1. In addition, quality attributes of the obtained particles were characterized, including average particle sizes (zetasizer, Z-averages), polydispersity index (PDI) and absorption at 350nm (A350), determined according to Example 2.

Table 1: Results and parameters for the static mixing device:

Results:

In all performed experiments, the inventors found that particles smaller than 200nm in average were generated in clear dispersions, without causing increased precipitation (A350 <0.5). This shows that the tested T-piece connector static mixing device works and may potentially be used for a scalable and reliable formulation of RNA nanoparticles. It has to be noted that no stirring means was necessary to obtain a homogeneous and clear nanoparticle solution. To further investigate and characterize the fluid dynamics of the mixing device, computational fluid dynamics (CFD) analysis was performed (see Example 4).

Example 4: Computational fluid dynamics (CFD) analysis of the T-piece connector static mixing device

A computational fluid dynamics (CFD) analysis was performed to determine the influence of flow-rate (e.g., influence of higher flow rates) and mixing device geometry on the blending of the RNA solution and the protamine/trehalose solution. CFD analysis was performed using a Star CCM+ software package. Figure 2 shows a computational model of a mixing device used for the CFD analysis according to Example 4. The model consisted of inlet tubes 5, a T-piece connector 1 and an outlet tube 6.

In the computational model, the physical characteristics of the RNA solution were assigned with a density of 997.9 kg/m³ and a kinematic viscosity of 2.39 mm²/s and the physical characteristics of the protamine-trehalose solution were assigned with a density of 1039.4 kg/m³ and a kinematic viscosity of 1.206 mm²/s. The CFD analysis was performed for models of the continuous mixing device with a T-piece connector described in Example 3. The model of that T-piece connector static mixing device (tubing system + T-piece connector) used in the CFD analysis is depicted in Figure 4.

The surface uniformity at 760 ml/min flow rate was determined according to the volume fraction of the protamine/trehalose solution at the outlet port. Using this method, the homogeneity of the product liquid composition was simulated over time. Figure 3 shows an exemplary result of the CFD analysis performed according to Example 4. The graph shows the homogeneity/uniformity obtained at the outlet port after a certain time period. The time point, where the homogeneity constantly reached a value of larger than 0.7 (70%) is indicated with a dashed line. Moreover, a blend time was determined. The blend time was determined as the time point where the mixture of both solutions showed a constant homogeneity/uniformity level of larger than 70%. Results:

Figure 3 shows an exemplary result of the CFD analysis performed in the current experiment. The analysis shows that sufficient mixing of the two liquid solutions (RNA solution; protamine/trehalose solution) was obtained after approximately 0.15 seconds, at a flow rate of 760ml/min. To further investigate and characterize the impact of the connector pieces on the mixing of the fluids, a further CFD analysis was conducted using T-piece connector and Y-piece connector models (see Example 4).

Example 5: Computational fluid dynamics (CFD) analysis of the T-piece connector and Y-piece connector (without tubing system) To investigate whether a simple T-piece connector or a simple Y-piece connector is sufficient for the production of a well-blended RNA nanoparticle formulation, a further CFD analysis was performed.

In the computational model, the physical characteristics of the RNA solution were assigned with a density of 997.9kg/m³ and a kinematic viscosity of 2.39mm²/s and the physical characteristics of the protamine-trehalose solution were assigned with a density of 1039.4kg/m³ and a kinematic viscosity of 1.206mm²/s. The CFD analysis was performed for models of a T-piece connector (without inlet and outlet tubes) and a Y-piece connector (without inlet and outlet tubes). The CFD analysis was computated for different flow rates (20ml, 40ml, 400ml, 760ml). The surface uniformity was determined according to the volume fraction of the protamine/trehalose solution at the outlet port for each experimental design. The results are shown in Table 2. Table 2: Results and parameters for the static mixing device:

Figure 4 shows an exemplary result of a CFD analysis performed according to Example 5. Figures 4A and

4B show the computational models for a T-piece element and Y-piece element used for the CFD analysis. Figures 4C and 4D show respective cross sections of the CFD modelling at the outlet port of a T-piece and a Y-piece respectively, illustrating that the two fluids (RNA solution marked with a white asterisk; protamine/trehalose solution marked with a white "X") do not properly mix and rather run in parallel.

Results:

The results summarized in Table 2 show that unexpectedly, the simple design chosen by the inventors (T-piece; Y-piece; both without inlet tubes) was not sufficient to mix the two solutions. The inventors found that the fluids rather run in parallel without mixing (see Figure 4 C and 4D). Interestingly, the CFD analysis performed in Example 4 showed that sufficient mixing occurred using a T-piece connector type mixing device. The only difference in both setups was that in Example 4, inlet tubes that had a certain bending were used for modelling of the mixing devices.

Example 6: Computational fluid dynamics (CFD) analysis of the T-piece connector and Y-piece connector (without tubing system): The inventors generated optimized mixing or swirling elements adapted from T-piece elements by introducing at least one bend in the inlet ports and/or the outlet port. Several different models were designed and used for CFD simulations (see Figure 5).

In the computational model, the physical characteristics of the RNA solution were assigned with a density of 997.9kg/m³ and a kinematic viscosity of 2.39mm²/s and the physical characteristics of the protamine-trehalose solution were assigned with a density of 1039.4kg/m³ and a kinematic viscosity of 1.206mm²/s. The CFD analysis was performed for different optimized mixing devices, comprising at least one bend in the inlet ports (see Figure 5). The surface uniformity at 760ml/min flow rate was determined according to the volume fraction of the protamine/trehalose solution at the outlet port of each mixing device design. Using this method, the homogeneity of the product liquid composition was simulated over time. Figure 6 shows an exemplary result of the CFD analysis performed according to Example 6. The graph shows the homogeneity/uniformity obtained at an outlet port after a certain time period. For the simulation, a mixing device according to Figure 5A was used. Moreover, a blend time was determined. The blend time was determined as the time point where the mixture of both solutions showed a constant homogeneity/uniformity of larger than 70%. The results of the CFD analysis are shown in Figures 6-9.

Results:

Figure 6 shows that the respective plane design (as illustrated in Figure 5A) having bends in the inlet ports and a straight outlet port, led to a homogeneity level of around 65%.

Figure 7 shows that the respective design (as illustrated in Figure 5B) having bends in the inlet ports and a straight outlet port, with additional bends in z-direction, led to a homogeneity level of around 65%.

Figure 8 shows that the respective design (as illustrated in Figure 5C) having bends in the inlet ports and a bends in the outlet port, led to a homogeneity level of around 80%. The time point, where the homogeneity constantly reached a value of larger than 0.7 (70%) is indicated with a dashed line. The mixing time was faster than 0.1 seconds. Compared to the T-piece connector static mixing device (cf. Figure 3), or the designs shown in Figure 5A and 5B, the mixing properties could be significantly improved.

Figure 9 shows that the respective design (as illustrated in Figure 5D) having bends in the inlet ports and a bends in the outlet port, and additional bends in z-direction, led to a homogeneity level of around 80%. The time point, where the homogeneity constantly reached a value of larger than 0.7 (70%) is indicated with a dashed line. The mixing time was faster than 0.1 seconds.

Summarizing the above results, the inventors found that the introduction of bends in the inlet port and the outlet port significantly improved the mixing properties of the element. Surprisingly the introduction of a bend in the outlet tube led to a further improvement of mixing (constant and higher degree of homogeneity, faster mixing time/blend time) which is a particular advantage (compare Figures 6 and 7 (embodiments without bend in the outlet tube) with Figures 8 and 9 (embodiments with bend in the outlet tube). Accordingly, the improved mixing properties of the inventive mixing elements generated monodisperse nucleic acid nanoparticles.

Example 7: Design of a GMP-compatible mixing device:

Based on the results of Example 6, the inventors designed a GMP-compatible setup for the scalable nucleic acid (RNA) nanoparticle formulation. The setup essentially consisted of a hose routing system, wherein the hose routing system was constructed to shape the tubes according to the model shown in Figure 5C. In that particular example, the hose routing 11 was integrated into a table 10 (via 3D printing technology). An illustration of the hose routing table is shown in Figure 10. For the formulation of nucleic acid nanoparticles, tubes are placed into the hose routing table to allow scalable and efficient nucleic acid nanoparticle formulation. The advantage of such a design is that the formulation can be performed in a regulated environment (e.g., GMP-grade tubing system can be used as single use element). Figure 11 shows a top view of an exemplary arrangement of a hose routing 11 with a (single use) tubing element 12 that is placed into a hose routing table 10. The flow of two solutions (first component, e.g. nucleic acid comprising solution (2) and second component, e.g. protamine/trehalose solution (3)) is controlled via a pumping element 4. The nanoparticle comprising product solution is captured via an outlet tube in a capture module, e.g. a vessel 7. Example 8: Design of a GMP-compatible and HT-compatible mixing device and HT-formulation of lipid nanoparticles

Based on the results of Example 6, the inventors designed a GMP-compatible and HT-compatible setup for the scalable and parallelizable RNA nanoparticle formulation. The setup essentially consists of an array of miniaturized mixing devices (see Figure 12 and Figure 13). The single mixing device may be generated e.g. via 3D printing, either designed with a screw element at the outlet port and/or inlet port (see Figure 12A) or directly manufactured to compromise a vial for collecting the formulated solution (see Figure 12B). The single mixing device may be arranged as multi-arrays (e.g., 6, 12, 24, 48, 96) to allow for a parallelized small-scale formulation of (different) nucleic acid nanoparticle comprising solutions (see Figure 13). The system allows for the parallel formulation of nucleic acid nanoparticle comprising solutions, particularly suitable for screening approaches or the parallel production of different nucleic acid nanoparticle comprising solutions under GMP conditions. The system as described in Figure 13 is used for parallel HT-formulation of LNP nanoparticles comprising RNA. Lipid nanoparticle (LNP)-complexed RNA is prepared using an ionizable amino lipid (cationic lipid), phospholipid, cholesterol and a PEGylated lipid.

Briefly, 48 different RNA constructs are diluted to a total concentration of 0.05 mg/mL in 50 mM citrate buffer, pH4 (first component). Cationic lipid, l,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol and PEG- lipid are solubilized in ethanol (second component).

The GMP-compatible and HT-compatible mixing device is used to mix the ethanolic lipid solution (second component) with the 48 different RNA solution (first component) at a ratio of about 1:6 to 1:2 (vol/vol) at flow rates of 2, 5, 20, 40, 60, 80, lOOmL/min. The resulting formulated 48 different LNP solutions are captured in a 48 well multi-array. Optionally, Ethanol is removed and the external buffer replaced with PBS by dialysis. Optionally, the lipid nanoparticles are filtered through a 0.2pm pore sterile filter. Lipid nanoparticle particle diameter size is determined by quasi-elastic light scattering using a Malvern Zetasizer Nano (Malvern Instruments Ltd, Malvern, UK).

Example 9: Experimental test of GMP-compatible mixing device

The aim of that experiment was to experimentally test the GMP-compatible mixing device as illustrated in Figure 11 for the formulation of RNA molecules with protamine. Three different RNA constructs were used for formulation (having different sizes and GC contents). In Addition, the results were compared to a T-piece connector mixing device as illustrated in Figure 1.

1. Description of the GMP compatible mixing device:

The GMP-compatible mixing device was assembled as illustrated in Figure 11. The hose-routing table 10 was manufactured using 3D printing. Tubes 12 were placed into the table 10 to form a hose routing 11. The flow of the two solutions was controlled using a peristaltic pump 4. The formulated solution was collected in a sterile corning bottle (capture vessel 7). The essential elements of the GMP-compatible mixing device were as follows:

Platinum Silicon Tubes 3.2 (Watson Marlow)

Peristaltic pump DU/RL (Watson Marlow)

T-piece (Merck)

- 50 ml and 250 ml corning bottle (VWR)

Hose routing table (3D manufactured)

2. Preparation of RNA-comprisina nanoparticles in the GMP-compatible mixing device:

The standard RNA solution (0.87g/L) and the protamine/trehalose standard solution (0.31g/L protamine; 10.87 % trehalose) prepared according to Example 1 were pumped into the mixing device with two different total flow rates (207 and 774ml/min). For the experiment, three different RNA constructs were used for formulation (R4032, 646bp size, 58.1% GC content (SEQ ID NO: 7); R4034, 1339bp size, 62.9% GC content (SEQ ID NO: 8); R4038, 1885bp size, 70.1% GC content (SEQ ID NO: 9). In addition, quality attributes of the obtained particles were characterized, including average particle sizes (zetasizer, Z-averages) and absorption at 350nm (A350), determined according to Example 2. The results of the experiment are shown and summarized in Table 3.

Table 3: Results of the experiment; Comparison of the T-piece connector static mixing device (according to Figure 1) and the GMP compatible mixing device (according to figure 11)

Results:

In all performed experiments, the inventors found that RNA nanoparticles smaller than 200nm in average were generated in clear dispersions, without causing increased precipitation (A350 <0.5). This confirmed that the T- piece connector mixing device works at higher flow rates. In addition, the results show that the improved GMP- compatible mixing device generates RNA nanoparticles of smaller sizes (compared to the T-piece connector mixing device) and less precipitation (reflected by lower A350 values). The obtained RNA nanoparticles are further characterized regarding their immunostimulatory properties (see Examples 12 and 13).

In summary, the results show that the GMP-compatible mixing device is suitable for the scalable industrial formulation of homogeneous solutions of nucleic acid comprising nanoparticles. Example 10: Experimental characterization of GMP-compatible mixing device

A GMP-compatible mixing setup according to Figure 11 was assembled and used for large-scale formulation of protamine RNA nanoparticles. The setup was characterized at different flow rates.

For experimental testing, a standard RNA solution (0.87g/L) and the protamine/trehalose standard solution (0.31g/L protamine; 10.87% trehalose) prepared according to Example 1 were pumped into the GMP- compatible mixing device (arrangement according to Figure 11) with different flow rates (conversion of pump rpm into flow rate provided in the Table 3) . For the experiment, three different RNA constructs (according to SEQ ID NOs: 7-9) were used for formulation. The quality of formulation/complexation was analyzed and particle size, PDI, and turbidity was determined as described in Example 1. The results of the experiment are shown in Figures 14-16. In Figures 14-16, panels on top show nanoparticles generated with RNA according to SEQ ID NO: 7; panels in the middle show nanoparticles generated with RNA according to SEQ ID NO: 8; and panels at the bottom show nanoparticles generated with RNA according to: SEQ ID NO: 9.

Table 3: Conversion of pump rpm into flow rate

Results:

Figure 14 shows that during formulation of all three RNA nanoparticles, particle sizes decreased with increasing complexation flow rate, an effect that leveled off at faster complexation flow rates. The particle size of the first measuring time point (0.0-2.5sec) is similar to the particle size of the later measuring time point (2.5-5.0sec) indicating that an instant, homogeneous formulation was obtained using the inventive mixing-device of the invention.

Figure 15 shows that the PDI values of all three RNA nanoparticles fluctuate between 0.2 and 0.0 with an average of 0.1, indicating a monodisperse, homogeneous particle size distribution.

Figure 16 shows that the turbidity of all three RNA nanoparticles is low and decreases with increasing complexation flow rate which seem to level off at about 0.08-0.1 (240rpm).

In summary, the results show that the GMP-compatible mixing device is suitable for the robust, scalable industrial formulation of high-quality homogeneous solutions of nucleic acid comprising nanoparticles. Notably, the results suggest that the GMP-compatible mixing device is also suitable for the formulation of other cationic peptide based or cationic polymer-based nucleic acid nanoparticles, e.g. using HO-PEG5000-S-(S- CHHHHHHRRRRHHHHHHC-S-)7-S-PEG5000-OH as a polymer. Example 11: Formulation of an immune stimulatory RNA nanoparticles ("RN Adjuvant")

The GMP-compatible mixing device of the invention (arranged in a setup illustrated in Figure 11) is used for large-scale formulation of immune stimulatory RNA nanoparticles ("RNAdjuvant"). As first component, an RNA solution comprising RNA according to SEQ ID NO: 3 or an RNA solution comprising RNA according to SEQ ID NO: 4 are used. As second component, a solution comprising cationic peptides Cys-Argl2-Cys or a solution comprising cationic Cys-Argl2 are used.

For synthesis of immune stimulatory RNA complex, the specified amount of the first component and the respective second component are pumped into the GMP-compatible mixing device (arrangement according to Figure 11) with different flow rates (see Table 3) in mass ratios of peptide:RNA 1:3.7. The quality of nanoparticles is analyzed and particle size, PDI, and turbidity are determined as described in Example 1.

Following that, the immunostimulatory property of the obtained immune stimulatory RNA nanoparticles is analyzed using a PBMC cell based assay according to Example 12.

Example 12: Stimulation of cytokines in peripheral blood mononuclear cells

In this test of immunostimulation, the dispersions comprising antigen mRNA-protamine nanoparticles obtained in Example 9 or RNAdjuvant nanoparticles obtained in Example 11 are used.

The obtained antigen mRNA nanoparticles are complexed with protamine prior to use in the experiments. The mRNA formulation consists of a mixture of 50% free mRNA and 50% complexed RNA at a weight ratio of 2: 1. The final concentration of the vaccine is adjusted with Ringer's lactate solution. RNAdjuvant nanoparticles are used without addition of free RNA.

The samples are lyophilized (Christ Alpha I) and reconstituted in Ringer lactate (in the volume of the sample before lyophilization). Peripheral blood mononuclear cells (PBMCs) from healthy human subjects are isolated by density gradient centrifugation and aliquots are cryopreserved in liquid nitrogen. On the day of the stimulation, PBMCs are thawed and 2x105 cells seeded in each well of a 96 flat bottom plate in 200ul X-Vivo 15 serum-free medium supplemented with 100 IU/ml penicillin/streptomycin (both Lonza). Cells are stimulated with the respective formulations (RNAdjuvant or mRNA formulation). Untreated cells are used as control. After 24 hours, cell-free supernatants are collected and the concentrations of TNF, IFN-a and IL-12p70 are measured by Cytometric Bead Array (CBA) according to manufacturer's instructions (BD Biosciences). Samples are acquired on a BD FACS CantoTM (BD Biosciences) and the data is analyzed using the FCAP Array v3.0 software (BD Biosciences). Example 13: In vivo testing of the obtained RNA nanoparticles 1, Vaccination

Female BALB/c mice are injected intradermal^ (i.d.) and intramuscularly (i.m.) with 30ug formulated RNA vaccine (obtained in Example 9 and Example 10). Control mice are injected intradermal^ with buffer (Ringer- lactate). Vaccination comprises five immunizations with 2 immunizations per week. The immune response is analysed 5 or 6 days after completion of the vaccination cycle.

2. ELISPOT - Detection of CTL (cytotoxic T cell) responses

For the detection of CTL (cytotoxic T cell) responses the analysis of IFN-gamma secretion in response to a specific stimulus can be visualized at a single cell level using the ELISPOT technique. Splenocytes from mice vaccinated with the mRNA vaccine as described above and control mice are isolated 6 days after the last vaccination and then transferred into 96-well ELISPOT plates coated with an alphalFN-gamma capture antibody. The cells are then stimulated for 24 hours at 37°C using respective capture peptides for each antigen.

After the incubation period the cells are washed out of the plate and the IFN-gamma secreted by the cells is detected using a biotinylated secondary antibody against murine IFN-gamma, followed by streptavidin-AKP. Spots are visualized using BCIP/NBT substrate and counted using an automated ELISPOT reader (Immunospot Analyzer, CTL Analyzers LLC).

Claims

C L A I M S

A mixing device (20) for the production of a liquid nucleic acid composition, wherein the mixing device (20) comprises:

a first inlet tube (8a) for a first component (2) comprising a nucleic acid,

a second inlet tube (8b) for a second component (3),

a connecting element (1), and

an outlet tube (9),

wherein the connecting element (1) is configured to connect the first inlet tube (8a) and the second inlet tube (8b) to the outlet tube (9),

wherein the outlet tube (9) comprises a bend or a baffle as swirling element configured to introduce a swirling of the first component (2) and the second component (3) in the outlet tube (9) to allow a mixing of the first component (2) and the second component (3) to produce the liquid nucleic acid composition, and

wherein the bend bends between 45° and 135° relative to the outlet tube (9).

2. Mixing device (20) according to claim 1, wherein the first inlet tube (8a) and/or the second inlet tube (8b) comprises a swirling element as defined in claim 1.

3. Mixing device (20) according to claim 1, wherein only the outlet tube (9) comprises a swirling element as defined in claim 1.

4. Mixing device (20) according to one of the preceding claims, wherein the bend bends between 80° and 100° relative to the respective tube.

5. Mixing device (20) according to one of the preceding claims, wherein the bend comprises at least two curves.

6. Mixing device (20) according to the preceding claim, wherein the at least two curves are antidromic curved.

7. Mixing device (20) according to one of the preceding claims, wherein the bend has an S-shape or Z- shape.

8. Mixing device (20) according to one of the preceding claims, wherein the bend lies in the plane of the respective tube.

9. Mixing device (20) according to one of the claims 1 to 7, wherein the bend protrudes out of the plane of the respective tube.

10. Mixing device (20) according to the preceding claim, wherein the bend protrudes essentially perpendicular out of the plane of the respective tube.

11. Mixing device (20) according to one of the preceding claims, wherein the connecting element (1) is static.

12. Mixing device (20) according to one of the preceding claims, wherein the connecting element (1) has a T-shape or a Y-shape.

13. Mixing device (20) according to one of the preceding claims, wherein the second component (3) is liquid.

14. Mixing device (20) according to one of the preceding claims, wherein the second component (3) comprises a complexation partner.

15. Mixing device (20) according to the preceding claim, wherein the second component comprises a lyoprotectant.

16. Mixing device (20) according to the preceding claim, wherein the lyoprotectant is trehalose.

17. Mixing device (20) according to claim 14, wherein the complexation partner is cationic or polycationic.

18. Mixing device (20) according to claim 14 or 17, wherein the complexation partner comprises a cationic or polycationic peptide or protein.

19. Mixing device (20) according to claim 18, wherein the cationic or polycationic peptide or protein is protamine.

20. Mixing device (20) according to claim 18, wherein the cationic or polycationic peptide or protein is selected from the group consisting of SEQ ID NOs. 10 to 13.

21. Mixing device (20) according to one of claims 1 to 14, wherein the second component (3) is a polymeric carrier molecule.

22. Mixing device (20) according to claim 21, wherein the polymeric carrier molecule comprises the amino acid sequence according to SEQ ID NOs. 10 to 13.

23. Mixing device (20) according to one of claims 1 to 14, wherein the second component (3) comprises at least one cationic or ionizable lipid suitable to form lipid nanoparticles.

24. Mixing device (20) according to one of the preceding claims, wherein the liquid nucleic acid composition comprises at least a nanoparticle comprising the nucleic acid of the first component (2) and the complexation partner of the second component (3).

25. Mixing device (20) according to one of the preceding claims, further comprising a pumping element configured to pump the first component (2) and the second component (3) into the connecting element (!)■

26. Mixing device (20) according to the preceding claim, wherein the pumping element is configured to pump the first component (2) and the second component (3) with different flow rates.

27. Mixing device (20) according to claim 25 or 26, wherein the pumping element comprises at least a peristaltic pump.

28. Mixing device (20) according to one of the preceding claims, further comprising a first container configured to contain the first component (2), a second container configured to contain the second component (3) and/or an outlet container configured to contain the liquid nucleic acid composition.

29. Mixing device (20) according to one of the preceding claims, wherein a flow rate of the nucleic acid composition is between 200 and 1000 ml/min and in particular between 400 and 800 ml/min.

30. Mixing device (20) according to one of the preceding claims, wherein a blend time for the mixing of the first component (2) and the second component (3) up to at least 70 % homogeneity is between 0.05 and 1 s, preferably between 0.1 and 0.5 s and more preferably between 0.1 and 0.15 s.

31. Mixing device (20) according to one of the preceding claims, wherein the mixing device (20) is at least partially manufactured out of one of a group comprising silicone, PET, and stainless steel.

32. A hose routing (11) comprising a mixing device (20) according to one of the preceding claims, wherein the mixing device (20) is integrated into a table element (10).

33. A mixing array (30), comprising a plurality of mixing devices (20) according to one of the preceding claims.

34. Mixing array (30) according to the preceding claim, wherein the mixing array (30) comprises 6, 12, 24, 48 or 96 mixing devices (20) and is configured to produce different nucleic acid compositions simultaneously.

35. Mixing array (30) according to the preceding claim, wherein the different nucleic acid compositions differ from each other in the first component (2) and/or the second component (3).

36. A method for the production of a liquid nucleic acid composition, wherein the method comprises the following steps:

providing a first component (2) of the composition by a first inlet tube (8a), wherein the first component (2) comprises a liquid nucleic acid,

providing a second component (3) of the composition by a second inlet tube (8b), guiding the first component (2) and the second component (3) to an outlet tube (9), and introducing a swirling of the first component (2) and the second component (3) in the outlet tube (9) by means of a bend or a baffle to allow a mixing of the first component (2) and the second component (3) to produce the liquid nucleic acid composition, wherein the bend bends between 45° and 135° relative to the outlet tube (9).

Method according to the preceding claim, wherein the liquid nucleic acid composition comprises at least a nanoparticle comprising the nucleic acid of the first component (2) and a complexation partner of the second component (3).

Method according to the preceding claims, wherein the nanoparticle has a particle size between 50 and 200 nm, and in particular between 50 and 150 nm.

Method according to one of the preceding claims, wherein the nucleic acid isRNA and in particular mRNA.

Method according to the preceding claim, wherein RNA is in a concentration of from 0.1 to 20 g/L, preferably from 0.5 to 10 g/L, and more preferably from 0.5 to 7 g/L.

Method according to claim 37, wherein the complexation partner comprises a cationic or polycationic compound, preferably as defined in Claim 17 to 23, in a concentration in a range from 0.05 to 10.00 g/L, preferably from 0.10 to 5.00 g/L or, more preferably, from 0.10 to 1.00 g/L.

Use of a mixing device (20), hose routing (11) or mixing array (30) according to one of the claims 1 to 35 in a method according to one of the claims 36 to 41.

Use of a mixing device (20), hose routing (11) or mixing array (30) according to one of the claims 1 to 35 in a method for producing a medicament or a vaccine or an adjuvant containing the liquid nucleic acid composition.

Use of a mixing device (20), hose routing (11) or mixing array (30) according to one of the claims 1 to 35 for high throughput production and/or screening of liquid nucleic acid compositions.