Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D487/00—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00
  • C07D487/22—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00 in which the condensed system contains four or more hetero rings
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D471/00—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, at least one ring being a six-membered ring with one nitrogen atom, not provided for by groups C07D451/00 - C07D463/00
  • C07D471/22—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, at least one ring being a six-membered ring with one nitrogen atom, not provided for by groups C07D451/00 - C07D463/00 in which the condensed systems contains four or more hetero rings
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
  • C07H13/00—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids
  • C07H13/02—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids by carboxylic acids
  • C07H13/08—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids by carboxylic acids having the esterifying carboxyl radicals directly attached to carbocyclic rings

Definitions

• Nanoscience is being developed in conjunction with advanced medical science for further precision in diagnosis and treatment.
• Multidisciplinary biomedical scientific teams including biologists, physicians, mathematicians, engineers and clinicians are working to gather information about the physical properties of intracellular structures upon which biology's molecular machines are built.
• a new emphasis is being given to moving medical science from laboratory to the bedside and the community.
• This platform development program brings together an outstanding laboratory that is pioneering biomedical applications of PAA nanoparticles, e.g.
• polyacrylic acid and its derivatives of the polyacrylic acid carboxy group such as polyacrylamide (Kopelman)
• Kopelman polyacrylamide
• an innovative porphyrin chemistry and a world-class PDT (photodynamic therapy) group at RPCI that is highly experienced in the high volume screening and in vitro/in vivo evaluation of novel compounds, and in developing new therapies from the test tube to FDA approval for clinical use.
• nanoplatforms and nano vectors i.e. a nanoplatform that delivers a therapeutic or imaging agent
• biomedical applications show enormous promise for cancer diagnosis and therapy. The approach has been the subject of several recent reviews.
• Therapeutic examples include nanoparticles (NPs) containing PDT agents, folate receptor-targeted, boron containing dendrimers for neutron capture and NP-directed thermal therapy. Recently, therapeutic and imaging potential of encapsulated, post-loaded and covalently linked photosensitizer-NPs have been evaluated. In PAA NP the post-loading efficiency showed enhanced in vitro/in vivo therapeutic and imaging potential.
• PAA NP have core matrixes that can readily incorporate molecular or small NP payloads, and can be prepared in 10-150 nm sizes, with good control of size distributions. The surfaces of NPs can be readily functionalized, to permit attachment of targeting ligands, and both are stable to singlet oxygen (102) produced during PDT.
• PAA-NP have the advantages of (1) A relatively large knowledge base on cancer imaging, PDT, chemical sensing, stability and biodegradation. (2) No known in-vivo toxicity. (3) Long plasma circulation time without surface modification, but with biodegradation and bioelimination rates controllable via the type and amount of selective cross-linking (introduced during polymerization inside reverse micelles). (4) Scale-up to 400g material has been demonstrated, as well as storage stability over extended periods. Limitations include relative difficulty in incorporating hydrophobic compounds (although we have accomplished this), leaching of small hydrophilic components unless they are "anchored", and unknown limitation on bulk tumor permeability because of hydrogel swelling.
• PDT is a clinically effective and still evolving locally selective therapy for cancers.
• the utility of PDT has been demonstrated with various photosensitizers for multiple types of disease. It is FDA approved for early and late stage lung cancer, obstructive esophageal cancer, high-grade dysplasia associated with Barrett's esophagus, age-related macular degeneration and actinic keratoses.
• PDT employs tumor localizing PSs that produce reactive I O2 (singet oxygen) upon absorption of light which is responsible for the destruction of the tumor.
• oxidation-reduction reactions also can produce superoxide anions, hydrogen peroxide and hydroxyl radicals which contribute to tumor ablation.
• Photosensitizers have been designed which localize relatively specifically to certain subcellular structures such as mitochondria, which are highly sensitive targets.
• direct photodynamic tumor cell kill, destruction of the tumor supporting vasculature and possibly activation of the innate and adaptive anti-tumor immune system interact to destroy the malignant tissue.
• the preferential killing of the targeted cells e.g. tumor
• adjacent normal tissues is essential for PDT, and the preferential target damage achieved in clinical applications is a major driving force behind the use of the modality.
• Tetrapyrrolic photosensitizers used in accordance with the present invention are based upon the tetrapyrrolic structure shown below:
• IUPAC NOMENCLATURE The penetration of light through tissue increases as its wavelength increases between 630 and 800 nm. Once light has penetrated tissue more than 2-3 mm it becomes fully diffuse (i.e. non-directional). In diffusion theory, the probability that a photon will penetrate a given distance into tissue is governed by the probability per unit path. The intrinsic absorption of most tissues is dominated by hemoglobin and deoxyhemoglobin, with the strong peaks of the absorption bands at wavelengths shorter than 630 nm. The tails of these bands extend beyond 630 nm and grow weaker with increasing wavelength.
• Tetrapyrollic photosensitizers have several very desirable properties as therapeutic agents deliverable by NP: (1) Often only a very small fraction of administered targeted drug makes it to tumor sites and the remainder can cause systemic toxicity.
• tetrapyrrolic PDT provides dual selectivity in that the PS is inactive in the absence of light and is innocuous without photoactivation. Thus the PS contained by the NP can be locally activated at the site of disease. (2) PDT effects are due to production of 102, which can readily diffuse from the pores of the NP. Thus, in contrast to usual chemotherapeutic agents, release of encapsulated drug from the NP, is not necessary. Instead, stable NP with long plasma residence times can be used, which increases the amount of drug delivered to the tumors.
• NP platforms also provide significant advantages for PDT: (1) High levels of imaging agents can be combined with the PS in the NP permitting a "see and treat" approach, with fluorescence image guided placement of optical fibers to direct the photoactivating light to large or subsurface tumors, or to early non clinically evident disease. (2) It is also possible to add targeting moieties, such as cRGD or F3 peptide to the NP so as to increase the selective delivery of the PS. (3) The NP can carry large numbers of PS, and their surface can be modified to provide the desired hydrophilicity for optimal plasma pharmacokinetics. Thus, they can deliver high levels of PS to tumors, reducing the amount of light necessary for tumor cure.
• Optical imaging includes measurement of absorption of endogenous molecules (e. g. hemoglobin) or administered dyes, detection of bioluminescence in preclinical models, and detection of fluorescence from endogenous fluorophores or from targeted exogenous molecules. Fluorescence, the emission of absorbed light at a longer wavelength, can be highly sensitive: a typical cyanine dye with a lifetime of 0.6 nsec can emit up to 1032 photons/second/mole. A sensitive optical detector can image ⁇ 103 photons/second. Thus even with low excitation power, low levels of fluorescent molecular beacons can be detected.
• ICG isocyanine green dye
• Multiple approaches have been employed to improve optical probelocalization, including administering it in a quenched form that is activated within tumors, or coupling it to antibodies or small molecules such as receptor ligands.
• Recent studies have focused on developing dye conjugates of small bioactive molecules, to improve rapid diffusion to target tissue and use combinatorial and high throughput strategies to identify, optimize, and enhance in vivo stability of the new probes.
• Some peptide analogs of ICG derivatives have moderate tumor specificity and are entering pre-clinical studies. However, none of these compounds are designed for both tumor detection and therapy. It is important to develop targeting strategies that cope with the heterogeneity of tumors in vivo, where there are inconsistent and varying expressions of targetable sites.
• PS Photosensitizers
• PS generally fluoresce and their fluorescence properties in vivo has been exploited for the detection of early-stage cancers in the lung, bladder and other sites 17
• the fluorescence can be used to guide the activating light.
• PS are not optimal fluorophores for tumor detection for several reasons: (i) They have low fluorescence quantum yields (especially the long wavelength photosensitizers related to bacteriochlorins). Efficient PS tend to have lower fluorescence efficiency (quantum yield) than compounds designed to be fluorophores, such as cyanine dyes because the excited singlet state energy emitted as fluorescence is instead transferred to the triplet state and then to molecular oxygen .
• Porphyrin-based PS have small Stokes shifts. Porphyrin-based PS have a relatively small difference between the long wavelength absorption band and the fluorescence wavelength (Stokes shift), which makes it technically difficult to separate the fluorescence from the excitation wavelength, (iii) Most PS have relatively short fluorescent wavelengths, ⁇ 800 nm, which are not optimal for detection deep in tissues.
• a photosensitizer (PS) with increased selectivity and longer wavelength could be a more suitable candidate for brain and deeply seated tumors (especially breast, brain and lung).
• PDT photodynamic therapy
• Chang et al reported an effective radius of tumor cell kill in 22 glioma patients of 8 mm compared with the 1.5 cm depth of necrosis noted by Pierria with the intracavitary illumination method. It is believed that tumor resection is important so that the numbers of tumor cells remaining to treat are minimized. With stereotactic implantation of fibers for interstitial PDT there is no cavity to accommodate swelling and a considerable volume of necrotic tumor which causes cerebral edema. However, cerebral edema can be readily controlled with steroid therapy. Compared to chemotherapy and radiotherapy, patients with brain tumors treated with PDT have definitely shown long-term survival, whereas glioma patients treated with adjuvant chemotherapy or radiotherapy do not show additional benefits as reported by Kostron et al. and Kaye et al. On the basis of our preliminary data, the ⁇ 3 targeted NPs may improve tumor-selectivity and PDT outcome.
• CT Computed Tomography
• MRI Magnetic Resonance Imaging
• intraoperative ultrasound can provide real-time information to locate the tumor and define its volume.
• Intraoperative MRI allows the neurosurgeon to obtain images during surgery, which can improve the completeness of the tumor resection, however microscopic disease is still not detected.
• the surgeon would perform the brain tumor resection with continuous guidance from high-contrast fluorescence from the tumor observed directly in the resection cavity.
• the present invention relates to a novel tetrapyrrolic photosensitizer having a substituent attached through carbon atom 20 between the A and D rings of the basic tetrapyrrolic structure and further relates to PAA nanoparticles containing a photosensitizer conjugated with a PAA nanoparticle through carbon atom 20 between the A and D rings of the basic tetrapyrrolic structure and an imaging enhancing agent also containing a fluorescent imaging agent.
• the preferred fluorescent imaging agent is a cyanine dye.
• the photosensitizer is preferably a tetrapyrrolic photosensitizer having the structural formula:
• Ri is hydrogen or lower alkyl of 1 through 8 carbon atoms
• X is an aryl or heteroaryl group
• n is an integer of 0 to 6;
• R2 0 is lower alkyl of 1 through 8 carbon atoms,or 3,5-bis(trifluoromethyl)-benzyl
• Ri a and R2 a are each independently hydrogen or lower alkyl of 1 through 8 carbon atoms, or together form a covalent bond;
• R 3 and R4 are each independently hydrogen or lower alkyl of 1 through 8 carbon atoms;
• R 3a and R4 a are each independently hydrogen or lower alkyl of 1 through 8 carbon atoms, or together form a covalent bond;
• R5 is hydrogen
• R 9 and Rio are each independently hydrogen, or lower alkyl of 1 through 8 carbon atoms and R 9 may be -CH2CH2COOR 2 where R 2 is an alkyl group that may optionally substituted with one or more fluorine atoms;
• R11 is phenyl
• the photosensitizer may be conjugated with an image enhancing agent prior to incorporation into the nanoparticle, after incorporation into the nanoparticle or the photosensitizer and/or image enhancing agent may chemically bound to the nanoparticle and/or one or more of the photosensitizer and image enhancing agent may be physically bound to the nanoparticle.
• Imaging enhancing agents may be for essentially any imaging process, e.g. examples of such imaging enhancing agents are discussed in the background of the invention previously discussed and in the list of references incorporated by reference herein as background art.
• Figure 1 shows a structural formula for 17-benzoic acid HPPH analog (PS815) having a substituent at the " 17" carbon atom on the D ring suitable for conjugation with a PAA nanoparticle and showing such a conjugation through an amide link.
• PS815 17-benzoic acid HPPH analog
• Figure 2 shows a structural formula for 20-benzoic acid HPPH methyl ester analog (PS812) having a substituent at the "20" carbon atom between the A and D rings on the base ring of the tetrapyrrolic structure for conjugation with a PAA nanoparticle and showing such a conjugation through an amide link.
• PS812 20-benzoic acid HPPH methyl ester analog
• Figure 3 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS815 vs. PS815 conjugated to PAA nanoparticle vs. PS815 both conjugated and post-loaded on PAA nanoparticle without light treatment.
• Figure 4 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS815 vs. PS815 conjugated to PAA nanoparticle vs. PS815 both conjugated and post-loaded on PAA nanoparticles. Light treatment was done at 0.25 Joules following 24h incubation in Colon 26 cells.
• Figure 5 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS815 vs. PS815 conjugated to PAA nanoparticle vs. PS815 both conjugated and post-loaded on PAA nanoparticles. Light treatment was done at 0.5 Joules following 24h incubation in Colon 26 cells.
• Figure 6 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS815 vs. PS815 conjugated to PAA nanoparticle vs.PS815 both conjugated and post-loaded on PAA nanoparticles. Light treatment was done at one Joule following 24h incubation in Colon 26 cells.
• Figure 7 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS815 vs. PS815 conjugated to PAA nanoparticle vs. PS815 both conjugated and post-loaded on PAA nanoparticles. Light treatment was done at 2 Joules following 24h incubation in Colon 26 cells.
• Figure 8 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS812 of the invention vs. PS812 conjugated to PAA nanoparticle vs. PS812 both conjugated and post-loaded on PAA nanoparticles without light treatment.
• Figure 9 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS812 of the invention vs. PS812 conjugated to PAA nanoparticle vs. PS812 both conjugated and post-loaded on PAA nanoparticles.
• Light treatment was done at 0.5 Joules following 24h incubation in Colon 26 cells.
• Figure 10 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS812 of the invention vs. PS812 conjugated to PAA nanoparticle vs. PS812 both conjugated and post-loaded on PAA nanoparticles. Light treatment was done at 0.5 Joule following 24h incubation in Colon 26 cells.
• Figure 1 1 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS812 of the invention vs. PS812 conjugated to PAA nanoparticle vs. PS812 both conjugated and post-loaded on PAA nanoparticles. Light treatment was done at one Joule following 24h incubation in Colon 26 cells.
• Figure 12 is a graph showing percent survival of Colon 26 cancer cells relative to concentration in the form of MTT Assay of compound PS812 of the invention vs. PS812 conjugated to PAA nanoparticle vs. PS812 both conjugated and post-loaded on PAA nanoparticles. Light treatment was done at 2 Joules following 24h incubation in Colon 26 cells.
• Figure 13 is a bar graph showing that the superior treatment and imaging activity of PS812 conjugated to PAA nanoparticles surprisingly occurs despite lower accumulation of the material in the cells.
• Figure 14 shows a series of A through E fluorescent images, using a Maestro GNIR-Flex TM in vivo imaging system, at 4, 8, 12, 24 and 48 hours post i.v. 0.47 mmoles kg injection of Balb/c mice having an induced COLO-26 tumor,
• the excitation wave length was 575-605 nm and emission wave length was 645 nm long pass.
• the images were originally color enhanced by computer assignment of color depth relative to fluorescent intensity. Exposure was 100ms (fluorescenceO and 8 ms 9white light).
• the injected material used was PS 812-ME, neither conjugated nor post loaded on nanoparticles.
• the grey zone is a mouse and the darker grey ovoid area is the tumor.
• Figure 15 shows a series of A through E fluorescent images, using a Maestro GNIR-Flex TM in vivo imaging system, at 4, 8, 12, 24 and 48 hours post i.v. 0.47 mmoles/kg injection of Balb/c mice having an induced COLO-26 tumor,
• the excitation wave length was 575-605 nm and emission wave length was 645 nm long pass.
• the images were originally color enhanced by computer assignment of color depth relative to fluorescent intensity. Exposure was 100ms (fluorescence and 8 ms (white light)
• the injected material used was PS 812-Me (compound 12) conjugated to PAA nanoparticles as shown in Figure 2. Image clarity and definition relative to unconjugated PS812Me was clearly apparent. In the greyscale images, the grey zone is a mouse and the darker grey ovoid area is the tumor.
• Figure 16 shows a series of A through D fluorescent images, using a Maestro GNIR-Flex TM in vivo imaging system, at 4, 10, 24 and 48 hours post i.v. 0.47 mmoles/kg injection of Balb/c mice having an induced COLO-26 tumor,
• the excitation wave length was 575-605 nm and emission wave length was 645 nm long pass.
• the images were originally color enhanced by computer assignment of color depth relative to fluorescent intensity. Exposure was 100ms (fluorescence and 8 ms (white light)
• the injected material used was PS 812-Me (compound 12) conjugated to PAA nanoparticles as shown in Figure 2 and cyanine dye (CD) conjugated to PAA nanoparticles..
• Figure 17 shows a series of A through D fluorescent images, using a Maestro GNIR-Flex TM in vivo imaging system, at 4, 10, 24 and 48 hours post i.v. 0.47 mmoles/kg injection of Balb/c mice having an induced COLO-26 tumor,
• the excitation wave length was 575-605 nm and emission wave length was 645 nm long pass.
• the images were originally color enhanced by computer assignment of color depth relative to fluorescent intensity. Exposure was 100ms (fluorescence and 8 ms (white light)
• the injected material used was PS 815 (Figure 1) conjugated to PAA nanoparticles as shown in Figure 1 and cyanine dye (CD) conjugated to PAA nanoparticles.
• the inferior image was apparent relative to image clarity and definition relative to PS812-Me (compound 12) conjugated to PAA nanoparticles and relative to PS812 conjugated to PAA nanoparticles as shown in Figure 1 and cyanine dye (CD) conjugated to PAA nanoparticles.
• the grey zone is a mouse and the darker grey ovoid area is the tumor.
• Previous inventions illustrate the utility of PAA nanoparticles for enhanced uptake of the imaging and phototherapeutic agents in tumors.
• certain cyanine dyes with limited tumor-avidity but desired photophysical properties on conjugating at the periphery of the nanoparticles show excellent fluorescence imaging ability. This could be due to the EPR effect (enhanced permeability and retention) of the nanoparticles, where the leaky tumor vessels help in accumulating the 30-35 nm size of the nanoparticles to tumor.
• Synthesis of PS 815 is made by known procedures by reaction of the -
• Figure 3 shows an MTT assay of compound 815 vs. 815 conjugated to PAA (polyacrylamide) nanoparticles and post loaded, non conjugated on PAA nanoparticles.
• PAA polyacrylamide
• the MTT assay is a colorimetric assay for measuring the activity of cellular enzymes that reduce MTT to dye resulting in a purple color.
• the MTT assay is used to determine toxicity of substances to cells.
• Figure 13 shows that the superior treatment and imaging activity of PS812 conjugated to PAA nanoparticles surprisingly occurs despite lower accumulation of the material in the cells.
• Figures 14-17 show superiority of fluoresence imaging using PS812 compound of the invention.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Health & Medical Sciences (AREA)
• Biochemistry (AREA)
• Biotechnology (AREA)
• General Health & Medical Sciences (AREA)
• Genetics & Genomics (AREA)
• Molecular Biology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
• Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
• Medicines That Contain Protein Lipid Enzymes And Other Medicines (AREA)
• Nitrogen Condensed Heterocyclic Rings (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=49879012

Family Applications (1)

Country Status (4)

Cited By (3)

Families Citing this family (3)

Citations (3)

Family Cites Families (2)

• 2012
  • 2012-07-09 US US13/544,558 patent/US9045488B2/en not_active Expired - Fee Related
• 2013
  • 2013-06-19 WO PCT/US2013/046537 patent/WO2014011370A1/en not_active Ceased
  • 2013-06-19 EP EP13817588.0A patent/EP2870124A4/en not_active Withdrawn
  • 2013-06-19 IN IN209DEN2015 patent/IN2015DN00209A/en unknown

Patent Citations (3)

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events