AU2019407159A1 - Combination therapy with a Raf inhibitor and a CKD4/6 inhibitor for use in the treatment of cancer - Google Patents

Abstract

The present invention relates to a pharmaceutical combination comprising (a) a Raf inhibitor as defined herein, or a pharmaceutically acceptable salt thereof and (b) a CKD4/6 inhibitor, particularly ribociclib, particularly for use in the treatment of a proliferative disease, preferably melanoma or pancreatic ductal adenocarcinoma.

Description

COMBINATION THERAPY WITH A RAF INHIBITOR AND A CDK4/6 INHIBITOR

FOR USE IN THE TREATMENT OF CANCER

FIELD OF INVENTION

This invention relates to a pharmaceutical combination comprising (a) a Rat inhibitor which is the Compound of formula (I), as defined herein, or a pharmaceutically acceptable salt thereof, and (b) a CDK4/6 inhibitor, particularly ribociclib, or a pharmaceutically acceptable salt thereof.

This invention also relates to such combinations for use in the treatment of cancer; uses of such combinations for the preparation of a medicament for the treatment of cancer; methods of treating cancer, in a subject in need thereof comprising administering to said subject a jointly therapeutically effective amount of said combinations; use of such combinations for the treatment of cancer; and pharmaceutical compositions comprising such combinations.

This invention also relates to the Compound of formula (I), as defined herein, or a pharmaceutically acceptable salt thereof, for use in a combination therapy with a CDK4/6 inhibitor, particularly ribociclib, or a pharmaceutically acceptable salt thereof. There is also provided herein a CDK4/6 inhibitor, particularly ribociclib, or a pharmaceutically acceptable salt thereof, for use in a combination therapy with the Compound of formula (I), as defined herein, or a pharmaceutically acceptable salt thereof.

BACKGROUND OF THE INVENTION

More than 30% of human cancers harbor mutations in the Mitogen Activated Protein Kinase (MAPK) pathway, most prevalent of which are RAS or BRAF mutations. The MAPK pathway (also known as RAS/RAF/CDK4/6/ERK pathway) is a key signaling cascade that drives cell proliferation, differentiation, and survival. Dysregulation of this pathway underlies many instances of tumorigenesis including melanoma (Kirkwood et al, Clin Cancer Res 18(2) :555- 67, 2012). This pathway is comprised of the RAS small guanidine triphosphatase (GTPase), which, when activated, promotes the activation of the RAF family proteins (ARAF, BRAF and CRAF, also known as RAF1 ). Activated RAF proteins lead to the phosphorylation and activation of CDK4/61/2 proteins, which subsequently phosphorylate and activate extracellular signal-regulated kinases (ERKs). ERKs phosphorylate a variety of substrates, including multiple transcription factors, and regulate several key cellular activities, including proliferation, differentiation, migration, survival and angiogenesis. In addition,

RAS or BRAF mutations constitutively activate the Cyclin D-CDK4/6 complex, where they cooperate with CDK4 activation and lead to tumor progression (Chudnovsky Y et al 2005; Monahan KB et al 2010). There is a high frequency of activating mutations in proteins of the MAPK pathway in melanoma. RAS mutant melanoma shows aggressive behavior, with a high rate of liver and brain metastases already present at initial diagnosis (Bergamasco et al, Value in Health Journal 19 A347-A766, 2016), and, therefore, poor prognosis. Response to standard of care chemotherapy is very limited. A Phase 3 study demonstrated some benefit of the CDK4/6 inhibitor binimetinib as compared to standard of care chemotherapy with dacarbazine, e.g. improved overall response rate of 15 vs. 7%. 402 patients were randomly assigned in a 2:1 fashion. A median PFS of 2.8 (95% Cl: 2.8-3.6) vs. 1.5 (1 .5-1 .7), HR 0.62 (0.47-0.80) in favor of binimetinib has been observed. However, discontinuation rate as a result of adverse events suspected to be related to study drug was high (20% vs. 5%), and the benefit in PFS did not transfer into improvements in overall survival (1 1.0 (95% Cl: 8.9-13.6) vs. 10.1 (7.0- 16.5) months (Dummer et al, Lancet Oncol 18(4):435-445, 2017).

The NRAS gene is mutated in 15-20% of melanomas - a relatively common subtype of melanoma. In melanoma, the majority of activating variants in NRAS occur at codon 61 , with variants at codons 12 and 13 occurring less frequently (Gao et al, Sci Signal, 2013; van Elsas, Recent Results Cancer Res, 1995). The presence of NRAS mutations in melanoma causes a switch in MAPK signaling from BRAF to CRAF, initiating dysregulated cAMP signaling that allows CRAF to signal to CDK4/6 (Dumaz 2006). Mutations in NRAS are exclusive of alterations in PTEN, implying that mutations in NRAS alone may activate signaling through both the MAPK and PI3K pathways (Goel et al, J Invest Dermatol 6(269):pl1 , 2006, Davies et al, Clin Cancer Res 15(24): 7538-46, 2009). Compared to other melanoma subtypes, melanomas with NRAS mutations are associated with a worse prognosis (Devitt et al, Pigment Cell Melanoma Res 24(4): 666-72, 201 1 ), and responses to standard of care chemotherapy are very limited.

KRAS mutations are frequently found in pancreatic cancer (di Magliano MP & Logsdon CD, Gastroenterology 2013; 144(6): 1220-9). A study on PDAC patient samples showed that 93% of all samples had KRAS mutations (Biankin et al. Nature 2012; 491 , 399^05). KRAS has the same downstream effectors as NRAS. However, there remains a high unmet medical need in both NRAS and KRAS-mutant cancers.

Selective pharmacological inhibition of NRAS remains technically challenging because its GTPase activity has so far eluded the successful design of specific small-molecule antagonists. Munoz-Couselo E, et al, OncoTargets and Therapy, 2017:10 Pages 3941 -3947 suggest that combinations with MEK inhibitors and immunotherapy are the most promising strategy. However, the efficacy of current approaches is not yet established.

It was recently reported that LY3009120, a pan-Raf inhibitor in combination with

abemaciclib, a CDK4/6 inhibitor, inhibited proliferation of certain tumor cells with KRAS or BRAF mutations (Chen SH et al, Oncogene, 2018, 37, 821 -832). However, LY3009120 inhibits several other kinases, including those that have important roles in cancer such as Ephrin receptors, JNK and SRC family members, thus potentially leading to off-target toxicities.

Effective therapies targeting RAS mutant cancers, including NRAS mutant melanoma and KRAS pancreatic ductal adenocarcinoma (PDAC), therefore remain an unmet medical need.

SUMMARY OF THE INVENTION

It has been found that the CDK4/6 inhibitor ribociclib in combination with a selective Raf inhibitor such as a Compound of formula (I) synergistically inhibited tumor cells in vitro. The combination also led to significant tumor regression in patient derived melanoma xenografts, particularly NRAS mutant melanoma xenografts, and to increased median percent survival in preclinical models.

The combined treatment of the Compound of formula (I) and ribociclib was well tolerated and led to increased anti-tumor activity compared to single agents in the patient derived tumor xenografts. These data indicate that the combination activity of the Compound of formula (I) and ribociclib may achieve greater and more durable responses in patients suffering from RAS mutant cancer (such as melanoma) in particular NRAS mutant cancer, more specifically NRAS mutant melanoma. Importantly, the same doses that evoke very little effect when the Compound of formula (I) and ribociclib are used as single agents, evoke a large effect when both agents are combined.

Thus the combination of the Compound of formula (I) and a CDK4/6 inhibitor, particularly ribociclib, or a pharmaceutically active salt thereof, may achieve greater and more durable responses in patients with activated MAPK pathway, in particular, NRAS-mutant cancer, such as NRAS-mutant melanoma or KRAS-mutant cancer such as KRAS-mutant pancreatic ductal adenocarcinoma (PDAC). The combination therapy may also provide fewer side- effects and/or be more tolerable for patients in need thereof.

The Compound of formula (I), a selective Raf inhibitor, with the CDK4/6 inhibitor ribociclib may also optimize suppression of MAPK signaling in NRAS mutant melanoma. The

Compound of formula (I) and ribociclib in combination may also help to prevent the emergence of resistance to the combination of BRAF and CDK4/6 (mitogen-activated protein kinase kinase) inhibitors in NRAS mutant melanoma or KRAS mutant PDAC.

No targeted therapies are currently available outside clinical studies for patients with NRAS mutant melanomas. The synergistic combination of a Raf inhibitor and a CDK4/6 inhibitor may exert strong clinical benefit in patients suffering from NRAS mutant cancer, and in particular NRAS mutant melanoma.

The invention therefore provides a pharmaceutical combination of a Raf inhibitor and a CDK4/6 inhibitor, wherein the Raf inhibitor is the Compound of formula (I),

or a pharmaceutically acceptable salt thereof.

In another aspect, the invention provides a pharmaceutical combination of a Raf inhibitor and a CDK4/6 inhibitor, wherein the CDK4/6 inhibitor is ribociclib, or a pharmaceutically acceptable salt thereof.

In another aspect, the invention provides a pharmaceutical combination of a Raf inhibitor and a CDK4/6 inhibitor, wherein

(i) the Raf inhibitor is the Compound of formula (I), or a pharmaceutically acceptable salt thereof; and

(ii) the CDK4/6 inhibitor is ribociclib, or a pharmaceutically acceptable salt thereof. In another aspect, the invention provides these pharmaceutical combinations for use in the treatment of cancer.

The present invention is particularly related to the combination of the invention for use in the treatment of a cancer which is characterized by activating mutations in the MAPK pathway, and in particular by one or more mutations in NRAS or KRAS. In particular, the combination of the invention may be useful for the treatment of melanoma, particularly, NRAS-mutant melanoma. Further, the combination of the invention may be useful for the treatment of pancreatic cancer, particularly, KRAS-mutant PDAC.

The present invention provides the Compound of formula (I) for use in treating cancer by co administration with a CDK4/6 inhibitor, for example, ribociclib, or a pharmaceutically acceptable salt thereof.

The present invention also provides ribocicib, or a pharmaceutically acceptable salt thereof, for use in treating cancer by co-administration with the Compound of formula (I), or a pharmaceutically acceptable salt thereof.

In another aspect, the invention provides the use of the pharmaceutical combination of a Raf inhibitor which is the Compound of formula (I) and a CDK4/6 inhibitor for the preparation of a medicament for the treatment of cancer.

In another aspect, the invention provides a method for treating cancer in a subject in need thereof comprising administering to a subject in need thereof a therapeutically effective amount of a pharmaceutical combination of a Raf inhibitor which is the Compound of formula (I) and a CDK4/6 inhibitor.

The present invention also provides a method of treating a cancer comprising

simultaneously, separately or sequentially administering to a subject in need thereof a combination of the invention in a quantity which is jointly therapeutically effective against said cancer.

The present invention also provides a pharmaceutical composition or combined preparation comprising a quantity of the combination of the invention, which is jointly therapeutically effective against a cancer, and optionally at least one pharmaceutically acceptable carrier. The present invention also provides a combined preparation comprising (a) one or more dosage units of a Raf inhibitor selected from the group consisting of (i) Compound of formula (I), or a pharmaceutically acceptable salt thereof, and (b) one or more dosage units of a CDK4/6 inhibitor, preferably ribociclib, or a pharmaceutically acceptable salt thereof, for use in the treatment of cancer.

The present invention also provides a commercial package comprising as active ingredients a combination of the invention and instructions for simultaneous, separate or sequential administration of a combination of the invention to a patient in need thereof for use in the treatment of a cancer such as melanoma and in particular NRAS-mutant melanoma or pancreatic cancer such as KRAS-mutant PDAC.

Various aspects of the invention are described in further detail below. Additional definitions are set out throughout the specification.

BRIEF DESCRIPTION OF THE FIGURES

The Compound of formula (I) is also referred to herein as“LXH254” or as“NVP-LXH254”. Ribociclib is referred to herein as“LEE01 1” or as“NVP-LEE01 1

FIGURE 1 : Effect of a combination of the Compound of formula (I) and ribociclib on anti-proliferative and phopho-Rb suppression effects relative to single treatments in the SK-MEL-30 melanoma cell line

Shown in (FIGURE 1 a, FIGURE 1 b, FIGURE 1 c) are combination matrices for inhibition of proliferation (FIGURE 1 a), Loewe (ADD) excess inhibition (FIGURE 1 b), and Growth Inhibition (Gl) (FIGURE 1c) for ribociclib in combination with the Compound of formula (I) as measured by CyQUANT® Direct Cell Proliferation Assay in the SK-MEL-30 melanoma cell line that harbors co-incident mutations in NRAS (Q61 K) and BRAF (D287H). In all cases increasing concentrations of ribociclib are shown along the bottom row from left to right and increasing concentrations of the Compound of formula (I) along the leftmost column from bottom to top. All remaining points in the grid display the percent inhibition that results from a combination of the two inhibitors that corresponds to the single agent concentrations denoted on the two axes. The excess inhibition matrix displays the percent excess inhibition of the experimental values (left grid) over the predicted values from the Loewe dose additivity model, which predicts inhibition due to dose additivity alone (Lehar et. al., 2009). Positive numbers represent areas of increasing synergy, and negative numbers regions of antagonism. The Growth Inhibition (Gl) measure is based on normalizing the experimental inhibition measurements using an additional time-zero vehicle reference level (time point of drug-addition). The Gl measure results in effect values on two different linear normalization scale portions with a‘break point’ at the time-zero level (i.e. at Gl=100%). Gl values will be > 100% if the point of stasis is exceeded (Lehar et al. 2009). (FIGURE 1d) Western blot analysis of phosphorylated RB1 , CDK4/61/2, ERK1/2 and RSK3 following either single agent or combination treatments with ribociclib and the Compound of formula (I) in SK-MEL-20 cells. Drug treatments, including concentrations in nanomolar (nM) are noted above western blot images. The duration of drug treatment for all samples was 48 hours. The specific proteins being probed are noted to the right of each set of panels.

FIGURE 2: The combination of the Compound of formula (I) and ribociclib

demonstrate improved anti-proliferative and phopho-Rb suppression effects relative to single treatments in the IPC-298 melanoma cell line

Shown are antiproliferative effects (FIGURE 2a, FIGURE 2b, FIGURE 2c) and western analysis of key signaling protein (FIGURE 2d) in the NRAS mutant melanoma cell line IPC298 (NRASQ61 L). Experimental protocols and data points inFIGURE 2a, FIGURE 2b, FIGURE 2c are as described for FIGURE 1 above.

FIGURE 3: The combination of the Compound of formula (I) and ribociclib

demonstrate improved anti-proliferative and phopho-Rb suppression effects relative to single treatments in the Meljuso melanoma cell line

Shown are antiproliferative effects (FIGURE 3a, FIGURE 3b, and FIGURE 3c) and western analysis of key signaling protein (FIGURE 3d) in the NRAS mutant melanoma cell line Meljuso (NRASQ61 L). Experimental protocols and data points in FIGURE 3a, FIGURE 3b, and FIGURE 3c are as described for FIGURE 1 above.

FIGURE 4: The combination of the Compound of formula (I) and ribociclib

demonstrate improved anti-proliferative and phopho-Rb suppression effects relative to single treatments in the Meljuso melanoma cell line

Shown are antiproliferative effects (FIGURE 4a, FIGURE 4b, and FIGURE 4c) and western analysis of key signalling protein (FIGURE 4d) in the NRAS mutant melanoma cell line SK- MEL-2 (NRASQ61 R). Experimental protocols and data points inf FIGURE 4a, FIGURE 4b, and FIGURE 4c are as described for FIGURE 1 above.

FIGURE 5: Anti-tumor activity of the Compound of formula (I) and ribociclib across nine patient derived NRASmut melanoma tumor xenograft models in mice.

Each bar represents the best response achieved by each treatment (plotted as the average of 3-5 mice/treatment) in an individual patient derived xenograft (PDX) model. Models for each treatment are plotted left to right in the following order: FIMEX20864, FIMEX20744, HMEX4339, HMEX5727, HMEX21 124, HMEX3486, HMEX20667, HMEX20585, and HMEX2921 .

FIGURE 6: Kaplan-Meier plot of time that tumors reached a size of 700mm³ during daily treatment of single agents the Compound of formula (I), ribociclib or

combination of both

Treatment was initiated when average tumor size of each model was around 350mm³, and all animals received continuous daily drug treatments for the duration of the study. Study was terminated when animals were treated for >/=90 days or reached a tumor size of >/=700mm³. Survival curves of the combination group was statistically significant [^*p<0.05 Log-rank (Mantel-Cox test)] when compared to each single agent or untreated controls.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a pharmaceutical combination comprising (a) a Raf inhibitor which is a Compound of formula (I), as defined herein, or a pharmaceutically acceptable salt thereof and (b) a CDK4/6 inhibitor, particularly for use in the treatment of cancer.

As used herein, the term“Raf inhibitor” refers to an adenosine triphosphate (ATP)- competitive inhibitor of B-Raf protein kinase (also referred to herein as b-RAF, BRAF or b- Raf) and C-Raf protein kinase (also referred to herein as c-RAF, CRAF or c-Raf). The Raf inhibitor preferentially inhibits both Raf monomers and Raf dimers.

Compound of formula (I) has the following structure:

(I).

For convenience, the group of the compound and its salts is collectively referred to as “Compound of formula (I)” or“Compound (I)”, meaning that reference to“Compound of formula (I)” or“Compound (I)” will refer to any of the compound or a pharmaceutically acceptable salt thereof in the alternative.

Raf inhibitor Compound of formula (I) and its pharmaceutically acceptable salts are described in WO2014/151616, which is hereby incorporated by reference in its entirety, and methods of its preparation have been described, for example, in Example 1 156 therein. The Compound of formula (I) is a potent and selective inhibitor targeting both BRAF and CRAF kinases with sub-nM inhibition concentration 50% (IC50) values in biochemical assays, while inhibiting the binding of only 2 (discoidin domain receptor tyrosine kinase 1 (DDR1 ) and platelet-derived growth factor receptor, beta polypeptide (RϋQRRb)) of 456 kinases to a similar degree. The Compound of formula (I) has demonstrated efficacy in a wide range of MAPK pathway-driven human cancer cell lines and in vivo tumor xenografts including models harboring activating lesions in the KRAS, NRAS, and BRAF oncogenes. For example, the compound of formula (I) exhibits activity in the low uM range on human pancreatic cancer cell lines that express mutations in KRAS (see WO/2018/203219 A1 , Example 1 B, Table 2).

Pharmaceutical combinations of the present invention further comprise a CDK4/6 inhibitor. The D-cyclin- CDK4/6 - RB1 axis is a major effector pathway downstream of MAPK signaling that controls the transition of cells from the G1 -to-S phase of the cell cycle.

Suitable CDK4/6 inhibitors for use in the present invention include ribociclib, or a

pharmaceutically acceptable salt thereof, and palbociclib, or a pharmaceutically acceptable salt thereof.

A CDK4/6 inhibitor useful in the pharmaceutical combinations of the invention include ribociclib or palbociclib. Ribociclib (Kisqali®) is an orally bioavailable and highly selective small molecule inhibitor with highly specific inhibitory activity against CDK4/cyclin-D1 and CDK6/cyclin-D3 enzyme complexes. A particularly useful salt of ribociclib is the succinate salt thereof.

The present invention further relates to a pharmaceutical combination comprising (a) a Raf inhibitor which is the Compound of formula (I), as defined herein, or a pharmaceutically acceptable salt thereof, and (b) a CDK4/6 inhibitor, particularly for simultaneous, separate or sequential use in the treatment of cancer.

Selected terms are defined below and throughout the application. Compounds of the present invention are described using standard nomenclature. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this invention belongs. The following general definitions shall apply in this specification, unless otherwise specified.

As used herein the term“combination of the invention” refers to the pharmaceutical combination of (a) a Raf inhibitor which is the Compound of formula (I), or a

pharmaceutically acceptable salt thereof, and (b) a CDK4/6 inhibitor, preferably ribociclib, or a pharmaceutically acceptable salt thereof. As used herein the term“combination of the invention” also refers to the co-administration or combined administration (of (a) a Raf inhibitor which is the Compound of formula (I), or a pharmaceutically acceptable salt thereof, and (b) a CDK4/6 inhibitor, preferably ribociclib, or a pharmaceutically acceptable salt thereof. The Compound of formula (I), or a pharmaceutically acceptable salt thereof, and the CDK4/6 inhibitor, preferably ribociclib, or a pharmaceutically acceptable salt thereof, may be employed in combination in accordance with the invention by administration simultaneously in a unitary pharmaceutical composition including both compounds. Alternatively, the combination may be administered separately in separate pharmaceutical compositions, each including the Raf inhibitor and a CDK4/6 inhibitor in a sequential manner wherein, for example, the Raf inhibitor or a CDK4/6 inhibitor is administered first and the other second. Such sequential administration may be close in time ( e.g simultaneously) or remote in time.

As used herein, the terms“a” and“an” and“the” and similar references in the context of describing the invention are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Where the plural form is used for compounds, salts, and the like, this is taken to mean also a single compound, salt, or the like.

The term "or" is used herein to mean, and is used interchangeably with, the term "and/or", unless context clearly indicates otherwise. "About" and "approximately" generally mean an acceptable degree of error for the quantity measured given the nature or precision of the measurements. Exemplary degrees of error are within 20 percent (%), typically, within 10%, and more typically, within 5% of a given value or range of values. When describing a dosage herein as“about” a specified amount, the actual dosage can vary by up to 10% from the stated amount: this usage of“about” recognizes that the precise amount in a given dosage form may differ slightly from an intended amount for various reasons without materially affecting the in vivo effect of the administered compound.

When describing a dosage herein as a specified amount, i.e. without the term“about”, the actual dosage can vary by up to 10% (preferably by up to 5%) from the stated amount: this usage recognizes that the precise amount in a given dosage form may differ slightly from an intended amount for various reasons without materially affecting the in vivo effect of the administered compound.

The terms“comprising” and“including” are used herein in their open-ended and non-limiting sense unless otherwise noted.

By“a combination” or“in combination with” or“co-administration”, it is not intended to imply that the therapy or the therapeutic agents must be physically mixed or administered at the same time and/or formulated for delivery together, although these methods of delivery are within the scope described herein. A therapeutic agent in these combinations can be administered concurrently with, prior to, or subsequent to, one or more other additional therapies or therapeutic agents. The therapeutic agents can be administered in any order. In general, each agent will be administered at a dose and/or on a time schedule determined for that agent. It will further be appreciated that the additional therapeutic agent utilized in this combination may be administered together in a single composition or administered separately in different compositions. In general, it is expected that additional therapeutic agents utilized in combination be utilized at levels that do not exceed the levels at which they are utilized individually. In some embodiments, the levels utilized in combination will be lower than those utilized as single-agent therapeutics.

The combinations of the invention have therapeutic or protective functions or both. For example, these molecules may be administered to a human subject, to treat and/or prevent a variety of disorders, such as cancers as described herein.

The terms“combination”,“therapeutic combination” or“pharmaceutical combination” as used herein refer to either a fixed combination in one dosage unit form, or non-fixed combination, or a kit of parts for the combined administration (co-administration) where two or more therapeutic agents may be administered together, independently at the same time or separately within time intervals, especially where these time intervals allow that the combination partners show a cooperative, e.g., synergistic, effect.

The term“combination therapy” refers to the administration of two or more therapeutic agents to treat a therapeutic condition or disorder described in the present disclosure. Such administration encompasses co-administration of these therapeutic agents in a substantially simultaneous manner, such as in a single formulation having a fixed ratio of active ingredients or in separate formulations {e.g., capsules and/or intravenous formulations) for each active ingredient. In addition, such administration and co-administration also encompass use of each type of therapeutic agent in a sequential or separate manner, either at approximately the same time or at different times. Regardless of whether the active ingredients are administered as a single formulation or in separate formulations, the drugs are administered to the same patient as part of the same course of therapy. In any case, the treatment regimen will provide beneficial effects in treating the conditions or disorders described herein.

By simultaneous therapeutic use, within the meaning of the present invention is meant an administration of at least two active ingredients by the same route and at the same time or at substantially the same time.

By separate use, within the meaning of the present invention is meant in particular an administration of at least two active ingredients at the same time or at substantially the same time by different routes.

By sequential therapeutic use is meant administration of at least two active ingredients at different times, the administration route being identical or different. More particularly by an administration method is meant according to which the whole administration of one of the active ingredients is carried out before administration of the other or others commences.

The terms“fixed combination”,“fixed dose” and“single formulation” as used herein refers to a single carrier or vehicle or dosage form formulated to deliver an amount, which is jointly therapeutically effective for the treatment of cancer, of both therapeutic agents to a patient. The single vehicle is designed to deliver an amount of each of the agents along with any pharmaceutically acceptable carriers or excipients. In some embodiments, the vehicle is a tablet, capsule, pill, or a patch. In other embodiments, the vehicle is a solution or a suspension.

The term“non-fixed combination” or“kit of parts” means that the therapeutic agents of the combination of the invention are both administered to a patient as separate entities either simultaneously, concurrently or sequentially with no specific time limits, wherein such administration provides therapeutically effective levels of the two compounds in the body of a subject in need thereof. The latter also applies to cocktail therapy, e.g., the administration of three or more active ingredients.

The term“pharmaceutically acceptable” as used herein refers to those compounds, materials, compositions and/or dosage forms, which are, within the scope of sound medical judgment, suitable for contact with the tissues of a subject, e.g., a mammal or human, without excessive toxicity, irritation, allergic response and other problems or complications commensurate with a reasonable benefit/risk ratio.

As used herein, the term“pharmaceutically acceptable excipient” or "pharmaceutically acceptable carrier" includes any and all solvents, dispersion media, coatings, surfactants, antioxidants, preservatives {e.g., antibacterial agents, antifungal agents), isotonic agents, absorption delaying agents, salts, preservatives, drugs, drug stabilizers, binders, excipients, disintegration agents, lubricants, sweetening agents, flavoring agents, dyes, and the like and combinations thereof, as would be known to those skilled in the art. Except insofar as any conventional carrier is incompatible with the active ingredient, its use in the therapeutic or pharmaceutical compositions is contemplated.

The term“pharmaceutical composition” is defined herein to refer to a mixture or solution containing at least one therapeutic agent to be administered to a subject, e.g., a mammal or human, in order or treat a particular disease or condition affecting the subject. The present pharmaceutical combinations can be formulated in suitable pharmaceutical compositions for enteral or parenteral administration, such as sugar-coated tablets, tablets, capsules or suppositories, or ampoules. If not indicated otherwise, these are prepared in a manner known per se, for example by means of various conventional mixing, comminution, direct compression, granulating, sugar-coating, dissolving, lyophilizing processes, or fabrication techniques readily apparent to those skilled in the art. It will be appreciated that the unit content of a combination partner contained in an individual dose of each dosage form need not in itself constitute an effective amount since the necessary effective amount may be reached by administration of a plurality of dosage units. The pharmaceutical composition may contain, from about 0.1 % to about 99.9%, preferably from about 1 % to about 60 %, of the therapeutic agent(s). One of ordinary skill in the art may select one or more of the aforementioned carriers with respect to the particular desired properties of the dosage form by routine experimentation and without any undue burden. The amount of each carriers used may vary within ranges conventional in the art. The following references disclose techniques and excipients used to formulate oral dosage forms: The Handbook of Pharmaceutical Excipients, 4th edition, Rowe et al., Eds., American Pharmaceuticals Association (2003); and Remington: the Science and Practice of Pharmacy, 20th edition, Gennaro, Ed.,

Lippincott Williams & Wilkins (2003). These optional additional conventional carriers may be incorporated into the oral dosage form either by incorporating the one or more conventional carriers into the initial mixture before or during granulation or by combining one or more conventional carriers with granules comprising the combination of agents or individual agents of the combination of agents in the oral dosage form. In the latter embodiment, the combined mixture may be further blended, e.g., through a V-blender, and subsequently compressed or molded into a tablet, for example a monolithic tablet, encapsulated by a capsule, or filled into a sachet.

Pharmaceutical compositions may be presented in unit dose forms containing a

predetermined amount of active ingredient per unit dose. In certain embodiments, the unit dose includes one or more vehicles such that each vehicle includes an effective amount of at least one of the therapeutic agents along with pharmaceutically acceptable carriers and excipients. In some embodiments, the unit dose is one or more tablets, capsules, pills, injections, infusions, patches, or the like, administered to the patient at the same time. As is known to those skilled in the art, the amount of active ingredient per dose will depend on the condition being treated, the route of administration and the age, weight and condition of the patient. Preferred unit dosage compositions are those containing a daily dose or sub-dose, or an appropriate fraction thereof, of an active ingredient. Furthermore, such pharmaceutical compositions may be prepared by any of the methods well known in the pharmacy art.

The pharmaceutical compositions of the invention may include a“therapeutically effective amount” or“effective amount” of a compound of the invention. The term“pharmaceutically effective amount”,“therapeutically effective amount” or“clinically effective amount” of a combination of therapeutic agents is an amount sufficient, at dosages and for periods of time necessary, to provide an observable or clinically significant improvement over the baseline of clinically observable signs and symptoms of the disorders treated with the combination. A therapeutically effective amount may vary according to factors such as the disease state, age, sex, and weight of the individual. A therapeutically effective amount is also one in which any toxic or detrimental effects of the therapeutic agents are outweighed by therapeutically beneficial effects. A "therapeutically effective dosage" preferably modulates a measurable parameter, such as tumor growth rate or disease progression in a desired manner. The ability of a compound to modulate a measurable parameter can be evaluated in an animal model system predictive of efficacy in human tumors to help establish suitable dosing levels and schedules. Alternatively, this property of a composition can be evaluated by examining the ability of the compound to modulate an undesired parameter by using in vitro assays known to the skilled practitioner.

The term“jointly therapeutically active” or“joint therapeutic effect” as used herein means that the therapeutic agents can be given jointly, separately or sequentially in such time intervals that they prefer such that the subject, especially human, to be treated, still show an (preferably synergistic) interaction (joint therapeutic effect). Whether this is the case can, inter alia, be determined by following the blood levels of the compounds, showing that both compounds are present in the blood of the human to be treated at least during certain time intervals.

As used herein the term“agent” is understood to mean a substance that produces a desired effect in a tissue, system, animal, mammal, human, or other subject. It is also to be understood that an“agent” may be a single compound or a combination or composition of two or more compounds.

The term“cancer” is preferably a cancer.

As used herein, the term“cancer” refers to a disease characterized by the undesired and uncontrolled growth of aberrant cells. Cancer cells can spread locally or through the bloodstream and lymphatic system to other parts of the body. As used herein, the term “cancer” or“tumor” includes premalignant, as well as malignant cancers and tumors. The term“cancer” is used herein to mean a broad spectrum of tumors, including all solid and hematological malignancies.

The terms “proliferative disease” or“proliferative disorder” also refer to cancer in general or to a cancer as defined herein.

An“oral dosage form” includes a unit dosage form prescribed or intended for oral administration.

As used herein, the terms“treat”,“treatment” and“treating” refer to the reduction or amelioration of the progression, severity and/or duration of a disorder, e.g., a proliferative disorder, or the amelioration of one or more symptoms, suitably of one or more discernible symptoms, of the disorder resulting from the administration of one or more therapies. In specific embodiments, the terms“treat”,“treatment” and“treating” refer to the amelioration of at least one measurable physical parameter of a proliferative disorder, such as growth of a tumor, not necessarily discernible by the patient. In other embodiments the terms“treat”, “treatment” and“treating” refer to the inhibition of the progression of a proliferative disorder, either physically by, e.g., stabilization of a discernible symptom, physiologically by, e.g., stabilization of a physical parameter, or both. In other embodiments the terms“treat”, “treatment” and“treating” refer to the reduction or stabilization of tumor size or cancerous cell count.

The terms“treat”,“treatment” and“treating” include the reduction of the incidence and severity of adverse events (AEs) and serious AEs (SAEs) including changes in laboratory values, vital signs and Electrocardiograms (ECGs) in a patient or a patient population. The terms“treat”,“treatment” and“treating” include an improvement of the overall response rate (ORR), Disease control rate (DCR), Duration of response (DOR), Progression Free Survival (PFS), e.g., as per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 , in a patient or a patient population.

Within the meaning of the present disclosure, the term“treat” also denotes to arrest, delay the onset (i.e., the period prior to clinical manifestation of a disease) and/or reduce the risk of developing or worsening a disease. The term“protect” is used herein to mean prevent, delay, or treat, or all, as appropriate, development, continuance or aggravation of a disease in a subject, e.g., a mammal or human.

The term“subject” or“patient” as used herein is intended to include animals, which are capable of suffering from or afflicted with a cancer or any disorder involving, directly or indirectly, a cancer. Examples of subjects include mammals, e.g., humans, apes, monkeys, dogs, cows, horses, pigs, sheep, goats, cats, mice, rabbits, rats, and transgenic non-human animals. In a preferred embodiment, the subject is a human, e.g., a human suffering from, at risk of suffering from, or potentially capable of suffering from a cancer, such as cancer.

The term“inhibition”,“inhibitor,” or“antagonist” includes a reduction in a certain parameter, e.g., an activity, of a given molecule or pathway. For example, inhibition of an activity of a targeted kinase (Raf or CDK4/6) by 5%, 10%, 20%, 30%, 40% or more is included by this term. Thus, inhibition may be, but need not be, 100%.

As used herein,“salts” (which, what is meant by“or salts thereof” or“or a salt thereof”), can be present alone or in mixture with free compounds of the combination of the invention, e.g., Raf inhibitor Compound with formula (I) or or CDK4/6 inhibitor, preferably ribociclib, and are preferably pharmaceutically acceptable salts. Such salts are formed, for example, as acid addition salts, preferably with organic or inorganic acids, from compounds of the combination of the invention with a basic nitrogen atom, especially the pharmaceutically acceptable salts. The term“pharmaceutically acceptable salts” refers to salts that retain the biological effectiveness and properties of the compound and which typically are not biologically or otherwise undesirable. The compound may be capable of forming acid addition salts by virtue of the presence of an amino group.

Lists of suitable salts can be found, in“Remington's Pharmaceutical Sciences”, 20th ed., Mack Publishing Company, Easton, Pa., (1985); new version: “Remington: the science and practice of pharmacy”, 22nd ed., Pharmaceutical Press, London (2012); and in“Handbook of Pharmaceutical Salts: Properties, Selection, and Use” by Stahl and Wermuth (Wiley-VCH, Weinheim, Germany, 201 1 ). For isolation or purification purposes it is also possible to use pharmaceutically unacceptable salts, for example picrates or perchlorates. For therapeutic use, only pharmaceutically acceptable salts or free compounds are employed (where applicable in the form of pharmaceutical preparations), and these are therefore preferred. In view of the close relationship between the novel compounds in free form and those in the form of their salts, including those salts that can be used as intermediates, for example in the purification or identification of the novel compounds, any reference to the free compounds is to be understood as referring also to the corresponding salts, as appropriate and expedient. The salts of compounds used in the combination of the invention are preferably pharmaceutically acceptable salts; suitable counter-ions forming pharmaceutically acceptable salts are known in the field. Unless otherwise specified, or clearly indicated by the text, reference to therapeutic agents useful in the pharmaceutical combination provided herein includes both the free base of the compounds, and all pharmaceutically acceptable salts of the

compounds.

The term“synergistic effect” as used herein, refers to action of two agents such as, for example, Raf inhibitor Compound with formula (I), or a pharmaceutically acceptable salt thereof, and a CDK4/6 inhibitor, preferably ribociclib, or a pharmaceutically acceptable salt thereof, to produce an effect, for example, slowing the symptomatic progression of cancer or symptoms thereof, which is greater than the simple addition of the effects of each drug administered by themselves.

In one embodiment, the combination of the invention comprises (a) a Raf inhibitor which is the Compound of formula (I)

or a pharmaceutically acceptable salt thereof and (b) a CDK4/6 inhibitor.

In one embodiment, the combination of the invention comprises (a) a Raf inhibitor

Compound of formula (I)

(I),

or a pharmaceutically acceptable salt thereof, and (b) a CDK4/6 inhibitor selected from ribociclib and palbociclib, and pharmaceutically acceptable salts thereof. The CDK4/6 inhibitor is preferably ribociclib, or a pharmaceutically acceptable salt thereof.

Combinations of the invention demonstrated increased depth and durability of tumor response compared to either single-agent therapy in cell lines and human xenograft models, (see Examples), and may therefore be effective for the treatment of a cancer. Accordingly, the invention provides compositions and methods using a Raf inhibitor which is the

Compound of formula (I), or a pharmaceutically acceptable salt thereof, in combination with a CDK4/6 inhibitor, and in particular with ribociclib, or a pharmaceutically acceptable salt thereof for treating solid tumors, particularly tumors that harbor one or more MAPK pathway alterations, e.g. NRAS-mutant cancers and KRAS-mutant cancers.

Preferably, these therapeutic agents are administered at therapeutically effective dosages which, when combined, provide a beneficial effect. The present invention particularly pertains to a combination of the invention useful for separate, simultaneous or sequential administration to a subject in need thereof for treating a cancer. Alternatively stated, the present invention particularly pertains to a combination of the invention for use in the treatment of a cancer.

The nature of cancer is multifactorial. Under certain circumstances, therapeutic agents with different mechanisms of action may be combined. However, just considering any

combination of therapeutic agents having different modes of action does not necessarily lead to combinations with advantageous effects and does not necessarily translate into clinical benefit for patients suffering from certain cancers.

In the present invention, the administration of the combination of the invention is expected to result in a more beneficial effect, e.g., a synergistic or improved anti-proliferative effect, e.g., with regard to the delay of progression or inhibiting the cancer or its symptoms, and may also provide further beneficial effects such as any one or more of the following: fewer side- effects such as skin-related toxicity (e.g. rash) and gastro-intestitinal-toxicity (e.g. diarrhea), improved tolerability, higher quality of life and decreased morbidity, as compared to any therapy in the prior art or to monotherapy with any one of the combination partners.

The therapeutic agents of the combination of the invention may be separately,

simultaneously or sequentially administered to a subject in need thereof. Preferably, these therapeutic agents are administered at therapeutically effective dosages which, when combined, provide a beneficial effect. Thus, in one embodiment of the present invention, the combination of the invention is for use in the treatment of cancer, particularly a cancer as described herein.

The term“cancer” is used herein to mean a broad spectrum of tumors, including all solid and hematological malignancies. The cancer may be at an early, intermediate or late stage. The cancer may be locally advanced or metastatic.

The cancer to be treated by the combination therapy described herein may have progressed following standard of care or for whom no effective standard therapy exists.

In one embodiment, the cancer is melanoma.

The combination of the invention is particularly useful for the treatment of a cancer such as a cancer that harbors one or more Mitogen-activated protein kinase (MAPK) pathway alterations, such as an NRAS-mutant tumor, and in particular, a tumor expressing at least one gain-of-function mutation of Ras, as described herein, and/or at least one gain-of- function mutation of Raf, as described herein.

Included are NRAS mutant cancers or tumors. NRAS mutations of interest may be selected from G12C, G12R, G12D, G12V, G12S, G12A, G13R, G13D, G13C, G13A, G13, G13S, G13V, Q61 R, Q61 L, Q61 K, Q61 H, Q61 P and Q61 E. The term“NRAS-mutant” tumor or cancer includes any tumor that exhibits a mutated NRAS protein, in particular gain of function NRAS-mutation; especially any G13R, Q61 K, Q61 L, Q61 R, NRAS-mutant tumor. Thus NRAS-mutant melanoma includes melanoma having at least one NRAS mutation corresponding to Q61 K, Q61 L or Q61 R. The cancer may be NRAS QG13R-mutant melanoma. Included are also KRAS mutant cancers or tumors. KRAS mutations of interest may be selected from G12C, G12R, G12D, G12V, G12S, G12A, G13R, G13D, G13C, G13A, G13, G13S, G13V, Q61 R, Q61 L, Q61 K, Q61 H, Q61 P and Q61 E. The term“KRAS-mutant” tumor or cancer includes any tumor that exhibits a mutated KRAS protein. The cancer may be at an early, intermediate or late stage. The cancer may be locally advanced or metastatic.

In another embodiment, the cancer is resistant or refractory to standard of care. In another embodiment, the cancer is resistant or refractory to standard of care with dacarzabine.

In another embodiment, the cancer is resistant or refractory to treatment with a MEK inhibitor.

In another embodiment, thecancer is resistant or refractory to treatment with immunotherapy treatment including therapy with one or more immune checkpoint inhibitors.

In another embodiment, the cancer is resistant or refractory to treatment with a cytotoxic agent such as a nitrosurea and/or mitomycin C.

In one embodiment, the cancer is characterized by at least one mutation selected from the group comprising NRAS proteins.

In one embodiment, the cancer is characterized by an NRAS mutation.

In one embodiment, the combination of the invention relates to a method for treating a cancer, particularly a melanoma.

The combination of the invention may be especially useful in treating NRAS-mutant melanoma.

In one embodiment, the cancer is characterized by at least one mutation selected from the group comprising KRAS proteins.

In one embodiment, the cancer is characterized by an KRAS mutation.

In one embodiment, the combination of the invention relates to a method for treating a cancer, particularly a pancreatic cancer.

The combination of the invention may be especially useful in treating KRAS-mutant PDAC.

In one embodiment, provided herein is a method for treating cancer in a subject in need thereof comprising administering a therapeutically effective amount of a pharmaceutical combination of the invention comprising (a) a Raf inhibitor which is the Compound of formula (I), as defined herein, or a pharmaceutically acceptable salt thereof, and (b) a CDK4/6 inhibitor. In a preferred embodiment, the CDK4/6 inhibitor is ribociclib, or a pharmaceutically acceptable salt thereof. In an embodiment, provided herein is a method for treating cancer in a subject in need thereof comprising administering simultaneously, separately or sequentially to a subject in need thereof a combination of the invention in a quantity which is jointly therapeutically effective against said cancer wherein the combination of the invention comprises (a) a Raf inhibitor which is the Compound of formula (I), as defined herein, or a pharmaceutically acceptable salt thereof and (b) a CDK4/6 inhibitor. In a preferred embodiment, the CDK4/6 inhibitor is ribociclib, or a pharmaceutically acceptable salt thereof.

In a further embodiment, the present invention is particularly related to a method of treating a cancer harboring one or more Mitogen-activated protein kinase (MAPK) pathway alterations. In one embodiment, the present invention is related to a method of treating a cancer, which is characterized by at least one mutation in NRAS. In another embodiment, the present invention is related to a method of treating a cancer, which is characterized by at least one mutation in KRAS. In one embodiment, the present invention relates to the use of the combination of the invention for the preparation of a medicament for the treatment of cancer, particularly a cancer as described herein. In one embodiment, the combination of the invention is for use in the preparation of a medicament for the treatment of cancer.

In a further embodiment, the present invention relates to the use of the combination of the invention for the preparation of a medicament for the treatment of a cancer characterized by gain-of-function mutation in the MAPK pathway.

In an embodiment, the combination or composition, or both, provided herein display a synergistic effect.

Accordingly, in one aspect, the invention may provide a method of enhancing the efficacy of an anticancer compound by using it in combination with another anticancer compound, particularly a method using a Raf inhibitor which is the Compound of formula (I), as defined herein, or a pharmaceutically acceptable salt thereof, together with a CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt, thereof to provide enhanced efficacy which is not achievable by administering similar doses of either the Compound of formula (I), or a pharmaceutically acceptable salt thereof, or the CDK4/6 inhibitor as a single agent (monotherapy).

A further benefit provided by the invention may be that lower doses of the therapeutic agents of the combination of the invention can be used, for example, such that the dosages may not only often be smaller, but also may be applied less frequently, or can be used in order to diminish the incidence of side-effects observed with one of the combination partners alone. In some embodiments, the Compound of formula (I), as defined herein, or a

pharmaceutically acceptable salt thereof, and/or the CDK4/6 inhibitor, preferably ribociclib, or a pharmaceutically acceptable salt thereof, may be administered at a therapeutic or lower- than therapeutic dose relative to a single-agent dose level. In certain embodiments, the concentration or dosage of the one therapeutic agent that is required to achieve inhibition, e.g., growth inhibition or tumor shrinkage is lower when the other therapeutic agent is used or administered in combination with the first therapeutic agent than when each therapeutic agent is administered individually. In certain embodiments, in a combination therapy, the concentration or dosage of one therapeutic agent that is required to achieve inhibition, e.g., growth inhibition, is lower than the therapeutic dose as a monotherapy, e.g., 10-20%, 20- 30%, 30-40%, 40-50%, 50-60%, 60-70%, 70-80%, or 80-90% lower.

In determining a synergistic interaction between one or more components, the optimum range for the effect and absolute dose ranges of each component for the effect may be definitively measured by administration of the components over different w/w ratio ranges and doses to patients in need of treatment. For humans, the complexity and cost of carrying out clinical studies on patients may render the use of this form of testing as a primary model for synergy impractical. However, the observation of synergy in certain experiments can be predictive of the effect in other species, and animal models exist may be used to further quantify a synergistic effect. The observation of synergy in one species can be predictive of the effect in other species and using animal models, as described herein, a synergistic effect can be measured and the results of such studies can also be used to predict effective dose ratio ranges and the absolute doses and plasma concentrations required in other species by the application of pharmacokinetic/pharmacodynamic (PK/PD) methods. Established correlations between tumor models and effects seen in man suggest that synergy in animals may be demonstrated, for example, by xenograft models or in appropriate cell lines. It can be shown by established test models that a combination of the invention results in the beneficial effects described herein. The person skilled in the art is fully enabled to select a relevant test model to prove such beneficial effects. The pharmacological activity of the combination of the invention may, for example, be demonstrated in a clinical study or in an in vivo or in vitro test procedure as essentially described herein.

Administration of the combination, (in other words, administration of the one therapeutic agent with the other combination partner i.e.“co-administration”) includes administration of the combination in a single formulation or unit dosage form, administration of the individual agents of the combination concurrently but separately, or administration of the individual agents of the combination sequentially by any suitable route. The individual combination partners of the combination of the invention may be administered separately at different times during the course of therapy, or sequentially in any order or concurrently in divided or single combination forms, e.g., simultaneously or in jointly therapeutically effective amounts, preferably in synergistically effective amounts, e.g., in daily or intermittent (i.e., not daily) dosages corresponding to the amounts described herein.

The Compound of formula (I), or a pharmaceutically acceptable salt thereof, for use in the methods, treatments, combinations and compositions disclosed herein is a potent inhibitor of BRAF and CRAF. In some embodiments, the Compound of formula (I), or a

pharmaceutically acceptable salt thereof, is administered orally. In one embodiment, the Compound of formula (I), or a pharmaceutically acceptable salt thereof, is administered at a total daily dose of about 200-1200 mg, about 300-1000 mg, about 400-800 mg, or about 500-600 mg (e.g., once per day). The Compound of formula (I), or a pharmaceutically acceptable salt thereof, can be administered at a total daily dose of about 200 mg, about 250 mg, about 300 mg, about 350 mg, about 400 mg, about 450 mg, about 500 mg about 550 mg, about 600 mg, about 650 mg, about 700 mg, about 750 mg, about 800 mg, about 850 mg, about 900 mg, about 950 mg, about 1000 mg, about 1050 mg, about 1 100 mg, about 1 150 mg or about 1200 mg. In a preferred embodiment, the Compound of formula (I), or a pharmaceutically acceptable salt thereof, may be administered at a total daily dose selected from about 200 mg, 400 mg, 600 mg, 800 mg and 1200 mg.

The total dose of the Compound of formula (I), or a pharmaceutically acceptable salt thereof, may be administered once daily, or may be divided into two and each dose of the Compound of formula (I) administered twice daily, with the actual dosage and timing of administration determined by criteria such as the patient’s age, weight, and gender; the extent and severity of the cancer to be treated; and the judgment of a treating physician. Preferably, the total dose of the Compound of formula (I) is administered once daily. In another preferred embodiment, the total dose of the Compound of formula (I) is administered twice daily.

The CDK4/6 inhibitor as part of the combination according to the present invention is administered to a subject in need thereof in a therapeutically effective amount.

In a preferred embodiment, the total daily dose of CDK4/6 inhibitor ribociclib, or a

pharmaceutically acceptable salt thereof, administered daily as part of the combination according to the present invention in a subject in need thereof will be an amount selected from about 100 mg to about 600 mg per day; suitably, the amount will be selected from about 200 mg to about 400 mg per day. In a preferred embodiment, ribociclib, or a pharmaceutically acceptable salt thereof is administered at daily dose selected from about 100, about 200 mg, about 400 mg and about 600 mg. Alternatively, the total dose may be divided in two doses, which are administered twice daily.

In particular, the following daily doses may be envisaged:

Daily dose of the Daily dose of ribociclib

Compound of formula (I)

200 mg 100 mg, 200 mg, 400 mg, 600 mg, or 900 mg

400 mg 100 mg, 200 mg, 400 mg, 600 mg, or 900 mg

600 mg 100 mg, 200 mg, 400 mg, 600 mg, or 900 mg

800 mg 100 mg, 200 mg, 400 mg, 600 mg, or 900 mg

1200 mg 100 mg, 200 mg, 400 mg, 600 mg, or 900 mg

1600 mg 100 mg, 200 mg, 400 mg, 600 mg, or 900 mg

Where doses or dosages are mentioned herein, the amount referred to refers to the amount of the therapeutic agent. For example, when a 200 mg dose of ribociclib is administered, and ribociclib is administered in a tablet containing ribociclib succinate, the tablet will contain ribociclib succinate equivalent to 200 mg ribociclib.

In some embodiments, ribociclib, or a pharmaceutically acceptable salt thereof is administered orally. In one embodiment, ribociclib is prepared for administration via oral delivery, and may be used in the salt form, e.g. the succinate salt form. In some

embodiments, the compound is prepared in tablet form for oral administration. The tablets can be produced in a variety of dosages for flexible administration.

The dose of ribociclib, or a pharmaceutically acceptable salt thereof may be administered once daily, or twice daily, or three times daily, or four times daily. The total daily dose of ribociclib, or a pharmaceutically acceptable salt thereof, may be administered once or twice a day.

For example, as part of the combination therapy, the Compound of formula (I), or a pharmaceutically acceptable salt thereof, may be administered at a total daily dose of about 200 mg, about 400 mg, about 600 mg, about 800 mg or about 1200 mg and ribociclib, e.g. in the succinate salt form, may be administered in a total daily dose selected from about 100 mg, about 200 mg, about 400 mg and about 600 mg. The daily dose of the Compound of formula (1 ) may be administered once or twice per day. Flence, a dose of about 200 mg of the Compound of formula (I) may be administered twice per day and (total daily dose about 400 mg) and a dose of about 100 mg or about 200 mg of ribociclib may be administered once per day. Alternatively, a dose of about 200 mg of the Compound of formula (I) may be administered twice per day and (total daily dose about 400 mg) and a dose of about 100 mg or about 200 mg of ribociclib may be administered twice per day.

Alternatively, the Compound of formula (I) may be administered 600 mg twice a day (b.i.d or BID) and ribociclib administered at 600 mg once a day. The Compound of formula (I) may be also be administered 400 mg twice a day (BID) and ribociclib administered at 200 mg once a day.

The Compound of formula (I) is preferably administered continuously, i.e. without a drug holiday period.

The CDK4/6 inhibitor may be administered either continuously i.e. without a break during the treatment period, or with a drug holiday period.

For example, the CDK4/6 inhibitor, e.g. ribociclib or a pharmaceutically acceptable salt thereof, may be administered 3 weeks on and 1 week off, or 2 weeks on and 2 weeks off; preferably 3 weeks on and 1 week off. In particular, the following regimens may be used according to the present invention

b.i.d. or BID: twice a day qd or QD: once daily

For example, the Compound of formula (I) may be given without a drug holiday period once or twice a day and the CDK4/6 inhibitor (e.g. ribociclib, or a pharmaceutically acceptable salt thereof) may be administered three weeks on and one week off.

In the drug regimens envisaged, the total daily doses of the Compound of formula (I) and of the CDK4/6 inhibitor are as described above and throughout the description. For example, a dose of 400 mg or 600 mg of the Compound of formula (I) may be given once or twice a day, preferably twice a day, and a dose of 200 mg of ribociclib may be given once a day, three weeks on and one week off.

For example, a dose of 600 mg of the Compound of formula (I) may be given once or twice a day, preferably twice a day, and a dose of 600 mg of ribociclib may be given once a day, three weeks on and one week off.

The Compound of formula (I), or a pharmaceutically acceptable salt thereof, and a CDK4/6 inhibitor, preferably ribociclib, or a pharmaceutically acceptable salt thereof can be used together according to methods disclosed herein. The two compounds can be administered together or separately, depending on the intended dosage amount and frequency of administration, since it is contemplated that the treatments of the invention may be continued for 2 days, 3 days, 4 days, 5 days, 6 days, 1 week, 2 weeks, 3 weeks, 4 weeks, or more than 4 weeks as deemed appropriate to the treating physician, and further as guided using methods described herein to determine a suitable dosage and administration frequency. Frequency of dosage may vary depending on the compound used and the particular condition to be treated. In general, the use of the minimum dosage that is sufficient to provide effective therapy is preferred and may be determined by criteria such as the patient’s age, weight, and gender; the extent and severity of the cancer to be treated; and the judgment of a treating physician. Patients may generally be monitored for therapeutic effectiveness using assays suitable for the condition being treated, which will be familiar to those of ordinary skill in the art.

The optimum ratios, individual and combined dosages, and concentrations of the

combination partners of the combination of the invention, (i.e., Compound of formula (I), or a pharmaceutically acceptable salt thereof, and a CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof, that yield efficacy without toxicity are based on the kinetics of the therapeutic agents’ availability to target sites and a variety of factors, including, but not limited to, the degree of advancement of the disease; the age, body weight, general health, gender and diet of the individual; the time and route of administration; and other medications the individual is taking. Optimal dosages may be established using routine testing and procedures that are well known in the art. For example, a single bolus may be administered, several divided doses may be administered over time or the dose may be proportionally reduced or increased as indicated by the exigencies of the therapeutic situation. The therapeutic agents of the combination of the invention may be administered by any appropriate route. It will be appreciated that the preferred route may vary with, for example, the condition of the recipient of the combination and the location of the cancer to be treated.

It will also be appreciated that each of the therapeutic agents may be administered by the same or different routes and that the therapeutic agents, e.g., the Compound of formula (I), or a pharmaceutically acceptable salt thereof, and the CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof, may be compounded together in a

pharmaceutical composition.

The Compound of formula (I), or a pharmaceutically acceptable salt thereof, and the CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof, can be used together as disclosed herein. The two therapeutic agents of the combination of the invention can be administered together (simultaneously), sequentially or separately.

Furthermore, it does not matter if the compounds are administered in the same dosage form, e.g., one compound may be administered topically and the other compound may be administered orally. Suitably, both therapeutic agents are administered orally. The compounds can be can be administered in the same or different dosage form.

Thus in one embodiment, one or more doses of the Compound of formula (I), or a pharmaceutically acceptable salt thereof, are administered simultaneously, sequentially or separately with one or more doses of a CDK4/6 inhibitor, suitably ribociclib, or a

pharmaceutically acceptable salt thereof.

In one embodiment, multiple doses of the Compound of formula (I), or a pharmaceutically acceptable salt thereof, are administered simultaneously, sequentially or separately with multiple doses of a CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof.

In one embodiment, multiple doses of the Compound of formula (I), or a pharmaceutically acceptable salt thereof, are administered simultaneously, sequentially or separately with one dose of a CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof.

In one embodiment, one dose of the Compound of formula (I), or a pharmaceutically acceptable salt thereof, is administered simultaneously, sequentially or separately with multiple doses of a CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof. In one embodiment, one dose of the Compound of formula (I), or a pharmaceutically acceptable salt thereof, is administered simultaneously, sequentially or separately with one dose of a CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof.

In all the above embodiments, the Compound of formula (I), or a pharmaceutically acceptable salt thereof, may be administered first or the CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof may be administered first.

In one embodiment, provided herein is a pharmaceutical composition comprising (a) the Compound of formula (I), or a pharmaceutically acceptable salt thereof, and (b) a CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof for use in the methods of the invention. In an embodiment, the pharmaceutical composition further comprises one or more pharmaceutically acceptable diluents, excipients or carriers. The carrier(s), diluent(s) or excipient(s) must be acceptable in the sense of being compatible with the other ingredients of the formulation, capable of pharmaceutical formulation, and not deleterious to the recipient thereof. Such elements of the pharmaceutical compositions utilized may be presented in separate pharmaceutical combinations or formulated together in one pharmaceutical composition. The combinations disclosed herein can be administered together in a single composition or administered separately in two or more different compositions, e.g., compositions or dosage forms as described and the components may be administered as the same formulation, or as separate formulations, alone, e.g., as indicated above, or in combination with one or more pharmaceutically acceptable carriers by any suitable route.

Dosage unit forms as used herein refer to physically discrete units suited as unitary dosages for the subjects to be treated; each unit contains a predetermined quantity of active compound (e.g., the Compound of formula (I), or a pharmaceutically acceptable salt thereof, or the CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof, calculated to produce the desired therapeutic effect in association with the required pharmaceutical carrier. The unit dosage form may also be a fixed combination.

The effective dosage of each of the combination partners may require more frequent administration of one of the therapeutic agent as compared to the other therapeutic agent in the combination. Therefore, to permit appropriate dosing, packaged pharmaceutical products may contain one or more dosage forms that contain the combination of compounds, and one or more dosage forms that contain one of the therapeutic agents of the combination of the invention, but not the other therapeutic agent of the combination of the invention. When the combination partners, which are employed in the combination of the invention, are applied in the form as marketed as single drug, their dosage and mode of administration can be in accordance with the information provided on the package insert of the respective marketed drug, if not mentioned otherwise.

Therefore, to permit appropriate dosing, packaged pharmaceutical products can contain one or more dosage forms that contain the combination of agents, and one or more dosage forms that contain one of the therapeutic agents of the combination, but not the other therapeutic agent of the combination.

Also within the scope of the invention is a combination kit comprising, as therapeutic agents, the combination of the invention for simultaneous, separate or sequential administration as described herein, together with one or more other elements: instructions for use; other reagents for use with the combination of the invention; devices or other materials for preparing the compound for administration, such as a mixing container; pharmaceutically acceptable carriers; and devices or other materials for administration to a subject, such as a syringe.

By the term“combination kit” or“kit of parts” as used herein is meant the pharmaceutical composition or compositions that are used according to the invention. When both

compounds are administered simultaneously, the combination kit can contain the Compound of formula (I), or a pharmaceutically acceptable salt thereof, and the CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof and the CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof in a single pharmaceutical composition, such as a tablet, or in separate pharmaceutical compositions. When the Compound of formula (I), or a pharmaceutically acceptable salt thereof, and the CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof and the CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof are not

administered simultaneously, the combination kit will contain the Compound of formula (I), or a pharmaceutically acceptable salt thereof, and the CDK4/6 inhibitor, suitably ribociclib, or a pharmaceutically acceptable salt thereof in separate pharmaceutical compositions either in a single package or in separate pharmaceutical compositions in separate packages.

In one embodiment of the invention the kit of parts comprising the following components: (a) a Raf inhibitor compound selected from the group consisting of (i) the Compound of formula (I), or a pharmaceutically acceptable salt thereof, in association with pharmaceutically acceptable excipients, diluents and/or carriers, and (b) a CDK4/6 inhibitor, preferably ribociclib, or a pharmaceutically acceptable salt thereof in association with a pharmaceutically acceptable excipients, diluents or carrier, wherein the components are provided in a form which is suitable for sequential, separate and/or simultaneous

administration. The combination kit can also be provided with instructions, such as dosage and administration instructions. Such dosage and administration instructions can be of the kinds that are provided to a doctor, for example by a drug product label, or they can be of the kinds that are provided by a doctor, such as instructions to a patient.

Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.

The following Examples illustrate the invention described above; they are not, however, intended to limit the scope of the invention in any way. The beneficial effects of the pharmaceutical combination of the present invention can also be determined by other test models known as such to the person skilled in the pertinent art.

EXAMPLES

EXAMPLE 1 : Enhanced combination effects of RAF inhibition with CDK4/CDK6 inhibition in NRAS mutant melanoma cell lines

Method

The Compound of formula (I) (NVP-LXH254) and ribociclib (NVP-ribociclib) were

synthesized and compound stocks of ribociclib were prepared in DMSO at a final concentration of 10 mM. For combination plots, working stocks were serially diluted in the appropriate cell culture medium in 3-fold increments (2-fold increments for ribociclib) to achieve final assay concentrations ranging from 10 mM to 1.5 nM for NVP-LXH254 and 10 mM to 39 nM for NVP-ribociclib (in the succinate salt form).

SK-MEL-2 cells were purchased from American Type Culture Collection (ATCC), MEL-JUSO cells were purchased from Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH (DSMZ), MM415 cells were purchased from Cell Bank Australia, and IPC-298 and SK-MEL-30 cells were acquired from GNF. IPC-298, MEL-JUSO, MM415, and SK-MEL-30 cells were cultured in RPMI medium (ATCC) and the SK-MEL-2 cells were cultured in EMEM medium (ATCC) both supplemented with 10% fetal bovine serum (Gibco) and incubated at 37°C/5% C02. For combination activity, cells were seeded in 80 pi of medium in 96-well plates (Corning #3904) at 5,000 cells per well and incubated overnight prior to compound addition. Compound stock (1 Ox) was freshly prepared in the appropriate culture medium, and manually added to the plates by electronic multichannel pipette to create a full 10x10 combination matrix grid. In a minimum of three replicate wells, the number & viability of cells at the time of compound addition, as well as quantification of combination effects after 72 hours, were assessed by the fluorescence-based DNA-binding proliferation assay,

CyQUANT® Direct (Thermo #C3501 1 ) according to the manufacturer’s protocol.

Combination data analysis was performed using the internal Novartis software, Combination Analysis Module. The application utilized the Loewe dose additivity model to calculate a weighted synergy score across each dose matrix that adjusts for dose sampling and coverage, and weights to favor combination effects at high inhibition levels (Lehar et al., 2009).

Cells were plated in 6-well dishes (#3506, Corning, NY) at a density of 0.5x106 cells per well. One day after plating, lines were treated with single agent ribociclib at 200, 400, and 800 nM and with the combination of the Compound of formula (I) (300 nM) for 48 hours.

Cells were harvested in RIPA lysis buffer (#89900, Thermo Fisher, Waltham, MA) containing protease inhibitors (#87785, Thermo Fisher, Waltham, MA) and phosphatase inhibitors (#78420, Thermo Fisher, Waltham, MA). Proteins were separated on a 4-12% Bis-Tris NuPAGE SDS gel (#WG1403Bx10, Life Technologies, Carlsbad, CA) and transferred to nitrocellulose using the Trans-Blot Turbo System (Bio-Rad, Hercules, CA). Proteins were detected with 1 :1000 dilutions of antibodies recognizing pRB (#8516, Cell Signaling

Technology, Beverly, MA ), pCDK4/61/2 (#9154, Cell Signaling Technology, Beverly, MA), pERK1/2 (#4730, Cell Signaling Technology, Beverly, MA), and pRSK (#9348, Cell Signaling Technology, Beverly, MA) and 1 :5000 dilution of an antibody recognizing b-actin (#AM4302, Life Technologies, Carlsbad, CA). Protein levels were detected using anti-mouse-HRP or anti-rabbit-HRP secondary antibodies and developed with SuperSignal West Femto

(#34096, Thermo Scientific, Waltham, MA) or Dura Chemiluminescent substrate (#34076, Thermo Scientific, Waltham, MA) on a GE Image Quant LAS 4000 imaging system (GE Healthcare, Woburn, MA).

Results

The combination of the Compound of formula (I) and ribociclib demonstrated improved anti proliferative and phopho-Rb suppression effects relative to single treatments in the SK-MEL- 30 melanoma cell line (FIGURE 1 ). The SK-MEL-30 melanoma cell line harbors co-incident mutations in NR AS (Q61 K) and BRAF (D287H).

The combination of the Compound of formula (I) and ribociclib demonstrated improved anti proliferative and phopho-Rb suppression effects relative to single treatments in the IPC-298 melanoma cell line (FIGURE 2). The IPC-298 melanoma cell line harbors a NRAS mutation (NRASQ61 L). The combination of the Compound of formula (I) and ribociclib demonstrated improved anti proliferative and phopho-Rb suppression effects relative to single treatments in the Meljuso melanoma cell line (FIGURE 3). The Meljuso melanoma cell line harbors a NRAS mutation (NRASQ61 L).

The combination of the Compound of formula (I) and ribociclib demonstrated improved anti proliferative and phopho-Rb suppression effects relative to single treatments in the Meljuso melanoma cell line (FIGURE 4).

EXAMPLE 2: Combination efficacy of the Compound of formula (I) and ribociclib in NRAS mutant melanoma patient derived xenografts

The effect of selective dual RAF and CDK4/6 inhibition in vivo was investigated by combining the Compound of formula (I) and ribociclib in nine NRAS mutant patient derived melanoma xenografts. Methods

Animals and maintenance conditions: Outbred athymic (nu/nu) female mice (Athymic Nude- nu”) (Charles River, Indianapolis) were allowed to acclimate in the Novartis NIBR animal facility with access to food and water ad libitum for minimum of 3 days prior to manipulation (Table 1 ).

Table 1 Animal Characteristics

Statement on animal welfare: Animals were handled in accordance with Novartis NIBR ACUC regulations and guidelines.

Test compound and formulations: the Compound of formula (I) (free base form) was dosed p.o. (orally) in MEPC4 vehicle (45% Cremophor RH40 + 27% PEG400 + 18% Corn Oil Glycerides + 10% ethanol). The Compound of formula (I) was formulated at 5 mg/mL.

Ribociclib succinate salt was dosed p.o. (orally) in a vehicle of 0.5% methyl cellulose;

ribociclib was formulated at 7.5 mg/mL.

Patient derived xenograft (PDX) model development in nude mice

HMEX5727, HMEX3486, HMEX20667, HMEX2921 , HMEX20864, HMEX20585,

HMEX4339, HMEX20744, and HMEX21 124 patient-derived tumor xenografts (PDX) were propagated by serial passage of tumor slurry in nude mice. Briefly, fragments of fresh tumor from a previous passage were homogenized using gentle MACS Dissociator (MACS

(Miltenyi Biotec, #120-005-331 ), passed through a tissue grinder (Chemglass lifeSciences # CLS-5020-085), diluted in PBS, and mixed with an equal volume of Matrigel™ Matrix (Corning #354234). Then 200 ul of tumor slurry was implanted subcutaneously into the right flank of female nude mice. Tumor volume was determined by measurement with calipers and calculated using a formula, where tumor volume (V ) (mm³) = (I x w2)/2, where I is the longest axis of the tumor and w is perpendicular to I. Mice were monitored for tumor growth, body weight and body condition twice/week.

Efficacy Study Design in PDX models

The efficacy study design for all models is described in Table 2. Test agents were dosed at dose volume of 10 mL/kg which was adjusted according to body weight. Tumor dimensions and body weights were collected at the time of randomization and twice weekly thereafter for the study duration. Mice were randomized into treatment groups (n=3-5/group) when the average tumor volume was approximately 350 mm³, and treatments were carried out until tumor outgrowth (tumor volume >/=700mm³) or approximately 90 days. Percent change in tumor volume was determined for all models by comparing tumor volume change at time t to its baseline. The best response was the minimum value of percent tumor volume change for t ³ 10 days. At the time the untreated control mice were sacrificed, 2 mice from each group were also sacrificed, and the tumors collected for future pharmacodynamics (PD) analysis. The efficacy was carried out with 3 mice/group beyond this point.

Table 2 Treatment groups for efficacy studies

p.o.: per os (oral gavage)

qd: once a day

bid: twice a day

Data Analysis

Body Weight: The percent change in body weight was calculated as ( BW_CUrrent -

BW ini_tial)/ ( BW ini_tial) x 100%. Data was presented as mean percent body weight change from the day of treatment initiation ± SEM.

Tumor volume: Percent change in tumor volume was determined by comparing tumor volume change at time t to its baseline using the following formula: % tumor volume change = AV = 100% x ((V_t- V i_nitial) / V i_nitial) - The best response was the minimum value of AV for t ³ 10 days.

Where:

AV =change in tumor volume

V = tumor volume of the drug-treated (or untreated) group on a given day of the study;

Vi_nitiai=tumor volume of the drug treated (or untreated) group on initial day of dosing. Best response >/= -30% was considered tumor regression.

Kaplan-Meier survival plot was generated using GraphPad Prism software for individual mice that reached an end point of tumor size >/=700mm³ Statistical analysis for significance between groups was performed using Log-rank (Mantel-Cox) test. p<0.05 was considered significant. Results: Combination efficacy of the Compound of formula (I) and ribociclib in patient derived NRAS mutant melanoma xenograft models in nude mice

The antitumor efficacy of the Compound of formula (I) when combined with ribociclib was determined using nine NRAS mutant patient derived melanoma xenograft models in nude mice: HMEX5727 (NRASQ61 K), HMEX3486 (NRASQ61 K), HMEX20667 (NRASQ61 R), HMEX2921 (NRASQ61 R), HMEX20585 (NRASQ61 R), HMEX20864 (NRASQ61 R),

HMEX21 124 (NRASQ61 H), HMEX20744 (NRASQ61 K), and HMEX4339 (NRASQ61 R).

Mice were treated for approximately 90-100 days or until tumor size in each group reached >/=700mm³. Percent change in tumor volume (best response), percent change in body weight, and survival are reported in Table 3, FIGURE 5 and FIGURE 6.

The combined activity of the Compound of formula (l)+ribociclib dosed at 50 mg/kg bid and the Compound of formula (I)) + 75 mg/kg qd (ribociclib) led to tumor regression in 44% of the models tested. In comparison, neither single agent the Compound of formula (I) dosed at 50 mg/kg bid nor single agent ribociclib dosed at 75 mg/kg qd achieved tumor regression in any of the models tested (Table 3 and FIGURE 5). In addition, the combination of the Compound of formula (l)+ribociclib led to significantly increased median survival, compared to each single agents or untreated controls (FIGURE 6).

Both single agents and combination treatments were very well tolerated as judged by lack of body weight loss across models. One mouse treated with the Compound of formula (I) was sacrificed at an earlier time point due to body weight loss.

Table 3: Anti-tumor efficacy and tolerability of the Compound of formula (I) and ribociclib in nine patient derived NRAS mutant melanoma tumor xenograft models in mice

Indicates last day of treatment (tumor size >/=700mm³)

#group run in a separate experiment

Conclusion and Discussion The in vivo activity of the Compound of formula (l)+ribociclib combination in NRAS mutant melanoma was profiled in a panel of nine NRAS mutant patient derived melanoma xenografts. The combined activity of the Compound of formula (l)+ribociclib dosed at 50 mg/kg bid (the Compound of formula (I)) + 75 mg/kg qd (ribociclib) led to tumor regression in 44% of the models tested. In comparison, neither single agent the Compound of formula (I) dosed at 50 mg/kg bid nor single agent ribociclib dosed at 75 mg/kg qd achieved tumor regression in any of the models tested. In addition, the combination of the Compound of formula (l)+ribociclib was well tolerated and led to significantly increased median percent survival, compared to each single agent or untreated controls. A strong synergy of the CDK4/6 inhibitor ribociclib with the Compound of formula (I) has been observed in NRAS mutant patient derived melanoma xenografts, leading to significant tumor regression and increased median percent survival in preclinical models. Collectively, these data indicate that the combination of the Compound of formula (l)+ribociclib may achieve greater and more durable responses in NRAS mutant melanoma patients. EXAMPLE 3: A Phase lb, open-label, multicenter study of the Compound of formula (I) in combination with ribociclib in patients with NRAS mutant melanoma

The purpose of the study is to characterize the safety and the tolerability of the dual combination the Compound of formula (I) and ribociclib in patients with NRAS mutant melanoma and identify a recommended dose.

Primary endpoints are

(1 ) safety: incidence and severity of adverse events (AEs) and serious AEs (SAEs) including changes in laboratory values, vital signs and Electrocardiograms (ECGs), incidence and nature of dose limiting toxicities (DLTs) during the first cycle (dose escalation only),

(2) tolerability: dose interruptions, reductions and dose intensity.

Secondary objectives and endpoints are:

(a) To evaluate the preliminary anti-tumor activity of the Compound of formula (I) in combination with ribociclib. Overall response rate (ORR), Disease control rate (DCR), Duration of response (DOR), Progression Free Survival (PFS) as per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. For dose expansion part only: Overall survival (OS), Plasma concentrations and derived PK parameters

(b) To characterize the Pharmacokinetics (PK) profile of the Compound of formula (I) and ribociclib in combination. Changes from baseline of the PD marker DUSP6 in tumor tissue.

(c) To evaluate the pharmacodynamics (PD) effect of the Compound of formula (I) and ribociclib in combination in tumor (DUSP6)

Exploratory objectives and endpoints are:

(a) To assess genetic alterations in multiple cancer related genes in tumor samples (tumor and plasma (circulating free DNA (cfDNA)) to evaluate their relationship with clinical outcomes/development of resistance. Genetic alterations in multiple cancer related genes found in tumor samples at baseline and post-dose, including at disease progression, and their relationship to clinical outcome endpoints.

(b) To further assess PD effect of the Compound of formula (I) in combination with ribociclib. Changes from baseline of PD markers in blood (e.g., DUSP6). (c) To evaluate drug-drug interaction (DDI) between the Compound of formula (I) and ribociclib. The Compound of formula (I) and ribociclib plasma concentrations and derived PK parameters.

(d) To investigate how cfDNA alterations reflect the genetic alteration of the archival and (when available) newly obtained tumor samples. Differences in genetic alterations measured in both tumor and plasma samples as a surrogate tissue from the same patient at given time points (pre-dose and post-dose).

This is a multi-center, open-label, phase lb dose escalation study followed by a dose expansion part. The Compound of formula (I) in combination with ribociclib will be administered in melanoma patients carrying NRAS mutations. The study treatment will be taken until the patient experiences unacceptable toxicity, progressive disease and/or treatment is discontinued at the discretion of the investigator or the patient or due to withdrawal of consent. A cycle is defined as 28 days.

Inclusion criteria: Adult (18 years or older) melanoma patients with diagnosis of locally advanced or metastatic NRAS-mutated melanoma who have progressed following standard of care or for whom no effective standard therapy exists, is tolerated, appropriate or is considered equivalent to study treatment will be eligible to participate in this study. Presence of NRAS mutation in tumor tissue is prior to study treatment as determined by a local laboratory or a Novartis designated central laboratory, or written documentation of KRAS, BRAF or NRAS mutation. ECOG (Eastern Cooperative Oncology Group) performance status is £ 2. Patients must have a site of disease amenable to biopsy and must be willing to undergo a new tumor biopsy at baseline and during treatment according to treating institution’s own guidelines and requirements for such procedure. Presence of at least one measurable lesion according to RECIST v1 .1 is required.

Exclusion criteria:

(a) Prior treatment with a RAF inhibitor (including any BRAF inhibitor and Raf

inhibitor) or CDK4/6 inhibitor.

(b) T reatment with any of the following anti-cancer therapies prior to the first dose of study treatment within the stated timeframes:

(i) £ 4 weeks for radiation therapy or £ 2 weeks for limited field radiation for palliation prior to the first dose of study treatment. (ii) £ 4 weeks or £ 5 half-life (whichever is shorter) for chemotherapy or biological therapy (except immunotherapy) or continuous or intermittent small molecule therapeutics or any other investigational agent.

(iii) £4 weeks for any immunotherapy treatment including immune checkpoint inhibitors.

(iv) £6 weeks for cytotoxic agents with major delayed toxicities, such as nitrosureas and mitomycin C.

(c) History or current evidence of retinal vein occlusion (RVO) or current risk factors for RVO (e.g. uncontrolled glaucoma or ocular hypertension, history of hyperviscosity or hypercoagulability syndromes).

(d) Any medical condition that would, in the investigator’s judgment, prevent the

patient’s participation in the clinical study due to safety concerns or compliance with clinical study procedures. Any severe, acute, or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation or study treatment administration or that may interfere with the interpretation of study results and, in the judgment of the investigator, would make the patient inappropriate for the study.

(e) Patients receiving treatment with medications that are known to be strong

inhibitors and/or inducers of CYP3A and CYP2C8; inhibitor or inducers of UGT2B7; substrates and inhibitors of UGT1 A1 ; substrates of CYP2C8, CYP2C9, and CYP3A with a narrow therapeutic index; and sensitive substrates of CYP3A, herb medicines known to cause liver toxicity, which cannot be discontinued 7 days prior to the start study treatment and for the duration of the study.

(f) Patients receiving proton pump inhibitors (PPI) which cannot be discontinued 3 days prior to the start study treatment and for the duration of the study.

(g) Patients with malignant disease, other than that being treated in this study.

Exceptions to this exclusion criterion include the following: malignancies that were treated curatively and have not recurred within 2 years prior to study treatment; completely resected basal cell and squamous cell skin cancers; and completely resected carcinoma in situ of any type.

Clinical efficacy will be evaluated measuring overall response rate (ORR), disease control rate (DCR), duration of response (DOR), progression free survival (PFS) as per RECIST version 1 .1 and overall survival (OS) (only in dose expansion part). Data from a dose fractionation efficacy study in Calu-6 xenografts demonstrated that across different dosing levels, the Compound of formula (I) dosed QD (qd) and fractioned twice a day (BID) showed similar levels of anti-tumor activity. These results support exploration of QD or BID dose regimen in the clinic.

Assessment of potential signs of clinical efficacy will be conducted, which includes ORR, PFS and OS assessments.

All patients enrolled during the dose escalation part of the study, will be assigned to receive the Compound of formula (I) in combination with ribociclib in order to evaluate safety and tolerability of the combinations.

The dose escalation for each tested regimen will be guided by a Bayesian logistic regression model (BLRM) based on the first cycle DLT data.

BLRM/BHLRM is a well-established method to estimate the MTD in cancer patients. The adaptive BLRM/BHLRM will be guided by the escalation with overdose control (EWOC) principle to control the risk of DLT in future patients on study. The use of Bayesian response adaptive models for small datasets has been accepted by EMEA (“Guideline on clinical trials in small populations”, February 13, 2007) and endorsed by numerous publications (Babb et al 1998, Neuenschwander et al 2008, Neuenschwander et al 2010), and its development and appropriate use is one aspect of the FDA’s Critical Path Initiative.

Patients enrolled in this expansion part will be treated at the recommended dose

combination (at MTD or lower dose combination) of the Compound of formula (I) and ribociclib.

The safety (including the dose-DLT relationship) and tolerability of the combination will be assessed; dose(s) and regimen(s) will be identified for use in the dose expansion based on the review of these data. The recommended dose for expansion will also be guided by available information on PK, PD, and preliminary anti-tumor activity.

Treatment

The study treatment will be administered in 28-day dosing cycles in fasted condition.

Tablet and capsule for oral use, dose as assigned, daily dose for 28 day cycles. The investigator or responsible site personnel should instruct the patient to take the study drug exactly as prescribed to promote compliance.

Patients should inform the investigational site staff of any missed or delayed doses. Patients may be discontinued from study treatment earlier due to unacceptable toxicity, progressive disease, if treatment is discontinued at the discretion of the investigator or the patient and/or if the patient withdraws consent.

The following table describes the starting doses and the provisional dose levels of the individual investigational drugs (not the combination) that may be evaluated during this trial.

Suggested dose levels of the combination the Compound of formula (I) and ribociclib Dose level Proposed daily dose for the Compound of formula (I)^*

-2 400 mg

-G^* 600 mg

1 800 mg (starting dose)

2 1200 mg

3 1600 mg

Dose level Proposed daily dose for ribociclib^*

-G^* 100 mg

1 200 mg (starting dose)

2 400 mg

3 600 mg

^*lt is possible for additional and/or intermediate dose levels to be added during the course of the study, including doses outside the range of provisional doses shown in this table and not exceeding the recommended dose (RD) for both single agents. Cohorts may be added at any dose level below the maximum tolerated dose (MTD) of the combination in order to better understand safety, PK or PD.

^**DL -1 represent treatment doses for patients requiring a dose reduction from the starting dose level and/or the potential starting dose depending on the safety information from FIH studies. The MTD(s) for any combination is defined as the highest dose combination for that combination that is unlikely (<25% posterior probability) to cause DLTs in 33% or more of the treated patients in the first cycle of the Compound of formula (I) and ribociclib treatment during the escalation part of the study.

The RD will be a dose that is less than or equal to MTD and has, in the view of Investigators and Novartis study personnel, the most appropriate benefit-risk assessment based on the review of safety and tolerability, PK, PD and activity information. Note that it is possible that the MTD may not be reached in some situations. The CDK4/6 inhibitor may be administered either continuously i.e. without a break during the treatment period, or with a holiday period.

For example, the CDK4/6 inhibitor, e.g. ribociclib or a pharmaceutically acceptable salt thereof, may be administered 3 weeks on and 1 week off, or 2 weeks on and 2 weeks off; preferably 3 weeks on and 1 week off. In particular, the following regimens may be used according to the present invention

b.i.d. or BID: twice a day qd or QD: once daily

Claims (26)

1 . A pharmaceutical combination of a Raf inhibitor and a CDK4/6 inhibitor, wherein the Raf inhibitor is the Compound of formula (I),

or a pharmaceutically acceptable salt thereof.

2. A pharmaceutical combination of a Raf inhibitor and a CDK4/6 inhibitor, wherein the CDK4/6 inhibitor is ribociclib, or a pharmaceutically acceptable salt thereof.

3. A pharmaceutical combination according to claim 1 , wherein

(i) the Raf inhibitor is the Compound of formula (I), or a pharmaceutically acceptable salt thereof; and

(ii) the CDK4/6 inhibitor is ribociclib, or a pharmaceutically acceptable salt thereof.

4. The pharmaceutical combination according to any one of claims 1 -3 for use in the treatment of cancer.

5. The pharmaceutical combination for use according to claim 4, wherein the cancer has an NRAS mutation.

6. The pharmaceutical combination for use according to claim 4, wherein the cancer has an KRAS mutation.

7. The pharmaceutical combination for use according to claim 4 or 5, wherein the cancer is a melanoma.

8. The pharmaceutical combination for use according to claim 7, wherein the cancer is a mutant melanoma, preferably a NRAS mutant melanoma.

9. The pharmaceutical combination for use according to claim 8, wherein the melanoma expresses at least one mutation selected from the group consisting of NRAS mutations G12C, G12R, G12D, G12V, G12S, G12A, G13R, G13D, G13C, G13A, G13, G13S, G13V, Q61 R, Q61 L, Q61 K, Q61 H, Q61 P, and Q61 E.

10. The pharmaceutical combination for use according to claim 4 or 6, wherein the

cancer is a pancreatic cancer, e.g. a pancreatic ductal adenocarcinoma (PDAC).

1 1 . The pharmaceutical combination for use according to claim 10, wherein the cancer is a mutant pancreatic cancer, e.g. a mutant PDAC, preferably a KRAS mutant PDAC.

12. The pharmaceutical combination for use according to claim 1 1 , wherein the PDAC expresses at least one mutation selected from the group consisting of KRAS mutations G12C, G12R, G12D, G12V, G12S, G12A, G13R, G13D, G13C, G13A, G13, G13S, G13V, Q61 R, Q61 L, Q61 K, Q61 H, Q61 P, and Q61 E.

13. The pharmaceutical combination for use according to any one of claims 4 to 12, wherein the two compounds, or pharmaceutically acceptable salts thereof, are administered separately, simultaneously, or sequentially.

14. The pharmaceutical combination for use according to any one of claims 4 to 13, wherein one or both compounds, or pharmaceutically acceptable salts thereof, are administered orally.

15. The pharmaceutical combination for use according to any one of claims 4 to 14, wherein the Raf inhibitor, or a pharmaceutically acceptable salt thereof, is administered at a total daily dose of about 100 mg, 200 mg, 300 mg, 400 mg, 500 mg, 600 mg, 700 mg, 800 mg, 900 mg, 1000 mg, 1 100 mg, 1200 mg, 1300 mg, 1400 mg, 1500 mg, or 1600 mg.

16. The pharmaceutical combination for use according to any one of claims 4 to 15, wherein the Raf inhibitor is administered once per day or twice per day.

17. The pharmaceutical combination for use according to any one of claims 4 to 16, wherein the Raf inhibitor is administered continuously during the treatment period.

18. The pharmaceutical combination for use according to any one of claims 4 to 17, wherein the CDK4/6 inhibitor, or a pharmaceutically acceptable salt thereof, is administered at a total daily dose of about 100 mg, 150 mg, 200 mg, 250 mg, 300 mg, 350 mg, 400 mg, 450 mg, 500 mg, 550 mg, or 600 mg.

19. The pharmaceutical combination for use according to any one of claims 4 to 18, wherein the CDK4/6 inhibitor is administered once per day or twice per day.

20. The pharmaceutical combination for use according to any one of claims 4 to 19, wherein the CDK4/6 inhibitor is administered with a drug holiday period, for example three weeks on, and one week off.

21 . The pharmaceutical combination according to any one of claims 1 -3 for use in the treatment of mutant melanoma, preferably NRAS mutant melanoma, expressing at least one mutation selected from the group consisting of NRAS mutations G12C, G12R, G12D, G12V, G12S, G12A, G13R, G13D, G13C, G13A, G13, G13S, G13V, Q61 R, Q61 L, Q61 K, Q61 H, Q61 P, Q61 E, or mutant pancreatic cancer, e.g. a mutant PDAC, preferably a KRAS mutant PDAC, expressing at least one mutation selected from the group consisting of KRAS mutations G12C, G12R, G12D, G12V, G12S, G12A, G13R, G13D, G13C, G13A, G13, G13S, G13V, Q61 R, Q61 L, Q61 K, Q61 H, Q61 P, Q61 E, wherein the Raf inhibitor, or a pharmaceutically acceptable salt thereof, is administered at a daily dose of about 600 mg bid, and wherein the CDK4/6 inhibitor, or a pharmaceutically acceptable salt thereof, is administered at a daily dose of about 600 mg qd.

22. The pharmaceutical combination according to any one of claims 1 -3 for use in the treatment of mutant melanoma, preferably NRAS mutant melanoma, expressing at least one mutation selected from the group consisting of NRAS mutations G12C, G12R, G12D, G12V, G12S, G12A, G13R, G13D, G13C, G13A, G13, G13S, G13V, Q61 R, Q61 L, Q61 K, Q61 H, Q61 P, Q61 E, or mutant pancreatic cancer, e.g. a mutant PDAC, preferably a KRAS mutant PDAC, expressing at least one mutation selected from the group consisting of KRAS mutations G12C, G12R, G12D, G12V, G12S, G12A, G13R, G13D, G13C, G13A, G13, G13S, G13V, Q61 R, Q61 L, Q61 K, Q61 H, Q61 P, Q61 E, wherein the Raf inhibitor, or a pharmaceutically acceptable salt thereof, is administered continuoussly at a daily dose of about 600 mg bid, and wherein the CDK4/6 inhibitor, or a pharmaceutically acceptable salt thereof, is administered at a daily dose of about 600 mg qd, three weeks on and one week off.

23. Use of the pharmaceutical combination according to any one of claims 1 -3 for the preparation of a medicament for the treatment of cancer.

24. A method for treating cancer in a subject in need thereof comprising administering to the subject a therapeutically effective amount of the pharmaceutical combination according to any one of claims 1 -3.

25. The Compound of formula (I)

or a pharmaceutically acceptable salt thereof, for use in treating cancer by co administration with ribociclib, or a pharmaceutically acceptable salt thereof.

26. Ribociclib, or a pharmaceutically acceptable salt thereof, for use in treating cancer by co-administration with the Compound of formula (I), or a pharmaceutically acceptable salt thereof.