1,2,4-oxadiazole and 1 ,2,4-thiadiazole compounds of formula (I):
PREDICTED AUPM 170, CA 170, AUPM-170, CA-170
WATCH THIS SPACE
Aurigene Discovery Technologies Limited INNOVATOR
Curis with the option to exclusively license Aurigene’s orally-available small molecule antagonist of programmed death ligand-1 (PD-L1) in the immuno-oncology field
Addressing immune checkpoint pathways is a well validated strategy to treat human cancers and the ability to target PD-1/PD-L1 and other immune checkpoints with orally available small molecule drugs has the potential to be a distinct and major advancement for patients.
Through its collaboration with Aurigene, Curis is now engaged in the discovery and development of the first ever orally bioavailable, small molecule antagonists that target immune checkpoint receptor-ligand interactions, including PD-1/PD-L1 interactions. In the first half of 2016, Curis expects to file an IND application with the U.S. FDA to initiate clinical testing of CA-170, the first small molecule immune checkpoint antagonist targeting PD-L1 and VISTA. The multi-year collaboration with Aurigene is focused on generation of small molecule antagonists targeting additional checkpoint receptor-ligand interactions and Curis expects to advance additional drug candidates for clinical testing in the coming years. The next immuno-oncology program in the collaboration is currently targeting the immune checkpoints PD-L1 and TIM3.
In November 2015, preclinical data were reported. Data demonstrated tha the drug rescued and sustained activation of T cells functions in culture. CA-170 resulted in anti-tumor activity in multiple syngeneic tumor models including melanoma and colon cancer. Similar data were presented at the 2015 AACR-NCI-EORTC Molecular Targets and Cancer Therapeutics Conference in Boston, MA
By August 2015, preclinical data had been reported. Preliminary data demonstrated that in in vitro studies, small molecule PD-L1 antagonists induced effective T cell proliferation and IFN-gamma production by T cells that were specifically suppressed by PD-L1 in culture. The compounds were found to have effects similar to anti-PD1 antibodies in in vivo tumor models
(Oral Small Molecule PD-L1/VISTAAntagonist)
Certain human cancers express a ligand on their cell surface referred to as Programmed-death Ligand 1, or PD-L1, which binds to its cognate receptor, Programmed-death 1, or PD-1, present on the surface of the immune system’s T cells. Cell surface interactions between tumor cells and T cells through PD-L1/PD-1 molecules result in T cell inactivation and hence the inability of the body to mount an effective immune response against the tumor. It has been previously shown that modulation of the PD-1 mediated inhibition of T cells by either anti-PD1 antibodies or anti-PD-L1 antibodies can lead to activation of T cells that result in the observed anti-tumor effects in the tumor tissues. Therapeutic monoclonal antibodies targeting the PD-1/PD-L1 interactions have now been approved by the U.S. FDA for the treatment of certain cancers, and multiple therapeutic monoclonal antibodies targeting PD-1 or PD-L1 are currently in development.
In addition to PD-1/PD-L1 immune regulators, there are several other checkpoint molecules that are involved in the modulation of immune responses to tumor cells1. One such regulator is V-domain Ig suppressor of T-cell activation or VISTA that shares structural homology with PD-L1 and is also a potent suppressor of T cell functions. However, the expression of VISTA is different from that of PD-L1, and appears to be limited to the hematopoietic compartment in tissues such as spleen, lymph nodes and blood as well as in myeloid hematopoietic cells within the tumor microenvironment. Recent animal studies have demonstrated that combined targeting/ blockade of PD-1/PD-L1 interactions and VISTA result in improved anti-tumor responses in certain tumor models, highlighting their distinct and non-redundant functions in regulating the immune response to tumors2.
As part of the collaboration with Aurigene, in October 2015 Curis licensed a first-in-class oral, small molecule antagonist designated as CA-170 that selectively targets PD-L1 and VISTA, both of which function as negative checkpoint regulators of immune activation. CA-170 was selected from the broad PD-1 pathway antagonist program that the companies have been engaged in since the collaboration was established in January 2015. Preclinical data demonstrate that CA-170 can induce effective proliferation and IFN-γ (Interferon-gamma) production (a cytokine that is produced by activated T cells and is a marker of T cell activation) by T cells that are specifically suppressed by PD-L1 or VISTA in culture. In addition, CA-170 also appears to have anti-tumor effects similar to anti-PD-1 or anti-VISTA antibodies in multiple in vivo tumor models and appears to have a good in vivo safety profile. Curis expects to file an IND and initiate clinical testing of CA-170 in patients with advanced tumors during the first half of 2016.
Curis and Aurigene Announce Collaboration, License and Option Agreement to Discover, Develop and Commercialize Small Molecule Antagonists for Immuno-Oncology and Precision Oncology Targets
— Agreement Provides Curis with Option to Exclusively License Aurigene’s Antagonists for Immuno-Oncology, Including an Antagonist of PD-L1 and Selected Precision Oncology Targets, Including an IRAK4 Kinase Inhibitor —
— Investigational New Drug (IND) Application Filings for Both Initial Collaboration Programs Expected this Year —
— Curis to issue 17.1M shares of its Common Stock as Up-front Consideration —
— Management to Host Conference Call Today at 8:00 a.m. EST —
LEXINGTON, Mass. and BANGALORE, India, Jan. 21, 2015 (GLOBE NEWSWIRE) — Curis, Inc. (Nasdaq:CRIS), a biotechnology company focused on the development and commercialization of innovative drug candidates for the treatment of human cancers, and Aurigene Discovery Technologies Limited, a specialized, discovery stage biotechnology company developing novel therapies to treat cancer and inflammatory diseases, today announced that they have entered into an exclusive collaboration agreement focused on immuno-oncology and selected precision oncology targets. The collaboration provides for inclusion of multiple programs, with Curis having the option to exclusively license compounds once a development candidate is nominated within each respective program. The partnership draws from each company’s respective areas of expertise, with Aurigene having the responsibility for conducting all discovery and preclinical activities, including IND-enabling studies and providing Phase 1 clinical trial supply, and Curis having responsibility for all clinical development, regulatory and commercialization efforts worldwide, excluding India and Russia, for each program for which it exercises an option to obtain a license.
The first two programs under the collaboration are an orally-available small molecule antagonist of programmed death ligand-1 (PD-L1) in the immuno-oncology field and an orally-available small molecule inhibitor of Interleukin-1 receptor-associated kinase 4 (IRAK4) in the precision oncology field. Curis expects to exercise its option to obtain exclusive licenses to both programs and file IND applications for a development candidate from each in 2015.
“We are thrilled to partner with Aurigene in seeking to discover, develop and commercialize small molecule drug candidates generated from Aurigene’s novel technology and we believe that this collaboration represents a true transformation for Curis that positions the company for continued growth in the development and eventual commercialization of cancer drugs,” said Ali Fattaey, Ph.D., President and Chief Executive Officer of Curis. “The multi-year nature of our collaboration means that the parties have the potential to generate a steady pipeline of novel drug candidates in the coming years. Addressing immune checkpoint pathways is now a well validated strategy to treat human cancers and the ability to target PD-1/PD-L1 and other immune checkpoints with orally available small molecule drugs has the potential to be a distinct and major advancement for patients. Recent studies have also shown that alterations of the MYD88 gene lead to dysregulation of its downstream target IRAK4 in a number of hematologic malignancies, including Waldenström’s Macroglobulinemia and a subset of diffuse large B-cell lymphomas, making IRAK4 an attractive target for the treatment of these cancers. We look forward to advancing these programs into clinical development later this year.”
Dr. Fattaey continued, “Aurigene has a long and well-established track record of generating targeted small molecule drug candidates with bio-pharmaceutical collaborators and we have significantly expanded our drug development capabilities as we advance our proprietary drug candidates in currently ongoing clinical studies. We believe that we are well-positioned to advance compounds from this collaboration into clinical development.”
CSN Murthy, Chief Executive Officer of Aurigene, said, “We are excited to enter into this exclusive collaboration with Curis under which we intend to discover and develop a number of drug candidates from our chemistry innovations in the most exciting fields of cancer therapy. This unique collaboration is an opportunity for Aurigene to participate in advancing our discoveries into clinical development and beyond, and mutually align interests as provided for in our agreement. Our scientists at Aurigene have established a novel strategy to address immune checkpoint targets using small molecule chemical approaches, and have discovered a number of candidates that modulate these checkpoint pathways, including PD-1/PD-L1. We have established a large panel of preclinical tumor models in immunocompetent mice and can show significant in vivo anti-tumor activity using our small molecule PD-L1 antagonists. We are also in the late stages of selecting a candidate that is a potent and selective inhibitor of the IRAK4 kinase, demonstrating excellent in vivo activity in preclinical tumor models.”
In connection with the transaction, Curis has issued to Aurigene approximately 17.1 million shares of its common stock, or 19.9% of its outstanding common stock immediately prior to the transaction, in partial consideration for the rights granted to Curis under the collaboration agreement. The shares issued to Aurigene are subject to a lock-up agreement until January 18, 2017, with a portion of the shares being released from the lock-up in four equal bi-annual installments between now and that date.
The agreement provides that the parties will collaborate exclusively in immuno-oncology for an initial period of approximately two years, with the option for Curis to extend the broad immuno-oncology exclusivity.
In addition Curis has agreed to make payments to Aurigene as follows:
- for the first two programs: up to $52.5 million per program, including $42.5 million per program for approval and commercial milestones, plus specified approval milestone payments for additional indications, if any;
- for the third and fourth programs: up to $50 million per program, including $42.5 million per program for approval and commercial milestones, plus specified approval milestone payments for additional indications, if any; and
- for any program thereafter: up to $140.5 million per program, including $87.5 million per program in approval and commercial milestones, plus specified approval milestone payments for additional indications, if any.
Curis has agreed to pay Aurigene royalties on any net sales ranging from high single digits to 10% in territories where it successfully commercializes products and will also share in amounts that it receives from sublicensees depending upon the stage of development of the respective molecule.
About Immune Checkpoint Modulation and Programmed Death 1 Pathway
Modulation of immune checkpoint pathways has emerged as a highly promising therapeutic approach in a wide range of human cancers. Immune checkpoints are critical for the maintenance of self-tolerance as well as for the protection of tissues from excessive immune response generated during infections. However, cancer cells have the ability to modulate certain immune checkpoint pathways as a mechanism to evade the immune system. Certain immune checkpoint receptors or ligands are expressed by various cancer cells, targeting of which may be an effective strategy for generating anti-tumor activity. Some immune-checkpoint modulators, such as programmed death 1 (PD-1) protein, specifically regulate immune cell effector functions within tissues. One of the mechanisms by which tumor cells block anti-tumor immune responses in the tumor microenvironment is by upregulating ligands for PD-1, such as PD-L1. Hence, targeting of PD-1 and/or PD-L1 has been shown to lead to the generation of effective anti-tumor responses.
About Curis, Inc.
Curis is a biotechnology company focused on the development and commercialization of novel drug candidates for the treatment of human cancers. Curis’ pipeline of drug candidates includes CUDC-907, a dual HDAC and PI3K inhibitor, CUDC-427, a small molecule antagonist of IAP proteins, and Debio 0932, an oral HSP90 inhibitor. Curis is also engaged in a collaboration with Genentech, a member of the Roche Group, under which Genentech and Roche are developing and commercializing Erivedge®, the first and only FDA-approved medicine for the treatment of advanced basal cell carcinoma. For more information, visit Curis’ website at www.curis.com.
Aurigene is a specialized, discovery stage biotechnology company, developing novel and best-in-class therapies to treat cancer and inflammatory diseases. Aurigene’s Programmed Death pathway program is the first of several immune checkpoint programs that are at different stages of discovery and preclinical development. Aurigene has partnered with several large- and mid-pharma companies in the United States and Europe and has delivered multiple clinical compounds through these partnerships. With over 500 scientists, Aurigene has collaborated with 6 of the top 10 pharma companies. Aurigene is an independent, wholly owned subsidiary of Dr. Reddy’s Laboratories Ltd. (NYSE:RDY). For more information, please visit Aurigene’s website at http://aurigene.com/.
WO2011161699, WO2012/168944, WO2013144704 and WO2013132317 report peptides or peptidomimetic compounds which are capable of suppressing and/or inhibiting the programmed cell death 1 (PD1) signaling pathway.
Example 5: Synthesis of
The compound was synthesised using similar procedure as depicted in Example 4 (compound 4) using D-amino acids are linked up in reverse order. Boc-D-Thr(‘Bu)-OH was used in place of Boc-Ser(‘Bu)-OH, Fmoc-D-Asn(trt)-OH in place of Fmoc-Asn(trt)-OH and H-D-Ser(‘Bu)-0’Bu was used in place of H-Thr^Bu^O’Bu to yield 0.3 g crude material of the title compound. The cmde solid material was purified using preparative HPLC described under experimental conditions. LCMS: 361.3 (M+H)+. HPLC: tR = 13.58 min.
Example 8: Synthesis of
The compound was synthesised using similar procedure as depicted in Example 2 (compound 2) using Fmoc-Glu(0’Bu)-OH instead of Fmoc-Asn(Trt)-OH to get 0.4 g crude material of the title compound. The crude solid material was purified using preparative HPLC described under experimental conditions. LCMS: 362.1 (M+H)+. HPLC: tR = 13.27 min.
Example 3: Synthesis of compound 3
Lawesson’s reagent (2.85 g, 7.03 mmol) was added to a solution of compound 2e (4 g, 4.68 mmol) in THF (40 mL) and stirred at 75°C for 4 h. The completeness of the reaction was confirmed by TLC analysis. The reaction mixture was evaporated under reduced
pressure and the obtained residue was partitioned between ice water and ethyl acetate. The organic layer was washed with NaHCC>3 solution followed brine solution. The organic layer was dried over Na2S04, filtered and evaporated under reduced pressure to get residue which was further purified by silica gel column chromatography (eluent: 0-5% ethyl acetate in hexane) to afford 2.7 g of compound 3a (Yield: 67.66%). LCMS: 852.3 (M+H)+,
Fmoc group on compound 3a was deprotected by adding diethylamine (3.8 mL) to the solution of compound 3a (1 g, 1.17 mmol) in CH2CI2 (3.8 mL). The reaction mixture was stirred at room temperature for 30 min. The resulting solution was concentrated in vacuum to get a thick gummy residue. The crude compound was purified by neutral alumina column chromatography (eluent: 0-50% ethyl acetate in hexane then 0-5% methanol in chloroform) to attain 0.62 g of compound 3b. LCMS: 630.5 (M+H)+.
To a solution of compound 3b (0.6 g) in CH2CI2 (7.5 mL), trifluoroacetic acid (2.5 mL) and catalytic amount of triisopropylsilane were added and stirred at room temperature for 3 h. The resulting solution was concentrated in vacuum to get 0.13 g of compound 3 which was purified by preparative HPLC method described under experimental conditions. LCMS: 232.3 (M+H)+.
Example 1: Synthesis of compound 1
Potassium carbonate (7.9 g, 57.39 mmol) and Methyl iodide (1.3 mL, 21.04 mmol) were added to a solution of compound la (5.0 g, 19.13 mmol) in DMF (35 mL) and stirred at room temperature for 2 h. The completeness of the reaction was confirmed by TLC analysis. The reaction mixture was partitioned between water and ethyl acetate. Organic layer was washed with water, brine, dried over Na2S04 and evaporated under reduced pressure to get 5.0 g of compound lb (Yield: 96.1%). LCMS: 176.1 (M-Boc)+.
Hydrazine hydrate (7.2 mL) was added to a solution of compound lb (5.0 g, 18.16 mmol) in methanol (30 mL) and stirred at room temperature for 2 h. The completeness of the reaction was confirmed by TLC analysis. The reaction mixture was evaporated under reduced pressure, the residue obtained was partitioned between water and ethyl acetate. Organic layer was washed with water, brine, dried over Na2S04 and evaporated under reduced pressure to get 4.0 g of compound lc (Yield: 80.0%). LCMS: 276.3 (M+H)+. Step lc:
NMM (0.67 ml, 6.52 mmol) was slowly added to a stirred solution of lc (1.2 g, 4.35 mmol), Id (1.43 g, 4.35 mmol), HOBt (0.7 g, 5.22 mmol) and EDC.HC1 (0.99 g, 5.22 mmol) in DMF (15 mL) at 0°C. The reaction mixture was stirred at room temperature for 12 h. The completeness of the reaction was confirmed by TLC analysis. The reaction was quenched with ice and the solid precipitated was filtered and dried under vacuum to obtain 2.0 g of pure product le (Yield: 83.3%). LCMS: 591.5 (M+Na)+.
To a stirred solution of le (1.5 g, 2.63 mmol) in dry THF (15.0 mL) and DMF (5.0 mL) triphenylphosphine (1.38 g, 5.27 mmol) and iodine (1.33 g, 5.27 mmol) were added at 0°C. After the iodine was completely dissolved, Et3N (1.52 mL, 10.54 mmol) was added to this reaction mixture at ice cold temperature. Reaction mixture was allowed to attain room temperature and stirred for 4 h. The completeness of the reaction was confirmed by TLC analysis. The reaction was quenched with ice water and extracted with ethyl acetate. Organic layer was washed with saturated sodium thiosulphate and brine solution.
The separated Organic layer was dried over Na2SC>4 and evaporated under reduced pressure to get residue, which was further purified by silica gel column chromatography (eluent: 30% ethyl acetate in hexane) to afford 0.8 g of compound If (Yield: 55%). LCMS: 551.3 (M+H)+.
1f i g
Fmoc group was deprotected by the addition of diethylamine (20.0 mL) to a solution of compound If (0.8 g, 1.45 mmol) in CH2CI2 (20.0 mL) at 0°C. The reaction was stirred at room temperature for 2 h. The resulting solution was concentrated in vacuum to get a thick gummy residue. The crude compound was purified by neutral alumina column chromatography (eluent: 2% methanol in chloroform) to afford 0.38 g of compound lg (Yield: 80.0%): LCMS: 329.4 (M+H)+.
ig 1 i
Compound lg (0.38 g, 1.16 mmol), TEA (0.33 mL, 2.32 mmol) dissolved in DMF (10 mL) were added drop wise to a solution of lh (0.55 g, 1.39 mmol) at 0°C for urea bond formation and the mixture was stirred at room temperature for 2 h. The completeness of the reaction was confirmed by TLC analysis. The reaction was quenched with ice water, the solid precipitated was filtered and dried under vacuum to get crude compound, which was further purified by silica gel column chromatography (eluent: 0-35% ethyl acetate in hexane) to get 0.4 g of product li (Yield: 59.7%). LCMS: 586.4 (M+H)+.
BocHN’ IJ, H LT Y~™
To a solution of compound li (0.4 g, 0.68 mmol) in CH2CI2 (5 m L), trifluoro acetic acid (5 mL) and catalytic amount of triisopropylsilane were added and stirred at room temperature for 3 h to remove the acid sensitive protecting groups. The resulting solution was concentrated under nitrogen and the solid material was purified by preparative HPLC method as described under experimental conditions (Yield: 0.05 g). LCMS: 318.0 (M+H)+; HPLC: tR= 10.96 min.
Synthesis of compound lh (N02-C6H4-OCO-Thr(tBu)- 0¾u):
To a solution of 4-nitrophenylchloroformate (4.79 g, 23.77 mmol) in DCM (25.0 mL) was added a solution of H-Thr(tBu)-OtBu (5.0 g, 21.61 mmol) TEA (6.2 mL, 43.22 mmol) in CH2CI2 (25 mL) slowly at 0°C and allowed to stir for 30 min. The completion of the reaction was confirmed by TLC analysis. After completion of reaction it was diluted with DCM and washed with 1.0 M of citric acid followed by 1.0 M sodium carbonate solution. The organic layer was dried over Na2S04 and evaporated under reduced pressure to afford crude compound 1 h, which was further purified by silica gel column chromatography (eluent: 0-5% ethyl acetate in hexane) to get 3.0 g of product lh. jH NMR (CDCI3, 400 MHz): £1.17 (s, 9H), 1 .28 (d, 3H), .50 (s, 9H), 4.11 (m, 1 H), 4.28 (m, 1H , 5.89 (d, 1H), 7.37 (d, 2H), 8.26 (d, 2H).
Brahma Reddy V, Thomas Antony, Murali Ramachandra, Venkateshwar Rao G, Wesley Roy Balasubramanian, Kishore Narayanan, Samiulla DS, Aravind AB, and Shekar Chelur.
|WO2011161699A2||27 Jun 2011||29 Dec 2011||Aurigene Discovery Technologies Limited||Immunosuppression modulating compounds|
|WO2012168944A1||21 Dec 2011||13 Dec 2012||Aurigene Discovery Technologies Limited||Therapeutic compounds for immunomodulation|
|WO2013132317A1||4 Mar 2013||12 Sep 2013||Aurigene Discovery Technologies Limited||Peptidomimetic compounds as immunomodulators|
|WO2013144704A1||28 Mar 2013||3 Oct 2013||Aurigene Discovery Technologies Limited||Immunomodulating cyclic compounds from the bc loop of human pd1|
////////Curis and Aurigene, AUPM 170, CA 170, AUPM-170, CA-170, PD-L1, VISTA antagonist