Anti-Tumor Activity of Glutaminase Inhibitor CB-839 in Solid Tumor Malignancies

Transcription

1 Anti-Tumor Activity of Glutaminase Inhibitor CB-839 in Solid Tumor Malignancies Francesco Parlati, Ph.D. Calithera Biosciences Keystone Tumor Metabolism January 25, 218

2 Disclosure I am an employee and shareholder at Calithera Biosciences

3 Agenda Introduction to CB-839 CB-839 combination with signal transduction inhibitors CB-839 combination with taxol in TNBC Novel combination strategies with CB-839 CDK4/6 and PARP inhibitors

4 Agenda Introduction to CB-839 CB-839 combination with signal transduction inhibitors CB-839 combination with taxol in TNBC Novel combination strategies CDK4/6 and PARP inhibitors

5 Cancer vs. Normal Cell Metabolism Normal Cells GLUCOSE Cancer Cells GLUCOSE Pyruvate Lactate Pyruvate Lactate Mitochondrion Mitochondrion TCA Cycle α-kg TCA Cycle α-kg Glutamate Glutamate Glutaminase Glutaminase Intermediates for biosynthesis Glutathione GLUTAMINE CB-839 GLUTAMINE

6 CB-839 Suppresses Metabolic Pathways Downstream of Glutamate in vitro F o l d C h a n g e i n M e t a b o l i t e CB-839 glutathione glutamine glutamate Glutaminase fumarate a-ketoglutarate (a-kg) TCA cycle malate oxaloacetate citrate glutamate a-kg NSCLC* 24 h treatment 1 mm CB-839 aspartate G l u t a m i n e G l u t a m a t e G S H M a l a t e C i t r a t e A s p a r t a t e * Average of 4 cell lines 6

7 n o r m a l t u m o r n o r m a l t u m o r n o r m a l t u m o r n o r m a l t u m o r m R N A e x p r e s s i o n ( l o g 2 ) Glutaminase is Overexpressed in Solid Tumors Expression of GAC isoform in Clinical Samples T N B C c c R C C N S C L C m e l a n o m a p =. 7 * * * * * * * * * * mrna levels were obtained from Compendia Bioscience Translational Bioinformatics Services (Life Technologies, Ann Arbor, MI)

8 Increasing effect of CB-839 CB-839 Has Broad Anti-tumor Activity Across Multiple Tumor Cell Lines Triple Negative Breast Cancer Renal Cell Carcinoma Non-Small Cell Lung Cancer 1 Melanoma no drug effect % cell growth complete growth suppression % cell death complete killing Panel of Tumor Cell Lines Treated with CB-839 (1 mm) for 72 Hours Effects of CB-839 on the growth/death of a panel of cancer cell lines % cell growth compared to untreated cells % cell death compared to starting cell number

9 H S c o r e High Levels of GLS Expression in Patients On-study or Archival Tumor Samples Triple Negative Breast Cancer Renal Cell Carcinoma Non-Small Cell Lung Cancer Melanoma G l u t a m i n a s e E x p r e s s i o n ( I H C ) h i g h e s t e x p r e s s i o n l o w e s t e x p r e s s i o n T N B C R C C N S C L C m e l a n o m a Tumor FFPE stained with a-gls antibody

10 CB-839 Monotherapy in Patients Well tolerated at active doses MTD not reached 8 mg PO BID selected as RP2D Clear PK/PD relationship Glutaminase inhibition tested in patients with solid tumors (n=88) Sustained and near-complete inhibition of glutaminase in platelets and tumors CB-839 monotherapy was active in RCC pts (n=21) 1 PR; on study 356 days 52% SD, 2 longest ongoing at 25 mo and 15 mo Pharmacodynamic Glutaminase Inhibition Platelets Tumors G l u t a m i n a s e A c t i v i t y % G l u t a m i n a s e A c t i v i t y ( n m o l / m i n / m g p r o t e i n ) L L O Q [ C B h ] ( n g / m L ) U n i n h i b i t e d I n h i b i t e d % % % % 1 T I D 1 5 T I D 2 5 T I D 4 T I D 6 T I D 6 B I D B I D T I D Tumor GIST NSCLC colon meso RCC C1D15 AUC (-8h) (ng*hr/ml) e x v i v o p l a t e l e t d o s e r e s p o n s e % C1D1 4 hours post dose Approximately 3 weeks on study drug Meric-Bernstam F. et. al, European Journal of Cancer, Vol. 69, S12 S13

11 Agenda Introduction to CB-839 CB-839 combination with signal transduction inhibitors CB-839 combination with taxol in TNBC Novel combination strategies CDK4/6 and PARP inhibitors

12 CB-839 is Synergistic with Growth Factor Signaling Pathway Inhibitors Signal Transduction inhibitors indirectly decrease glucose and glutamine utilization CB-839 is synergistic with multiple growth factor signaling pathway inhibitors Erlotinib (EGFRi) Crizotinib (ALKi/ROSi) Growth Factor Receptor Cabozantinib (VEGFRi/METi) Ras/Raf Pathway PI3K/mTOR Pathway Everolimus (mtori) CB-839 Glutamine Utilization Glucose Utilization = Inhibition Metabolic Rewiring Supporting Tumor Growth 12

13 Synergistic Anti-Proliferative Activity of CB-839 and Everolimus in Renal Clear Cell Carcinoma N u trie n t C o n s u m p tio n (r e la tiv e to D M S O ) C e ll S u rv iv a l (r e a ltiv e to D M S O ) A C H N 72 h Treatment Plating Density CB-839 (nm) Everolimus (nm) Mixture (Comb. Index) G lu c o s e C o n s u m p tio n G lu ta m in e C o n s u m p tio n 1. D M S O.5 C B E v e ro lim u s C o m b o. 24 h Treatment

14 CB-839 Enhances the Anti-tumor Activity of Signal Transduction Inhibitors T u m o r V o l u m e ( m m 3 ) T u m o r V o l u m e ( m m 3 ) Everolimus Combination Cabozantinib Combination 1 5 V e h i c l e 1 4 V e h i c l e RCC Caki-1 xenograft T u m o r V o l u m e ( m m 3 ) C B E v e r o l i m u s C o m b o D o s i n g s t a r t * * * T u m o r V o l u m e ( m m 3 ) C B C a b o z a n t in ib C o m b o D o s i n g s t a r t * RCC Caki-1 xenograft D a y P o s t I m p l a n t D a y P o s t I m p l a n t Crizotinib Combination Erlotinib Combination 1 V e h i c l e 2 V e h i c l e C B C B C r i z o t in ib C o m b o 1 5 E r l o t i n ib C o m b o NSCLC H2228 xenograft 5 D o s i n g s t a r t 1 D o s i n g s t a r t NSCLC HCC827 xenograft * * 5 * * * * D a y s P o s t I m p l a n t D a y P o s t I m p l a n t

15 CB Everolimus in RCC Phase 1b Dose escalation and expansion Escalation in Advanced RCC Expansion in clear cell and papillary RCC 15

16 Survival Probability (%) Everolimus median PFS CB Everolimus in RCC Clinical Outcomes in Phase 1b Median PFS is 8.5 mo * ^ Months Median PFS (95% C.I.) 8.5 mo ( mo) Number at risk: N=17 patients (14 ccrcc and 3 papillary RCC) ^ Motzer et al, NEJM 215 * Choueiri et al, NEJM 215 Meric-Bernstam F. et. al, European Journal of Cancer, Vol. 69, S12 S13

17 Clinical Studies in RCC with CB-839 Phase 2: CB Everolimus vs. Everolimus Placebo control double blind study in RCC patients Phase 1b: CB Cabozantinib in RCC patients Phase 1/2: CB Nivolumab in RCC patients Combination Partner Ph 2: Renal Cell Carcinoma Everolimus Ph 1b: Renal Cell Carcinoma Cabozantinib Ph 1/2: Renal Cell Carcinoma Nivolumab

18 Agenda Introduction to CB-839 CB-839 combination with signal transduction inhibitors CB-839 combination with taxol in TNBC Novel combination strategies CDK4/6 and PARP inhibitors

19 Increasing effect of CB-839 CB-839 Has Broad Anti-tumor Activity Across Multiple Tumor Cell Lines % c e l l g r o w t h % c e l l d e a t h T N B C R C C N S C L C M e l a n o m a 1 n o d r u g e f f e c t c o m p l e t e g r o w t h s u p p r e s s i o n c o m p l e t e k i l l i n g Panel of Tumor Cell Lines Treated with CB-839 (1 mm) for 72 Hours Effects of CB-839 on the growth/death of a panel of cancer cell lines % cell growth compared to untreated cells % cell death compared to starting cell number

20 CB-839 in TNBC Patients Monotherapy CB-839 was well tolerated in TNBC patients 19 patients were treated 3 patients had stable disease 2 patients with stable disease greater than 8 months

21 CB-839 plus Paclitaxel Exacerbates Cell Cycle Defect in TNBC cells R e l a t i v e C e l l G r o w t h % C e l l s Paclitaxel targets tubulin and blocks cell cycle progression at mitosis (G2/M-phase) CB-839 treatment causes cells to accumulate in G1 or S-phase The combination of CB-839 plus paclitaxel causes cells to accumulate in G2/M or S-phase Synergy between CB-839 and Paclitaxel in 8 out of 11 TNBC cell lines J I M T - 1 J I M T % G 2 / M % S. 5 5 % G CB-839 (nm) Paclitaxel (nm) Combination Index D M S O C B P a c l i t a x e l C o m b o 21

22 T u m o r V o l u m e ( m m 3 ) CB-839 plus Paclitaxel Shows Enhanced Anti-tumor Activity In Vivo T u m o r V o l u m e ( m m 3 ) T N B C T N B C J I M T - 1 X e n o g r a f t J I M T - 1 X e n o g r a f t 1 5 V e h i c l e C B , B I D P a c l i t a x e l, I P Q O D x 5 V e h i c l e C B , B I D C o m b o 6 P a c l i t a x e l, I V Q O D x 5 C o m b o 1 * * v s v e h i c l e * v s p a c l i t a x e l * * v s p a c l i t a x e l S t u d y D a y S t u d y d a y 22

23 CB Paclitaxel in TNBC Study Design CB mg BID Paclitaxel 8 mg/m 2 IV D1,8,15 Q28 Advanced TNBC Expansion in TNBC pts with and without prior taxane in the metastatic setting 23

24 CB Paclitaxel in TNBC Key Demographics Median of 3 prior lines of therapy for metastatic disease 35% 5L therapy Prior taxane exposure 88% any line of therapy 51% advanced/metastatic 37% adjuvant/neoadjuvant Kalinsky et al. SABCS

25 CB Paclitaxel in TNBC Best Change in Target Lesions % c h a n g e i n t a r g e t t u m o r s P r i o r T a x a n e [ A d v / M e t ] P r i o r T a x a n e [ N e o / A d j o n l y ] N o P r i o r T a x a n e D o s e ( m g ) Patients were dosed with CB mg BID and Paclitaxel 8 mg/m 2 IV D1,8,15 Q28 Kalinsky et al. SABCS

26 CB Paclitaxel in TNBC Response Table CB mg dose Patients: Total Enrolled (N) RECIST Evaluable [N (%)]* PR SD PD DCR (CR + PR + SD) Lines of Prior Adv/Met Therapy By CB-839 Dose 4 mg 6 mg (22) 3 (43) 14 (38) 4 (57) 15 (41) 3 (43) 22 (59) 3 4 Adv/ Met^ By Prior Taxane ( 6 mg) Neo/ Adj only None (2) 3 (21) 1 (33) 7 (35) 5 (36) 2 (67) 9 (45) 6 (43) 11 (55) 8 (57) 3 (1) *pts receiving a post-baseline tumor assessment, discontinued due to drug-related AE, or died due to disease having received 16 days of treatment ^Includes 3 pts that progressed on neo-adjuvant taxane therapy Kalinsky et al. SABCS

27 Molecular Subtyping of TNBC Patients on CB Pacitaxel Combination RNA expression analysis typically used to subtype TNBC tumors: TNBC-type: Tumor-intrinsic and tumor-extrinsic gene signature 6 subtypes identified (LAR, BL1, BL2, M, MSL, IM) Stroma-Axis: Tumor-extrinsic gene signature 4 subtypes identified (T, B, E, D)

28 Trend between Clinical Benefit and LAR Subtype in TNBC Patients on CB Pacitaxel No Clinical Benefit Clinical Benefit Trend between clinical benefit (PR or SD> 4 mo): LAR subtype (3 of 6 patients w/benefit; of 7 w/o benefit) Expression of androgen receptor and several metabolic enzymes e.g. TCA cycle, GSH biosynthesis, amino acid metabolism TNBC-Type LAR LAR MSL IM LAR M IM M M BL2 IM BL2 BL1 BL1 BL1 IM P R S D P D Kalinsky et al. SABCS 217 T i m e o n S t u d y ( M o n t h s ) 28

29 No Clinical Benefit Clinical Benefit Trend between Clinical Benefit and Stroma Axis D in TNBC Patients on CB Paclitaxel Stromal axis D high subtype 5 of 6 pts with high stromal D had clinical benefit Characterized by expression of collagens and collagen modifying enzymes associated with desmoplasia Recent publication linking collagen production by fibroblasts to glutaminolysis Stroma-D Score High High High Intermed High High Intermed Low Low Intermed Intermed High Low Low Low Low P R S D P D Kalinsky et al. SABCS T i m e o n S t u d y ( M o n t h s ) 29

30 Summary Combination of CB-839 with Paclitaxel CB-839 is well tolerated in combination with paclitaxel in TNBC patients Clinical benefit demonstrated in heavily pre-treated TNBC population Strongest clinical benefit in pts with LAR and/or Desmoplastic Stromal gene expression biomarker signatures Phase 2 Study initiated to further evaluate CB Paclitaxel combination in patients with TNBC

31 Agenda Introduction to CB-839 CB-839 combination with signal transduction inhibitors CB-839 combination with taxol in TNBC Novel combination strategies CDK4/6 and PARP inhibitors

32 Cancer vs. Normal Cell Metabolism Normal Cells GLUCOSE Cancer Cells GLUCOSE Pyruvate Lactate Pyruvate Lactate Mitochondrion Mitochondrion TCA Cycle α-kg TCA Cycle α-kg Glutamate Glutaminase Glutamate Glutaminase Intermediates for biosynthesis (e.g. nucleotides) GLUTAMINE CB-839 GLUTAMINE

33 T u m o r V o l u m e ( m m 3 ) S c a l e d I n t e n s i t y CB-839 Decreases Nucleotide Pools In Vivo CB-839 glutamine glutamate succinate fumarate TCA cycle malate oxaloacetate aspartate nucleotides glutathione a-kg citrate 1 V e h i c l e C B A M P * * 1. 5 G M P * * 2 C M P * 2 U M P * * 2 T M P * * D o s i n g S t a r t * * * * PDn V e h i c l e C B V e h i c l e C B V e h i c l e C B V e h i c l e C B V e h i c l e C B D a y s P o s t - I m p l a n t RPMI-8226 Xenograft Model

34 EdU Incorporation CB-839 Induces G1/S Cell Cycle Defect in TNBC cells CB-839 treatment causes cells to accumulate in G1 or S-phase (9 out of 11 cell lines) DMSO CB-839 H s T Hs 587T % p o p u l a t i o n G 2 / M - p h a s e S - p h a s e G 1 - p h a s e S% D M S O C B S U M P T SUM159PT % p o p u l a t i o n 1 G 2 / M - P h a s e 7 5 S - p h a s e 5 G 1 - P h a s e 2 5 D M S O C B DNA Content Cells were treated with 1 mm CB-839 for 24 hours and labelled with EdU for 2 hours 34

35 Rationale for Combining CB-839 with CDK4/6 and PARP Inhibitors CB-839 decreases in glutamate and aspartate Lower aspartate decreases the pool of nucleotides in tumors Decreased nucleotides lead to decreased rate of DNA synthesis and increased DNA damage We hypothesized that this effect by CB-839 on DNA synthesis and DNA damage may enhance the activity of CDK4/6 and PARP inhibitors 35

36 Edu Incorporation CB-839 Potentiates the Activity of CDK 4/6 Inhibitor in TNBC HCC1569 C e l l S u r v i v a l ( r e l a t i v e t o D M S O ) C B C o m b o P a l b o c i c l i b plating density Day. CB-839 (mm) CDK4/6 inh. (mm) DMSO CB-839 (1 mm) Palbo (2.5 mm) Combination DNA Content 36

37 T u m o r V o l u m e ( m m 3 ) CB-839 Enhances the Activity of CDK4/6 Inhibitor in ER + Breast Cancer M C F 7 ( E R + b r e a s t c a n c e r ) M C F - 7 X e n o g r a f t C B C o m b o C D K 4 / 6 i V e h i c l e C B P a l b o c i c l i b 6 C o m b o plating density Day 4 * * * * CB-839 (mm) Palbociclib (mm) No calculated CI values due to lack of dose response D a y s P o s t I m p l a n t 37

38 CB-839 Synergizes with PARP Inhibitor in Ovarian and Breast Cancer Cell Lines R e l a t i v e C e l l G r o w t h U W B H C C O v a r i a n C a n c e r T N B C C B C o m b o P A R P i plating density Day CB-839 (µm) PARP inh. (µm) Combination Index No calculated CI values due to lack of dose response UMB d CellTiterGlo assay PAPR inh.=niraparib HCC d CellTiterGlo assay PAPR inh.=talazoparib 38

39 Summary CB-839 is an oral, highly selective inhibitor of GLS with in vitro and in vivo anti-tumor activity Glutaminase inhibition has several downstream effects rationalizing novel combinations Signal transduction inhibitors: everolimus, cabozantinib, crizotinib, erlotinib Cell cycle inhibitors: paclitaxel and CDK4/6 inhibitors DNA repair inhibitors: PARP inhibitors Phase 1 clinical studies have shown promising clinical activity Renal cell carcinoma in combination with everolimus Triple-negative breast cancer in combination with paclitaxel

40 Acknowledgements Biology Ethan Emberley Clarissa Lee Andy MacKinnon Gisele Marguier Silinda Neou Susanne Steggerda Sandra Spurlock Pharmacology Matthew Gross Jason Chen Tony Huang Amani Makkouk Chemistry Eric Sjogren Jim Li Roland Billedeau Lijing Chen Guy Laidig Tim Stanton DMPK Weiqun Li Yong Ma Jing Zhang Winter Zhang Clinical Team Keith Orford Sam Whiting Mark Bennett Sacha Holland Yu Liang Alison Pan Pharm. Dev. Peter Shwonek Natalija Sotirovska