Abstract # 1104 Repotrectinib Increases Effectiveness of ...
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Contact – Jim Mazzola: [email protected] INTRODUCTION • KRAS is the most frequently mutated oncogene in human cancers 1 including ~30% of non-small cell lung cancer (NSCLC), ~50% of colorectal cancer (CRC) and ~90% of pancreatic cancer 2 • Targeting downstream KRAS signaling by inhibiting MEK with trametinib showed limited activity in patients with mutant-KRAS NSCLC as a single agent or in combination with chemotherapy 3,4 • Compensatory upregulation of the PI3K/AKT survival signaling or MEK inhibitor-induced JAK/STAT3 pathway activation are reported evasion mechanisms to MEK-targeted therapies 5-7 • Repotrectinib is a compact macrocyclic inhibitor that potently inhibits SRC/ FAK/JAK2 in biochemical, cellular, and in vivo assays 8 • We previously screened 60 mutant-KRAS NSCLC, CRC, and pancreatic cell lines and found that repotrectinib in combination with trametinib resulted in a >10-fold increase in trametinib antiproliferative efficacy in 9 of 15 KRAS G12D mutant cancer models. We further evaluated repotrectinib combinations with other MAPK pathway inhibitors such as VS-6766 (MEK/RAFi) 8 • Repotrectinib is currently being evaluated in a registrational phase 2 TRIDENT-1 study 9 for patients with ROS1+ NSCLC and NTRK+ solid tumors and has been granted Breakthrough Therapy designation and 3 Fast Track designations by the FDA 10 SYNERGY ANALYSIS FOR REPOTRECTINIB COMBINATIONS WITH MEK INHIBITORS IN VITRO Figure 1. Repotrectinib Enhances Both Trametinib and VS-6766 Efficacy in A427 KRAS G12D NSCLC 0.01 0.1 1 10 100 1000 10000 0 50 100 2D Culture Concentration (nM) % Viability Trametinib Repotrectinib Repotrectinib (1 µM) + Trametinib Repotrectinib (0.5 µM) + Trametinib 0.01 0.1 1 10 100 1000 10000 0 50 100 2D Culture Concentration (nM) % Viability Repotrectinib VS-6766 Repotrectinib (1 µM) + VS-6766 Repotrectinib (0.5 µM) + VS-6766 A B 0.01 0.1 1 10 100 1000 10000 0 50 100 Spheroid Culture Spheroid Culture Concentration (nM) % Viability 0.01 0.1 1 10 100 1000 10000 0 50 100 Concentration (nM) % Viability Repotrectinib VS-6766 Repotrectinib (1 µM) + VS-6766 Repotrectinib (0.5 µM) + VS-6766 Trametinib Repotrectinib Repotrectinib (1 µM) + Trametinib Repotrectinib (0.5 µM) + Trametinib D VS-6766 (nM) Repotrectinib (nM) Bliss Synergy Score 1.5 125 11.3 4.6 125 8.6 4.6 500 6.6 1.5 500 4.9 Repotrectinib (nM) VS-6766 (nM) Bliss Synergy Plot 2000 1000 500 250 0 0 1.5 4.6 13.7 41.2 123.5 370.4 1111.1 3333.3 10000 125 C Repotrectinib (nM) Trametinib (nM) Repotrectinib (nM) Bliss Synergy Score 1.5 250 13.7 4.6 250 13.5 1.5 125 12.5 1.5 500 11.6 Trametinib (nM) Bliss Synergy Plot 2000 1000 500 250 0 0 1.5 4.6 13.7 41.2 123.5 370.4 1111.1 3333.3 10000 125 • Repotrectinib enhances inhibition of tumor cell viability by trametinib and VS-6766 in A427 KRAS G12D cancer cells grown in 2D and 3D spheroid cultures (Figures 1A and 1B) • In 3D spheroid culture, repotrectinib synergizes with trametinib to inhibit tumor cell viability (Figure 1C). In contrast, VS-6766 has an additive effect (Figure 1D) (Bliss score 0-10 = additive; Bliss score >10 = synergistic) 11 REPOTRECTINIB COMBINATIONS IN PATIENT-DERIVED KRAS MUTANT EX VIVO MODELS Figure 2. Repotrectinib Enhances Efficacy of MAPK Pathway Inhibitors in Patient-Derived KRAS G12D/V Lung and KRAS G12D/V/R Pancreatic Spheroid Models LU6419ex KRAS G12V LU5178B KRAS G12D A PA20068B KRAS G12V PA20069B KRAS G12D Drug Concentration (μM) Drug Concentration (μM) PA20074B KRAS G12R % Viability Drug Concentration (μM) % Viability C % Viability 0.0001 0.001 0.01 0.1 1 10 100 Drug Concentration (μM) 0.0001 0.001 0.01 0.1 1 10 100 Drug Concentration (μM) 0.0001 0.001 0.01 0.1 1 10 100 0 25 50 75 100 125 0.0001 0.001 0.01 0.1 1 10 100 0 25 50 75 100 125 0.0001 0.001 0.01 0.1 1 10 100 0 25 50 75 100 125 125 125 % Viability 0 25 50 75 100 % Viability 0 25 50 75 100 Repotrectinib (0.5 µM) + Trametinib VS-6766 Repotrectinib Trametinib Repotrectinib (0.5 µM) + VS-6766 Trametinib Repotrectinib (1 µM) + Trametinib VS-6766 Repotrectinib (1 µM) + VS-6766 Repotrectinib Trametinib (MEKi) Selumetinib (MEKi) LY3214996 (ERKi) VS-6766 (MEK/RAFi) TNO155 (SHP2i) Repotrectinib Trametinib (MEKi) Selumetinib (MEKi) LY3214996 (ERKi) VS-6766 (MEK/RAFi) TNO155 (SHP2i) Repotrectinib Trametinib (MEKi) Mirdametinib (MEKi) VS-6766 (MEK/RAFi) Repotrectinib Trametinib (MEKi) Mirdametinib (MEKi) VS-6766 (MEK/RAFi) Repotrectinib Trametinib (MEKi) Mirdametinib (MEKi) VS-6766 (MEK/RAFi) Repotrectinib Trametinib Repotrectinib (1 µM) + Trametinib VS-6766 Repotrectinib (1 µM) + VS-6766 Repotrectinib B 1 10 100 1000 10000 100000 LU5178B KRAS G12D IC 50 (nM) IC 50 (nM) 1 10 100 1000 10000 100000 LU6419ex KRAS G12V Single Agent Combined with Repotrectinib (1 µM) D IC 50 (nM) 1 10 100 1000 10000 1 10 100 1000 10000 1 10 100 1000 10000 PA20069B KRAS G12D IC 50 (nM) PA20068B KRAS G12V IC 50 (nM) PA20074B KRAS G12R Single Agent Combined with Repotrectinib (0.5 µM) * * * = ~1 nM. • Repotrectinib enhances inhibition of tumor cell viability by trametinib and VS-6766 in patient-derived KRAS mutant lung and pancreatic cancer models (Figures 2A and 2C, respectively) • Cell viability IC 50 values of lung and pancreatic cancer spheroids treated with MAPK pathway inhibitors as single-agent treatment or in combination with repotrectinib are shown (Figures 2B and 2D) • Repotrectinib combination with trametinib yielded superior potency compared to other MAPK pathway inhibitor combinations SIGNALING MODULATION BY REPOTRECTINIB/TRAMETINIB COMBINATION Figure 3. Repotrectinib/Trametinib Combination Suppresses Downstream Oncogenic Signaling in the A427 KRAS G12D NSCLC Cell Line pSRC Y416 SRC pSTAT3 Y705 STAT3 pFAK Y397 FAK 4h 24h Trametinib 50 nM Repotrectinib 333 nM Repotrectinib 1000 nM - - - + - - - + - + + - - - + + - + - - - + - - - + - + + - - - + + - + pERK T202/Y204 ERK pAKT S473 AKT pS6 S235/S236 S6 β-actin 4h 24h Trametinib 50 nM Repotrectinib 333 nM Repotrectinib 1000 nM - - - + - - - + - + + - - - + + - + - - - + - - - + - + + - - - + + - + B A • Repotrectinib potently inhibits SRC, FAK, and STAT3 phosphorylation (Figure 3A) • Repotrectinib/trametinib combination suppresses both ERK and AKT phosphorylation, resulting in greater inhibition of S6 phosphorylation compared to either single-agent treatment (Figure 3B) SIGNALING MODULATION BY REPOTRECTINIB/TRAMETINIB COMBINATION Figure 4. Repotrectinib/Trametinib Combination Increases Cell Cycle Arrest and Induction of Apoptosis in A427 KRAS G12D NSCLC 48h Trametinib 50 nM Repotrectinib 333 nM Repotrectinib 1000 nM PARP Cleaved PARP Cleaved caspase 3 β-actin - - - + - - - + - + + - - - + + - + 24h Trametinib 50 nM Repotrectinib 333 nM Repotrectinib 1000 nM pRB1 S807/811 RB1 p27 p21 CCNE2 β-actin - - - + - - - + - + + - - - + + - + A B 1 µm Repotrectinib + 50 nM Tram 1 µm Repotrectinib 333 nM Repotrectinib + 50 nM Tram 333 nM Repotrectinib 50 nM Trametinib Vehicle 0 5 10 % of Annexin V+ Cells 15 20 C • Repotrectinib/trametinib combination yields greater inhibition of RB1 phosphorylation, along with upregulation of p27, p21 expression, and inhibition of cyclin E2 (CCNE2) expression (Figure 4A) • Repotrectinib/trametinib combination yields greater induction of apoptosis, as evidenced by increased PARP and caspase 3 cleavage (Figure 4B) • Flow cytometry analysis of A427 cells treated with a repotrectinib/trametinib combination for 48 h showed increased levels of annexin V+ early apoptotic cells relative to single-agent treatments (Figure 4C) TRAMETINIB ACQUIRED-RESISTANCE MODELS Figure 5. Repotrectinib Can Resensitize Trametinib-Resistant Cells C Drug Concentration (nM) 0.01 1 100 10000 -25 0 25 50 75 100 %Growth PSN1 KRAS G12R 0.01 1 100 10000 -25 0 25 50 75 100 Drug Concentration (nM) %Growth A Selumetinib (Trametinib-Resist.) Trametinib (Trametinib-Resist.) Trametinib (Parental) Selumetinib (Parental) Repotrectinib (Trametinib-Resist.) Repotrectinib (Parental) Selumetinib (Trametinib-Resist.) Trametinib (Trametinib-Resist.) Trametinib (Parental) Selumetinib (Parental) Repotrectinib (Trametinib-Resist.) Repotrectinib (Parental) HCT116 KRAS G13D Drug Concentration (nM) B Trametinib (Parental) Repotrectinib (1 µM) + Trametinib (Parental) Trametinib (Trametinib-Resist.) Repotrectinib (1 µM) + Trametinib (Trametinib-Resist.) 0.01 1 100 10000 -25 0 25 50 75 100 % Growth HCT116 KRAS G13D D Drug Concentration (nM) 0.01 1 100 10000 -25 0 25 50 75 100 % Growth Trametinib (Parental) Repotrectinib (1 µM) + Trametinib (Parental) Trametinib (Trametinib-Resist.) Repotrectinib (1 µM) + Trametinib (Trametinib-Resist.) PSN1 KRAS G12R Trametinib Selumetinib Repotrectinib Trametinib-Resistant Parental PSN1 18 409 828 430 >10,000 945 GI 50 (nM) Trametinib-Resistant Parental PSN1 GI 50 (nM) Trametinib Trametinib + Repo 333 nM Trametinib + Repo 1000 nM 14 5 <1.5 489 173 <1.5 Trametinib Selumetinib Repotrectinib Trametinib-Resistant Parental HCT116 25 1058 1191 334 >10,000 1356 GI 50 (nM) Trametinib-Resistant Parental HCT116 GI 50 (nM) Trametinib Trametinib + Repo 333 nM Trametinib + Repo 1000 nM 25 12 <1.5 364 166 36 • HCT116 KRAS G13D CRC and PSN1 KRAS G12R pancreatic cancer cells were rendered resistant to trametinib via long-term step-up exposure to trametinib • Trametinib-resistant cells (HCT116 and PSN1) are >13- and >20-fold less sensitive to trametinib, respectively, compared to parental cells, and exhibit cross-resistance to selumetinib ( Figures 5A and 5C) • Trametinib-resistant cells can be resensitized to trametinib by repotrectinib (1 µM) (Figures 5B and 5D) SIGNALING MODULATION IN ACQUIRED-RESISTANCE MODELS Figure 6. Repotrectinib Resensitizes Trametinib-Resistant Cells by Repressing Compensatory AKT and S6 Activation • Repotrectinib suppresses trametinib- induced hyperphosphorylation of AKT and STAT3 in both parental and trametinib-resistant cells (Figures 6A and 6B) • Repotrectinib synergizes with trametinib, yielding greater inhibition of RB1 phosphorylation and upregulation of p27 expression in trametinib-resistant cells (Figures 6A and 6B) IN VIVO EVALUATION OF REPOTRECTINIB/TRAMETINIB COMBINATION Figure 7. Repotrectinib/Trametinib Combination Exhibits Greater Tumor Growth Inhibition in KRAS G12D Syngeneic and PDX Lung Cancer Models Vehicle BID Repotrectinib 15 mg/kg BID Trametinib 1 mg/kg QD Repotrectinib 15 mg/kg BID + Trametinib 1 mg/kg QD mLU6045 KRAS G12D 1500 1000 500 0 0 5 10 15 Days of Treatment Tumor Volume mm 3 (SEM) 20 25 **** • Repotrectinb/trametinib combination demonstrates enhanced tumor growth inhibition compared to single-agent treatment in a murine syngeneic lung cancer model harboring KRAS G12D/p53 null (MuPrime mLU6045) (**** P<0.0001) (Figure 7) and in a human LU0876 KRAS G12D lung PDX model (P<0.05; data not shown) CONCLUSIONS • Repotrectinib combinations with MEK inhibitors (trametinib, VS-6766) are more effective than single-agent treatment in patient-derived KRAS mutant lung (KRAS G12D/V) and pancreatic (KRAS G12D/V/R) spheroid models • Simultaneous inhibition of SRC/FAK/JAK2 by repotrectinib in mutant-KRAS tumor cell lines suppresses trametinib- induced AKT and STAT3 feedback activation • Repotrectinib can restore trametinib efficacy in trametinib-resistant cancer cells by suppressing AKT and JAK2/STAT3 signaling, resulting in greater inhibition of both S6 and cell cycle progression • Repotrectinib enhances trametinib efficacy in mutant KRAS G12D in vivo lung tumor models • Overall, these preclinical data suggest that combination with repotrectinib can enhance trametinib potency and may improve durability of response by reversing or preventing acquired resistance • A phase 1/2 combination study of repotrectinib and trametinib in KRAS-mutated solid tumors is currently planned HCT-116 HCT-116 Trametinib-Resistant PSN1 PSN1 Trametinib-Resistant pERK T202/Y204 ERK pFAK Y397 FAK pSTAT3 Y705 STAT3 pAKT S473 AKT pS6 S235/S236 S6 pRB1 S807/811 RB1 p27 β-actin pERK T202/Y204 ERK pFAK Y397 FAK pSTAT3 Y705 STAT3 pAKT S473 AKT pS6 S235/S236 S6 pRB1 S807/811 RB1 p27 β-actin A Veh Repo 1 uM Tram 50 nM Tram 50 + Repo Tram 150 nM Tram 150 + Repo Veh Repo 1 uM Tram 50 nM Tram 50 + Repo Tram 150 nM Tram 150 + Repo Veh Repo 1 uM Tram 50 nM Tram 50 + Repo Tram 100 nM Tram 100 + Repo Veh Repo 1 uM Tram 50 nM Tram 50 + Repo Tram 100 nM Tram 100 + Repo B References 1. Haigis KM, et al. Trends Cancer. 2017;3(10):686-97. 2. Prior IA, et al. Cancer Res. 2020;80(14):2969-74. 3. Blumenschein GR, et al. Ann Oncol. 2015;26(5):894-901. 4. Gadgeel SM, et al. J Clin Oncol. 2019;37(15):9021. 5. Lee HJ, et al. Cancer Cell. 2014;26(2):207-21. 6. Tsubaki M, et al. Cancers (Basel). 2019;11(12):1866. 7. Kun E, et al. Cancer Treat Rev. 2021;92:102137. 8. Murray B, et al. Cancer Res. 2020;80(16):Abstract 1957. 9. Clinicaltrials.gov. NCT03093116. Accessed February 17, 2021. 10. Turning Point Therapeutics granted FDA breakthrough therapy designation for repotrectinib treatment in patients with ROS1-positive metastatic non-small cell lung cancer who have not been treated with a ROS1 tyrosine kinase inhibitor [press release]. San Diego, CA: Turning Point Therapeutics, Inc.; December 8, 2020. Accessed March 8, 2021. https://ir.tptherapeutics.com/node/7601/pdf 11. Ianevski A, et al. Bioinformatics. 2017;33(15):2413-15. Acknowledgements & Disclosures This study was funded by Turning Point Therapeutics. All authors are employees of Turning Point Therapeutics. Editorial support was provided by BluPrint Oncology Concepts, LLC. Proliferation Survival Cytokines SRC FAK RTK Inhibited by Repotrectinib KRAS STAT3 JAK2 PI3K Raf Ral GEF AKT MEK NF-κB Repotrectinib Increases Effectiveness of MEK Inhibitors in KRAS KRAS Mutant Cancer Models Nathan V. Lee, Wei Deng, Dayong Zhai, Laura Rodon, Ana Parra, Jessica Cowell, Afsheen Banisadr, Xin Zhang, Brion W. Murray Turning Point Therapeutics, 10628 Science Center Drive, Suite 200, San Diego, CA 92121 Abstract # 1104 Presented at American Association for Cancer Research (AACR), April 10–15, 2021
Transcript of Abstract # 1104 Repotrectinib Increases Effectiveness of ...
Contact – Jim Mazzola: [email protected]
INTRODUCTION
• KRAS is the most frequently mutated oncogene in human cancers1 including ~30% of non-small cell lung cancer (NSCLC), ~50% of colorectal cancer (CRC) and ~90% of pancreatic cancer2
• Targeting downstream KRAS signaling by inhibiting MEK with trametinib showed limited activity in patients with mutant-KRAS NSCLC as a single agent or in combination with chemotherapy3,4
• Compensatory upregulation of the PI3K/AKT survival signaling or MEK inhibitor-induced JAK/STAT3 pathway activation are reported evasion mechanisms to MEK-targeted therapies5-7
• Repotrectinib is a compact macrocyclic inhibitor that potently inhibits SRC/FAK/JAK2 in biochemical, cellular, and in vivo assays8
• We previously screened 60 mutant-KRAS NSCLC, CRC, and pancreatic cell lines and found that repotrectinib in combination with trametinib resulted in a >10-fold increase in trametinib antiproliferative efficacy in 9 of 15 KRAS G12D mutant cancer models. We further evaluated repotrectinib combinations with other MAPK pathway inhibitors such as VS-6766 (MEK/RAFi)8
• Repotrectinib is currently being evaluated in a registrational phase 2 TRIDENT-1 study9 for patients with ROS1+ NSCLC and NTRK+ solid tumors and has been granted Breakthrough Therapy designation and 3 Fast Track designations by the FDA10
SYNERGY ANALYSIS FOR REPOTRECTINIB COMBINATIONSWITH MEK INHIBITORS IN VITRO
Figure 1. Repotrectinib Enhances Both Trametinib and VS-6766 Efficacy in A427 KRAS G12D NSCLC
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• Repotrectinib enhances inhibition of tumor cell viability by trametinib and VS-6766 in A427 KRAS G12D cancer cells grown in 2D and 3D spheroid cultures (Figures 1A and 1B)
• In 3D spheroid culture, repotrectinib synergizes with trametinib to inhibit tumor cell viability (Figure 1C). In contrast, VS-6766 has an additive effect (Figure 1D) (Bliss score 0-10 = additive; Bliss score >10 = synergistic)11
REPOTRECTINIB COMBINATIONS IN PATIENT-DERIVED KRASMUTANT EX VIVO MODELS
Figure 2. Repotrectinib Enhances Efficacy of MAPK Pathway Inhibitors in Patient-Derived KRAS G12D/V Lung and KRAS G12D/V/R Pancreatic Spheroid Models
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• Repotrectinib enhances inhibition of tumor cell viability by trametinib and VS-6766 in patient-derived KRAS mutant lung and pancreatic cancer models (Figures 2A and 2C, respectively)
• Cell viability IC50 values of lung and pancreatic cancer spheroids treated with MAPK pathway inhibitors as single-agent treatment or in combination with repotrectinib are shown (Figures 2B and 2D)
• Repotrectinib combination with trametinib yielded superior potency compared to other MAPK pathway inhibitor combinations
SIGNALING MODULATION BY REPOTRECTINIB/TRAMETINIB COMBINATION
Figure 3. Repotrectinib/Trametinib Combination Suppresses Downstream Oncogenic Signaling in the A427 KRAS G12D NSCLC Cell Line
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• Repotrectinib potently inhibits SRC, FAK, and STAT3 phosphorylation (Figure 3A)
• Repotrectinib/trametinib combination suppresses both ERK and AKT phosphorylation, resulting in greater inhibition of S6 phosphorylation compared to either single-agent treatment (Figure 3B)
SIGNALING MODULATION BY REPOTRECTINIB/TRAMETINIB COMBINATION
Figure 4. Repotrectinib/Trametinib Combination Increases Cell Cycle Arrest and Induction of Apoptosis in A427 KRAS G12D NSCLC
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• Repotrectinib/trametinib combination yields greater inhibition of RB1 phosphorylation, along with upregulation of p27, p21 expression, and inhibition of cyclin E2 (CCNE2) expression (Figure 4A)
• Repotrectinib/trametinib combination yields greater induction of apoptosis, as evidenced by increased PARP and caspase 3 cleavage (Figure 4B)
• Flow cytometry analysis of A427 cells treated with a repotrectinib/trametinib combination for 48 h showed increased levels of annexin V+ early apoptotic cells relative to single-agent treatments (Figure 4C)
TRAMETINIB ACQUIRED-RESISTANCE MODELS
Figure 5. Repotrectinib Can Resensitize Trametinib-Resistant Cells
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Trametinib (Parental)
Repotrectinib (1 µM) + Trametinib (Parental)
Trametinib (Trametinib-Resist.)
Repotrectinib (1 µM) + Trametinib (Trametinib-Resist.)
PSN1 KRAS G12R
Trametinib Selumetinib Repotrectinib
Trametinib-Resistant
Parental
PSN1
18 409 828
430 >10,000 945
GI50 (nM)
Trametinib-Resistant
Parental
PSN1GI50 (nM)
Trametinib Trametinib + Repo 333 nM Trametinib + Repo 1000 nM
14 5 <1.5
489 173 <1.5
Trametinib Selumetinib Repotrectinib
Trametinib-Resistant
Parental
HCT116
25 1058 1191
334 >10,000 1356
GI50 (nM)
Trametinib-Resistant
Parental
HCT116GI50 (nM)
Trametinib Trametinib + Repo 333 nM Trametinib + Repo 1000 nM
25 12 <1.5
364 166 36
• HCT116 KRAS G13D CRC and PSN1 KRAS G12R pancreatic cancer cells were rendered resistant to trametinib via long-term step-up exposure to trametinib
• Trametinib-resistant cells (HCT116 and PSN1) are >13- and >20-fold less sensitive to trametinib, respectively, compared to parental cells, and exhibit cross-resistance to selumetinib (Figures 5A and 5C)
• Trametinib-resistant cells can be resensitized to trametinib by repotrectinib (1 µM) (Figures 5B and 5D)
SIGNALING MODULATION IN ACQUIRED-RESISTANCE MODELS
Figure 6. Repotrectinib Resensitizes Trametinib-Resistant Cells by Repressing Compensatory AKT and S6 Activation
• Repotrectinib suppresses trametinib- induced hyperphosphorylation of AKT and STAT3 in both parental and trametinib-resistant cells (Figures 6A and 6B)
• Repotrectinib synergizes with trametinib, yielding greater inhibition of RB1 phosphorylation and upregulation of p27 expression in trametinib-resistant cells (Figures 6A and 6B)
IN VIVO EVALUATION OF REPOTRECTINIB/TRAMETINIB COMBINATION
Figure 7. Repotrectinib/Trametinib Combination Exhibits Greater Tumor Growth Inhibition in KRAS G12D Syngeneic and PDX Lung Cancer Models
Vehicle BID
Repotrectinib 15 mg/kg BID
Trametinib 1 mg/kg QD
Repotrectinib 15 mg/kg BID+ Trametinib 1 mg/kg QD
mLU6045 KRAS G12D1500
1000
500
00 5 10 15
Days of Treatment
Tum
or V
olum
e m
m3 (
SEM
)
20 25
****
• Repotrectinb/trametinib combination demonstrates enhanced tumor growth inhibition compared to single-agent treatment in a murine syngeneic lung cancer model harboring KRAS G12D/p53 null (MuPrime mLU6045) (**** P<0.0001) (Figure 7) and in a human LU0876 KRAS G12D lung PDX model (P<0.05; data not shown)
CONCLUSIONS
• Repotrectinib combinations with MEK inhibitors (trametinib, VS-6766) are more effective than single-agent treatment in patient-derived KRAS mutant lung (KRAS G12D/V) and pancreatic (KRAS G12D/V/R) spheroid models
• Simultaneous inhibition of SRC/FAK/JAK2 by repotrectinib in mutant-KRAS tumor cell lines suppresses trametinib-induced AKT and STAT3 feedback activation
• Repotrectinib can restore trametinib efficacy in trametinib-resistant cancer cells by suppressing AKT and JAK2/STAT3 signaling, resulting in greater inhibition of both S6 and cell cycle progression
• Repotrectinib enhances trametinib efficacy in mutant KRAS G12D in vivo lung tumor models
• Overall, these preclinical data suggest that combination with repotrectinib can enhance trametinib potency and may improve durability of response by reversing or preventing acquired resistance
• A phase 1/2 combination study of repotrectinib and trametinib in KRAS-mutated solid tumors is currently planned
HCT-116HCT-116
Trametinib-Resistant PSN1PSN1
Trametinib-Resistant
pERKT202/Y204
ERKpFAKY397
FAKpSTAT3Y705
STAT3pAKTS473
AKTpS6S235/S236
S6pRB1S807/811
RB1p27
β-actin
pERKT202/Y204
ERKpFAKY397
FAKpSTAT3Y705
STAT3pAKTS473
AKTpS6S235/S236
S6pRB1S807/811
RB1p27
β-actin
A
Veh
Repo 1 uM
Tram 50 nM
Tram 50 + R
epo
Tram 150 nM
Tram 150 + R
epo
Veh
Repo 1 uM
Tram 50 nM
Tram 50 + R
epo
Tram 150 nM
Tram 150 + R
epo
Veh
Repo 1 uM
Tram 50 nM
Tram 50 + R
epo
Tram 100 nM
Tram 100 + R
epo
Veh
Repo 1 uM
Tram 50 nM
Tram 50 + R
epo
Tram 100 nM
Tram 100 + R
epo
B
References1. Haigis KM, et al. Trends Cancer. 2017;3(10):686-97.2. Prior IA, et al. Cancer Res. 2020;80(14):2969-74.3. Blumenschein GR, et al. Ann Oncol. 2015;26(5):894-901.4. Gadgeel SM, et al. J Clin Oncol. 2019;37(15):9021. 5. Lee HJ, et al. Cancer Cell. 2014;26(2):207-21. 6. Tsubaki M, et al. Cancers (Basel). 2019;11(12):1866.7. Kun E, et al. Cancer Treat Rev. 2021;92:102137.
8. Murray B, et al. Cancer Res. 2020;80(16):Abstract 1957.9. Clinicaltrials.gov. NCT03093116. Accessed February 17, 2021.10. Turning Point Therapeutics granted FDA breakthrough therapy designation for
repotrectinib treatment in patients with ROS1-positive metastatic non-small cell lung cancer who have not been treated with a ROS1 tyrosine kinase inhibitor [press release]. San Diego, CA: Turning Point Therapeutics, Inc.; December 8, 2020. Accessed March 8, 2021. https://ir.tptherapeutics.com/node/7601/pdf
11. Ianevski A, et al. Bioinformatics. 2017;33(15):2413-15.
Acknowledgements & Disclosures This study was funded by Turning Point Therapeutics. All authors are employees of Turning Point Therapeutics.
Editorial support was provided by BluPrint Oncology Concepts, LLC.
ProliferationSurvival Cytokines
SRCFAK RTK
Inhibited by Repotrectinib
KRAS
STAT3
JAK2
PI3K Raf Ral GEF
AKT MEK NF-κB
Repotrectinib Increases Effectiveness of MEK Inhibitors in KRASKRAS Mutant Cancer ModelsNathan V. Lee, Wei Deng, Dayong Zhai, Laura Rodon, Ana Parra, Jessica Cowell, Afsheen Banisadr, Xin Zhang, Brion W. Murray
Turning Point Therapeutics, 10628 Science Center Drive, Suite 200, San Diego, CA 92121
Abstract # 1104
Presented at American Association for Cancer Research (AACR), April 10–15, 2021
