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Supplementary Tables 1-4, Figures 1-4 from Peloruside- and Laulimalide-Resistant Human Ovarian Carcinoma Cells Have βI-Tubulin Mutations and Altered Expression of βII- and βIII-Tubulin Isotypes

Supplementary Figure Legends from The Synergistic Combination of the Farnesyl Transferase Inhibitor Lonafarnib and Paclitaxel Enhances Tubulin Acetylation and Requires a Functional Tubulin Deacetylase

Supplementary Figure 2 from The Synergistic Combination of the Farnesyl Transferase Inhibitor Lonafarnib and Paclitaxel Enhances Tubulin Acetylation and Requires a Functional Tubulin Deacetylase

Supplementary Table 1 from The Synergistic Combination of the Farnesyl Transferase Inhibitor Lonafarnib and Paclitaxel Enhances Tubulin Acetylation and Requires a Functional Tubulin Deacetylase

Farnesyl transferase (FT) inhibitors (FTI) are anticancer agents developed to target oncogenic Ras proteins by inhibiting Ras farnesylation. FTIs potently synergize with paclitaxel and other microtubule-stabilizing drugs; however, the mechanistic basis underlying this synergistic interaction remains elusive. Here we show that the FTI lonafarnib affects the microtubule cytoskeleton resulting in microtubule bundle formation, increased microtubule stabilization and acetylation, and suppression of microtubule dynamics. Notably, treatment with the combination of low doses of lonafarnib with paclitaxel markedly enhanced tubulin acetylation (a marker of microtubule stability) as compared with either drug alone. This synergistic effect correlated with FT inhibition and was accompanied by a synergistic increase in mitotic arrest and cell death. Mechanistically, we show that the combination of lonafarnib and paclitaxel inhibits the in vitro deacetylating activity of the only known tubulin deacetylase, histone deacetylase 6 (HDAC6). In addition, the lonafarnib/taxane combination is synergistic only in cells lines expressing the wild-type HDAC6, but not a catalytic-mutant HDAC6, revealing that functional HDAC6 is required for the synergy of lonafarnib with taxanes. Furthermore, tubacin, a specific HDAC6 inhibitor, synergistically enhanced tubulin acetylation in combination with paclitaxel, similar to the combination of lonafarnib and paclitaxel. Taken together, these data suggest a relationship between FT inhibition, HDAC6 function, and cell death, providing insight into the putative molecular basis of the lonafarnib/taxane synergistic antiproliferative combination.

Supplementary Figure 1 from The Synergistic Combination of the Farnesyl Transferase Inhibitor Lonafarnib and Paclitaxel Enhances Tubulin Acetylation and Requires a Functional Tubulin Deacetylase

BACKGROUND Brain metastases (BMs) occur in 20–40% of patients with METex14 skipping NSCLC. Tepotinib, a highly selective MET inhibitor, demonstrated an objective response rate (ORR) of 49.1% and median duration of response (mDOR) of 13.8 months, in METex14 skipping NSCLC patients in the Phase II VISION study (Cohorts A+C; N=275). Here, we report the intracranial activity of tepotinib in VISION. METHODS Patients with METex14 skipping NSCLC received oral tepotinib 500 mg QD (450 mg active moiety). Patients with BM (asymptomatic and symptomatic/stable) were eligible. Primary endpoint was systemic ORR (RECIST v1.1); a subgroup analysis in patients with BM was predefined (data cut-off: February 1, 2021). An ad-hoc retrospective analysis of brain lesions was conducted by an IRC using RANO-BM criteria. Responses were determined in patients with ≥1 evaluable post-baseline tumor assessment. For those with only non-target lesions (NTLs) per RANO-BM (enhancing and non-enhancing NTLs), disease control was defined as non-complete response (CR)/nonprogressive disease (PD). Data cut-off: July 1, 2020. RESULTS Fifty-one patients had baseline BM (Cohorts A+C). Systemic efficacy was consistent with the overall population (ORR 52.9% [95% CI: 38.5, 67.1], mDOR 9.0 months [95% CI: 5.6, not estimable]). Fifteen patients were evaluable by RANO-BM (Cohort A); 12 received prior radiotherapy for BM (median 6.4 weeks before treatment). Systemic best objective responses (BORs) were partial response (PR, n=9), stable disease (SD, n=3), and PD (n=3). Seven patients had target CNS lesions per RANO-BM (all with prior radiotherapy); intracranial BORs were PR (n=5), SD (n=1), and PD (n=1). For patients with NTL only (n=8), one had PD, and seven achieved intracranial disease control with three patients achieving CR of the enhancing NTL. 13/15 patients achieved intracranial disease control. CONCLUSIONS Tepotinib demonstrated robust systemic activity in patients with METex14 skipping NSCLC with BM, complemented by intracranial activity in an ad-hoc analysis using RANO-BM.

Background Brain metastases (BMs) are reported in 20–40% patients with METex14 skipping NSCLC. Tepotinib, a highly selective MET inhibitor, has demonstrated an objective response rate (ORR) of 45% and median duration of response (mDOR) of 11.1 months, in METex14 skipping NSCLC patients in Cohort A of the Phase II VISION study. Here, we report the intracranial activity of tepotinib in Cohort A. Methods Patients received oral tepotinib 500 mg QD. Study eligibility allowed for patients with BM (asymptomatic and symptomatic/stable). Primary endpoint: systemic objective response (RECIST v1.1); subgroup analysis in patients with BM (RECIST v1.1) was predefined. An ad hoc retrospective analysis of brain lesions (by CT/MRI) was conducted by an IRC using Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) criteria. Responses were determined in patients with ≥1 evaluable post-baseline tumor assessment. For non-measurable lesions (enhancing and non-enhancing non-target lesions [NTL]), disease control in the brain was defined as non-complete response/non-progressive disease. Data cut-off: July 1, 2020. Results Twenty-three patients had baseline BM. Systemic efficacy in patients with BM (ORR 47.8% [95% CI: 26.8, 69.4]; mDOR 9.5 months [95% CI: 5.5, not estimable]) was consistent with the overall population. Fifteen patients were evaluable by RANO-BM; 12 received prior radiotherapy for BM (median 6.4 weeks before treatment). Systemic best objective responses (BORs) were partial response (PR, n=9), stable disease (SD, n=3), and progressive disease (PD; n=3). Of seven patients with measurable CNS disease (all of whom received prior radiotherapy), intracranial BORs were PR (n=5), SD (n=1), and PD (n=1). For patients with NTL only (n=8), one had PD, and seven achieved intracranial disease control with three patients achieving CR of the enhancing NTL. Conclusions Tepotinib demonstrated intracranial activity in patients with METex14 skipping NSCLC with BM. Prospective evaluation of intracranial activity in VISION Cohort C is ongoing.

9084 Background: Brain metastases (BMs) are reported in 20–40% of pts with METex14 skipping NSCLC and present a high unmet need with poor prognosis. Tepotinib is a highly selective MET inhibitor that has demonstrated intracranial activity in preclinical MET-driven lung cancer orthotopic BM models, and has high binding in brain tissue with 25% of free tepotinib levels in brain, relative to plasma. In VISION Cohort A (N = 152), tepotinib had robust and durable clinical activity in pts with METex14 skipping NSCLC, with an objective response rate (ORR) of 45% and a median duration of response (mDOR) of 11.1 months. Here, we report the intracranial activity of tepotinib. Methods: In the Phase II VISION study, pts with METex14 skipping NSCLC received 500 mg QD (450 mg active moiety) oral tepotinib. Study eligibility allowed for pts with BM (neurologically stable on symptomatic therapy with stable steroids, and pts with asymptomatic BM). Primary endpoint: systemic OR per RECIST v1.1; subgroup analysis in pts with BM (determined by RECIST v1.1) was predefined. An ad hoc retrospective analysis of brain lesions determined by CT/MRI was conducted by an IRC using Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) criteria, which accounts for pts’ clinical status and steroid use. Responses were determined in pts with ≥1 evaluable post-baseline tumor assessment (due to the retrospective nature and resulting incomplete data, confirmation was not required). For pts with non-measurable lesions per RANO-BM (enhancing and non-enhancing non-target lesions [NTL]), disease control in the brain was defined as non-complete response/non-progressive disease. Data cut-off: July 1, 2020. Results: Based on RECIST v1.1, 23 pts in Cohort A had BM at baseline. Systemic efficacy in pts with BM (ORR 47.8% [95% CI: 26.8, 69.4], mDOR 9.5 months [95% CI: 5.5, not estimable]) was consistent with the overall population. 15 pts were evaluable by RANO-BM; 12 received prior radiotherapy for BM (median 6.4 weeks before tepotinib initiation [range 2.6–44]). Systemic best objective responses (BORs) were partial response (PR, n = 9), stable disease (SD, n = 3), and progressive disease (PD; n = 3). Of 7 pts with measurable CNS disease per RANO-BM (all of whom received prior radiotherapy), intracranial BORs were PR (n = 5; including 3 with complete disappearance of target lesions), SD (n = 1) and PD (n = 1). Of 8 pts with NTL only, 7 achieved intracranial disease control and 1 had PD. Of the 7 pts with disease control, 3 had CR of the enhancing NTL. Conclusions: Tepotinib demonstrated robust systemic activity in pts with METex14 skipping NSCLC with BM; this is complemented by intracranial activity in an ad hoc analysis using RANO-BM. Small pt numbers, a large proportion of pts with prior radiotherapy for BM, and the retrospective nature of analysis should be considered. Prospective evaluation of intracranial activity data from VISION Cohort C is ongoing. Clinical trial information: NCT02864992.

329 Background: Tepotinib, a potent and highly selective MET inhibitor, showed promising activity in advanced HCC with MET overexpression in two Phase Ib/II trials, which both met their primary endpoints. One trial enrolled Asian patients (pts) without prior systemic therapy (first line [1L]; NCT01988493) and one enrolled US/European pts with prior sorafenib (second line [2L]; NCT02115373). By investigator assessment, objective response rates and disease control rates with tepotinib in Phase II were 15.8% and 60.5% in 1L (n = 38), and 8.2% and 57.1% in 2L (n = 49). Outcomes appeared better in pts with METamp. Thus, we further investigated the preclinical and clinical activity of tepotinib in HCC, focusing on high-level METamp, which could be an oncogenic driver in this tumor type. Methods: Preclinical activity was assessed in 37 HCC pt-derived xenografts (PDXs) in nude mice treated with tepotinib (100 mg/kg, Days 1–5, every 7 days for five cycles; 6–12 replicates per PDX). Clinical activity was assessed by analyzing pts with METamp or high-level METamp (defined as mean MET gene copy number [GCN] ≥5 and ≥10, respectively; by fluorescence in situ hybridization), who received tepotinib 500 mg in Phase Ib or II of the 1L and 2L trials (n = 121). In the Phase Ib part of the 1L trial, pts could have received prior treatment. Results: Molecular profiling revealed high-level METamp in two of 37 HCC PDXs: LIM612 ( MET GCN 47.1) and LIPF210 ( MET GCN 44). Tepotinib induced significant tumor regression in both of these high-level METamp HCC PDX models (mean tumor volume reduction: 97% and 96%, respectively). Across the two trials, 15 pts treated with tepotinib 500 mg had METamp, of whom five had an objective response (one complete response [CR] and four partial responses [PRs]) and six had stable disease (SD) as best overall response. Four pts had high-level METamp (mean MET GCN 14.3, 18.1, 30.2, and 36.2), with best overall response of CR in one pt, PR in two pts and SD in one pt (Table). One pt with high-level METamp (mean MET GCN 14.3) treated with 1L tepotinib was still receiving treatment as of Sept 2020 (total tepotinib treatment duration: > 45 months). Conclusions: High-level METamp may be an oncogenic driver in HCC that sensitizes tumors to MET inhibition with tepotinib. Compared with MET overexpression, high-level METamp could be a better predictive biomarker for MET inhibitors in this setting. Clinical trial information: NCT01988493, NCT02115373. [Table: see text]