Wu, Frank

608 Background: Tinengotinib, a spectrum-selective multi-kinase inhibitor with unique binding properties to FGFR , potently inhibited FGFR2 fusion/rearrangement and acquired resistant/gatekeeper mutations in pre-clinical models and exhibited antitumor activity in cholangiocarcinoma (CCA) patients (pts) in phase 1/2 trials. Here we present the overall survival (OS) data and biomarker correlative analysis from a phase 2 clinical trial of tinengotinib in CCA. Methods: Eligible pts with advanced/metastatic CCA who had received ≥ 1 prior systemic chemotherapy with ECOG PS 0-1 were treated with tinengotinib 10 mg QD across four Cohorts: A1: FGFR2 fusion(s) with primary progression on previous FGFR inhibitor ( FGFR i); A2: FGFR2 fusion(s) with progression after prior response to FGFR i; B: FGFR alteration(s) without FGFR2 fusion(s); C: FGFR wild-type. Efficacy was evaluated per RECIST v1.1 and safety was assessed by CTCAE v5.0. Genomic alterations in circulating tumor DNA (ctDNA) were assessed by Foundation Medicine NGS panel at baseline, C3D1 and EOT. Planned correlative analyses of response (PR+SD>6 months) and PFS in pt subgroups based on ctDNA mutational status were performed. Results: 55 eligible pts were enrolled (18 in A1, 11 in A2, 13 in B, 13 in C) with median age 61.0 [range 24-81] years, ECOG PS 0 in 50.9% pts, 56.4% female, and 60.0% with ≥ 3 lines of prior therapy. Among 42 pts with FGFR alterations, 78.4% had ≥ 1 prior FGFR i, and 97.6% had prior chemotherapy. Median follow up time was 8.6 months (0.4-30.5). The median OS (months) was 17.1 (95%CI 7.5-19.5) in A1; not reached (95%CI 9.6, -) in A2; 18.0 (95%CI 9.6, -) in A1+A2; not reached (95%CI 8.0, -) in B; 6.5 (95%CI 4.8-16.4) in C. The OS rate in A, B and C was 100%, 91.7% and 75% at month 3; 83.7%, 83.3% and 66.7% at month 6, and 65.8%, 55.6% and 23.8% at month 12. Partial response was observed in 26% (10/39) of evaluable FGFR-altered pts (A1+A2+B). The safety profile was consistent with previous reports. The most common any-grade treatment-related AEs were hypertension (63.6%) and diarrhea (47.3%). Baseline ctDNA results were available in 46 pts, 35 in cohorts A+B and 11 in C. A positive correlation was shown in MED12 mutation vs response (P=0.03476). BCOR and ARID1A mutation were found to be negatively associated with PFS (P=0.01366 and P=0.0437). Acquired/secondary mutations at baseline were observed in cohort A, including V564F/I (3/24 and 5/24) and N549K/H (5/24 and 5/24); favorable anti-tumor activity was noted despite these resistant mutations, consistent with preclinical data. Conclusions: Tinengotinib has shown promising anti-tumor efficacy in CCA pts with FGFR fusion after prior FGFR i and in those with primary FGFR mutations. An ongoing randomized phase III study will investigate tinengotinib vs. chemotherapy in FGFR inhibitor refractory CCA (NCT05948475). Clinical trial information: NCT04919642 .

Abstract Background: Fibroblast growth factor receptor (FGFR) alterations occur across various malignancies and are potent oncogenic drivers in multiple tumor types. FGFR inhibitors have demonstrated efficacy in several cancers with FGFR alterations. Tinengotinib is a novel kinase inhibitor with high potency to a variety of FGFR 1/2/3 kinase domain mutations and has shown promising efficacy in several ongoing clinical studies. Here, we present pooled data of tinengotinib in previously treated solid tumor patients (pts) with actionable FGFR1-3 mutations from four trials (NCT03654547, NCT04742959, NCT04919642, NCT05253053). Methods: Eligible pts received tinengotinib orally once daily (daily dose ranging from 5-12mg) until disease progression. Analyses of best overall response (BOR) rate, disease control rate (DCR), median progression-free survival (mPFS), median duration of response (mDOR) and treatment-related adverse events (TRAEs) were performed. Results: As of 3-Aug-2023, 53 solid tumor pts with actionable FGFR1-3 mutations were enrolled between Dec-2019 to Aug-2023 in the US and China. The median follow-up time was 14.5 (range, 3.3-43.8) months. Median age was 58 years (range, 29-83). Most pts were female (62%), had ECOG of 1 (68%) and were heavily pretreated with 55% having ≥3 lines of prior antitumor therapy. The most frequent FGFR mutation enrolled was in FGFR2 (77%) followed by FGFR1 (19%) and FGFR3 (11%). 25 pts (47%) had received prior therapy with FGFR inhibitor. A total of 45 pts were efficacy-evaluable, including cholangiocarcinoma (CCA, n=25), colon cancer (n=5), breast cancer (n=3), prostate cancer (n=3), head and neck cancer (n=3), urothelial cancer (n=3), pancreatic cancer (n=1), gastric cancer (n=1) and leiomyosarcoma (n=1). mPFS reached 6.83 (95% CI, 4.90-8.34) months. Partial responses were observed in 16/45 (35.6%) pts across 6 distinct tumor types, including CCA, breast, prostate, urothelium, colon and head and neck cancer. mDOR was 6.74 (95% CI, 3.52-9.46) months. For 44 pts with measurable target lesions per RECISTv1.1, the BOR rate and DCR were 36.4% and 86.4%, respectively. For 22 pts with prior FGFR inhibitor, mPFS was 5.98 (95% CI, 3.75-9.10) months and their BOR rate and DCR were 40.9% and 86.4%. TRAEs were reported in 46 (86.8%) pts, with 13 (24.5%) Grade (G) 1-2, 30 (56.6%) G3, 2 (3.8%) G4, and no G5. The most common TRAEs (≥20%) were hypertension, stomatitis, diarrhea, nausea, blood thyroid stimulating hormone increased, fatigue and anemia. Side effects were manageable and reversible with dose hold and/or dose reduction. Conclusions: We observed promising clinical benefit with tinengotinib in heavily pretreated solid tumor pts with FGFR1-3 mutations. The side effects profile was manageable and no new safety signals have been identified. Further research is planned to evaluate the safety and efficacy of tinengotinib in pts with FGFR1-3 mutations across a wider variety of tumor types. Citation Format: Sarina A. Piha-Paul, Chih-Yi "Andy" Liao, Lionel Fonkoua, Amit MahipaI, Sanjay Goel, Christos Fountzilas, Lin Shen, Daneng Li, Dustin Deming, Farshid Dayyani, Weiqing Han, Zuoxing Niu, Jean Fan, Peng Peng, Hui Wang, Peng Huang, Frank Wu, Milind Javle. Tinengotinib in patients with advanced solid tumors harboring actionable FGFR1-3 mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB162.

434 Background: Tinengotinib is a spectrum-selective multi-kinase inhibitor with unique binding properties to FGFR, potently inhibited FGFR2 fusion/rearrangement and acquired resistant mutations in pre-clinical models and in phase I trials that included cholangiocarcinoma (CCA) patients (pts). Here we present the efficacy and safety of tinengotinib in a phase II clinical trial. Methods: Eligible pts with advanced/metastatic CCA who had received ≥ 1 prior systemic chemotherapy therapy and ECOG PS 0 or 1 were treated with tinengotinib 10 mg QD. Four cohorts included: Cohort A1: FGFR2 fusion(s) with primary progression on previous FGFR inhibitor ( FGFRi), A2: FGFR2 fusion(s) with progression after prior response to FGFRi (acquired resistance); B: non-fusion FGFR alteration(s): C: FGFR wild-type ( FGFRwt). Primary endpoint was objective response rate (ORR) per RECIST v1.1. CTCAE V5.0 was used for safety assessments. Results: As of 7Aug2023, 48 pts with CCA were enrolled, 13 in Cohort A1, 10 in A2, 12 in B, 13 in C. Median age 61.5 [range 25-81] years old, 41.7% male, 58.3% had ≥ 3 lines of prior therapy. ECOG PS 0 in 47.9% pts. Among 35 pts with FGFR alterations, 80.0% had ≥ 1 prior FGFRi therapy, and 97.1% had prior chemotherapy. Forty (40) pts were efficacy evaluable. In A1, 1 out of 11 pts (9.1%) achieved PR with tumor reduction of 31.8%. In A2, 3 out of 8 pts (37.5%) achieved PR with tumor reduction of 40.7%, 47.0% and 54.6%. In B, 3 out of 9 pts (33.3%) achieved PR with tumor reduction of 36.5%, 48.6%, and 60.6%. No PR was observed in C. Overall DCR was 94.7% (18/19) in FGFR2 fusion/rearrangement pts (A1+A2), 88.9% (8/9) in other FGFR alterations pts (B), and 75% (9/12) in FGFRwt pts (C). Median progression-free survival (mPFS) was 5.26 months (95%CI, 2.86-9.10) in A1+A2, 5.98 months (95%CI, 1.87-NA) in B and 3.84 months (95% CI, 1.84-4.80) in C. Among 48 treated pts, treatment-related AEs (TRAEs) occurred in 45 (93.8%) pts, 14 (29.2%) in G1-2, 29 (60.4%) in G3 and 2 (4.2%) in G4. The most common G3 TRAEs were hypertension in 12 (25%), palmar-plantar erythrodysesthesia syndrome in 3 (6.3%), diarrhea in 3 (6.3%) and stomatitis in 3 (6.3%). One subject had G4 increased TSH and G4 increased lipase, and another subject had G4 posterior reversible encephalopathy syndrome. No G5 TRAE was observed. Conclusions: Tinengotinib has promising clinical benefit for FGFR2 fusion CCA after prior FGFRi and for non-fusion FGFR alterations. Tinengotinib-related toxicities were manageable. An ongoing randomized, controlled phase III study will evaluate the clinical efficacy, safety, and pharmacodynamic effect of Tinengotinib vs Physicians’ choice in subjects with FGFR2-altered refractory/relapsed CCA after prior chemotherapy and FGFRi therapy. Clinical trial information: NCT04919642 .