Phase 1/1b trial of fruquintinib in patients with advanced solid tumors: Preliminary results of the dose expansion cohorts in refractory metastatic colorectal cancer.

Abstract

93 Background: Fruquintinib (F) is a highly selective, novel, oral tyrosine kinase inhibitor (TKI) of vascular endothelial growth factor receptors (VEGFR) -1, -2, and -3. The phase (Ph) 3 FRESCO study (NCT02314819) that investigated F (5mg daily, 3 weeks (wks) on 1 wk off) showed improved median overall survival in patients (pts) with metastatic colorectal cancer (mCRC) in third line and beyond when compared to placebo (9.3 vs. 6.6 months); hazard ratio 0.65 (P < 0.001) and led to its approval in China. Methods: This is an ongoing Ph 1/1b open-label, dose escalation/expansion study conducted in the US. Here we present the preliminary safety and antitumor efficacy data from pts with refractory mCRC in Cohort (Coh) B (progressed on all standard therapies including TAS-102 [TAS] and/or regorafenib [R]) and in Coh C (did not receive TAS or R). Results: As of data cutoff on 27 July 2021, 81 mCRC pts had been treated (41 in Coh B and 40 in Coh C); median age of 57 years (range: 34─77), Caucasian (81.5%), female (44.4%), and ECOG PS 1 (59.3%). In Coh B, the median number of prior therapies was 5 (range: 3-9), 8 pts (19.5%) received R, 19 (46.3%) received TAS and 14 (34.1%) received both R and TAS. In Coh C, the median number of prior therapies was 4 (range: 1-10). Five pts remain on treatment; reasons for treatment discontinuation included: 56 pts (69.1%) due to progressive disease or death, 8 pts (9.9%) due to adverse events (AE), and 12 pts (14.8%) due to withdrawal of consent or physician decision. The median duration of F treatment was 4.4 months (range: 0.7– 20.0) in Coh B and 3.7 months (range: 0.02-14.3) in Coh C. The most frequently reported AEs of any grade in Coh B were fatigue (53.7%), proteinuria (51.2%), and hypertension (HTN; 48.8%). In Coh C the most frequently reported AEs of any grade were HTN (75.0%), proteinuria (40.0%), and myalgia (32.5%). Hand-foot syndrome (HFS) was reported in 29.3% of Coh B pts and 22.5% of Coh C pts. The disease control rate [DCR] was 68.3% in Coh B (1 partial response [PR] and 27 stable disease [SD]) and 59.5% for the 37 patients with at least one post-baseline tumor assessment in Coh C (2 PRs and 20 SDs). Conclusions: F is generally well-tolerated in heavily-pretreated pts with refractory mCRC. Evidence of antitumor activity was observed in cohorts B and C. The multi-cohort dose expansion is ongoing. F is being further investigated in refractory mCRC in a global Ph 3 study (NCT04322539). Clinical trial information: NCT03251378.