Safety and activity of the pan-fibroblast growth factor receptor (FGFR) inhibitor erdafitinib in phase 1 study patients (Pts) with molecularly selected advanced cholangiocarcinoma (CCA).

Abstract

4074 Background: Erdafitinib (JNJ-42756493) is a potent, oral pan-FGFR tyrosine kinase inhibitor that demonstrated encouraging preliminary clinical activity and manageable adverse events (AEs) in its first-in-human phase 1 study in advanced solid tumors (NCT01703481). Here we report results from pts with CCA from this study. Methods: This 4-part study enrolled pts age ≥ 18 years (y) with advanced solid tumors. Dose escalation (part 1) followed a 3+3 design, with pts receiving ascending doses of erdafitinib continuously or intermittently (7 days on/7 days off). Subsequent parts required FGFR gene alterations in the tumor, including activating mutations and translocations or other FGFR-activating aberrations. Part 2 was a pharmacodynamics cohort. Parts 3 and 4 were dose-expansion cohorts for recommended phase 2 doses of 9 mg once daily (QD) and 10 mg intermittently, respectively. Results: Eleven pts with FGFR-aberrant CCA were treated at 9 mg QD (n = 1) or 10 mg intermittent (n = 10). Median age was 60 y; 7 of 11 pts were female (64%). 73% of pts had ECOG performance status 1. All had prior systemic therapy. Median treatment duration with erdafitinib was 5.3 months (mo). Systemic erdafitinib exposure, per Cmax and AUC, in CCA pts was similar to other indications. The most common AEs were stomatitis (82%), hyperphosphatemia (64%), dry mouth (55%), dysgeusia (45%), dry skin (45%), and asthenia (45%), mostly grade 1/2 severity. No drug-related grade ≥3 AEs were reported in > 1 pt except grade 3 stomatitis (n = 2; 18%). The objective response rate, all confirmed partial responses (PRs) per RECIST 1.1, was 27.3% (3/11; 95% CI 6, 61); an additional 27.3% (3/11) had stable disease as their best response. Overall disease control rate was 55%. All 3 PRs were at the 10 mg intermittent dosage, and the median duration of response was 12.9 mo. With a median follow-up of 5.1 mo, median progression-free survival was 5.1 mo (95% CI 1.6, 16.4). As of the cutoff date, 2 pts continue on study treatment. Conclusions: Erdafitinib showed encouraging clinical activity and minimal toxicity in pts with advanced CCA and FGFR alterations. These results warrant further study. Clinical trial information: NCT01703481.