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).

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 C 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.

Duke Scholars

Author John Strickler Medicine, Medical Oncology