Tumor agnostic efficacy and safety of erdafitinib (erda) in patients (pts) with advanced solid tumors with prespecified FGFR alterations (FGFRalt): RAGNAR primary analysis.

3121 Background: FGFRalt are present across malignancies at various frequencies and may act as oncogenic drivers across tissue histology. Erda is an oral selective pan-FGFR tyrosine kinase inhibitor with activity and safety in pts with prespecified FGFR-altered locally advanced or metastatic urothelial carcinoma (UC) and cholangiocarcinoma . RAGNAR (NCT04083976) is an ongoing phase 2 open-label, single-arm tumor agnostic trial of erda in pretreated adult and pediatric pts with FGFRalt advanced solid tumors. Interim results showed erda clinical benefit, with an objective response rate (ORR) of 29.2%. Here we report results of the primary analysis. Methods: Pts aged ≥12 y with advanced or metastatic (non-UC) tumors of any histology with predefined FGFR1-4alt (mutations/fusions per local/central test), disease progression on ≥1 prior line of systemic therapy (tx), and no alternative standard tx received oral erda until disease progression or intolerable toxicity. The primary end point was ORR by independent review committee (IRC). Secondary end points included duration of response (DOR), disease control rate (DCR [CR + PR + SD]), clinical benefit rate (CBR [CR + PR + SD >4 mo]), progression-free survival (PFS), overall survival (OS), and treatment-emergent adverse events (TEAEs). Results: At data cutoff, 217 pts were treated, median age was 57.0 y (range, 12-79), median prior systemic tx was 2 (46%; ≥3 lines of tx) with an ORR to last line prior to study entry of 10.1%. ORR to erda tx by IRC was 29.5% (95% CI, 23.5-36.0) with 6 CRs (2.8%) and 58 PRs (26.7%) in 16 distinct tumor types, including advanced CNS, thoracic, gastrointestinal, gynecologic, and rare tumors. ORR was comparable across FGFR1-3 mutations (25.3% [95% CI, 16.0-36.7]) and fusions (32.6% [95% CI, 25.1-40.9]). Median DOR, PFS, and OS were 6.9 mo (95% CI, 4.4-7.1), 4.2 mo (95% CI, 4.1-5.5), and 10.7 mo (95% CI, 8.7-12.1), respectively; DCR was 73.7% and CBR was 45.6%. 99.5% of pts experienced TEAEs, including 70.0% with grade ≥3. Treatment-related serious AEs occurred in 8.3% of pts with no treatment-related deaths. Conclusions: Primary analysis results from RAGNAR, the largest tumor agnostic trial of targeted tx to date, confirm efficacy of erda in heavily pretreated pts with FGFRalt advanced solid tumors. Erda activity was observed in adults and adolescents across tumor types, and across FGFR1-3 gene mutations and fusions. Erda tolerability was consistent with its known safety profile. Clinical trial information: NCT04083976 . [Table: see text]