In the phase II RAGNAR study reported in The Lancet Oncology, Shubham Pant, MBBS, and colleagues found that the pan-FGFR tyrosine kinase inhibitor erdafitinib showed activity in patients with advanced solid tumors with FGFR alterations.

Shubham Pant, MBBS

Study Details

In the ongoing study, 217 patients aged ≥ 12 years with advanced or metastatic tumors of any histology (except urothelial cancer) with predefined FGFR1–4 alterations were enrolled from sites in 15 countries between December 2019 and February 2022. Patients must have had disease progression on at least one previous line of systemic therapy and no available alternative standard therapy.

Patients received erdafitinib at 8 mg once daily in continuous 21-day cycles until disease progression or unacceptable toxicity. The primary endpoint was objective response rate on independent review committee assessment.

Responses

At a median follow-up of 17.9 months (interquartile range = 13.6–23.9 months) at clinical cutoff in August 2022, objective responses were observed in 64 (30%, 95% confidence interval [CI] = 24%–36%) of 217 patients across 16 tumor types, with complete response observed in 3 patients. The study met its primary endpoint, rejecting the null hypothesis of an objective response rate of 15%.

The disease control rate was 74% (95% CI = 67%–80%). Median duration of response was 6.9 months (95% CI = 4.4–7.1 months); 14 patients had ongoing responses at clinical cutoff.

Responses to erdafitinib were observed in central nervous system, head and neck, thoracic, gastrointestinal, gynecologic, and thyroid cancers, and in rare malignancies such as salivary gland cancer and low-grade glioma.

Adverse Events

Grade ≥ 3 treatment-related adverse events occurred in 46% of patients, most commonly stomatitis (12%), palmar-plantar erythrodysesthesia syndrome (6%), and hyperphosphatemia (5%). Serious adverse events occurred in 39% of patients; the most common treatment-related events were stomatitis (2%) and diarrhea (1%). Central serous retinopathy of any grade occurred in 14% of patients.

The most common treatment-related adverse events leading to treatment discontinuation were palmar-plantar erythrodysesthesia syndrome and stomatitis (both occurring in 2% of patients). No treatment-related deaths were reported.

The investigators concluded, “RAGNAR results show clinical benefit for erdafitinib in the tumor-agnostic setting in patients with advanced solid tumors with susceptible FGFR alterations who have exhausted other treatment options. These results support the continued development of FGFR inhibitors in patients with advanced solid tumors.”

Dr. Pant, of the Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, and Yohann Loriot, MD, of the Department of Cancer Medicine, Gustave Roussy, Université Paris-Saclay, Villejuif, are the corresponding authors for The Lancet Oncology article.

Disclosure: The study was funded by Janssen Research & Development. For full disclosures of the study authors, visit thelancet.com.