First Targeted Therapy for Metastatic Bladder Cancer Receives FDA Approval

Official with the FDA today granted accelerated approval to erdafitinib (Balversa, Janssen) for adult patients with locally advanced or metastatic bladder cancer. This treatment is used for treating the indicated cancer that has a type of susceptible genetic alteration­­, FGFR3 or FGFR2, and that has progressed during or following prior platinum-containing chemotherapy.

Erdafitinib was granted a Breakthrough Therapy designation, and it received Accelerated Approval from the FDA. The Accelerated Approval designation enables the agency to focus on drugs for serious conditions that fill an unmet medical need, using clinical trial data that is thought to predict a clinical benefit to patients. Further clinical trials are required to confirm the drug’s clinical benefit.

The FDA also approved the therascreen FGFR RGQ RT-PCR Kit (Qiagen) for use as a companion diagnostic with erdafitinib for this therapeutic indication. According to the agency, patients should be selected for therapy with erdafitinib using this device.

“We’re in an era of more personalized or precision medicine, and the ability to target cancer treatment to a patient’s specific genetic mutation or biomarker is becoming the standard, with advances being made in new disease types. Today’s approval represents the first personalized treatment targeting susceptible FGFR genetic alterations for patients with metastatic bladder cancer,” said Richard Pazdur, MD, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, in a prepared statement. “FGFRs regulate important biological processes including cell growth and division during development and tissue repair. This drug works by targeting genetic alterations in FGFRs.”

The most common type of bladder cancer is transitional cell carcinoma, also called urothelial carcinoma. Bladder cancers are associated with genetic mutations that are present in the patient's bladder or entire the lining of the lower urinary tract. Bladder cancer is the sixth most common cancer in the United States. Fibroblast growth factor (FGFR) alterations are present in approximately 1 in 5 patients with recurrent and refractory bladder cancer.

The efficacy of erdafitinib was studied in a clinical trial that included 87 patients with locally advanced or metastatic bladder cancer, with FGFR3 or FGFR2 genetic alterations, that had progressed following treatment with chemotherapy. The overall response rate in these patients was 32.2%, with 2.3% having a complete response and nearly 30% having a partial response. The response lasted for an average of approximately 5.5 months.

About a quarter of patients in the study were previously treated with anti PD-L1/PD-1 therapy, which is a standard treatment for patients with locally advanced or metastatic bladder cancer. Responses to erdafitinib were seen in patients who had previously not responded to anti PD-L1/PD-1 therapy.

Common adverse effects reported by patients taking erdafitinib were increased phosphate level, mouth sores, feeling tired, change in kidney function, diarrhea, dry mouth, nails separating from the bed or poor formation of the nail, change in liver function, low sodium levels, decreased appetite, change in sense of taste, anemia, dry skin, dry eyes and hair loss. Other adverse effects include redness, swelling, peeling or tenderness on the hands or feet, constipation, stomach pain, nausea and muscle pain.

In addition, erdafitinib may cause serious eye problems, including inflamed eyes, inflamed cornea, and disorders of the retina. According to the FDA, patients are advised to have eye examinations intermittently and to tell their health care professional right away if they develop blurred vision, loss of vision or other visual changes. Health care professionals are advised to check patients’ blood phosphate level between 14 and 21 days after starting treatment and monthly, and to increase the dose erdafitinib in patients whose serum phosphate is below the target level.

Health care professionals also are advised to tell male patients with female partners of reproductive potential to use effective contraception during treatment with erdafitinib and for 1 month after the last dose. Pregnancy testing is recommended for females of reproductive potential prior to initiating treatment with erdafitinib, and the drug may cause harm to a developing fetus or newborn baby.

Reference

FDA approves first targeted therapy for metastatic bladder cancer [news release]. Silver Spring, MD; April 12, 2019: FDA website. https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm635906.htm. Accessed April 12, 2019.