FDA Approves Mitomycin Gel for Upper Tract Urothelial Cancer

The FDA granted approval to UroGen Pharma for mitomycin gel (Jelmyto), the first therapy to treat low-grade upper tract urothelial cancer (UTUC). 

“This is the first approval specifically for patients with low-grade UTUC and provides an option for some patients who may otherwise require a nephroureterectomy,” Richard Pazdur, MD, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Oncologic Diseases in the FDA’s Center for Drug Evaluation and Research, said in a press release. “Due to substantial treatment challenges associated with the complex anatomy of the upper urinary tract, many patients need to be treated with radical surgery – usually complete removal of the affected kidney, ureter and bladder cuff. Jelmyto gives patients, for the first time, an alternative treatment option for low-grade UTUC.”

The approval was based on results from a clinical trial which included 71 patients with low-grade UTUC. These individuals had never undergone treatment or had low-grade non-invasive UTUC with at least 1 measurable papillary tumor.

Participants received mitomycin gel once a week for 6 weeks. If they were then evaluated as having a complete response, defined as complete disappearance of the papillary tumor, then received the gel monthly thereafter for up to 11 additional months. Efficacy of mitomycin gel was evaluated using urine cytology, ureteroscopy, and biopsy (if warranted) 3 months following the initiation of therapy. 

A complete response was found in a total of 41 patients (48%) following 6 treatments of mitomycin gel administered weekly. Moreover, durability of the effect of the gel in patients with a complete response was also assessed using urine cytology, ureteroscopy, and biopsy (if warranted) every 3 months for a year following the initiation of therapy. Overall, 19 patients (46%) who achieved a complete response continued to have a complete response at the 12-month mark. 

“Although our nation’s emphasis is on the need to combat COVID-19, patients with cancer and their unique needs continue to be a top priority for the FDA,” Pazdur said. “We continue to expedite oncology product development in this critical time. Our staff is continuing to meet virtually with drug developers, academic investigators and patient advocates to push forward the coordinated review of drugs, biologics and devices for cancer.”

Common side effects observed in patients taking mitomycin gel included ureteric obstruction, flank pain, urinary tract infection, hematuria, renal dysfunction, fatigue, nausea, abdominal pain, and vomiting. Further, mitomycin gel can also cause serious side effects such as urosepsis.

Patients with ureteric obstruction could require transient or long-term stents to relieve this obstruction. Additionally, the obstruction may be persistent, as it did not resolve or did not resolve completely in 51% of patients who experienced obstruction due to treatment with mitomycin gel. Treatment should also be avoided in patients with a glomerular filtration rate of less than 30 mL/min.

It has also been recommended that women who are pregnant not take mitomycin gel, because it may cause harm to a developing fetus or newborn baby. The FDA advised that healthcare professionals tell females of reproductive age to use effective contraception throughout treatment with mitomycin gel, and for 6 months following the last dose. Moreover, male patients who have female partners of reproductive potential should also use effective contraception during treatment with mitomycin gel and for 3 months following the last dose. 

The FDA previously granted the application for mitomycin gel priority review and breakthrough therapy designation. Mitomycin gel was also granted fast track designation and received orphan drug designation. 

Reference:

FDA Approves First Therapy for Treatment of Low-Grade Upper Tract Urothelial Cancer [news release]. Published April 15, 2020. fda.gov/news-events/press-announcements/fda-approves-first-therapy-treatment-low-grade-upper-tract-urothelial-cancer?utm_campaign=FDA%20Approves%20First%20Therapy%20for%20Treatment%20of%20Low-Grade%20Upper%20Tract%20Urothelial%20Cancer&utm_medium=email&utm_source=Eloqua. Accessed April 15, 2020.