FDA Approves Mitomycin for Adults With Upper Tract Urothelial Cancer

On April 15, 2020, the FDA approved mitomycin (Jelmyto; UroGen Pharma) for the treatment of adults with low-grade upper tract urothelial cancer (UTUC). The application for this approval was granted priority review, fast track, and breakthrough therapy designations by the FDA.

The efficacy of mitomycin was based on findings from the ongoing, multicenter OLYMPUS clinical trial of 71 patients with treatment-naïve or recurrent low-grade non-invasive UTUC and at least 1 measurable papillary tumor located above the ureteropelvic junction. Notably, patients with larger tumors could have had previous tumor debulking.

Patients in the study were given weekly mitomycin 4 mg per mL instillations via ureteral catheter or nephrostomy tube for a total of 6 weeks. Patients achieving a complete response (CR; defined as complete absence of tumor lesions 3 months after mitomycin initiation) at 3 months, were given instillations monthly for a maximum of 11 additional instillations.

The major efficacy end points were CR and CR durability, with CR assessed via urine cytology and ureteroscopy (or, if warranted, a biopsy).

Overall, 41 (58%) patients achieved a CR 3 months after initiating treatment and continued with follow-up; 29 patients were given at least 1 dose of maintenance therapy.

At 3, 6, 9, and 12 months, the investigators evaluated response durability in patients achieving CRs. Seven of these patients had recurrences and 19 had CR persist at 12-months after CR determination. As of this approval date, the median response duration has not been reached.

The most frequently reported (≥ 20%) adverse reactions for mitomycin were ureteric obstruction, flank pain, urinary tract infection, hematuria, renal dysfunction, fatigue, nausea, abdominal pain, dysuria, and vomiting. Approximately 60% of patients had ureteric obstructions, 88% of whom required ureteral stent placement.—Hina Porcelli

Source: US Food and Drug Administration. FDA approves mitomycin for low-grade upper tract urothelial cancer. April 15, 2020. www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-mitomycin-low-grade-upper-tract-urothelial-cancer. Accessed April 15, 2020.