FDA Approves Gomekli, First and Only NF1-PN Treatment for Both Children and Adults

The FDA has approved SpringWorks Therapeutics’ Gomekli (mirdametinib) for the treatment of adult and pediatric patients with neurofibromatosis type 1 who have symptomatic plexiform neurofibromas not amenable to complete resection (NF1-PN) according to a news release.

Gomekli is a MEK inhibitor available in 1 mg and 2 mg capsules as well as a 1 mg tablet which dissolves in water. The company estimates it will be available in the United States within the next two weeks through a specialty pharmacy.

Neurofibromatosis type 1 (NF1) is a genetic disorder that results in a mutation of the NF1 gene, neurofibromin, that controls cell growth and prevents tumors. In the United States, it affects about 100,000 children and adults in the United States. Patients with NF1 have a 30 to 50% lifetime risk of developing plexiform neurofibromas, or PNs, which are tumors along the peripheral nerve sheath.

There are approximately 40,000 NF1-PN patients in the United States, most of whom are adult patients with no prior treatment options until Gomekli. Compared to the rest of the population, NF1-PN patients have an eight-to-15-year reduction in life expectancy. Due to the complexity of the tumors, 85% are considered not surgically amenable.

The FDA’s approval is based on the results from the single-arm, phase 2b ReNeu study which enrolled 58 adult and 56 pediatric NF1-PN patients who received 2 mg of Gomekli twice daily for the first 21 days of each 28-day cycle. A confirmed response lasting at least 12 months was seen in 90% of pediatric patients and 88% of adult patients. The median best percentage change in tumor volume from baseline was -41% in adults and -42% in children. The objective response rate was 44% in adults and 52% in children.

Adverse events were reported in more than 25% of adult and pediatric patients. The most common side effects were rash (90% of adults, 73% of children), diarrhea (59% of adults, 55% of children) and musculoskeletal pain (41% of both adults and children).

“NF1-PN is a complex, devastating disease that affects not only individual patients, but entire families,” Kim Bischoff, executive director of the NF Network said in the news release. “Treatment advances are crucial to achieving better outcomes for patients and this FDA approval offers hope for NF patients and their families.”

Pricing, financial support and access information is available at www.springworkstxcares.com or by calling 1-844-CARES-55 (1-844-227-3755).