The FDA has approved ripretinib (Qinlock, Deciphera Pharmaceuticals) tablets as a fourth-line treatment for advanced gastrointestinal stromal tumor (GIST), a type of tumor that originates in the gastrointestinal tract.

Ripretinib is indicated for adult patients who have received prior treatment with 3 or more kinase inhibitor therapies, including imatinib, according to an FDA press release.

The approval was based on the results of a clinical trial that enrolled 129 patients with advanced GIST who had received prior treatment with other FDA-approved targeted therapies—imatinib, sunitinib, and regorafenib. The trial compared patients who were randomized to receive placebo to determine whether progression-free survival (PFS) was longer in the ripretinib group compared with the placebo group.

Patients received ripretinib or placebo once per day in 28-day cycles repeated until tumor growth was found or the patient experienced intolerable adverse effects (AEs). After disease progression, patients who were randomized to placebo were given the option of switching to ripretinib.

The PFS rate in patients in the ripretinib group was 6.3 months compared with 1 month for patients in the placebo group, according to the press release.

The most common AEs with ripretinib were alopecia, fatigue, nausea, abdominal pain, constipation, myalgia, diarrhea, decreased appetite, palmar-plantar erythrodysesthesia syndrome, and vomiting. Serious AEs included skin cancer, hypertension, and cardiac dysfunction manifested as ejection fraction decrease.

FDA approves first drug for fourth-line treatment of advanced gastrointestinal stromal tumors. Silver Spring, MD; FDA: May 15, 2020. Accessed May 18, 2020.