On August 15, 2019, the FDA accelerated the approval of entrectinib (Rozlytrek; Genentech), an oral kinase inhibitor, for the treatment of adults and adolescents whose cancer involves neurotrophic tyrosine receptor kinase (NTRK) gene fusion that has no effective treatments. The FDA granted entrectinib a priority review and breakthrough therapy and orphan drug designations. This is the third cancer drug approved by the FDA based on a common biomarker and the second drug for patients with NTRK gene fusion.
“We’re seeing continued advances in the use of biomarkers to guide drug development and the more targeted delivery of medicine,” said FDA Acting Commissioner Ned Sharpless, MD. “Today’s approval includes an indication for pediatric patients, 12 years of age and older, who have NTRK fusion–positive tumors by relying on efficacy information obtained primarily in adults,” said Richard Pazdur, MD, Director of the FDA’s Oncology Center of Excellence.
On the same day, the FDA also approved entrectinib for the treatment of adults with metastatic non–small-cell lung cancer (NSCLC) and a ROS1 mutation.
Entrectinib was evaluated in 4 clinical trials with 54 adults with NTRK fusion–positive tumors. The overall response rate (ORR) was 57%, including 7.4% complete responses, with entrectinib. Of the 31 patients with overall response, 61% had responses lasting 9 months or longer. The most common cancer locations were the lung, salivary gland, breast, thyroid, and colon/rectum.
The clinical trials also included 51 adults with ROS1-positive lung cancer. The ORR for those patients was 78%, including 5.9% complete responses. Among the 40 patients with NSCLC whose tumor responded to treatment with entrectinib, 55% had responses lasting 12 months or longer.
The most common side effects with entrectinib were fatigue, constipation, dysgeusia, edema, dizziness, diarrhea, nausea, dysesthesia, dyspnea, myalgia, cognitive impairment, weight gain, cough, vomiting, fever, arthralgia, and vision disorders. The most serious side effects were congestive heart failure, central nervous system effects, skeletal fractures, hepatotoxicity, hyperuricemia, QT prolongation, and vision disorders.