The FDA has granted orphan drug designation to a cancer stem cell inhibitor known as VS-6063, or defactinib, for use in the treatment of mesothelioma, a rare form of lung cancer.
Orphan drug designation is given to novel drugs or biologics used as treatment for rare diseases or conditions affecting fewer than 200,000 people in the United States. The designation entitles defactinib developer Verastem, Inc. (Cambridge, Massachusetts) to FDA assistance in clinical trial design, exemption from FDA user fees, and a seven-year period of market exclusivity in the United States after product approval.Verastem is expecting approximately 350 to 400 persons with malignant pleural mesothelioma to enroll in a double-blind, placebo-controlled trial of defactinib. The study will be conducted at clinical sites in 11 countries.
Another lung cancer therapy, afatinib (Gilotrif), received FDA approval for use in persons with metastatic non–small cell lung cancer (NSCLC) whose tumors express the epidermal growth factor receptor (EGFR) exon 19 deletions or exon 21 L858R substitution gene mutations. Afatinib, a tyrosine kinase inhibitor, improved progression-free survival (PFS) in a multicenter, international, open-label, randomized trial of 345 persons with metastatic NSCLC whose tumors tested positive for these mutations. Median PFS was 11.1 months among the 230 patients receiving afatinib, compared with 6.9 months among the 115 patients undergoing chemotherapy (pemetrexed/cisplatin).
Fatal adverse reactions in persons receiving afatinib included pulmonary toxicity/interstitial lung disease–like adverse reactions (1.3%), sepsis (0.43%), and pneumonia (0.43%). Serious adverse reactions were reported in 29% of patients receiving afatinib; the most frequent of these were diarrhea (6.6%), vomiting (4.8%), and dyspnea, fatigue, and hypokalemia (1.7% each).
Afatinib was approved concurrently with the therascreen EGFR® RGQ PCR Kit. This companion diagnostic test helps determine whether lung cancer cells express the EGFR mutations noted.
In other FDA news related to diagnostic tests for cancer, Roche (Basel, Switzerland) has submitted a Premarket Approval supplement to the FDA, seeking the addition of a cervical cancer primary-screening indication for the cobas® HPV Test.
The test received was approved in April 2011 for the screening of women aged 21 years and older who had abnormal Pap test results and for the cotesting, with Pap, to assess the presence or absence of high-risk human papillomavirus (HPV) genotypes in women aged 30 to 65 years. According to Roche, the cobas HPV Test is the only FDA-approved test that provides pooled results for known high-risk genotypes and simultaneously provides individual results for the two highest-risk genotypes, HPV 16 and HPV 18.