On Friday, the FDA approved crizotinib (Xalkori) to treat ALK-positive patients with late-stage non–small cell lung cancer (NSCLC).
A diagnostic test used in tandem with the drug was also approved by the FDA. The Vysis ALK Break Apart FISH Probe Kit is the first test of its kind to identify patients with an abnormal ALK
Crizotinib is an oral compound that blocks signaling in cell pathways by inhibiting kinases, including the protein produced by the abnormal ALK
gene. The drug is taken twice a day as a single-agent therapy.
Earlier this year, the drug showed marked antitumor activity in a study presented at the 14th World Conference on Lung Cancer in Amsterdam. In early phase II results from the single-arm, open-label PROFILE 1005 trial, 51% of 133 patients who had undergone prior chemotherapy who were treated with crizotinib exhibited an overall response, including 1 patient who experienced a complete response. At 12 weeks into the trial, the disease control rate was 74%, meaning that a proportion of participants achieved stable disease, or partial or complete responses.
Further studies confirmed crizotinib’s effectiveness in treating patients with NSCLC. A total of 255 patients with late-stage ALK-
positive NSCLC were studied in 2 multicenter, single-arm trials.
In one study, the objective response rate was 50%, with a median response duration of 42 weeks. In another, the objective response rate was 61%, with a median response duration of 48 weeks.
The FDA approved crizotinib under its accelerated approval program because of its ability to treat a serious disease based on clinical data showing that the drug is likely to create a clinical benefit in patients.
The diagnostic test that accompanies crizotinib is a major part of the approval. It is the second targeted therapy to have such a test approved by the FDA this year.
“The approval of Xalkori with a specific test allows the selection of patients who are more likely to respond to the drug,” said Richard Pazdur, MD, director of the Office of Oncology Drug Products in the FDA’s Center for Drug Evaluation and Research, in a statement released on Friday. “Targeted therapies such as Xalkori are important options for treating patients with this disease and may ultimately result in fewer side effects.”