Virginia Ellen Maher

U.S. Food and Drug Administration Approval: Crizotinib for Treatment of Advanced or Metastatic Non–Small Cell Lung Cancer That Is Anaplastic Lymphoma Kinase Positive

On August 26, 2011, the U.S. Food and Drug Administration (FDA) approved crizotinib (XALKORI Capsules, Pfizer Inc.) for treatment of patients with locally advanced or metastatic non–small cell lung cancer (NSCLC) that is anaplastic lymphoma kinase (ALK) positive as detected by an FDA-approved test. The Vysis ALK Break-Apart FISH Probe Kit (Abbott Molecular, Inc.) was approved concurrently. In two multicenter, single-arm trials, patients with locally advanced or metastatic ALK-positive NSCLC previously treated with one or more systemic therapies received crizotinib orally at a dose of 250 mg twice daily. In 119 patients with ALK-positive NSCLC by local trial assay, the objective response rate (ORR) was 61% [95% confidence intervals (CI), 52%–70%] with a median response duration of 48 weeks. In 136 patients with ALK-positive NSCLC by the to-be-marketed test, the ORR was 50% (95% CI, 42%–59%) with a median response duration of 42 weeks. The most common adverse reactions (≥25%) were vision disorder, nausea, diarrhea, vomiting, edema, and constipation. Accelerated approval was granted on the basis of the high ORRs and durable responses. On November 20, 2013, crizotinib received full approval based on an improvement in progression-free survival in patients with metastatic ALK-positive NSCLC previously treated with one platinum-based chemotherapy regimen. Clin Cancer Res; 20(8); 2029–34. ©2014 AACR.

Radium Ra 223 dichloride injection: U.S. Food and Drug Administration Drug Approval Summary

On May 15, 2013, the U.S. Food and Drug Administration (FDA) approved radium Ra 223 dichloride (Ra-223; Xofigo injection; Bayer HealthCare Pharmaceuticals Inc.) for the treatment of patients with castration-resistant prostate cancer (CRPC), symptomatic bone metastases, and no known visceral metastatic disease. The FDA review was based on clinical trial BC1-06, which randomly allocated patients (2:1) to either Ra-223 plus best standard of care (BSoC) or placebo plus BSoC. The primary endpoint was overall survival (OS) with a key secondary endpoint of time to first symptomatic skeletal event (SSE). A statistically significant improvement in OS was demonstrated [HR, 0.70; 95% confidence interval, 0.55–0.88, P = 0.0019]. At the prespecified interim analysis, the median OS durations were 14.0 and 11.2 months in the Ra-223 and placebo arms, respectively. The improvement in OS was supported by a delay in time to first SSE favoring the Ra-223 arm. The most common (>10%) adverse reactions in patients receiving Ra-223 were nausea, diarrhea, vomiting, and peripheral edema. The most common (>10%) hematologic laboratory abnormalities were anemia, lymphocytopenia, leukopenia, thrombocytopenia, and neutropenia. Ra-223 is the first α-emitting radiotherapeutic and the first radiopharmaceutical to demonstrate an OS advantage in metastatic prostate cancer. Clin Cancer Res; 20(1); 9–14. ©2013 AACR.

Enzalutamide for Treatment of Patients with Metastatic Castration-Resistant Prostate Cancer Who Have Previously Received Docetaxel: U.S. Food and Drug Administration Drug Approval Summary

This article summarizes the regulatory evaluation that led to the full approval of enzalutamide (XTANDI, Medivation Inc.) by the U.S. Food and Drug Administration (FDA) on August 31, 2012, for the treatment of patients with metastatic castration-resistant prostate cancer who have previously received docetaxel. This approval was based on the results of a randomized, placebo-controlled trial which randomly allocated 1,199 patients with mCRPC who had received prior docetaxel to receive either enzalutamide, 160 mg orally once daily (n = 800), or placebo (n = 399). All patients were required to continue androgen deprivation therapy. The primary endpoint was overall survival. At the prespecified interim analysis, a statistically significant improvement in overall survival was demonstrated for the enzalutamide arm compared with the placebo arm [HR = 0.63; 95% confidence interval: 0.53–0.75; P < 0.0001]. The median overall survival durations were 18.4 months and 13.6 months in the enzalutamide and placebo arms, respectively. The most common adverse reactions (≥10%) included asthenia or fatigue, back pain, diarrhea, arthralgia, hot flush, peripheral edema, musculoskeletal pain, headache, and upper respiratory infection. Seizures occurred in 0.9% of patients on enzalutamide compared with no patients on the placebo arm. Overall, the FDAs review and analyses of the submitted data confirmed that enzalutamide had a favorable benefit–risk profile in the study patient population, thus supporting its use for the approved indication. The recommended dose is 160 mg of enzalutamide administered orally once daily. Enzalutamide represents the third product that the FDA has approved in the same disease setting within a period of 2 years. Clin Cancer Res; 19(22); 6067–73. ©2013 AACR.