FDA Approval Summary: Accelerated Approval of Pembrolizumab for Second-Line Treatment of Metastatic Melanoma.

On September 4, 2014, the FDA approved pembrolizumab (KEYTRUDA; Merck Sharp & Dohme Corp.) with a recommended dose of 2 mg/kg every 3 weeks by intravenous infusion for the treatment of patients with unresectable or metastatic melanoma who have progressed following treatment with ipilimumab and, if BRAF V600 mutation positive, a BRAF inhibitor. Approval was based on demonstration of objective tumor responses with prolonged response durations in 89 patients enrolled in a randomized, multicenter, open-label, dose-finding, and activity-estimating phase 1 trial. The overall response rate (ORR) by blinded independent central review per RECIST v1.1 was 24% (95% confidence interval, 15-34); with 6 months of follow-up, 86% of responses were ongoing. The most common (≥20%) adverse reactions were fatigue, cough, nausea, pruritus, rash, decreased appetite, constipation, arthralgia, and diarrhea. Immune-mediated adverse reactions included pneumonitis, colitis, hepatitis, hypophysitis, and thyroid disorders. The benefits of the observed ORR with prolonged duration of responses outweighed the risks of immune-mediated adverse reactions in this life-threatening disease and represented an improvement over available therapy. Important regulatory issues in this application were role of durability of response in the evaluation of ORR for accelerated approval, reliance on data from a first-in-human trial, and strategies for dose selection. Clin Cancer Res; 23(19); 5666-70. ©2017 AACR.

Rhabdomyolysis with HMG-CoA reductase inhibitors and gemfibrozil combination therapy.

CONTEXT: Elevated total cholesterol (total-C) and low-density lipoprotein cholesterol (LDL-C) levels are established risk factors for cardiovascular disease (CVD). HMG-CoA reductase inhibitors (statins) are effective cholesterol-lowering drugs that are commonly prescribed to treat this condition. These drugs are often combined with another class of drugs, fibric acid derivatives, to lower both cholesterol and triglyceride levels. Rhabdomyolysis is a known, rare serious side effect of statin monotherapy and of statin-fibrate combination therapy. OBJECTIVE: To examine Food and Drug Administration's (FDA's) postmarketing database for cases of rhabdomyolysis in relation to monotherapy and combination use and calculate reporting rates for this event. DESIGN: Domestic cases of statin- and statin/gemfibrozil-associated rhabdomyolysis were culled from FDA's database and reviewed. Rhabdomyolysis was defined by CPK > or = 10,000 IU/L, myopathic signs and symptoms and clinical diagnosis of rhabdomyolysis. Reporting rates, consisting of number of reported cases/number of prescriptions for each drug, were then calculated to determine whether the reporting of rhabdomyolysis cases was commensurate with extent of use of each statin in the population. SETTING: Cases were obtained from the FDA adverse event reporting system (AERS) database. PATIENTS: NA. MAIN OUTCOME MEASURES: Number of rhabdomyolysis cases were evaluated, along with outcomes, such as renal failure, dialysis and death. RESULTS: Of 866 total reported cases, 482 (56%) were associated with monotherapy and 384 (44%) related to combination therapy. More than 80% of reported cases for each drug resulted in hospitalization for renal failure and dialysis. 80 patients expired from events related directly to rhabdomyolysis. Reporting rates for all statins, except for cerivastatin, were similar and much lower than 1 per 100,000 prescriptions. The cerivastatin-reporting rate was much higher at 4.24/100,000 prescriptions. CONCLUSIONS: Rhabdomyolysis is a rare, serious side effect of statin monotherapy and of statin-fibrate combination therapy. Clinicians need to remain cognizant of this potential adverse event and discuss signs and symptoms of muscle toxicity with patients in order improve the benefits-to-risks of treating dyslipidemia with statins.