FDA warns about increased risk of muscle Injury with Merck & Co's Zocor at high dose; asks for more data on AP Pharma's APF 530

US patients and health care providers were warned by the Food and Drug Administration last Friday about the potential for increased risk of muscle injury from the now off-patent but once blockbuster cholesterol-lowerer simvastatin at the top approved dosage of 80mg.

Simvastatin is marketed as a single-ingredient generic and as the brand-name Zocor by US drug giant Merck & Co, which also is sells it in combination with ezetimibe as Vytorin, and in combination with niacin as Simcor. Simvastatin, which is also part of Merck's cholesterol drug Vytorin and Abbott Laboratories' drug Simcor, is sold by 11 other generic drug makers including Indian-owned Dr Reddy's Laboratories, Israel's Teva Pharmaceutical Industries, and Swiss drug major Novartis' Sandoz division.

Although muscle injury - or myopathy - is a known side effect with all statins, the latest warning highlights the greater risk of developing muscle injury, including rhabdomyolysis, for patients when they are prescribed and use higher doses of this drug. Rhabdomyolysis is the most serious form of myopathy and can lead to severe kidney damage, kidney failure, and sometimes death.