Zocor, 13 Other Drugs, Make FDA List of Medications of Concern

Federal drug safety regulators have released their quarterly list of medications they are monitoring based on adverse event reports received during the second quarter of 2010. Included on the list are 14 medications, including the popular cholesterol drug Zocor, which has been linked to a serious and potentially life-threatening muscle disease known as rhabdomyolysis. 

Several times a year, the FDA releases a list of drugs identified by the agency’s adverse events reporting system as showing potential signs of serious risks. The list is generated by the frequency and types of adverse event reports the FDA receives from doctors and patients. Being on the list does not mean that a drug has been shown to have that risk, only that the FDA has received a number of reports that has raised concerns.

From April through June of 2010, the FDA identified potential signals for serious risk associated with Cleocin, Multaq, Implanon, Afinitor, Uloric, Feraheme, Androgen Deprivation Therapy, Fosrenol, Zocor, Invirase, Nucynta, Heceptin, omeprazole products and tetracycline products.

The FDA previously initiated a safety review on three of the medications, including Zocor. The other two drugs that were already under review are Invirase, an HIV drug which may disrupt electrical activity in the heart; and Androgen Deprivation Therapy, which is a class of prostate cancer drugs known as GnRH agonists that could increase the risk of diabetes and cardiovascular disease such as heart attack, cardiac arrest and sudden death.

In March, the FDA warned that Zocor users had an increased risk of rhabdomyolysis when taking the drug at high doses of 80 mg. While all statins carry some risk of the muscle injury, the FDA’s report was the first time a dose-specific connection had been made to a particular drug. Symptoms of rhabdomyolysis from Zocor could include muscle cramps, tenderness, stiffness, pain or spasms. The illness is usually reported in patients over 65 years of age or those who have renal impairment or uncontrolled hypothyroidism.

Zocor (simvastatin) is a synthetic statin developed by Merck & Co., which is now available as a generic. Before patent protections expired in 2005, it was Merck’s best-selling drug and the second best selling cholesterol lowering drug in the world, bringing in $4.3 billion in 2005.

Invirase (saquinavir) is an antiretroviral medication manufactured by Genentech, which is a subsidiary or Roche AG. The drug was first approved in 1995. It is often used in combination with Abbott Laboratories’ Norvir (ritonavir), another antiretroviral drug approved by FDA in 1996.

In February, the FDA reported that when Invirase and Norvir are used together they could increase the risk of heart abnormalities leading to irregular heart rhythms. The abnormal heart rhythms, a condition called torsades de pointes, can cause fainting, lightheadedness and could leave to life-threatening irregular heart beats.

The safety review of GnRH Agonists was launched in May. The drugs lower male hormones, which can cause prostate tumors to shrink and can slow the progress of prostate cancer. The drugs are sold under the brand names Lupron, Zoladex, Trelstar, Viadur, Vantas, Eligard and Synarel. The FDA became concerned after six different studies showed a small increase in the risk of diabetes and cardiovascular disease.

The complete list of medications and potential signals of serious risks identified can be found on the FDA website.