The U.S. Food and Drug Administration has released its latest list of possible drug safety concerns, citing Roche's breast cancer drug Herceptin and Sanofi Aventis' heart drug Multaq, among others.

The list, which comes out quarterly, covers safety issues that the FDA flagged between April and June and was released on the agency's website on Friday.

Other drugs listed include Merck & Co Inc's birth control Implanon, Pfizer's antibiotic Cleocin and Novartis' Afinitor.

Takeda Pharmaceutical's gout management drug Uloric, AMAG Pharmaceutical's anemia drug Feraheme and Shire Plc's phosphate binder Fosrenol were also included, among others.

In most cases, the FDA offered few clues into what the concerns were and simply said the agency is continuing to evaluate this issue to determine the need for any regulatory action.

Merck's cholesterol drug Zocor, Genentech's HIV drug Invirase and various GnRH agonists were also listed, but the agency has already issued more specific safety alerts on those drugs. Genentech is a unit of Roche.

Johnson & Johnson's Nucynta, a pain treatment, was also listed as having a risk of convulsions, hallucinations and serotonin syndrome.

FDA also named omeprazole products, used to treat ulcers, saying there is a risk the drug could cause low levels of magnesium in the blood.

The drug manufacturers were not immediately available for comment.

The list is online at: