The U.S. Food and Drug Administration said Thursday that bottles of HIV drug Ziagen may have been mislabeled as Combivir, another HIV drug.
The FDA and GlaxoSmithKline, which makes both drugs, said it appears the bottles were tampered with by a third party that used counterfeit labels to mislead readers about the contents, WebMD reported Thursday.
GlaxoSmithKline said in a letter to pharmacists that no injuries have been reported from the tampering. However, Ziagen's active ingredient may cause hypersensitivity reactions in some patients that could be life threatening.
"These incidents appear to be isolated and limited in scope to one pharmacy in California," the FDA said.
The labels on the tampered bottles were identified as Lot No. 6ZP9760 with expiration dates of April 2010 and April 2009.
Combivir tablets are white and have "GX FC3" engraved on one side, while Ziagen tablets are yellow and read "GX 623" on one side.
Copyright 2007 by United Press International
Explore further: HIV can spread early, evolve in patients' brains