The FDA gave the nod to several generics firms to market copycat versions of the over-the-counter allergy drug Zyrtec (cetirizine).

Among the nine companies listed on FDA's Web site as having receiving approval are Mylan, which is the world's third-largest generics maker, Perrigo and Caraco Pharmaceutical Laboratories. The FDA had tentatively approved the applications in 2004, pending expiration of the drug's patents.

Johnson & Johnson won FDA approval to sell nonprescription Zyrtec in November after buying rights to the product in its $16.6-billion purchase of Pfizer's consumer unit in December 2006. J&J said it plans to launch the OTC version in January 2008 through its McNeil Consumer Healthcare unit.

McNeil will also distribute Zyretc-D 12 Hour (cetirizine HCl 5 mg/pseudoephedrine HCl 120 mg), which combines Zyrtec with a decongestant.

Zyrtec sales for the 12 months ending October 2007 were approximately $1.4 billion, according to Wolters Kluwer data cited by Perrigo.