Merck expects to hear back from the FDA by the end of the year, said spokeswoman Pam Eisele. The Whitehouse Station, N.J., drug maker had expected a response from FDA before next week’s meeting of a vaccine advisory committee of the U.S. Centers for Disease Control & Prevention.
An FDA spokeswoman said it’s agency policy not to comment on ongoing reviews.
The vaccine is approved for use in girls and women ages 9 to 26, to prevent infection by certain types of the human papillomavirus, or HPV, which can cause cervical cancer and genital warts. Last year, the FDA approved Gardasil’s use in males ages 9 to 26 to prevent genital warts caused by HPV.
Merck began seeking regulatory approval more than two years ago to expand Gardasil’s use to include women up to 45, based on a study showing it was effective in the older age group at preventing precancerous lesions caused by HPV types that are targeted by the vaccine, after about two years of follow-up.
But the FDA delayed approval because it wanted to see longer-term data on Gardasil’s efficacy, after four years of follow-up. Merck submitted that data to FDA in late 2009 and hasn’t publicly disclosed the results.
Gardasil sales rose quickly after the product’s introduction in 2006 but have slowed in recent years, as Merck has encountered difficulty persuading women 19 to 26 to get the shot, and now faces competition from GlaxoSmithKline PLC’s (GSK) Cervarix. Merck’s Gardasil sales fell 20 percent, to $1.1 billion, last year. The shot is sold in most major European markets by Merck’s joint venture with Sanofi-Aventis SA (SNY).
Also, the vaccine has been dogged by safety concerns, including reports of fainting and blood clots. But last year U.S. health authorities said the vaccine’s benefits continue to outweigh any risks.
Merck shares fell 4 cents, to $35.98, Wednesday afternoon.