There was more good news for Merck & Co after it emerged that US regulatory advisors have given the thumbs up for the approval of Gardasil for the prevention of anal cancer and anal intraepithelial neoplasia (AIN).

Merck said yesterday the US Food and Drug Administration’s Vaccines and Related Biological Products Advisory Committee believes data contained within its marketing application indeed support an indication for Gardasil [Human Papillomavirus Quadrivalent (Types 6, 11, 16, and 18) Vaccine, Recombinant] to protect men and women aged nine to 26 years old from anal cancer and AIN.

The vaccine’s efficacy against HPV-related anal disease was assessed in men who have sex with men “because of the known high risk of anal infection and disease that occurs in this group” the firm said, but added that its application also includes for the treatment of woman as the disease affects both sexes.

The company’s US filing includes data from a Phase III trial, first unveiled back in February, which showed Gardasil prevented 77.5% of HPV 6, 11, 16, and 18-related AIN and anal cancer, clearly demonstrating its potential protective effects for patients.

Anal cancer is relatively uncommon, affecting around 5,000 people in the US every year, but up to 90% of cases are caused by the HPV virus, with the subtypes 16 and 18 sharing responsibility for around 80% of these. But although the market is not huge, Gardasil’s sales - $316 million in the last quarter - will undoubtedly benefit from an approval in this indication, which could give the vaccine a competitive edge over GlaxoSmithKline’s rival cervical job Cervarix.

Gardasil is already on the market for use in girls and young women for the prevention of cervical, vulvar and vaginal cancers caused by HPV types 16 and 18, genital warts caused by HPV types 6 and 11, and precancerous or dysplastic lesions caused by HPV types 6, 11, 16 and 18. In addition, the jab is also approved for use in males aged nine to 26 years of age for the prevention of genital warts caused by HPV types 6 and 11.