Merck & Co Inc’s Gardasil, the first vaccine to prevent cervical cancer, was launched in Britain and Ireland on Tuesday in the latest phase of an unusually rapid rollout for the new product.

Sanofi Pasteur MSD, the joint venture between Merck and Sanofi-Aventis which is responsible for European sales, said it was also launched recently in Germany, Austria, Finland and Sweden.

Viewed by analysts as a potential multibillion-dollar-a-year seller, Gardasil is a new kind of vaccine that prevents cervical cancer by protecting against the sexually transmitted human papilloma virus (HPV) that triggers most cases of the disease.

The vaccine was given European regulatory approval last month and will be sold in Europe for an ex-factory price of between 300 and 360 euros ($375-450) for a course of three doses.

That translates into a consumer price of 450 to 600 euros, with the price varying due to country-specific factors, such as wholesaler and pharmacy mark-ups.

Sanofi Pasteur MSD aims to have Gardasil on the market in most European countries by the end of the year, though it will not be available in Spain, Italy and Greece until 2007.

It has already been launched in several countries outside Europe, including the United States, where it has been recommended by experts for use in girls as young as nine and young women up to age 26.

GlaxoSmithKline Plc has a rival anti-HPV product called Cervarix waiting in the wings.

Uptake of both vaccines will depend crucially on government recommendations for their use and funding.

The manufacturers received a boost earlier this month when the influential Lancet medical journal called for routine vaccination of all adolescent girls in European Union countries.

Cervical cancer is one of the most common cancers in women. Each year 470,000 women are diagnosed with the disease and 230,000 die. Most of the deaths are in the developing world.

The Lancet said there was growing support for vaccinating both girls and boys against the sexually transmitted virus but added more data from clinical trials in boys was needed.