HPV Vaccine Stirs Economic Debate

While a debate rages over the morality of giving girls as young as nine Merck & Co.'s new Gardasil vaccine against the sexually transmitted human papillomavirus, a separate economic concern is emerging over the vaccine's hefty price and its impact on the nation's health-care costs.

After gaining regulatory approval on June 8, Merck's Gardasil was priced at $360 for a three-shot regimen, making it one of the priciest vaccines now on the market. The vaccine would be given to adolescent girls to reduce their risk of HPV-linked cervical cancer later in life. Immunizing 12-year-old girls alone could cost insurers and the government up to $700 million a year just for the vaccine.

Merck and others argue that when Gardasil's costs are compared with its potential impact on women's health, the vaccine could be considered a bargain. Some studies have found that the vaccine would be cost effective by providing additional protection against cervical cancer, reducing the frequency of abnormal pap smears and allowing screening to be conducted less frequently. Other experts argue that much is still unknown about the vaccine, such as whether booster shots will be needed and how widely it will be adopted.

The question of cost effectiveness will be among the issues discussed at the Centers for Disease Control and Prevention today and tomorrow, when the Advisory Committee on Immunization Practices meets to formulate its recommendations regarding HPV vaccines. The ACIP will consider whether girls and women should be vaccinated, the recommended ages for the shot, whether a booster is needed, and -- most crucially for the drug's maker -- whether the vaccination should be part of a routine immunization regimen.
Some opponents have argued that inoculating girls against a sexually transmitted disease might send the message that sexual activity is acceptable. Public comments along these lines may occur at the meeting.

The CDC's recommendations serve as best-practice guidelines for doctors. Insurers often follow the CDC recommendations in covering the cost of vaccinations. Merck has a strong track record winning recommendations for its childhood vaccines, but Gardasil is unusual because it targets a young population in order to prevent a fairly rare cancer in the U.S. that usually doesn't strike until middle age or later.

HPV infection is a significant cause of cervical cancer, which each year is diagnosed in an estimated 9,700 women (by comparison, there are 215,000 breast-cancer diagnoses a year). Gardasil aims to prevent infection from four strains of the HPV virus, including two strains that are considered high-risk for cancer. Many other HPV strains also exist.
The cost of cervical-cancer detection and treatment is high. Pap smears, which look for early signs of cancer, cost about $30 a test, and follow-up testing required for abnormal Paps is even more expensive. Treating cervical cancer costs the Medicare system alone about $1.7 billion a year.

Many of the cost-benefit studies done to date involved Merck or GlaxoSmithKline PLC, which is also developing an HPV vaccine. In many studies, including some done independent of drug companies, HPV vaccines like Gardasil appear cost effective if used to inoculate 12-year-old girls, giving them a booster shot five to 10 years later, and providing Pap smears every two or three years. The studies generally calculate cost effectiveness as a measure of the quality years of life that the intervention saves across the population.

Although there's no formal rule, interventions under $50,000 to $100,000 per quality-adjusted life year are generally considered cost effective. Vaccines for measles and mumps are so cost effective they actually save money. On the other hand, Pap smears, which test for early signs of cervical cancer, run anywhere from $150,000 to $1 million per quality-adjusted year of life saved if given annually rather than every three years, health-services researchers say.

These analyses also raise questions of exactly how many girls need to be vaccinated in order for rates of infection -- and later cervical cancer -- to decrease in the population as a whole.
Gillian Sanders, a cost-effectiveness analyst at Duke Clinical Research Institute, has conducted two HPV vaccine cost-effectiveness studies. Dr. Sanders's analysis shows that because of "herd immunity" -- when a vaccine's impact goes beyond just the people who are inoculated -- only about 70% of girls need to be vaccinated to bring the rate of cervical cancer down significantly in the population as a whole.
Many nations, including England, Australia, and Canada, use cost-effectiveness information to help make coverage and pricing decisions about treatments. The U.S. tends to shy away from formally using the information. Medicare, for instance, doesn't take costs into account in coverage decisions. The government-run vaccine fund for uninsured children doesn't either.

Cost-effectiveness calculations, however, can vary tremendously depending on what is included in the models, according to Marthe Gold, a professor at City College of New York who organized the U.S. Panel on Cost-Effectiveness in Health and Medicine in the 1990s that examined inconsistencies in how such analyses were conducted.
And some factors can't be predicted, such as whether another strain of HPV will develop if the currently most prevalent strains are eliminated. Data from Merck's Phase II and III trials suggest that no type replacement occurred in those studies, according to Merck spokeswoman Mary Elizabeth Blake, but Merck will be watching closely to see what happens to the HPV viruses when the vaccine is introduced.
Another issue is just how long the vaccine will be effective. So far the data show that the vaccine is good for at least five years, according to Ms. Blake.