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Breakthrough HPV vaccine

By Lydia Shrier, MD, MPH

Breakthrough HPV vaccine approved to fight cervical cancer

The U.S. Food and Drug Administration recently approved Gardasil, the first vaccine to help prevent cervical cancer and other conditions caused by particular types of genital human papillomavirus (HPV). HPV is the most common cause of new sexually transmitted diseases and more than 20 million Americans currently have the virus. Gardasil protects against four types of HPV. Here, Dr. Lydia Shrier talks about the new vaccine and its impact on young women's health.

What is HPV?
It is a group of more than 100 different types of viruses, more than 30 of which are sexually transmitted. Low-risk types of HPV can lead to benign, but bothersome, genital warts or abnormal changes in the cervix, but generally don't progress to serious disease. However, high-risk types can lead to cervical cancer and, rarely, cancers of the vulva, vagina, anus or penis. There is no cure for HPV and a person can have more than one type.

What is Gardasil?
It's a vaccine recommended for females 9 to 26 years old to prevent them from getting four particular types of HPV: types 6 and 11, which cause 90 percent of genital warts, and types 16 and 18, which are responsible for 70 percent of cervical cancers. It's given as an intramuscular injection in a three-shot series over a six-month period. It doesn't treat existing HPV infections, genital warts, precancers or cancers.

How long has Children's offered the vaccine?
Gardasil has been available at Children's since mid-October of 2006.

How effective is it?
In females who had not been exposed to HPV types 6, 11, 16 or 18, studies have shown 100 percent efficacy in preventing cervical precancers and almost 100 percent efficacy in preventing vulvar and vaginal precancers and genital warts. The vaccine was less effective in young women who had already been exposed to one of the HPV types covered by the vaccine or those who missed a dose. We don't know if a booster shot will be needed in the future, but studies show that women are protected for at least five years from getting HPV.

Who should receive the Gardasil vaccine?
The Advisory Committee on Immunization Practices recommends it for 11 and 12 year old girls since it's critical that young women are vaccinated before they come in contact with HPV through sexual contact. But the vaccine can also be given to girls as young as 9 (at the medical provider's discretion) and to 13- to 26-year-olds, if they haven't already received the vaccine or completed the series.

Why hasn't it been approved for use in men?
While the vaccine is safe and effective in producing antibodies against HPV in males, there's just not enough research to support vaccinating them. Gardasil is expensive and the frequency of genital warts and certain cancers in males is relatively low, so officials haven't seen enough compelling evidence to approve the vaccine for males yet. With more research and studies, however, males may someday be vaccinated.

What would be the benefits of vaccinating men?
The primary purpose of vaccinating them would be to prevent infection in females—if males don't have HPV, they can't spread it to their female partners. Also, the vaccine could help males protect themselves from genital warts, anal and penile cancers and other conditions that result from HPV.

How does the vaccine work?
It's made of virus-like particles that look to the body like HPV, which encourages the body to make antibodies against it. So if and when you're exposed to HPV, you'd have antibodies so your body can fight and kill the virus. Gardasil isn't a live vaccine, which means it doesn't contain the actual virus. You can't get HPV from the vaccine.

Are there side effects?
The most common side effects are pain, swelling and redness at the injection site, and, rarely, people have had fever, nausea, dizziness or vomiting.

Should females continue to get screened for cervical cancer after getting the vaccine?
Yes. Since the vaccine does not protect against all types of HPV responsible for cervical cancer, sexually-active women should continue to have an annual gynecological screening for cervical cancer and other conditions.

Can women over 26 get the vaccine?
To date, the studies on Gardasil don't include women over 26, so the vaccine isn't approved for them at this time.

How much is it and will it be covered by insurance plans?
The current price is about $120 per dose, which comes to $360 for the full series of injections. Insurance companies are negotiating coverage of the vaccine now.

Are there other HPV vaccines in development?
GlaxoSmithKline is developing Cervarix, a vaccine targeting HPV types 16 and 18.

How valuable is this for women's health?
This vaccine is a big deal. We're talking about preventing a major type of cancer, which is momentous.

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