US scientists are testing a new vaccine that protects against infection by nine of the most harmful strains of the human papillomavirus (HPV).

The vaccine is called nine-valent, and is being tested by researchers based at the Gynecologic Cancer Prevention Center in the Medical College of Georgia (MCG) in Augusta, Georgia, USA.

HPV causes cervical cancer and genital warts. The new vaccine is being compared to Gardasil, an HPV vaccine approved by the FDA last year that protects against infection by HPV types 16 and 18, known to cause 70 per cent of HPV-related cervical cancer, and types 6 and 11, responsible for 90 per cent of HPV generated genital warts.

Dr Daron Ferris, family medicine physician and director of the Center said:

“We’re testing Gardasil against three different doses of the investigational vaccine.”

“This study will determine the best dose of the new vaccine and whether it is safe, well-tolerated and effective in preventing HPV infection and disease compared with what’s already out there,” he added.

The new vaccine is expected to protect against the four HPV strains that Gardasil works against, plus five other strains that also cause cancer.

The new drug is similar to Gardasil in that it contains proteins that arrange themselves into a hollow ball that mimics the HPV’s protective shield, but it can’t actually cause an infection because it doesn’t have the viral DNA inside. However, the disguise is sufficient to fool the body into making antibodies against the real HPV.

“Women infected with those five types of HPV also have an increased risk of developing severe precancerous cervical disease and cervical cancer,” said Ferris.

“While genital warts go away on their own in most cases, cervical precancerous lesions are less likely to disappear without treatment,” he explained.

HPV cannot be cured, so the most effective strategy is prevention, and the only drug currently available is Gardasil. Lesions can be treated with topical creams and surgical removal while they are precancerous.

The study is designed so that all participants get a vaccine. There will be two groups, one taking the new vaccine and the other taking Gardasil.

Ferris describes this as a “win-win” because unlike the Gardasil trials where one group had a placebo, in this trial each participant will be vaccinated either against four or nine types of HPV.

The initial target group will be female participants aged from 9 to 26, since most HPV infections happen to girls and women aged between 15 and 25.

The participants will have to attend between 5 and 11 examinations over a seven month to a three and a half year period. Each visit will include a physical and a pelvic exam, a Pap smear to look for lesions, both cancerous and pre cancerous, and testing for the presence of HPV.

The researchers said the study is open to women who are in good health, not pregnant, aged between 16 and 26, and who have no history of abnormal Pap tests.

Further information on the study can be obtained from Dr Ferris’ office at MCG on 706-721-2535.

Click here for more information about the Gynecologic Cancer Prevention Center at MCG.

Written by: Catharine Paddock