Philadelphia – The push for a vaccine to eradicate most cases of deadly cervical cancer worldwide moved closer to realization Thursday with Merck & Co.’s announcement that short- term studies have shown its drug to be 100 percent effective in combating the virus that causes the disease.
The studies tested Merck’s Gardasil vaccine for six months on more than 12,000 women in 13 countries.
Merck officials hope to sell the drug, if approved by the Food and Drug Administration, in the U.S. by sometime next year.
Several ongoing studies have shown that both Gardasil and a competing drug being developed by GlaxoSmithKline, called Cervarix, effectively protect women against two strains of the sexually transmitted human papillomavirus. The virus causes 70 percent of all cervical cancer cases.
Worldwide, the cancer kills 270,000 women a year, about 4,000 of them in the United States.
With the new vaccines, “cervical cancer could be controlled by vaccination the way polio has been,” said Kevin Ault, an Emory University ob-gyn who is one of Gardasil’s principal U.S. investigators.
But before that happens, cervical-cancer vaccines must win not only regulatory approval but also acceptance by millions of parents who will have to decide if they should vaccinate daughters as young as 9 or 10 against a sexually transmitted disease.
To work, the vaccines – which can be given to both females and males – ideally should be administered before people become sexually active.
Conservative groups including the Family Research Council have already raised concerns that giving a sex-related vaccine to young people might encourage them to have early sex.
In the United States, the cervical-cancer death rate is low because most women have the disease detected by Pap smears before it advances.
Those critical tests are not available to most women in the developing world. Both Glaxo and Merck, the latter still struggling from the abrupt withdrawal of its blockbuster painkiller Vioxx last year, can hope to sell the vaccines to millions of women worldwide.
The latest Merck studies enrolled sexually active female volunteers ages 16 to 26, who were given the recommended three doses of Gardasil over six months and then tested for either cervical cancer or pre- cancerous cervical lesions.
All of those who received the drug remained disease-free after being followed an average of 17 months, Merck said. In a subgroup of women who received one dose of the drug, only one showed evidence of disease – an efficacy rate of 97 percent.
But questions about the drugs remain.
A critical one is whether the vaccines will retain their effectiveness for many years.
