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Gadrasil Could Prove Effective in Men too

by Gopalan on Jul 8 2007 11:35 AM

Gardasil, the new cervical cancer vaccine manufactured by Merck & Co., could be a potent weapon against sexually transmitted diseases (STDs) and one day prove effective in men too, commentators feel.

According to the US Food and Drug Administration (FDA), Gardasil is a safe and effective drug and it is clearly part of the new frontier of cancer meds. Gardasil does not target cancers directly but the viruses that can lead to the disease, it is pointed out.

The vaccine works by boosting the immune system so that it effectively fights off two of the most common strains of human papilloma virus, the most prevalent STD in modern society. In North America, HPV is said to infect half of all sexually active women between 18 and 22.

In most women, HPV clears up on its own but for some, the infection persists and can lead a couple of decades later, when they are in their prime child-rearing years, directly to cervical cancer, one of the top killers of women around the world.

By most estimates as many as 250,000 women, most of them in less-developed countries, die each year of cervical cancer and French researchers have said that number could jump fourfold by 2050 if nothing is done.

In Canada, about 400 die from the disease each year and another 1,350 or so are diagnosed with it. Health Canada is following the U.S. decision and approving Gardasil for use on girls and women aged nine to 26 - or before they become sexually active. Health Canada gave the approval on July 18, 2006, and the vaccine is now available through Canadian doctors and pharmacists.

However, the decision is not without controversy. At $360 US for a course of three treatments, Gardasil takes its place as the most costly vaccine on the planet.

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For manufacturer Merck & Co., the giant drug-maker that is still reeling from the recall of its once celebrated painkiller Vioxx, Gardasil is seen as something of a corporate life raft.

Analysts say U.S. sales alone would top $1 billion US a year, assuming Gardasil becomes covered by private insurance plans and at least some government programs.

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That number could jump to $4 billion a year if Merck comes out with a similar, perhaps identical, vaccine for young men, which it is actively working on.

(The issue with men seems to be simply one of ample testing: Until fairly recently, researchers report, men have rebelled against having swabs taken from the inside of their penis.)

The value of the drug could also go up if a growing lobby of health groups has its way. Already U.S. doctors are saying that leaving Gardasil to those families with private insurance or hit-and-miss government programs is creating an unconscionable Sophie's choice or roulette game in which certain young women would be left vulnerable to a preventable type of cancer and others are not.

In Canada, the federal government announced in its March 2007 budget that $300 million over three years will be available to the provinces and territories in support of a national vaccination program. The Conservative government noted that when new vaccines become available, it's critical to make them available to Canadians as soon as possible.

On June 20, 2007, the Nova Scotia government announced Gardasil will be offered to seventh grade girls as part of the school-based vaccination program and will not be mandatory.

The catch with Gardasil, though, is that it has proved remarkably effective against two particular strains of HPV, which in themselves are said to be responsible for upwards of 70 per cent of cervical cancers. That means Gardasil will not prevent all cervical cancers and women are still advised to get Pap tests.

But the important consideration here is that if young women have already been exposed to these two most popular strains, the vaccine has no effect. In fact, some early testing has suggested that women who take Gardasil who are already infected with HPV are more susceptible to developing the lesions that lead to cervical cancer. So the plan is to inoculate girls as young as possible, before they've had sex, hence the FDA decision to allow the drug on girls as young as nine, or when they are in Grade 4.

Not surprisingly, perhaps, the suggestion that grade-school aged girls be inoculated has caused a stir among social conservatives in the U.S. who argue that such a vaccine would only encourage promiscuity and a false sense of invulnerability to sexual disease.

But it appears to be popular among parents of young girls, according to surveys, and at least some religious groups are viewing it as a valid health response.

Social taboos in Third World countries may prove powerful disincentives to breaking the back of cervical cancer, aid workers apprehend.

The Bill and Melinda Gates Foundation has given almost $28 million US to an international health group to try to figure out how to introduce a female-only HPV vaccine into socially-conservative countries like India, Uganda, Peru and Vietnam, where infection rates have been soaring and the prospect of many more women dying of cervical cancer in the years ahead is very real.

In fact, reaching these societies — and perhaps the broader male market in North America at the same time — may be the reason Merck included in Gardasil an extra vaccine against two other HPV strains that cause relatively harmless genital warts.

Merck says it did this because the wart strains can confuse HPV screening tests and cause unnecessary anxiety among patients.

Some researchers, however, have said that this grouping will encourage men to get vaccinated to prevent disfiguring warts, and as a result they will no longer transmit the cancer-causing HPV strains to women.

Source-Medindia
GPL/C


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