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HPV Vaccine More Effective Than Thought

HPV vaccine protects against “70 percent of cervical cancer caused by viruses” and may have “at least some effect against viral strains that cause the other 30 percent.”

But 75-95% of these viral infections go away on their own.

Should Boys Be Given the HPV Vaccine? The Science Is Weaker than the Marketing

Jeanne Lenzzer, Discover Magazine, 2011:

“On May 10, 2007, Merck published the results of a study in the New England Journal of Medicine that claimed an astounding 98 percent efficacy in preventing changes in the cervix used as a marker for cervical cancer.

“But that statistic begs closer examination.

“To achieve the 98 percent efficacy claim, Merck excluded from analysis anyone who “violated” the study protocol. In other words, all real-world problems that arose were excluded from analysis. Problems like girls who refused to take a second or third shot after they became sick and (correctly or incorrectly) blamed the vaccine. Or doctors who incorrectly gave the vaccine to someone who shouldn’t have received it.  While it’s worth knowing how effective the vaccine is when it’s used exactly as it should be, for a public-health decision, it’s not as relevant as its real-world effectiveness.

“To Merck’s credit, they reported that when all women in the study were analyzed, the vaccine’s efficacy dropped to 44 percent. Still, 44 percent might be considered a smashing success when you’re talking about saving lives. Except for one thing: the numbers get worse. The 44 percent benefit included only those women with the two specific cancer-causing HPV strains found in the vaccine. But when the researchers looked at negative cervical changes from any causes, they found that changes occurred in unvaccinated women at a rate of 1.5 events per 100 person-years, while vaccinated women had 1.3 events—dropping the benefit to 17 percent.

“Moreover, most of the cervical changes tracked by the researchers weren’t even indicative of cervical cancer in the first place. Most were innocent cellular abnormalities that either disappear entirely on their own, or never progress to cancer. In fact, when they looked more closely at advanced cervical changes most likely to progress to cancer versus more innocent changes that go away spontaneously, it was the innocent changes that accounted for the decline.”

“So how did the HPV vaccine become a multi-billion-dollar winner for Merck? Well you might not be surprised to hear that the company happily lavished money on doctors, professional societies, and over 100 legislators. Of course, there is no tie between the recipients of this largesse and their promotion of the vaccine, say beneficiaries like presidential candidate and current Texas governor Rick Perry. In 2007, Perry signed an executive decree mandating that all girls in Texas receive the vaccine. The $28,500 Perry received was minor compared to his other connection to Merck: Perry’s chief of staff, Mike Toomey, became a lobbyist for Merck, championing the HPV vaccine. Once in that position, [he] announced his plans to raise over $50 million for Perry’s presidential campaign.”

“Fortunately, some researchers don’t believe the hype. Dr. Diane Harper, one of the lead researchers in the development of the HPV vaccine, recently told the Kansas City Star, the vaccine for boys is ‘pie in the sky…We’re short of health care dollars. Why should we spend it on that?’

“Indeed. There are better ways to spend the billions of dollars currently being spent on HPV vaccines. First, we already have a pretty terrific way to prevent most cervical cancer deaths, and it’s called the Pap smear. Since poor women are less likely to get Pap smears and more likely to die from cervical cancer, we could start by extending medical services to them. Second, many oral cancers are caused by smoking, and men and women who smoke are more likely to die of oral and cervical cancer, so we could invest in smoking cessation efforts.”

How Effective Is the HPV Vaccine at Preventing Cancer? A Closer Look…

Jeanne Lenzzer, Discover Magazine, 2011:

“There are many, many instances in which researchers have promised cures and interventions that were expected to work based on eminently reasonable logic, but did not pan out. Take one recent recent example: bypass a clogged artery and you will prevent strokes (see Sharon Begley’s excellent blog post on “When Biology Refuses to Listen to Medical Logic”). And now comes one more eminently logical assumption: prevent cervical lesions from some strains of HPV in some people for some period of time, and you will save lives from cervical cancer overall. Unfortunately, while the two HPV vaccines on the market may decrease the serious illness and death from cervical cancer, no study has proved that at this point, since no study has been conducted long enough to observe the development of cervical cancer or cervical cancer deaths.

“Conclusive studies with the most important, clinically relevant end points should precede wide uptake of any intervention. The data currently rely on surrogate end points (markers of possible cancer) and are simply not conclusive. So we can’t truly say how effective the vaccine is.”