HPV Roundup: Gardasil safety worries, Cervarix FDA delays, more on mandates

There's been a flurry of media coverage this week about possible safety issues related to Gardasil. It appears that the attention was initiated by this report released by Judicial Watch, the conservative watchdog group. Like its previous reports alleging numerous deaths and illnesses caused by vaccine, this Judicial Watch report is based on unconfirmed submissions to VAERS, the government's clearinghouse for reports of possible vaccine-related adverse events. Reports to VAERS -- widely described as a 'hypothesis-generating mechanism' -- are later examined by government officials to determine what, if any, role a vaccine may have had in the reported condition.

Numerous other outlets have raised questions about Gardasil's safety in the past few days, most notably this CBS News story by Sharyl Attkinson, the media member who is increasingly at the forefront of reporting on alleged vaccine risks. Other media outlets examining the topic include CNN and WebMD.

In the meantime, officials from CDC and FDA have assured the public that the vaccine remains safe and effective and that reports of possible adverse events will continue to be investigated. Merck responded similarly yesterday, noting the limitations of reports made to VAERS.

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Meanwhile, it appears that the U.S. head-to-head battle between Gardasil and GSK's Cervarix will most likely be delayed until late 2009. Last week, the Wall Street Journal and Reuters, among others, reported the GSK announcement of its timetable for submitting additional trial data requested by FDA. Here is the GSK press release. It notes that Cervarix is already approved in 67 countries, including the E.U., but it's no secret that the U.S. market is by far the most lucrative, as Merck's sales figures from earlier this year illustrated.

From a business standpoint, this is decidedly good news for Merck, as it extends its head start in the U.S. (The news has not all been good, however, as it was announced late last month that Merck's application to expand the indication for Gardasil for women through age 45 will face additional scrutiny and delays. Here's a story from Reuters and the Merck press release.)

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In other news, two papers have recently been published in academic journals on HPV mandates (joining a growing literature on this topic -- including papers by Schwartz, et al., Colgrove, and Zimmerman.) One paper, "Assessing Mandatory HPV Vaccination: Who Should Call the Shots?" (Javitt, et al.) appears in the Summer 2008 issue of the Journal of Law, Medicine & Ethics (subscription required). In short, the authors conclude, "...Mandating HPV vaccination at the present time would be premature and ill-advised."

Also, the May 2008 Harvard Law Review published a paper titled "Toward a 21st Century Jacobson v. Massachusetts (pdf), alluding to the 1905 case that is widely seen as the foundation for state public health powers. The authors argue that a distinction should be drawn between vaccines that are 'medically necessary' (such as smallpox) and those that are 'practically necessary' (such as hepatitis B and HPV, for which other preventive measures are available but not widely used). The paper suggests that current law and policy fail to acknowledge the implications of this distinction.

No evidence of RotaTeq-intussusception link observed

Students of contemporary vaccine history are likely familiar with the story of RotaShield, a vaccine against rotavirus licensed in 1998 but withdrawn a year later following the apparent correlation between it and intussusception, a potential life-threatening bowel obstruction.

The clinical testing of RotaTeq, the Merck vaccine licensed in 2006, showed no such link, yet alarms were raised by a 'public health notification' titled "Information on RotaTeq and Intussusception" issued by FDA in February 2007. Despite its title, the announcement did not suggest that intussusception rates among vaccinees were any greater than what could be expected in the general population.

This month's issue of Pediatrics examines the topic in much greater detail, in a paper from CDC and FDA researchers titled, "Postlicensure Monitoring of Intussusception After RotaTeq Vaccination in the United States, February 1, 2006, to September 25, 2007". Based primarily on VAERS reports, the study concludes that there is no association between RotaTeq and intussusception.

Information about general trends in intussusception rates -- independent of a connection to vaccines -- appeared in a paper in the May issue of Pediatrics: "Trends in Intussusception Hospitalizations Among US Infants, 1993–2004: Implications for Monitoring the Safety of the New Rotavirus Vaccination Program".

More on thimerosal...

With a headline sure to amaze those who don't read the full story, the MetroWest Daily News (part of the Boston Herald family) proclaims, "Study links autism, vaccine." If this were even the least bit true, one suspects the MetroWest Daily News wouldn't be the only media outlet covering the story.

Rather, the story here is in reference to a paper published in the Journal of American Physicians and Surgeons titled "Early Downward Trends in Neurodevelopmental Disorders Following Removal of Thimerosal-Containing Vaccines."

The story explains:

"Autism diagnoses have dropped nationwide since mercury was removed from most childhood vaccines, according to a new study that some say lends credence to charges that vaccinations were responsible for a huge increase in autism cases. "

The paper in questions uses state and federal databases that track autism prevalance as well as VAERS, the Vaccine Adverse Event Reporting System. All of these sources have significant data reliability concerns, which, to the newspaper's credit, are noted in the story.

For example, adverse events can be reported to VAERS by anyone and are not verified for accuracy. This paper in Pediatrics (subscription required) -- Goodman, M.J., and Nordin, J. "Vaccine Adverse Event Reporting Source: A Possible Source of Bias in Longitudinal Studies." Feb. 2006; 117: 387-390 -- finds that most thimerosal-related reports to VAERS were directly related to pending litigation. The authors specifically warn researchers attempting to use VAERS data for studies such as the one above about the serious questions regarding its reliability.