Wednesday, December 29, 2010

Gardasil: Merck presents more flawed data - FDA grants extended use

The FDA continues to spark controversy over Merck's Gardasil vaccine, as they ignore scientific principles to grant approval for extended use as a preventative for anal cancer and anal intraepithelial neoplasm. The SaneVax Team wants to know why.

Wednesday, December 22, 2010, Merck announced the FDA had granted permission for Gardasil to be used in the prevention of anal cancer in the male and female population, ages 9 through 26.

The SaneVax team finds this situation appalling, to say the least. After having studied the information Merck presented to the FDA Vaccines and Related Biologics Committee (VRBPAC) to secure this extended use, we cannot sit idly by and let medical consumers around the world accept these ‘facts’ at face value.

First, let it be said that any Advisory Committee Open Meetings to review applications for extended use are supposed to be public. The FDA has yet to publish the minutes from the meeting where they agreed to expand Gardasil’s use to include AIN and anal cancer.

Second, medical consumers need to know the real threat anal cancer presents. According to the National Cancer Institute, an estimated 5,260 people will be diagnosed with anal cancer in 2010 (United States). 720 fatalities due to anal cancer are anticipated. The average age at diagnosis is 60. The data presented in a 1996 study indicates you are over 10 times more likely to die from an overdose of over-the-counter pain medications, such as aspirin, than you are to die of anal cancer. Merck made no mention of these facts anywhere in the documentation they presented to the FDA.
SaneVax wants to know, “In what universe does this make a convincing argument for vaccinating people ages 9 to 26?”

In addition, Merck once again blatantly chose a double standard to set the endpoints for efficacy analysis to suit different purposes within the same document. On one hand, they quoted the authoritative National Cancer Institute (NCI) opinion that high-grade AIN 2/3 is a premalignant lesion in order to justify using reversible and poorly defined precancerous histological changes as the endpoint for evaluating Gardasil’s potential to prevent anal cancer.

On the other hand, when it came to ‘judging’ the real efficacy of Gardasil against premalignant lesions, they suddenly switched to using AIN of any grade, not necessarily high grade 2/3, as the determining factor. This is a gross deception because, as Merck should have known, AIN grade 1, and grade 2, lesions are frequently self-reversing and do not lead to cancer at all.
Furthermore, Merck stated HPV infection is the key in pathogenesis of anal cancer. In their selection of MSM (males who have sex with males) study subjects, Merck emphasized that key exclusion criteria included a history of HPV-related disease or infection. However, potential subjects were only examined for ‘visible signs’ of HPV infection; not screened via PCR, or tested for seropositivity prior to enrollment.

On the other hand, under Disease Endpoint Adjudication, it was required that at least one of HPV types 6, 11, 16 or 18 detected be confirmed by Thinsection PCR. Since no PCR testing was performed at the time of enrollment, a high percentage of study subjects already infected with HPV, but without ‘visible signs,’ might have been assigned to the placebo group, thus giving the vaccine group an artificially high appearance of efficacy. Since there was no PCR-based common denominator established at the outset of the clinical trial, efficacy results based on PCR endpoint analysis should not be accepted as valid.

For confirmation of type-specific HPV infections during the trials, Merck did not use an FDA-approved genotyping method, or, the reliable HPV DNA short target sequences genotyping recommended by the NCI. Because of this choice, no one knows how many subjects began the trials with prior exposure to vaccine-relevant HPV; nor does anyone know for sure how many subjects were infected by any vaccine-relevant HPV at the end of the trials.
One additional problem is HPV types 6 and 11 are classified as low risk, meaning they are not normally associated with any type of cancer. Even so, Merck included 19 cases of AIN related to these two low-risk HPV genotypes to demonstrate the ‘efficacy’ of Gardasil against anal cancer.

SaneVax believes perhaps it is time the FDA stop claiming they are a “science-based, science-driven regulatory agency responsible for the safety, efficacy and security of drugs and medical devices.”
When it comes to the safety, efficacy and security of FDA approved vaccines medical consumers are apparently on their own.

Sources:
http://sanevax.org/pdf/VRBPAC-gardasil-2010-anal-cancer.pdf
http://www.cancer.gov/cancertopics/types/anal
http://drugwarfacts.org/cms/?q=node/30
http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocuments/ucm181509.htm

For more information, go to http://sanevax.org/

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