S.A.N.E. Vax calls for temporary withdrawal of Merck & Co's Gardasil claiming inappropriate endpoint and unreliable HPV genotyping methods used

In a letter addressed to US Food and Drug Administration Commissioner Margaret Hamburg, Norma Erickson, president of the not-for-profit S.A.N.E. Vax group, stated her research team has revealed the fact that, in November 2001, the VRBPAC (Vaccines and Related Biological Products Advisory Committee) mistakenly allowed Merck & Co (NYSE: MRK) to use “CIN 2/3, AIS, or cervical cancer; ie, CIN 2/3 or worse by histology - with virology to determine the associated HPV type - as the primary endpoint in the evaluation of its vaccine [Gardasil] to prevent cervical cancer.”

As this story was published, there was no response to The Pharma Letter’s request for a comment from Merck on the situation.

In her letter, Ms Erickson pointed out that in the natural history of cervical cancer development only a small fraction of the CIN 2 lesions will progress to CIN 3 lesions; and only a small fraction of CIN 3 lesions will progress to cervical cancer. Therefore, there are many more CIN 2 lesions than CIN3 lesions and cervical cancers combined in any female population, including the subjects enrolled in the Gardasil clinical trials. As a result, the overwhelming majority of the “CIN 2/3 or worse” cases used for evaluation of efficacy and listed in the VRBPAC Background Document on Gardasil HPV Quadrivalent Vaccine presented at the May 18, 2006 VRBPAC Meeting must have been CIN 2 lesions.