VACCINE VALIDITY

In this week’s New England Journal of Medicine the results of a trial for a quadrivalent (covers 4 strains of the virus) vaccine for HPV (human papilloma virus) were released. HPV has been shown to cause cancer of the cervix. About 70% of the cases are caused by strains HPV-16 and HPV-18. The vaccine works on four strains – HPV-6/11/16/18. “Conclusion: In young women who had not been previously infected with HPV-16 or HPV-18 those in the vaccine group had significantly lower occurrence of high-grade cervical intraepithelial neoplasia related to HPV-16 or HPV-18 than the placebo group.”

Does this mean that the vaccine should be mandatory law for eligible young females? What about the young males that may harbor this cancer causing virus? The article states in the second sentence that Pap smear tests have “led to a significant decline in mortality from cervical cancer in developed countries, such programs are costly and have not been effectively implemented in most developing countries”. It is hard to believe this new vaccine by Merck will cost less than a Pap smear, or that it will be covered by insurances like the Pap smear. Furthermore it only covers 4 strains of HPV. What about the other strains? Is it still possible to get the cancer if the vaccine is taken? Makes you go hmmmm. The article states that “the quadrivalent vaccine is prophylactic, not therapeutic.”

Though the vaccine was found to reduce cancer of the cervix, it still occurred in some who had gotten the vaccine. It occurred more in those who did not receive it. One case was found to be from another strain, HPV-52. At the beginning of the study about 11% in the placebo group (did not receive vaccine), and about 11% in the vaccinated group had abnormal Pap smears. It is unclear if these were the same ones that developed cancer. Since the vaccine does not cover all strains, but reduces the overall number of cancer cases, should it be mandatory for young teens? Has there really been enough research to warrant this?

Side effects? The primary side effect reported was due to pain at the injection site. There were other side effects reported. This is mentioned in the article, but there is a separate supplement that documents these. In the supplementary appendix the most common were “gastrointestinal disorders”, “infections and infestations” and “general disorders and administration site conditions”. Others included “injury, poisoning and procedural complications”, “musculoskeletal and connective tissue disorders”, “immune system disorders”, and more. “Nervous system disorders” were the leading system side effect. The specific details of these conditions were omitted. The article itself mentioned neck pain and seasonal allergies. It seems the information from the supplement should have been front and center. Hmmm.

The clincher is that some women became pregnant during the study. They had already received the vaccine. Pregnancy complications and congenital defects in the babies were reported in the supplementary appendix.

Ironically, the last page of this supplement to the article was a chart for Pap smear management. The chart showed what to do for abnormal Pap smears, a “mandatory regimen for triage of abnormal Papaniclaou (long word for Pap) tests to colposcopic exam.” Colposcopic exam, colposcopy, is a test to check for cancer. It seems that Pap tests are still reliable, safer, and more cost effective.

This article, the supplement, and tables were hard to decipher. This is how I interpreted the results after reading it several times. It would be interesting to know how many doctors will pass all this information along to their patients of whom this will be required. After full disclosure, it should be up to the patient (and her parents) – Pap smear to check for early cancer or HPV vaccine to possibly prevent cancer. Hmmm.

Vaccine validity or more drug deception?