More Safety Points for HPV Vaccine

Gardasil vaccine for HPV does not lead to autoimmune diseases after immunization

(RxWiki News) The vaccine recommended for boys and girls to prevent HPV, an infection that can cause cervical and other cancers, has been shown not to cause diabetes, lupus or similar diseases in young women.

A large safety study was conducted by Kaiser Permanente to look for any of 16 different autoimmune diseases, which are conditions where the body mistakenly attacks some part of itself that the immune system doesn't recognize.

"Vaccinate your children against HPV."

Chun Chao, PhD, a research scientist at the Kaiser Permanente Department of Research & Evaluation in Pasadena, Calif., led the study looking at the medical records of 189,629 females who got the vaccine between 2006 and 2008.

The recipients all lived in California and were between the ages of 9 and 26. Researchers followed them for six months after they received each of the three doses of Gardasil, an HPV vaccine licensed by the FDA in 2006 and manufactured by Merck & Co., which also funded this study.

Chao and his colleagues found that the girls and women vaccinated did not show an increase in any of the 16 diseases compared to a group of unvaccinated girls and women of similar size and characteristics.

The HPV vaccine is included on the vaccination schedule of the Centers for Disease Control to protect against several strains of human papillomavirus, the most common sexually transmitted infection in the US.

Besides Gardasil, another approved HPV vaccine called Cervarix is made by GlaxoSmithKline.

Although recommended for both girls and boys, some parents have withheld the vaccine from their children out of fear that it will cause other diseases.

This study shows that those fears of the vaccine causing other diseases are unfounded.

"This kind of safety information may help parents with vaccination decisions," Chao said.

"These findings offer some assurance that among a large and generalizable female population, no safety signal for autoimmune conditions was found following HPV4 vaccination in routine clinical use," he said.

In addition to lupus, rheumatoid arthritis, type 1 diabetes, multiple sclerosis, they looked for lesser known autoimmune diseases.

These included immune thrombocytopenia, autoimmune hemolytic anemia, Hashimoto's disease, Graves' disease, acute disseminated encephalomyelitis, other demyelinating diseases of the central nervous system, vaccine-associated demyelination, Guillain-Barré syndrome, neuromyelitis optica, optic neuritis and uveitis.

Although clinical trials have shown the vaccine's safety before it was licensed, population studies using large groups like these can sometimes reveal rarer side effects that did not appear in the trials.

The Vaccine Adverse Event Reporting System (VAERS) can also collect safety data following vaccinations, but its value is limited since no comparison groups exist for the cases reported and it can be difficult or impossible to determine if the vaccine actually caused the adverse event that's reported.

The Merck-funded study appears in the February issue of the Journal of Internal Medicine. Chao and several other study authors have received research funding from Merck, GlaxoSmithKline, Novartis, Wyeth (Pfizer) and Sanofi Pasteur, which all manufacture vaccines.

Merck did contribute to designing the study, reviewing the data and writing the paper. The study plan was approved by the FDA.

Review Date: 
January 27, 2012