Immunogenicity to Human Papillomavirus Vaccine (Gardasil) Among IBD Patients on Immunosuppressive Therapy

Many IBD patients take immunosuppressive agents and we are uncertain as to their capacity to mount a truly protective response after vaccination. If IBD patients do not have an adequate immunological response, they may need to increase the dosage or get booster shots. Many clinicians who treat patients with autoimmune diseases are asking if the vaccine is safe and effective. Thus, this study has important clinical and public health significance because more than one million people in the United States have been diagnosed with IBD.

There is not much studied about HPV and immunocompromised patients. Research on healthy women who were immunized with a set of three HPV vaccines demonstrated significantly increased antibody titers. In addition, they had significantly reduced HPV incident and persistent infection and HPV-related disease (cervical, vulvar, and vaginal cancers, cervical intraepithelial neoplasia, genital warts) through five years of follow-up compared to controls who received a placebo. The HPV vaccine was well tolerated without significant side effects.

The aims of this research are to measure the immune response in 9-26 year old IBD patients who are on immunosuppressive agents after receiving the HPV vaccine compared with historical controls. We will also evaluate the number and type of vaccine-associated adverse events as well as the disease activity and flare-ups that occur after each dose of vaccine. We hypothesize that IBD patients on immunosuppressive therapy will have have a similar immune response to HPV types 6, 11, 16 and 18 at one month postdose 3 compared to healthy age-matched historical controls.

The patient population includes IBD patients who are on immunosuppressive medications. Recruiting approximately 100 patients will provide adequate power for the study. A blood sample will be taken from all IBD patients to evaluate baseline antibody levels and markers (e.g., ESR, CBC, albumin) before or immediately after immunization with the HPV vaccine. Lab tests will be redrawn at 7 months to evaluate the level of antibody titers and follow the markers. During the study, we will track basic laboratory measures, disease status by using the Pediatric Crohn's Disease Active Index or Harvey-Bradshaw Index for UC, side effects from the vaccinations, and other adverse events.