The quadrivalent HPV vaccine was safe and immunogenic among women aged 13 to 45 years with HIV, according to data published in Clinical Infectious Diseases. There was lower seroconversion among women with higher viral loads and/or lower CD4 counts.
“HIV-infected women carry a disproportionate burden of HPV-associated diseases,” Erna Milunka Kojic, MD, associate professor of medicine at Brown University, told Infectious Disease News. “Many have already been exposed to HPV infection and overall vaccine responses can be diminished with higher degrees of immunosuppression. Only 4% of the women in this cohort had been exposed to all four HPV types in the vaccine as measured by serum antibody titers, so the vast majority of HIV-infected women would likely benefit from receiving the vaccine.”
Erna Milunka Kojic
In the AIDS Clinical Trials Group (ACTG) Protocol 5240, the quadrivalent HPV vaccine (Gardasil, Merck) was evaluated among 319 participants. There were three strata, defined by CD4 count. In stratum A, patients (n=130) had a CD4 count of more than 350 cells/mm3; in stratum B, patients (n=95) had a cell count of 200 cells/mm3to 350 cells/mm3; and in stratum C, patients (n=94) had a cell count of less than 200 cells/mm3.
The researchers measured seroconversion proportions for HPV types 6, 11, 16 and 18 at 28 weeks among women in each stratum. The seroconversion proportions were as follows:
- HPV type 6: 96% in stratum A, 100% in stratum B and 84% in stratum C.
- HPV type 11: 98% in stratum A, 98% in stratum B and 92% in stratum C.
- HPV type 16: 99% in stratum A, 98% in stratum B and 93% in stratum C.
- HPV type 18: 91% in stratum A, 85% in stratum B and 75% in stratum C.
In a generalized estimating equations (GEE) model, the odds of seroconversion for HPV types 6, 11 and 16 were higher compared with HPV type 18. In addition, the GEE model also showed that CD4 counts lower than 200 cells/mm3 and HIV viral loads higher than 10,000 copies/mL were associated with lower seroconversion.
“The take-home message is that the quadrivalent HPV vaccine is immunogenic and safe among these women, even those with low CD4 counts and prior HPV exposure,” Kojic said. “Our hope is that these data will encourage providers to vaccinate HIV-infected women to prevent HPV-associated cancers and lesions among women that carry a high burden of HPV-related diseases.
Kojic said that future related research questions include the duration of antibody titers for the four different HPV types and the timing of vaccine boosters. In addition, efficacy studies of the vaccine have not been done in women with HIV. — by Emily Shafer
Disclosure: The researchers report no relevant financial disclosures.