HIV-Positive women respond well to the human papillomavirus (HPV) vaccine, even when they have a low CD4 count, The New York Times reports. The AIDS Clinical Trials Group Protocol 5240 study investigated the safety of and immune system response to the vaccine Gardasil in 315 women with HIV who were between ages 13 and 45 and living in the United States, Brazil and South Africa. The researchers published their findings in Clinical Infectious Diseases.

The women were dived into three groups according to their CD4 count: Group A had counts above 350, group B between 200 and 350 and group C below 200.

After following the women for 28 weeks, the investigators found that they developed a protective immune response to each of the four strains of HPV against which Gardasil protects at a rate exceeding 70 percent, which was the preset benchmark for success. Those in group A developed antibodies against HPV types 6, 11, 16 and 18 in a respective 96 percent, 98 percent, 99 percent and 91 percent of participants. Those in group B had respective response rates of 100 percent, 98 percent, 98 percent and 85 percent. And those in group C had respective response rates of 84 percent, 92 percent, 93 percent and 75 percent.

While those with lower CD4s did respond less well to Gardasil, the researchers concluded that the vaccine would still be worthwhile for them. Furthermore, while some of the women had already been exposed to at least one of the four strains of HPV included in the vaccine’s realm of protection, only 4 percent had been exposed to all four. Consequently, there is likely still a benefit to vaccinating older, sexually active women living with HIV.

The study did not measure the vaccine’s efficacy in preventing cancer. The vaccine did, however, prove safe.

To read a release on the study, click here.

To read the study abstract, click here.

To read the Times story, click here.