Intradermal Versus Intramuscular Polio Vaccine Booster in HIV-Infected Subjects

Overview

The purpose of this study is to determine whether a lower dose of inactivated polio vaccine (IPV) injected into the skin (intradermal administration) can work equally well or better than the standard dose injected into the muscle (intramuscular administration). There are more immune cells in the skin than in the muscle, and other vaccines have been shown to require a lower dose when administered intradermally. The study is being done in participants infected with HIV because HIV-infected people are known to respond less well to vaccines than other groups, so it is particularly important to know if IPV might work better in HIV-infected people if administered intradermally. If it is possible to lower the dose of IPV by intradermal administration, this would make inactivated polio vaccine more affordable in the developing countries where it is most needed

Oral polio vaccine (OPV) will not be sufficient to eradicate polio. OPV has failed to provide adequate polio immunity in certain immunocompromised populations, such as people with AIDS. Also, OPV can mutate and form neurovirulent strains capable of causing polio outbreaks. Inactivated polio vaccine (IPV), which cannot mutate into neurovirulent strains and which is more effective in populations that have failed to respond to OPV, will be needed globally to eradicate polio, but it is unaffordable for many developing countries. Because there are more immune cells in the skin than in the muscle, intradermal administration of IPV may be a way to increase the efficacy and reduce the dose (and thus the cost) of IPV. We plan to conduct a clinical trial randomizing 231 HIV-infected adults to receive a booster of two-fifths dose intradermal IPV, one-fifth dose intradermal IPV, full dose intramuscular IPV, or two-fifths dose intramuscular IPV. We will measure polio immunity before and after vaccine administration. Through this study, we will determine the optimal booster dose of intradermal IPV, whether intradermal works better than intramuscular IPV administration, and whether intradermal IPV is effective in an immunocompromised population. The data from this trial could contribute to global polio eradication.