Following treatment with a long-lasting drug delivery system and CRISPR-Cas9 based gene editing technology, HIV could not be detected in a subset of infected mice, according to a study published in Nature Communications. Of a total of 13 mice to receive the combination treatment in two separate trials, five showed no sign of HIV infection for up to five weeks after treatment. In contrast, HIV could be readily detected in mice that had received either treatment separately.

Currently, treatment for HIV-infected patients relies on a combination of antiviral drugs. However, this treatment is not a cure and the medication has to be taken throughout life.

Howard Gendelman, Kamel Khalili and colleagues developed a combination treatment for HIV to target the virus in a group of infected mice. The combination treatment relies on an antiviral drug formulation that releases the drug slowly and inhibits viral activity for several days, and CRISPR-Cas9 technology that removes the viral genetic code from infected cells by cutting out relevant pieces of DNA. Sequential treatment led to undetectable levels of HIV in approximately one-third of the mice. They studied the mice using a number of different techniques, and found that HIV could not be detected in infectious cell and tissue sites in these mice for five weeks after the treatment.

Although the results with mice are promising, the authors plan further studies to improve the delivery of agents to viral reservoirs and specifically eliminate latent viral infections.