It may seem counterintuitive, but the injured brain can heal itself too much, medically known as maladaptive neuroplasticity.Imagine now if your brain had a built-in safety switch that prevented this. Scientists have discovered that’s exactly what happens with a protein called CCR5 – a cellular receptor that acts like a biological brake and the loss of which can result in memory loss and impairing recovery after brain trauma.

Maraviroc is a prescription antiretroviral medication originally developed to treat HIV by blocking the virus from entering cells through this same CCR5 receptor. Specifically, the drug works by preventing certain HIV strains from infecting immune cells when used alongside other HIV medications.

As an HIV drug, it was already known to improve neurocognitive functioning. The medication enhances the brain’s natural ability to repair and rewire itself, a capability that would also be greatly impactful for those with brain injuries. In fact, research into TBI and CCR5 on the NIH site shows that studies have spanned nearly a decade, with promising results. For example, multiple studies have shown that “maraviroc blocked CCR5 in mice and boosted the animals’ recovery from traumatic brain injury and stroke.” Dr. S. Thomas Carmichael at UCLA remarked about this connection, stating “this is the first time that a human gene has been linked to a better recovery from stroke.”

Real-world impacts of this treatment are emerging. The story of Debra McVean, featured in a New York Times article on September 4, 2025, documents how she participated in a clinical trial of maraviroc after suffering a stroke that paralyzed her left side. A month later, her neurocognitive skills had healed to the point that she could initiate movement in her fingers.