ATLANTA, Ga – The challenges the quest for an HIV cure faces include the failure of every strategy so far, dissension surrounding patient selection for trials, and a reservoir of HIV virus that will only dissipate of its own accord over a 70-year period in most HIV-infected individuals, Dr. Robert Murphy from Northwestern University said at a session here Tuesday.
While the technology necessary to evaluate the size of the HIV reservoir in HIV patients is costly, complex and generally not available in Africa, Dr. Murphy argued that simple adaptive clinical trials can and will move forward on the continent most affected by the pandemic. Sophisticated viral load measurement may be absent, but willing patients, capable clinics and basic viral load measurement are all available in most places, he said.
Citing a robust research infrastructure created by the National Institute of Allergies and Infectious Diseases that includes trial networks and laboratories, and years of experience with HIV clinical trials, Murphy outlined a scenario for conducting a cure trial in Mali to potentially test one or more of the three dozen drugs in the cure pipeline now, some new compounds and repurposed drugs. “What matters”, he said, “is what happens when you stop antiretroviral therapy.”
Such trials could enroll small numbers of patients, under 50 participants, and would be aimed at trying various interventions from drugs to boost the immune system, drugs to draw HIV virus cells out of latency so they can be eliminated, and/or drugs to specifically boost the immune response to HIV, with the aim of providing early signals about the their potential benefit. To avoid compromising patients’ health, Dr. Murphy said, antiretroviral therapy would be interrupted only until their virus rebounded up to 1,000 copies of virus per milliliter of blood. The best patient candidates for such an adaptive trial would be individuals with high immune cell counts who have their virus suppressed on treatment, and individuals under 60 years old.
The selection of what interventions to try will likely be based on what is available, he said. The biggest challenges are likely to surround getting competing companies to contribute their products to the same trial, and getting experimental compounds into African countries.