Slow-Release HIV Drug Could Pave the Way for Weekly Dosing

Patients with HIV know that taking their antiretroviral therapy drugs is a daily ritual. Now, a slow-release capsule designed to deliver enough drugs for a week’s worth of HIV treatment in one dose has been developed by researchers at MIT and Brigham and Women’s Hospital.

While other long-acting treatments for HIV have been proposed, these usually rely on injecting antiretroviral drugs for sustained release. The current study still proposes an oral administration method, but has the same potential to improve patient adherence to their HIV medications by reducing pill burden.

According to the researchers, the once-weekly pill could also be used by individuals at risk of HIV infection as a prophylactic. They published the details of the slow-release capsule in the journal Nature Communications.

“One of the main barriers to treating and preventing HIV is adherence,” said Dr. Giovanni Traverso, a research affiliate at MIT’s Koch Institute for Integrative Cancer Research and a gastroenterologist and biomedical engineer at Brigham and Women’s Hospital. “The ability to make doses less frequent stands to improve adherence and make a significant impact at the patient level.”

Despite the effectiveness of antiretroviral drugs, HIV remains a major global health problem, with 2.1 million people newly-infected with the disease and 1.2 million HIV-related deaths in 2015 alone. Pill burden is one of the largest barriers to effective disease maintenance and is one of the major reasons why antiretroviral drugs are not being more widely used as preventive medicine.

The capsule is designed to be loaded with drugs and encased in an easy-to-swallow coating. Due to its star-shaped design, the capsule is capable of slowly releasing its drug payload as the arms of the star unfold.

In animal studies, the researchers found that the capsules were capable of lodging themselves in the gastrointestinal tract for one week. Once all of the drug payload has been released, the capsule coating itself is degraded and passed through the system.

“A longer-acting, less invasive oral formulation could be one important part of our future arsenal to stop the HIV/AIDS pandemic,” said Anthony Fauci, director of the National Institute of Allergy and Infectious Disease, which partly funded the research. “Substantial progress has been made to advance antiretroviral therapies, enabling a person living with HIV to achieve a nearly normal lifespan and reducing the risk of acquiring HIV. However, lack of adherence to once-daily therapeutics for infected individuals and pre-exposure prophylaxis (PrEP) for uninfected at-risk people remain a key challenge.

“New and improved tools for HIV treatment and prevention, along with wider implementation of novel and existing approaches, are needed to end the HIV pandemic as we know it,” continued Fauci. “Studies such as this help us move closer to achieving this goal.”

Traverso and his colleagues founded Lyndra, a biotech company focused on developing this extended-release drug encapsulation technology. The researchers hope to soon test the drug delivery system in a human clinical trial.

“We are all very excited about how this new drug-delivery system can potentially help patients with HIV/AIDS, as well as many other diseases,” said Robert Langer, the David H. Koch Institute Professor at MIT.