A novel pillbox in a capsule to allow weekly dosing for HIV drugs

In a breakthrough research, scientists at MIT and Brigham and Women’s Hospital have succeeded in developing a capsule that will allow a week’s dose of HIV medicines to be delivered in a single dose. This will substantially help HIV patients adhere to the strict dosing schedule required by the drug cocktail taken by them to fight against the infection.

The new capsule is designed in a way that it has to be only taken once a week, and the drug will be released gradually all week long. It will not only improve patient compliance to drug schedule, but will also help people at high risk of contracting the infection from getting infected.

According to researchers, one of the major challenges in treating and preventing HIV infection is adherence to dosing schedule, which can be improved by decreasing the dosing frequency.

This new capsule is being called ‘a pillbox in a capsule’ by the scientists at Lyndra, a company that was created to develop this technology. It is now working towards performing a clinical trial for this delivery system, which is speculated to benefit people with HIV infection and other chronic diseases.

Several clinical trials that have been carried out to determine if antiretrovirals can be used for preventing HIV infection in healthy population have shown mixed results. One of the major hurdles in this preventative treatment is the difficulty in getting people to stick to the dosing schedule. Researchers believe that the drug delivery capsule developed by them will help in alleviating this problem.

The novel capsule developed has a star-shape structure with six arms that is loaded with drugs, is folded inwards and has a smooth coating. After the capsule is swallowed, there is unfolding of the arms and a gradual unloading of the drugs.

Earlier, the entire star shape was made from a single polymer, which made it difficult to design new capsules that could release drugs at changeable rate. Therefore, a new version was conceptualized, which utilized a stronger polymer for making the star structure. Also, it was made possible to fill each arm with a different drug-loaded polymer; eventually, making it easy to design a capsule that could release drugs at different rates.

The capsule, when tested in pigs, showed positive results. It got lodged successfully in their stomach, and released three different HIV drugs over a week. After releasing the drug, the capsule disintegrated into smaller components that can then pass through the digestive tract.

Scientists have determined that changing a daily dose to a weekly dose improved the efficacy of prophylactic HIV treatment by nearly 20%, which when projected onto the South African population through a simulated computer program, estimated to save 200,000 to 800,000 lives in the next 20 years.

The team is currently working to optimize this technology to deliver other drugs used for treating other diseases. The study was additionally funded by Brigham and Women’s Hospital, National Institutes of Health, Bill and Melinda Gates Foundation and Global Good Fund.