Researchers have developed a drug capsule that could allow people with HIV to take just one dose of antiretrovirals (ARVs) per week.

Publishing their findings in Nature Communications, researchers built on a previous study in which they had designed a capsule that could remain in the stomach for two weeks, gradually releasing a malaria medication.

The research team’s capsule is star-shaped and has six folded “arms” covered in a smooth coating and loaded with medication. Once the capsule is swallowed, the arms unfold and gradually release the medication.

For the new version of this capsule, designed for use with ARVs, the investigators constructed the backbone of the star structure out of a strong polymer. Each of the structure’s six arms can be filled with a different drug-loaded polymer to allow for the drugs to be released at different rates. Once the drugs are released, the capsule disintegrates into smaller parts that can pass through the digestive tract.

The scientists conducted experiments with pigs and found that the capsules successfully lodged in the stomach and then released a trio of ARVs over the course of one week.

To read a press release about the study, click here.