Technology Against AIDS: Device Could Anti-HIV Drugs
A new device that is taken (to self-install) orally once a week in a capsule could dose two or three antiretroviral drugs and significantly reduce the risk of dose loss or the risk of developing drug resistance, according to with the research published today in Natureze Magazine.
Researchers describe their device as a 'mini-pillbox' the size of a normal compressed capsule but which contains a star-shaped structure that can dispense the drug for up to seven days. The star prevents the small device from passing from the stomach to the small intestine until the drugs have been dispensed, at which point the device breaks down and passes into the intestine. The small device does not prevent the passage of food through the digestive system.
The mini-pillbox can offer up to six formulations (one per arm), but it can only be used once a week when the daily dosage is 50mg or less. The researchers used cabotegravir, dolutegravir and integrase inhibitors and the non-rilpivirine reverse transcriptase inhibitor to test the device in swine. The drugs were loaded into polymer matrices that released the drugs slowly over the course of a week.
The pilot study showed that the concentrations of each drug remained high, and in the case of rilpivirine at levels corresponding to the daily peak dosage for at least one week. The rate at which drugs were released could be altered through a different polymer to keep the drug in place.
Technology Against AIDS also brings disadvantages
A disadvantage is that the method is only suitable for drugs that are stable in gastric acid. Use of tenofovir alafenamide (TAF) had to be abandoned because only ten percent of the drug remained in a stable form, which can be metabolized after 10 hours of exposure to gastric acid.
The device is designed to overcome difficulties of slow release oral dosage formulations. For people who do not want to receive a long-lasting formulation of action intramuscularly, once a week the pill could be very attractive.
ViiV Healthcare is developing the combination of cabotegravir and rilpivirine as a long-acting action formula to be performed every two months, subcutaneously.
The device would also be suitable for delivering medications for pre-exposure prophylaxis (PrEP), say study researchers. They modeled the potential impact of mini-pillbox when used to provide therapy in PrEP. Assuming a similar level of efficacy for the drugs used in the device as for tenofovir, they estimated that weekly PrEP would improve the efficacy of PrEP by 20% compared to the daily preparation because of better adherence.
The research was partially funded by the Bill and Melinda Gates Foundation and the United States, the National Institutes of Health.
Tradduced by Cláudio Souza in 13 / 01 / 2018 from the original in New 'mini-pillbox' could deliver three HIV drugs in a single once-weekly dose written by Keith Alcorn at 09 / 01 / 2018.
Reviewed by Mara Macedo
Kirtane A et al. Development of an oral once-weekly drug delivery system for HIV antiretroviral therapy. Nature Communications 9 (2) 1-12, 2018.