by Mike Andrew - SGN Staff writer

Scientists at Oak Crest Institute of Science in Pasadena say they have developed a subdermal implant that can deliver antiretroviral drugs. Their finding is published in the latest issue of Antimicrobial Agents and Chemotherapy.

The implant is said to be about the size of a matchstick, and can deliver a controlled and sustained release of anti-HIV drugs for up to 40 days with no adverse side effects. Tests have so far been done only with dogs, with human testing to follow.

'To our knowledge this is the first implant to be used for this purpose,' said Oak Crest founder and president Dr. Marc Baum.

'This novel device will revolutionize how we treat or prevent HIV/AIDS as it delivers powerful HIV-stopping drugs and eliminates one of the key obstacles in HIV/AIDS prevention - adherence to proper dosing regimens,' he added.

Although daily doses of antiretrovirals can help HIV-negative people to resist HIV infection - called pre-exposure prophylaxis, or PrEP therapy - adherence to the dosing regimen is problematic.

In fact, medical practitioners and scientists acknowledge that adherence is one of the main drawbacks in current HIV prevention and treatment strategies. An implant that automatically releases the correct dose of antiretrovirals could solve the problem.

'It's unfortunate, but patients do not always follow the dosing instructions as prescribed,' Baum said.

'In clinical trials erratic administration of drugs has led to highly variable efficacy outcomes. That's what peaked our interest in the possible use of a subdermal implant for the prevention of HIV.'

The use of subdermal implants for contraception began in the United States in 1993. A small flexible tube, measuring about 40mm in length, is inserted under the skin by a health care professional, typically the upper arm. After it is inserted it prevents pregnancy by releasing hormones that prevent ovaries from releasing eggs and by thickening cervical mucous.

'Our subdermal implant is used in the same manner as a contraceptive implant. It is easily inserted and removed and provides sustained release of the potent prodrug tenofovir alafenamide, which is roughly ten times more potent against HIV than tenofovir disoproxil fumarate, another tenofovir prodrug that has been shown to prevent sexually transmitted HIV when used as a pre-exposure prophylaxis,' Baum said.

'We are very pleased with the results of our preliminary studies and are working diligently to develop a subdermal implant for HIV prevention that will remain effective for a full 12 months.'

 Share on Facebook

Share on MySpace!

    Share on Delicious

Share on StumbleUpon!