Long acting parenteral (LAP) antiretrovirals (ARVs) are in development for both the treatment and prevention of HIV. It is estimated that the first LAP ARV could be available (most likely as PrEP) within five years. It is reported that combination ARVs that can be used as complete treatment regimens will take significantly longer to complete research and development and to be made available for use.
There may be several advantages to utilizing LAP ARVs. Advantages to long acting ARV’s being used as treatment include:
- Improved adherence
- Reduced drug interactions
- Reduced toxicities
- Possible lower costs
Used as PrEP, adherence would predictably increase with a weekly or monthly injection in compassion to daily oral administration. Cost may also be lowered significantly. LAP ARVs can be administered either orally, via subcutaneous injection or inter-muscular injections. Administration may take place once a week, every two weeks, once a month or even less frequent.
LAPARVs in development include:
- Ibalizuab (monoclonol antibody) as an entry inhibitor for drug resistant HIV. Research suggests Ibalizumab may be effective as a once a month long- acting ARV.
- Gsk1265744 also known as GSK 744 is an integrase inhibitor. Analysis of 8 studies involving 245 people who were studied using oral or injected GSK744 shows it is well tolerated with few lab abnormalities.
- TMC278 (Rilpivirine), an integrase inhibitor, showed full protective benefit in macaque as LAP PrEP following rectal exposure.
- TMC278 in combination with GK1265744 is being studied in a phase I clinical trial in HIV negative individuals. The two drugs will be given through various interventions (IM, subq and oral) in a randomized, open label study to investigate the safety, tolerability and pharmacokinetics of repeat dose administration of the two drugs over a period of four months.