Findings of the Phase 11a Proof of Concept Study for Second generation maturation inhibitor 176 was presented today. The mechanism of action of this drug is it stops the last step of protease cleavage during maturation. In vitro it showed better results than the first generation maturation inhibitors. 10 day monotherapy showed potent antiviral activity for both subtype B and C and it was generally well tolerated. There were no serious adverse events or discontinuations due to adverse events. A phase 11b global study is underway and looks promising. However in vitro resistance data is still being analysed.
A population pharmacokinetic model for a long acting injectable nanosuspension of Rilpivirine for IM injection was presented. The model was used to describe the absorption and disposition of RPV after IMI. The simulations were used to select different dosing regimens for further clinical evaluation. A cohort study showed that 73% of people wanted to use a long acting formulation. Long acting formulations are Cabotegravir 800mg 3 monthly and Rilpivirine 1200mg monthly. Phase 2 trials are underway. However with long acting formulations the risk is that if they miss a dose they can have prolonged periods of low drug levels posing a risk for resistance. They are more likely to be given to people who are less adherent in the first place. However it could be useful in adolescents who may find it harder to take a daily pill.