Report 7 -  4th International Workshop on HIV Drug Resistance and Treatment Strategies
Written by Jules Levin
Sitges, Spain, June 12-16 2000

PMPA: A more Simple Explanation

PMPA is a nucleotide RT inhibitor in development for treating HIV. Several studies have already been conducted in humans and in laboratory experiments. The following information is based on the studies so far conducted. But further studies are needed to confirm what we so far have seen. PMPA will be most effective for individuals who have never been treated. In a small 28 day monotherapy study of untreated individuals researchers  saw a 1.5 log reduction in HIV viral load. But it appears as though PMPA will also be effective for individuals with prior NRTI experience. The effectiveness of PMPA in individuals with NRTI experience will likely vary according to the amount of experience and resistance to NRTIs they already have. It looks like 3TC experience and having the 3TC resistance mutation (M184V) will improve the effectiveness of PMPA. Many people who have had AZT, d4T or ddI have also had 3TC so they should also have the 3TC mutation, if they have detectable virus or if they have drug resistance. It appears that for a person with extensive NRTI experience who will try PMPA they will may to include 3TC in the new regimen to retain the presence of the M184V mutation.