from Jules Levin

Geneva, Friday July 3

It is my understanding that the concept of induction/maintenance is used in cancer therapy. Initial therapy consists of a more potent regimen followed by a less potent and less complicated regimen. Several studies in HIV have been implemented in the last year with discouraging results. The rate of viral load rebound after maintenance therapy is introduced has been unacceptable. This doesn’t mean the concept will not be proven useful under certain circumstances. But, the correct circumstances have yet to be indentified. In induction/maintenance the hope is that the initial regimen will reduce HIV enough and possibly stimulate an immune response adequate to continue control of virus at the same level with a reduced maintenance regimem as was observed with the more potent induction regimen.

In this Late Breaker report the results of the ADAM study were presented by a Netherlands group. A more detailed report will be composed when I return to NYC. In this study participants received nelfinavir+saquinavir+d4T/3TC (4 drugs, 2 proteases). At baseline viral load was about 30,000 copies/ml. 88% achieved <50 copies/ml. I will have to double check this figure because it sounds impressive. Individuals were only randomized to one of two maintenance regimens if their viral load were <50 copies/ml on two consecutive weekly tests. After 36 weeks 9/14 had their viral load rebound and 5/14 still remained at <50 copies/ml. Of course, this data is not encouraging. The interesting data to me was that the slope of viral load decay was greater for the 5 responders than for the 9 non-responders. For me, this raises the question--if you follow a person’s rate or slope of viral load decay in the initial time period following the initiation of therapy, can you successfully inject a maintenance therapy if the slope was great enough?? I think this question should be considered for a clinical study.