Given the recent events in New York and Washington DC, several conferences which were scheduled to take place in September and October have been postponed and are in the process of being rescheduled. These include the Interscience Conference on Antimicrobial Agents and Chemotherapy (ICCAC) and the Salvage Therapy Workshop. The ICAAC conference often yields new information on anti-HIV therapies and therapies to treat AIDS-related conditions and opportunistic infections. The Salvage Therapy Workshop focuses on new strategies for treatment among people who have experienced viral breakthrough or poor responses while on anti-HIV therapy and/or have developed multidrug resistance to many anti-HIV therapies. It is as yet unclear if the International Workshop focusing on lipodystrophy, scheduled to take place in October in Athens, will be delayed. Because information from these conferences were scheduled to be highlighted in Project Inform's journal, the PI Perspective, we will be delaying publication of the journal until January of 2002.
Barcelona Switch Study -- Early results from a Barcelona study show that people who switch treatment regimens every three months may have a better anti-HIV response compared to those who continue on the same regimen. About 160 people who had not previously taken anti-HIV therapy participated in this study.
Volunteers received A] d4T+ddI+efavirenz (Sustiva), B] AZT+3TC+nelfinavir (Viracept) or C] alternated between the two regimens every three months. Those on regimen A who experienced a rebound in viral load (HIV RNA levels) would then receive regimen B, and vice versa. Participants on regimen C could switch to a new regimen based on resistance test results.
Results after 48 weeks show that about 70% of people using regimen C had viral loads below 400 copies/mL compared to about 60% for those on regimen A or B. There was no difference in increased number of CD4+ cells among the three groups -- an average of about 70 cells after 48 weeks. All participants who were over 95% adherent to their medications responded equally well, regardless of the regimen.
One interesting observation was that those on regimen C reported less severe and more manageable side effects the second time they used the alternate regimen. For example, the neurological side effects of efavirenz were less severe the second time around. The researchers believe this is due to the participants knowing what to expect and working out ways to deal with the side effects from the first time they were on the regimen.
US Military Efavirenz Study -- Results from a US military study suggest that African Americans may not respond to efavirenz as well as Caucasians. The study enrolled 56 African Americans and 43 Caucasians and included as a comparator another 274 people who were taking either indinavir or nelfinavir for the first time.
The study looked at the time to failure, which for this study was defined as either an increase in viral load to over 1,000 copies/mL HIV RNA for people who were able to achieve undetectable viral loads or failure to go below 1,000 copies/mL by week 16. The median time to failure among African Americans was 440 days. However, at the time of the analysis, the median time to failure among Caucasians still had not been reached after 1,400 days. In comparison, there was no difference in time to failure between African Americans and Caucasians taking either indinavir or nelfinavir.
The study's researchers initially thought that the reason for this discrepancy was because African Americans broke down (metabolized) efavirenz more rapidly and, as a result, there would be lower levels of the drug in blood. However, early results suggest that efavirenz levels were comparable between the two groups. The researchers are looking into other reasons to explain these findings.
Dupont Pharmaceuticals, the developers of efavirenz, have re-analyzed the results from the Dupont 006 study, a study with 450 participants. In that study they found no difference in response between African Americans and Caucasians. Additionally, several researchers/clinicians at the workshop said that they have not seen a difference in response based on race in their practice.