HIV Viral Loads Drop in Drug Resistant Patients Using T-20, Studies Find
In what may be the "most exciting advance in AIDS treatment in years," researchers at the International AIDS Conference in Barcelona, Spain, today presented two positive studies on T-20, the first of a new class of drugs called fusion inhibitors that seek to block HIV before it invades a cell, the Wall Street Journal reports (Fuhrmans, Wall Street Journal, 7/8). The drug was specifically designed for patients who have developed resistance or intolerance to standard antiretroviral treatment (Kaiser Daily HIV/AIDS Report, 5/28). In the first study of two groups of 500 patients, between 28% and 37% of the patients who took T-20 in combination with other antiretroviral drugs reduced their viral load to below detectable levels. By comparison, 14% to 16% of the group that received only standard antiretroviral treatment experienced a similar decrease in viral load (Ingham, Agence France-Presse, 7/8). The second study also indicated that those taking T-20 experienced a comparable decline in viral load compared to those not taking the drug, 28% to 14% respectively, the Los Angeles Times reports (Maugh, Los Angeles Times, 7/8). Jacob Lalezair, director of Quest Clinical Research, which conducted one of the studies, said he had seen "a spectacular, I would hate to say it, miraculous recovery" among patients taking T-20 (Agence France-Presse, 7/8).
Treatment Implications
The research is considered "quite powerful" because the study was conducted "among heavily treatment-experienced patients" who have limited treatment options, according to Lalezari (Los Angeles Times, 7/8). Instead of becoming a first-line treatment, T-20 is expected to be used in patients who no longer respond to other treatments. As drug resistance increases -- 20% of newly diagnosed patients are infected with drug-resistant strains of HIV -- use of T-20 is expected to become more prevalent, the Journal reports (Wall Street Journal, 7/8). Like other HIV treatments, T-20 has shown signs that its efficacy will cease in patients after the virus becomes immune to the treatment by mutating (LaMendola, South Florida
Sun-Sentinel, 7/6). In addition, because the drug is a protein, it must be given via injections twice a day. Based on the results from the two studies, Trimeris Inc., which developed the drug, and Hoffmann-La Roche Inc., which will market the treatment, hope to win FDA approval for
T-20 by the end of the year (Los Angeles Times, 7/8). If approved, access to the drug may prove difficult due to the expected cost, which analysts say may be as high as $15,000 a year (Wall Street Journal, 7/8).