Patients on mega-HAART salvage therapy survive just as long as those just starting their first HAART regimen, according to a Canadian study published in latest issue of The Journal of Infectious Diseases.
Although mega-HAART (also known as giga-HAART or multiple-drug rescue therapy [MDRT]) is controversial, since it often involves more than double the usual antiretrovirals used in HAART and requires a huge amount of motivation from those on it due to adherence and side-effect issues, this latest study provides real evidence that until something better comes along, mega-HAART means survival, at least in the short-term.
Investigators at the BC Centre For Excellence at St. Paul's Hospital in downtown Vancouver, BC, compared 341 HAART-experienced patients who began mega-HAART between August 1997 and 31 July 2000 with 1047 HAART-naive patients who began their first HAART therapy during the same period, and followed them for an average of three years.
The HAART-experienced patients had been on at least two prior triple HAART regimens and had had two consecutive viral load rebounds above 400 copies/mL after previously achieving an undetectable viral load. They had taken an average of seven different antiretrovirals prior to mega-HAART, and 36% of them had taken drugs from (and were resistant to) all three classes. The mega-HAART therapy was chosen based on individual patient history and preference, as well genotype resistance testing, and consisted of an average of six antiretrovirals from all three classes. Hydroxyurea was also used in two-thirds of cases.
The study found that although whilst on therapy the patients on mega-HAART had, on average, lower CD4 counts (230 vs. 390 cells/mm3) and slightly higher viral loads (112 vs.104 copies/mL) the death rate was not statistically different after three years (14.2% vs 10.9%; p = 0.105). Put another way, those patients on mega-HAART had only a slightly higher relative risk (1.17) of dying over three years than those on their first HAART regimen.
This is likely explained by the fact that mega-HAART was able to keep viral load suppressed and CD4 counts up above 200 cells/mm3, the threshold of severe immune suppression. The authors found that adherence was good, there was no unexpected toxicity and the overall dropout rate was low.
Although this is by no means an ideal solution to the increasing amounts of people with multidrug resistant virus and few treatment options left, the authors conclude that “judicious use of this strategy may serve as the necessary bridging mechanism that will allow selected patients to eventually benefit from more attractive therapeutic options as they emerge.”
Further information on this website
Lee N et al. Rates of Disease Progression among Human Immunodeficiency Virus–Infected Persons Initiating Multiple-Drug Rescue Therapy. Journal of Infectious Diseases;188:137-141, 2003