A study by St Mary's Hospital in London has found that six patients who discontinued therapy after approximately three months of treatment initiated during primary infection still had viral load controlled below 5,000 copies after more than 12 weeks off treatment. In one case an initial viral rebound to greater than 400,000 copies was spontaneously reduced to less than 1,000 copies within four weeks of treatment discontinuation. In a second case an individual off treatment for 48 weeks still has viral load below 5,000 copies.
Participants were recruited to the study by the Jefferiss Wing Clinic, which was able to identify 20 seroconverters with indeterminate antibody test results and doumented seroconversion illness (evidence of very recent HIV infection).
Patients started treatment an average of 28 days after symptoms were recorded, suggesting that they had been identified within 7-8 weeks of infection. At the time they began treatment, the mean viral load was 166,966 copies and the mean CD4 count was 448 cells/mm3.
The average age of seroconverters was 26, and this average was substantially skewed by one 78 year old seroconverter, suggesting that the majority of cases were picked up in gay men under the age of 25. Dr Sarah Fiddler of St Mary's Hospital told aidsmap that seroconverters were recruited to the study at a rate of two to three per month in one of London's busier GUM clinics.
Participants were not randomised, and five individuals opted not to undergo treatment. A further five individuals have yet to discontinue treatment and four have yet to complete 12 weeks off treatment. All participants received a combination of AZT, 3TC (in the form of Combivir) and nevirapine.
Participants experienced viral load falls below 50 copies after an average of 100 days on treatment (14 weeks), and continued treatment until they had a viral load below 50 copies.
Participants will be encouraged to start treatment again if their CD4 cell counts fall below 350 cells/mm3.
Dr Fiddler said that seroconverters are still sought to join the study, and that the study will extend to other UK centres within the next few months. A randomised study of treatment versus no treatment, called the Spartak study, is to be carried out in Russia later this by St Mary's Hospital in collaboration with the Moscow AIDS Centre.
Reference
Fiddler S et al. Short course HAART in primary infection. Seventh Annual Conference of the British HIV Association (BHIVA), abstract O4, 2001.