People treated for HIV very soon after contracting the virus are more likely to be able to control the virus for an extended period after stopping antiretroviral (ARV) therapy, a phenomenon known as posttreatment control, aidsmap reports.
Publishing their findings in The Journal of Infectious Diseases, researchers from the CHAMP study analyzed pooled results from 10 randomized controlled trials and four cohort studies that largely involved ARV treatment interruption; all were conducted in the United States and Canada and published between 2000 and 2017.
The study defined posttreatment control of HIV as interrupting ARV treatment and then experiencing a viral load of 400 or below at two thirds or more of the points when viral load was measured during a period of at least 24 weeks. The investigators identified 67 people who fit this definition.
Of those in the pooled cohort who started HIV treatment soon after contracting HIV, 38 (13 percent) achieved posttreatment control, while of those who started ARVs during the chronic period of HIV infection, 25 (4 percent) achieved the same. Among those who achieved such control, the average time on ARVs before achieving posttreatment control was 28 months for those who began treatment soon after contracting the virus and 67 months for those who started during the chronic period of infection.
On average, posttreatment control lasted 21 months. Three quarters of the individuals maintained posttreatment control for longer than a year and 22 percent did so for five years or longer. Two individuals, each treated during early infection, have continued in a state of posttreatment control for longer than a decade.
On average, those experiencing posttreatment control experienced a decline of 32 CD4 cells per year while off ARVs, compared with a steep drop of 221 CD4 cells per year among those who interrupted treatment but did not achieve posttreatment control.
Forty percent of those who achieved posttreatment control had at least one viral load test result of greater than 400 after stopping their ARVs and 31 percent had at least one result of greater than 1,000. Such spikes occurred during the initial period after their treatment interruption, an average of eight weeks and a maximum of 24 weeks after stopping treatment. Afterward, these individuals proceeded to regain control of the virus without ARVs.
Data regarding the minority of posttreatment controllers who received very frequent viral load tests—weekly on average—indicated that two thirds of them had at least one viral load test result of greater than 400 after stopping ARVs, while 45 percent had at least one viral load of at least 1,000, 33 percent had at least one viral load over 10,000 and 11 percent had at least one viral load over 100,000.
To read the study abstract, click here.
To read the aidsmap article, click here.