Starting HIV treatment before CD4 cells drop too low reduces the risk of AIDS and HIV-related illnesses, according to the same large study, called HPTN 052, that proved early treatment cuts transmission risk by 96 percent. In the trial, 1,763 HIV-positive participants with CD4s between 350 and 550 were randomly selected to either start antiretrovirals immediately or to wait until their CD4s had either dropped to 250 or until the participants developed a symptomatic disease related to HIV. The study found that the early starters enjoyed a 36 percent reduced risk of an AIDS-defining illness and a 27 percent lowered risk of one or more of the following “primary outcomes”: death, an AIDS diagnosis, tuberculosis (TB), a severe bacterial infections, cardiovascular disease, serious liver disease, end-stage kidney disease, non-AIDS cancers or diabetes. However, the primary outcome benefit was not statistically significant, meaning it could have occurred by chance.