The lives of nearly 37 million people around the world will change the day science finds a cure for HIV. Today is not that day.

But we are closer than ever, thanks to a team of British scientists carrying out trials of a highly experimental treatment. The researchers, who hail from five different universities in the UK, announced on Sunday that one of their patients, a 44-year-old British man infected with the virus, showed zero signs of the deadly virus in his body after completing their treatment. They’re reluctant to call it a “cure” — a single successful trial, after all, doesn’t prove much — but they are optimistic that their treatment, based on the promising “kick-and-kill” strategy of targeting the virus, represents a huge step toward finding one.

The “kicking” and “killing” in this approach to battling the virus refers to the two-step process of waking up dormant, virus-laden cells and then striking them down when they become active. Antiretroviral therapy drugs such as AZT and 3TC, which have been used for decades, are useful for slowing down the rate at which HIV reproduces in the body, but it doesn’t eliminate the virus altogether. Often, the virus stays dormant in the DNA of specialized cells known as memory T-cells, sometimes for years, or even decades; because they’re not actively producing the virus, there aren’t any markers on the cell surface flagging down the immune system to destroy it.

What the “kick and kill” strategy does is shake up those sleeping memory T-cells with a combination of drugs. As HIV starts, once again, to rear its ugly head on the surface of the infected cells, treatment moves into the “kill” phase: Patients are injected with a drug normally used for cancer called vorinostat, which helps their immune systems recognize HIV-carrying cells and kill them.

The process is not a new one, but the recent breakthrough by the British team represents the first time the virus appears to have been completely cleared from the body using this technique. So far, it isn’t clear what tweaks the researchers have made to existing kick-and-kill strategies, but their unprecedented success suggests that they’re onto something new. As they measure the effects of the treatment on the 49 other participants involved in the study, more details on the HIV-blasting treatment will inevitably be made public.

But will it ever constitute a cure? That’s a controversial topic, one that rests not only on the success of such trials but also on how we choose to define what a “cure” would even mean. Right now, scientists can only say with confidence that the seemingly cured individual no longer has traces of HIV in his bloodstream — in itself miraculous — but it isn’t clear yet whether the stubborn virus is still lurking elsewhere in his cells. Only time will tell how significant this breakthrough is, though by the looks of it, it could be a game-changer.