On-Again, Off-Again HIV Treatment May Work
"There are two interpretations," Montaner says. One is that the patient was able to develop an immune response against HIV with the treatment interruptions. "That is very exciting," he says. But the other possibility may be that this patient just happened to be one of the rare people who naturally control HIV, and all this was just a smoke screen for what would have happened anyway.
Franco Lori, MD, at the Institute for Genetic and Human Therapy in Pavia, Italy, is one of the researchers who originally reported the Berlin patient. He agrees that the immune response can control the viral load and is actively seeking a way to elicit HIV-specific immunity as an "extra drug" to fight the virus.
"If you don't treat HIV, it takes over the immune system," Lori tells WebMD. "If you treat it with multiple HIV drugs, you get no immune-system involvement. In between, we think there is a chance of restoring the immune system."
Montaner is optimistic that his team has found a way to do this. Their new clinical trial is enrolling patients whose HIV is controlled by their HIV drug regimen. This regimen cannot include drugs that can't be stopped and started due to risk of resistance (such as Sustiva) or risk of dangerous side effects (such as Ziagen). Each patient then undergoes four progressively longer rounds of treatment interruption (two, four, and six weeks, followed by an open period). Before each new interruption, viral load must be brought back down to undetectable levels by the drugs.
Although not part of the trial, Montaner is monitoring a patient who -- in consultation with his physician -- is undergoing the treatment-interruption schedule being tested in the new clinical trial. With each treatment interruption, the rebound in the amount of virus in the patient's body was smaller than that seen previously. The virus rebounded at first -- and then steadily fell even thought the patient stayed off his HIV drugs. "His immune responses are going through the roof," Montaner says.
Montaner warns that there is no proof that this strategy works, and those patients who try it run considerable potential risk. If patients feel that they must interrupt their treatment, Montaner advises that they do so only under the close supervision of a physician. "We cannot tell a person not to do this," Montaner says. "If you choose to do it, it is your own decision. We are not telling people how to manage their disease. But if people are doing something already, we can follow them."