New York: A new combination therapy for a rare, deadly leukemia can send the disease into remission even in patients whose standard therapy has failed, researchers have found in a pilot study.

The new approach to battling T-cell prolymphocytic leukemia combines immunotherapy -- boosting the body's immune system -- with epigenetics, the manipulation of gene activity.

‘It was unbelievable, really, seeing a patient who had already failed Campath (the drug typically used to treat the disease) literally going back into remission,’ said one of the leaders of the study Thomas Loughran Jr., director of the University of Virginia Cancer Center in the US.

The experimental approach did not cure the patients, but it did send them all into remission, thus buying them more time to have the bone marrow/stem cell transplant that could save their lives.

The study looked at eight patients with T-cell prolymphocytic leukemia, an aggressive cancer that is extremely difficult to treat. It is also extremely rare, appearing most commonly in older men.

The experimental treatment made a significant difference for all the study participants.

‘There has been a revolution in the last few years seeing success with immunotherapy, and people speculated that perhaps if you combined epigenetic and immunotherapy, that might be even more spectacular,’ Loughran said.

‘This is proof of principle that this might be true,’ Loughran said.

Researchers believe that it is a cutting-edge combination that holds great promise not just for treating T-cell prolymphocytic leukemia but, possibly, many other cancers as well.

The drugs used in the treatment are already commercially available, meaning doctors could, in theory, administer the treatment without further testing.

Loughran, however, believes there needs to be an additional study, hopefully in a larger trial, but the rarity of the disease makes recruiting participants difficult.

The study was published online in the journal Science Translational Medicine.