A new category of drugs has shown promising results for HIV/AIDS patients who failed to respond to other treatments, a new study shows.

Especially when combined with other medications, raltegravir - the first in a new class of anti-retroviral drugs called integrase inhibitors - dramatically reduced the presence of the HIV virus and boosted immunity in clinical-trial patients, according to the study in the British journal, The Lancet.

Integrase inhibitors act by targeting and disrupting an enzyme that facilitates the insertion of the HIV virus into the host's cellular genome.