Two new antiretroviral drugs have recently become available to a limited number of people with HIV needing alternatives to already licensed treatments, as they enter the drug approval process.

A Special Access Scheme has started for atazanavir, a new protease inhibitor manufactured by Bristol-Myers Squibb. Studies have shown atazanavir to be a potentially powerful anti-HIV treatment which promises to have a much more desirable cardiovascular risk profile than some other PIs.

Protease Inhibitors have been linked with raised blood lipids (cholesterol and triglycerides), raising questions about the long-term risk of developing heart disease for people on PI treatment. Atazanavir has not yet been studied long enough to determine if it is free of the same problems, but short-term studies have been promising. Whether or not the drug can cause body-shape changes is not yet understood.

In a separate development, Roche’s T-20 (enfuvirtide, Fuzeon) has also been made available, on an extremely limited basis, through a compassionate access program. T-20 comes from new group of drugs in development called entry inhibitors, which act to prevent HIV from entering CD4 cells. It is the first drug in this class to come so far in clinical research. T-20 is administered by an injection under the skin, so people will be taught to self-administer the treatment.

Two clinical trials of T-20 are still underway, with a number of Australian patients enrolled; however worldwide supplies of the drug are extremely limited. With just 19 Australian places initially available on the new compassionate access program, HIV prescribers across Australia have been asked to nominate patients in urgent need of access to T-20. The criteria for access include having a CD4 count below 100, and being unable to manage HIV with available drug combinations. More places are expected to open up on the program as the drug becomes available.