Potential new treatment for HIV

Australian biomedical research company Biotron Limited has announced preliminary results from a human trial of its lead antiviral drug BIT225 to treat HIV infection ‘hidden’ in reservoir precursor cells.

The trial has demonstrated that BIT225 targets HIV replication in some types of cells in treated patients. The monocyte cells become infected with HIV and are the seeds of hidden HIV pools in patients, setting up long-lived reservoir cell populations in various sites in the body.

The trial showed that BIT225 is capable of significantly reducing virus levels in these cells.

Biotron managing director Dr Michelle Miller said the data was “very encouraging” and could pave the way for a new generation of HIV treatment.

“We are thrilled with these results, which validate Biotron’s novel approach to tackling HIV,” Miller said.

“For the first time we have a potential treatment which may halt the ongoing cycle of infection and reinfection with virus from these long-lived cells.

“This is a significant development for our company and has the potential to impact HIV research globally, particularly in terms of treatment in an important HIV reservoir.

“The results suggest that BIT225 is a candidate agent that could be useful in future eradication strategies.”

Targeting virus reservoirs is regarded as the ‘holy grail’ of current HIV research.

Monocytes are blood cells that become infected with HIV, then move out of blood vessels into different organs such as the liver, lungs, gut and brain, where they mature into macrophages.

HIV replicates at low levels in these infected macrophages, acting as ongoing sources of virus in patients. Existing drugs are ineffective in treating HIV in these cells.

Current approved anti-HIV drugs target HIV in T cells, and their use is aimed at keeping virus levels in the blood in check and ensuring T cell counts stay in a healthy range. However, these approved treatments do not target underlying viral reservoirs that exist in other cells in the body and which act as ongoing sources of HIV infection.

The BIT225 trial was conducted on 21 patients at an international clinical trial unit in Bangkok, Thailand. Patients enrolled in the study were HIV-positive, with high levels of virus and good CD4+ T cell counts.

None had previously received treatment with anti-retroviral drugs.

“This result validates our earlier preclinical, cell culture-based data and the company’s ongoing HIV program,” Miller added

Further analyses are ongoing, and completed safety data from the trial has yet to be reviewed. Full results from the trial are expected to be presented at a scientific conference later in 2013.

BIT225 is also in development for treatment of Hepatitis C virus (HCV) and has show great promise in that arena also.