FIT Biotech’s proprietary Gene Transport Unit (GTU®) vector delivery platform has enabled the company to develop an advanced HIV vaccine candidate that is currently in Phase II therapeutic clinical trials in South Africa.
South Africa is one of the countries most seriously affected by HIV. Recent statistics indicate that at least 5.5 million people, or around 20% of the population, are currently infected. Women are particularly affected, with almost one in three attending public antenatal clinics infected.
The scale of the problem both here and worldwide – AIDS now kills more people around the world than any other infectious disease – means that a vaccine is the best way forward.
Most HIV vaccine efforts to date have been aimed at developing a preventive HIV vaccine that will protect non-infected individuals if exposed at a future point. Therapeutic vaccination of individuals already infected, in contrast – employing an HIV vaccine that can modify the course of the infection and its progression towards the disease by maintaining a low viral load and high or constant CD4 cell counts – offers the most hope for chronically infected individuals not eligible for antiretroviral therapy.
This is especially important in South Africa, since access to antiretroviral therapy through the public sector is limited to individuals with a CD4 cell count of < 200 cells/mm3, which is relatively late in the progression of the disease to full-blown AIDS.
Multiple gene sequences
The development of an HIV vaccine is complicated by the ability of the virus to mutate rapidly, resulting in up to a 20% variation between different HIV subtypes (Clades A-K). FIT Biotech has addressed this challenge by designing an antigenic artificial protein, known as MultiHIV, composed of sequences from six HIV genes and incorporating antigens from the A, B, C, and FGH HIV clades.
This MultiHIV antigen has been estimated to cover more than 95% of the theoretical antigenic variability within HIV strains – and lies at the heart of FIT Biotech’s lead HIV vaccine candidate, which is a DNA plasmid inserted within the company’s proprietary GTU® vector technology.
The University of Witwatersrand’s Perinatal HIV Research Unit is currently evaluating the vaccine in a Phase II therapeutic clinical trial in Soweto. The trial commenced in 2006 with 60 treatment-naïve HIV-infected individuals, and is expected to be completed in early 2009.
|The FIT Biotech HIV vaccine candidate is currently being trialled at the Chris Hani Baragwanath Hospital in Soweto in South Africa, one of the countries suffering the most from HIV infection and AIDS.