AIDS/HIV experts gathered in Sydney for day 3 of the 4th International Aids Society (IAS) Conference discussed the progress being made in research and treatment development for fighting the global pandemic. The main thrust of a new generation of HIV treatments appears to be stopping the virus from spreading among people, and from replicating itself inside a person, as well as attacking it directly, which was the main thrust of earlier treatments.
The day’s plenary discussions focussed on three main areas: Male Circumcision, Gene Therapy and New Treatments.
In a session titled “Male Circumcision: From Research to Practice”, Robert Bailey, of Professor of Epidemiology at the University of Illinois at Chicago and Research Associate at the Field Museum in Chicago, US, said that scientists now have “compelling evidence” that male circumcision reduces HIV transmission from women to men by around 60 per cent. Over 45 observational studies, three major clinical trials and several biological studies support this.
Bailey himself has conducted studies in Uganda, Kenya, Malawi and Zambia, and also in the US.
He described estimating models that show circumcision could help prevent millions of new HIV infections in sub-Saharan Africa. About 30 per cent of the world’s males are circumcised, and in Africa this figure is 67 per cent. Circumcising more men in the high HIV prevalence areas would be very cost-effective and would have enormous impact, says Bailey.
In another session, Dr John Rossi who is Professor of Molecular Biology and Dean of the Graduate School of Biological Sciences at City of Hope’s Beckman Research Institute in the US led a discussion titled “Use of Gene Therapy to Develop HIV Treatments”.
Gene therapy is a cutting edge biotechnology that helps to fight disease by switching off the “bad” genes that promote it.
Rossi and colleagues working at his lab have found three small pieces of RNA, ribonucleic acid, that behave like gene inhibitors that stop HIV from replicating itself. They are developing a “virus vector” that will insert the DNA of the RNA inhibitors into patients. The RNA inhibitors target the virus directly, and an associated viral protein, and also block a site on cells that interact with HIV. The “triple construct vector” is now being tested in two different human trials by Rossi and his team.
A third plenary session dealt with the topic of “New Agents and Treatment Strategies”. This was led by Dr Joseph Eron, who is Professor of Medicine in the Division of Infectious Diseases at the University of North Carolina at Chapel Hill School of Medicine in the US.
Eron said there is a lot of change in the field of HIV clinical care. Existing treatments are getting better and new classes of HIV drugs are appearing that work in completely new ways.
He said that more than 20 antiretroviral treatments were now working in the field, but he was most excited by a new type of drug called integrase inhibitors. Integrase inhibitors stop HIV getting into new cells. There are two drugs in development, one is already being trialled in Australia, Raltegravir. This drug is supposed to be more potent than existing drugs and showed fewer adverse events, said Eron. He also said such compounds now gave patients with resistant HIV strains real hope that their viral load could be suppressed to “undetectable levels”.
Delegates were upbeat about the new drugs and genetic therapies, and a new word entered the discussion – “eradication”. This is perhaps the first time that an HIV/AIDS conference has dared to use this word, eradication, in what appears to be more than a wishful sense.
Written by: Catharine Paddock