EuroVacc preparing for clinical trials of subtype C AIDS vaccine

This article is more than 22 years old.

A major European collaboration to design and test an AIDS vaccine is hoping to launch its first clinical trials this summer at Lausanne University Hospital, Switzerland, and at St Mary's Hospital, London, UK. However, a report issued by Reuters Health is misleading in suggesting these plans are more advanced, and larger in scale, than is in fact the case.

The vaccine is manufactured by Aventis Pasteur under a public-private partnership agreement which has been funded for some years by the European Commission. It is a "cluster project" which includes more than 30 different research groups across Europe.

The vaccine consists of a DNA primer followed by a NYVAC (modified vaccinia) booster. Both vaccines contain DNA sequences based on HIV genes gag, pol, nef and env from an HIV subtype C virus. Potentially, this combination can stimulate both antibodies and cellular immune responses against HIV. However, the value of these immune responses in protecting people against HIV remains to be proven. Vaccines of this kind have been shown to protect monkeys from HIV-related viruses, by suppressing the level of the virus in the body rather than by preventing infection outright.

Glossary

deoxyribonucleic acid (DNA)

The material in the nucleus of a cell where genetic information is stored.

subtype

In HIV, different strains which can be grouped according to their genes. HIV-1 is classified into three ‘groups,’ M, N, and O. Most HIV-1 is in group M which is further divided into subtypes, A, B, C and D etc. Subtype B is most common in Europe and North America, whilst A, C and D are most important worldwide.

clinical trial

A research study involving participants, usually to find out how well a new drug or treatment works in people and how safe it is.

boosting agent

Booster drugs are used to ‘boost’ the effects of protease inhibitors and some other antiretrovirals. Adding a small dose of a booster drug to an antiretroviral makes the liver break down the primary drug more slowly, which means that it stays in the body for longer times or at higher levels. Without the boosting agent, the prescribed dose of the primary drug would be ineffective.

env

One of the three proteins encoded within the retroviral genome.

The form of vaccinia (smallpox vaccine) used has been chosen for safety when given to individuals who are immunosuppressed, although initial trials would be in low-risk, healthy, HIV negative volunteers. It is impossible for the vaccine to give rise to HIV infection.

The planned EuroVacc clinical trial programme will begin by testing each component of the vaccine separately before testing them in combination. The trials await approval from regulatory authorities and aidsmap has been told the first stage is unlikely to start before July 2003.

If these early trials show promising immune responses in trial volunteers, it is hoped that future clinical trials will include populations at high risk of HIV in Europe as well as in Africa and Asia.

As of April 2003, low-risk HIV-negative volunteers are still being sought to take part in vaccine trials in London of the DNA-MVA combination sponsored by IAVI (follow links below for further information, including contact details).

Further information on this website

HIV DNA vaccine: volunteers sought for London study (St Thomas's hospital)

First London volunteer vaccinated in ground-breaking trial (St Mary's hospital)