Risk and safety in clinical trials

The process of evaluating candidate vaccines can involve some risk.  All candidate vaccines used in human clinical trials have been extensively tested in laboratory experiments. When clinical trials take place on humans, continued safety testing remains an objective throughout all phases of clinical trials. 

There needs to be the fullest possible disclosure about the risks in any HIV vaccine trial.  The nature, magnitude and probability of all potential harms resulting from participation in an HIV preventive vaccine trial should be specified in the research protocol (See par 9. of the Guidelines on Ethics for Medical Research: HIV preventive vaccine research).   It is important that when any trial participant gives written consent to participate in an HIV vaccine trial that she or he must do so having an understanding of any possible positive or negative consequences on his or her health (This is a requirement of the National Health Act of which the relevant section is not yet in operation).  The Medicines Control Council and relevant ethics committee must also determine whether the risks inherent in the proposed research are at an acceptable level, whether they have been reduced to the minimum necessary to achieve the research objective, and are outweighed by the probable benefits (See e.g. par 9.9 of the above ethical guidelines).  Appropriate insurance must also be taken for research-related injury caused by certain circumstances like negligence on the side of the trial site, although this does not cover all harm.  In addition sponsors may establish an independent data-monitoring committee to access progress in the trial (See para 4.8 of the Guidelines for good practice in the conduct of clinical trials in human participants in South Africa).   This has become the standard for the larger scale HIV vaccine trials.  Such a committee may close down the trial.

Masikhulisane SAAVI Community Involvement Programme aims to educate affected communities about clinical research to enable communities and individuals to make informed decisions.  The South African Constitution makes it clear that no person may be subjected to medical experimentation/research without their informed consent.  This means that everyone must make a free and informed decision whether or not to participate in HIV vaccine trials.

Masikhulisane recommends to anyone considering whether to participate in a trial or not, that they should find out and understand as much as possible about the trial.  Some of the questions that should be asked (the answers to many of which should be found in the informed consent form) include the following (this is not a complete list):

• What is the purpose and different objectives of the study?
• Why do researchers believe the candidate vaccine being tested may be effective and has it been tested before?
• What are possible risks, side effects and benefits of the study?
• How long will the trial last?
• How will the trial affect my daily life?
• Will I be reimbursed for expenses?
• Will the results of the trial be provided to me?
• If new information relating to the trial comes to light, will I be informed?
• If I seroconvert during the trial as a result of continued high risk behaviour of what referral or level of care can I be assured?
• Will my community have access to the vaccine if the candidate vaccine is successful and is eventually licenced?

A vaccine is the best hope to control the HIV epidemic as has been demonstrated by the control of other global viral epidemics such as smallpox.  In order to eventually license a safe and effective vaccine clinical trials have to rely on trial participants who give their informed consent to participate in trials.  Progress in medicine and health research, and in this case in HIV vaccine research, therefore relies on a foundation of openness and honesty. 

Prepared by the Masikhulisane SAAVI Community Involvement Programme
February 2007