|UNAIDS-Sponsored Regional Workshops to Discuss Ethical Issues in Preventive HIV Vaccine Trials (UNAIDS, 2000, 52 p.)|
|OURO PRETO, BRAZIL, 1-3 APRIL, 1998|
Preventive risk behaviour counselling, general HIV care and treatment, post-exposure prophylaxis and antiretroviral therapy (whether early or late) were all considered to be subject to the same ethical imperative; that is, all should be provided to trial participants according to the best scientific evidence for effectiveness available at the time of the trial. There was a strong sense of consensus on this issue.
This was perceived by the group as the most important topic to be discussed during the workshop, and the most likely to affect the progress of HIV vaccine trials.
It would not be ethical to deny counselling, post-exposure prophylaxis or antiretroviral or other treatment to participants solely for the purpose of making a vaccine trial more valid or statistically powerful.
Local capacity for counselling must exist or be developed, be flexible and multi-cultural, involve information and methodology at an appropriate level, and include distribution of condoms and needles. (However, it was also pointed out that in some countries, needle exchange is illegal.)
Post-exposure prophylaxis should be provided if it has come into common use in the host country. It was acknowledged that evidence that supports the effectiveness of post-exposure prophylaxis outside of the occupational setting is currently very limited.
Treatment for those who become infected should be provided at the level of that offered in the sponsoring country. It should continue at least for the duration of the trial, and further provision should be negotiated. This would include early antiretroviral treatment in the case where it is proven to be effective.
There should be a disease management or research protocol that all who seroconvert during the trial would enter.
It was acknowledged that making antiretroviral medication available in a study setting would be very expensive, but also that little research or effort has been dedicated thus far to developing creative economic mechanisms for providing this.
The need to measure secondary endpoints was not perceived as a valid rationale for withholding early treatment if treatment was proven to be effective. In addition, it was not generally held that providing early treatment would necessarily preclude an analysis of vaccine effectiveness. There was discussion about the likely proportion of participants that would realistically be diagnosed during early infection, and would choose to accept early therapy. It was suggested that those who do not receive early treatment due to choice or circumstance may still contribute substantial data on which to base an analysis of effectiveness.
A test that is capable of distinguishing HIV infection from vaccine-induced antibody response would need to be made available to all participants by the sponsor.
Significant conflict arose in defining the appropriate measure by which to determine what level of treatment or prevention should be provided in a developing country research setting. There was agreement that scientific evidence for effectiveness of treatment or prevention interventions gives the most important guidance for what should be provided. There was also agreement that there should not be a compromise made solely because of limited resources in the host country. However, it was acknowledged that, in many cases, common treatment practice in developed or developing countries is not based on scientific evidence, but on prevailing opinion, or political or cultural persuasion. Terms such as best proven, best possible, standard of care, highest attainable and policy were considered, but each was found to have its own limitation. For example, there was a sense of mistrust when using the term highest attainable, since attainable is not an absolute, but is a function of priorities and decisions related to resource allocation. Who makes these decisions, and how they are made, have a great impact on the final outcome. This issue of defining the most appropriate measure was left unresolved.
Is this principle of providing what is best proven to those participating in the trial open to any qualification? To this a minority reluctantly answered that there may be exceptions to providing the best proven care, but that this was something that could only be determined in the local context, through the deliberation of an empowered and informed community.