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close this bookUNAIDS-Sponsored Regional Workshops to Discuss Ethical Issues in Preventive HIV Vaccine Trials (UNAIDS, 2000, 52 p.)
close this folderWORKSHOP REPORTS
close this folderENTEBBE, UGANDA, 27-29 APRIL, 1998
View the document1. Phase I/II (Safety and Immunogenicity) Trials
View the document2. Phase III Trials
View the document3. Vulnerability to Harm and Exploitation
View the document4. Community
View the document5. Ethical Review
View the document6. Intellectual Property
View the document7. Control Arm in Trials
View the document8. Informed Consent
View the document9. Counselling
View the document10. Gender, Pregnancy and Breast-Feeding
View the document11. Children
View the document12. Discrimination
View the document13. Treatment and Care
View the document14. Endpoints in Vaccine Trials
View the document15. Compensation for Injury or Harm
View the document16. Access and Availability of Vaccine

1. Phase I/II (Safety and Immunogenicity) Trials


A given study should reflect the needs of the host country, and the decision to undertake the study should rest with the host country. In most cases, phase I/II trials should be conducted in a sponsor country prior to being conducted in a host country, especially if the infrastructure in the host country limits its ability to determine the safety and immunogenicity of a candidate vaccine. However, in a significant minority of cases, conditions in the host country may warrant the conduct of a first phase I/II trial, to be carried out with the requisite scientific rigor. In addition, phase I/II trials should generally, but not necessarily, be repeated in a host country prior to phase III trials in that country in order to examine safety and immunogenicity in the local context of human genetics, nutrition, coexisting diseases and prevalent viral subtypes. Repeating phase I/II trials will also have the benefit of building experience, knowledge, understanding and infrastructure among the public, the government and the scientific community prior to a phase III trial.


Scientific data for the candidate vaccine need to be examined by a scientific review body in the host country. It was acknowledged that there is not currently consensus within the scientific community about what level and type of immune response is likely to identify an effective vaccine.

Community representatives need to be involved in the evaluation of a candidate vaccine being considered for a trial in the host country. This might be accomplished through community representation on the scientific review committee.

A list of conditions under which a trial may be conducted in a host country should be developed, and must include adequate ability to conduct scientific and ethical review. International bodies such as UNAIDS should play a role in developing these guidelines and assisting countries to develop capacity.


Should a country like Uganda, which now has considerable infrastructure developed, be prohibited from conducting a phase I/II trial prior to the same trial being carried out in a sponsor country? The purpose would be primarily to ensure that problems with safety are dealt with before subjecting individuals in the host country to potential harm. Does a country like Uganda require this protection? Or, is there a point where the host country should be able to determine on its own whether it will accept the risks of conducting the first phase I/II trial? This was identified as an important issue for Uganda. Some felt that a country such as Uganda should consider taking the step of conducting a phase I/II trial even if the same trial has not previously been conducted in a sponsor country. One circumstance in which this might be appropriate is where the candidate vaccine targets a viral subtype not present in the sponsor country. In addition, this could speed up the process of vaccine development, as the phase I/II trial would only need to be conducted once, rather than being repeated in the host following trials in the sponsor country. It was pointed out that it might be important to make a distinction between a trial for a new vaccine ‘concept’ and a trial for a new ‘product’ for which the concept has already been tested (e.g. a change in subtype specificity for a gp120 candidate that has already had phase I/II trials in a sponsor country for a different subtype).