Recent work on informed consent to preventive AIDS vaccine trials

Harrison K et al. Medical eligibility, comprehension of the consent process, and retention of injection drug users recruited for an HIV vaccine trial. Journal of the Acquired Immune Deficiency Syndromes and Human Retrovirology 1995;10:386-90

A 17 item true/false test was used to test comprehension of issues related to the informed consent process. Data are given for a total of 175 potential participants from the United States. They were asked questions such as: "Person who join in this HIV vaccine study will no longer need to use condoms when they have sex with new partners"; "People who join this study will never again have to worry about catching HIV infection no matter what they do"; "People who join this study will need to worry less than people in the study about catching HIV if they forget to use a condom with a new sex partner". The study showed that most potential participants answered these and other questions correctly.

Celentano DD et al. Willingness to participate in AIDS vaccine trials among high risk populations in northern Thailand. AIDS 1995;9:1079-1083

A total of 2180 subjects from different groups (female commercial sex workers, men attending sexually transmitted disease clinics, conscripts in the Royal Thai Army, men discharged from the army) were interviewed. They were asked questions about awareness of vaccines and AIDS vaccine development efforts, whether they would definitely join a trial if asked (25% would), and whether they would definitely accept a vaccine if they were convinced it was safe and effective (between 38% and 52% would). It is important to note that only between 0.9% and 10.9% said that they would definetely refuse to join an AIDS vaccine trial. Barriers to participation include among others concerns with discrination and vaccine side-effects.

Jackson DJ et al. Acceptability of HIV vaccine trials in high-risk heterosexual cohorts in Mombasa, Kenya. AIDS 1995;9:1279-1283

A questionnaire was administered to 407 subjects. 91% of the women and 67% of the men said they would definitely agree to particiapte in vaccine trials, after the experimental nature of the vaccine, the double blind design, the prolonged follow-up and the potential change in serostatus were explained to them. 16% of the men and none of the women would not participate in a trial. 9% of the men and 6% of the women anticipated decreased condom use, and 9% of the men and 3% of the women anticipated increased number of sex partners if they participated in the trial.

Jenkins RA et el. Incentives and disincentives to participate in prophylactic HIV vaccine research. Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology 1995;9:36-42

255 people emplyed in health care service and research settings in Thailand completed an anonymous questionnaire. 40% would defintely not particpate, 20% were strongly negative, 32% would perhaps participate and 6% were strongly positive. Factors associated with willingness to participate were also investigated in this study (such as perceived personal benefits of joining, and social discrimination that might result).

Meyers K et al. HIV vaccine trials: Will intravenous drug users enroll? American Journal of Public Health 1994;84:761-766

257 intravenous drug users in the US completed a self- administered questionnaire about interest in vaccine trials. 52% expressed an interest in participating. 22% reported they would increase needle-sharing if they were sure that they could not get AIDS. 30% were unsure what a vaccine was, and 41% did not know that a vaccine could prevent disease acquisition. 39% would be willing to try a vaccine for HIV even if there was a slim chance of getting sick from it.

Meyers K et al. Will preventive HIV vaccine efficay trials be possible with female injection drug users? Journal of Acquired Immune Deficiency Syndrome and Human Retrovirology 1995;10:577-85

60% of 121 women reported that they would be willing to particpate in a vaccine trial. Of these baseline seronegative women, 28% shared needles, and 52% engaged in unprotected intercourse. The authors argue that "Given that seroconversions occur and that these women engage in high risk behaviors, report willingness to try an HIV vaccine, and can be retained for longitudinal assessment, they appear to be sutiable participants for preventive HIV vaccine efficacy trials".