What motivates or demotivates injecting drug users to participate in hypothetical HIV vaccine efficacy trials? A qualitative study from urban Tanzania

Acceptability of a Future HIV Vaccine: A Rapid Scoping Review

BACKGROUND

A HIV vaccine is not available yet, but perceptions of HIV vaccines will be important to explore before their roll-out for effective vaccine promotion. This article presents the findings of a rapid scoping review of the literature to identify individual, social, and vaccine-related factors associated with the acceptability of a future HIV vaccine.

METHODS

We searched 5 databases (Medline OVID, Embase, PsycINFO, Web of Science, and Cochrane) using relevant keywords and Medical Subject Headings. All articles, regardless of study design, publication year, and geographic location, were included if they examined HIV vaccine acceptability and its underlying factors.

RESULTS

We retrieved 2386 unique articles, of which 76 were included in the final review. Perceived benefits (34.2%) and perceived susceptibility (25.0%) were primary individual factors of HIV vaccine acceptability. Misinformation (17.1%) and distrust (22.4%) regarding future HIV vaccines, HIV stigma (30.3%), and social support (10.5%) were social factors of HIV vaccine acceptability. Vaccine efficacy (42.1%), cost (28.9%), and side effects (67.1%) were common vaccine characteristics influencing HIV vaccine acceptability. Altruism (10.5%) and risk compensation (26.3%) were also key factors.

CONCLUSIONS

Our analyses revealed that skeptical beliefs, negative perceptions, and misconceptions about HIV vaccines are real barriers to their acceptability. To alleviate HIV vaccine hesitancy and address trust concerns, strategic vaccine communication should be disseminated by trustworthy sources. Messages should impart accurate vaccine information and emphasize both individual and social benefits of HIV vaccination, as well as leverage social support in increasing willingness to get a future HIV vaccine.

Comprehension of informed consent and voluntary participation in registration cohorts for phase IIb HIV vaccine trial in Dar Es Salaam, Tanzania: a qualitative descriptive study

BACKGROUND

Informed consent as stipulated in regulatory human research guidelines requires volunteers to be well-informed about what will happen to them in a trial. However, researchers may be faced with the challenge of how to ensure that a volunteer agreeing to take part in a clinical trial is truly informed. This study aimed to find out volunteers' comprehension of informed consent and voluntary participation in Human Immunodeficiency Virus (HIV) clinical trials during the registration cohort.

METHODS

We conducted a qualitative study among volunteers who were enrolled in the registration cohort of HIV clinical trials in Dar es Salaam, Tanzania. A purposive sampling strategy was used to obtain twenty study participants. The data were collected between June and September 2020 using a semi-structured interview guide. In-depth interviews were used to collect the data to obtain deep insights of the individual study participants on the comprehension of informed consent and participation in the clinical trial. A thematic analysis approach was used to analyze the data. Themes and subthemes were supported by the quotes from the participants.

RESULTS

Volunteers described comprehension of informed consent from different perspectives. They reported that various components of the informed consent such as study procedure, confidentiality, risk and benefits were grasped during engagement meetings. Furthermore, the volunteers' decision to participate in the registration cohort was voluntary. However, trial aspects such as health insurance, free condoms, and medical checkups could have indirectly influenced their reluctance to withdraw from the study.

CONCLUSION

Engagement meetings may increase the comprehension of informed consent among potential participants for HIV clinical trials. However, trial incentives may influence participation, and thus future research should focus on the challenges of giving incentives in the study. This will ensure comprehension and voluntary participation in the context of HIV clinical trials.