Community interpretation of a consent form and willingness to participate in a Nipah virus vaccine trial in Bangladesh

Introduction Clinical trials conducted in low resource settings of vaccines against unlikely pandemics generate practical barriers to achieving genuine informed consent. Uncertainty over the likelihood of the occurrence of emerging disease threats complicates risk-benefit considerations. We explored how people interpreted the language of a draft consent form for a Phase II trial of a vaccine against Nipah virus (NiV), a lethal bat-borne zoonosis, and assessed their willingness to participate after learning about the trial procedures. Methods We conducted a mixed-methods study collecting data from residents of Dhaka city, and Faridpur District between December 2021 and November 2022. Our qualitative team revised a draft consent form with input from the community, while the quantitative team conducted face-to-face interviews of 978 household heads making vaccine and treatment decisions. Results We presented the consent form to 20 respondents. They expressed a desire to learn more about NiV disease and sought clarification on the vaccine trial process, use of a placebo, privacy and confidentiality, potential side effects, and compensation procedures. During the quantitative survey, among 328 respondents who indicated a willingness to participate in the vaccine trial, only 1 % (3/328) were familiar with the concept of a placebo. After the quantitative data collection team explained the meaning of a placebo, 61 % (199/328) expressed their willingness to participate in the trial. Conclusion Our data suggest that obtaining informed consent for vaccine trials against pathogen with pandemic potentials is feasible but requires a commitment to eliciting study participants' perspectives and tailoring study materials to address their concerns and gaps in understanding.