Kapulu 2024 summarizes the "Fourth Controlled Human Infection Model (CHIM) meeting—CHIMs in endemic countries," that was held from May 22 to 23, 2023, in Kenya and had a subsection on SARS-CoV-2. Proposed CHIM as a valuable avenue for studying disease and immunity, especially as phase 3 trials on new vaccine candidates become impractical in a highly immune population. Suggest long-term follow-up (minimum 180 days) to monitor long-term sequelae, including long-COVID.
Jamrozik 2024 reports on the "Ethical Approval for Controlled Human Infectious Model (CHIM) Clinical Trial Protocols" workshop, held from May 30 to 31, 2023, in Brussels, and organized by the European Vaccine Initiative (EVI) and the International Alliance for Biological Standardization (IABS). It brought together diverse global stakeholders to address ethical oversight and the integration of CHIM studies into pharmaceutical development. Recommendations for COVID-19 CHIM studies emphasized the need for rigorous informed consent processes, careful participant selection to minimize risks, and robust ethical oversight guided by frameworks like the WHO criteria. Additionally, they called for transparent public engagement, effective risk mitigation strategies, and long-term follow-up of participants to address concerns about safety and potential long-term effects.