Establishing a filarial clinical research platform in a resource-limited setting: Lessons and experiences from Tanzania

This paper examines the establishment and lessons learned from the LeDoxy Trial, a multinational, double-blind, randomized, placebo-controlled study that evaluated doxycycline (200 mg/d and 100 mg/d) over six weeks for the treatment of filarial lymphedema in Tanzania's Lindi and Pwani regions. Conducted from 2018 to 2021 across four sites, the trial enrolled 420 participants aged 14-65 years, addressing a critical gap in lymphatic filariasis (LF) research in geographically remote and historically under-researched areas. The trial faced significant challenges, including limited pre-existing research infrastructure, community research fatigue, and disruptions from the COVID-19 pandemic, which delayed regulatory approvals and supply chains. To overcome these, the TAKeOFF Consortium with Tanzania's National Institute for Medical Research (NIMR) as local sponsor led a 12-month site preparation effort, upgrading Lindi's laboratory from a 2-star to a 4-star rating through infrastructure enhancements (e.g., centrifuges, freezers) and staff training in Good Clinical Laboratory Practice (GCLP). Community health workers (CHWs) leveraging established community-directed approaches from NTD control programs played a pivotal role, achieving a 92% retention rate through targeted recruitment, door-to-door engagement, and follow-up support, including the distribution of hygiene kits. The trial trained 93 healthcare professionals in LF management and clinical research, fostering a research culture despite initial resistance. Additional strategies included remote monitoring to adapt to travel restrictions and stakeholder collaboration to address cultural misconceptions, such as stigma around LF. These efforts not only ensured trial success but also created foundational capacity that has begun to support post-trial research activities, with ongoing evaluation needed to assess long-term sustainability. This paper provides comprehensive, integrated documentation of the infrastructure development process from laboratory accreditation and regulatory navigation to community engagement and sustainability planning, offering actionable guidance for conducting high-quality NTD trials in resource-limited settings. The lessons emphasizing local sponsorship, adaptive protocols, and community trust demonstrate how strategic investments in research infrastructure, local capacity-building, and stakeholder engagement can strengthen clinical research ecosystems in LMICs, advancing health systems, local ownership, and global health equity. This paper focuses exclusively on the operational and implementation aspects of establishing the trial infrastructure.