Establishment of a Mesoamerican-Caribbean south-south research platform: Challenges in the Meriva (curcuminoids) Gastric Cancer Chemoprevention Trial.

Gastric adenocarcinoma (GAC) is the fourth-leading global cause of cancer mortality and leading infection-associated cancer. High incidence regions include Latin America and Eastern Asia. Immigrants from high incidence regions maintain their GAC risk. GAC is a major U.S. cancer disparity, incidence rates are 2-10 time higher in non-white populations. Emerging guidelines recommend 3-year surveillance endoscopy for patients with high-risk gastric premalignant conditions (GPMCs). Clinical trials of GPMC chemoprevention agents are lacking. We conducted an NCI Division of Cancer Prevention-funded, phase II placebo-controlled chemoprevention trial in patients with GPMCs (atrophic gastritis, intestinal metaplasia) with a highly bioavailable preparation of curcuminoids (Meriva®). The trial sites in Puerto Rico and rural Honduras had important characteristics: (1) representative Caribbean and Mesoamerican populations, linked to large U.S. immigrant populations; (2) high prevalence of H. pylori infection and GPMCs; (3) absence of turmeric and curcuminoids in the local diets; (4) proven bidirectional collaboration with U.S. academic institutions. H. pylori-negative GPMC patients were randomized to study drug (500 mg po bid) or placebo for 180 days (NCT02782949), with primary outcomes based upon histologic parameters. Principal study challenges included: (1) international regulatory environment; (2) research infrastructure strengthening, particularly in Central America; (3) participant recruitment in Honduras wherein only 10-15% are H. pylori negative; (4) the Covid-19 pandemic; and (5) natural disasters (3 hurricanes). There were no losses to follow-up related to the pandemic or natural disasters. In conclusion, the south-south partnership provides a model for chemoprevention and translational studies in Latino populations with prevalent cancers such as GAC.