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 of GAC include Latin America and Eastern Asia. Immigrants from high-incidence regions maintain their GAC risk. GAC is a major U.S. cancer disparity, and its incidence rates are 2 to 10 times higher in non-White populations. Emerging guidelines recommend 3-year surveillance endoscopy for patients with high-risk gastric premalignant conditions (GPMC). Clinical trials of GPMC chemoprevention agents are lacking. We conducted a NCI Division of Cancer Prevention-funded, phase II placebo-controlled chemoprevention trial in patients with GPMCs (atrophic gastritis and intestinal metaplasia) with a highly bioavailable preparation of curcuminoids (Meriva). The trial sites in Puerto Rico and rural Honduras had important characteristics: (i) representative Caribbean and Mesoamerican populations, linked to large U.S. immigrant populations; (ii) high prevalence of Helicobacter pylori infection and GPMCs; (iii) the absence of turmeric and curcuminoids in local diets; and (iv) proven bidirectional collaboration with U.S. academic institutions. H. pylori-negative patients with GPMCs were randomized to the study drug (500 mg po bid) or placebo for 180 days (NCT02782949), with primary outcomes based upon histologic parameters. Principal study challenges included (i) an international regulatory environment; (ii) research infrastructure strengthening, particularly in Central America; (iii) participant recruitment in Honduras, wherein only 10% to 15% are H. pylori negative; (iv) the COVID-19 pandemic; and (v) natural disasters (three 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.