Norwood, Dalton A.

Abstract Globally, gastric adenocarcinoma is the fourth leading cause of cancer mortality and a major cancer disparity in the United States. Chemoprevention strategies are lacking for high-risk individuals with gastric premalignant conditions (GPMC). Curcumin, the principal curcuminoid in turmeric, exerts immunomodulatory effects in the epithelium and against Helicobacter pylori, and studies suggest chemoprevention potential. We conducted a double-blind, phase IIa randomized controlled trial in high-risk populations in Puerto Rico and Honduras. We investigated the utility of a bioavailable formulation of curcumin (Meriva) among individuals with H. pylori–negative GPMC, specifically, multifocal atrophic gastritis (MAG) or gastric intestinal metaplasia (GIM). Patients were 1:1 randomized to 1,000 mg Meriva daily or placebo for a 6-month intervention with endoscopy at baseline and 6 months. Outcomes included assessment of epithelial cytokine and chemokine levels, histology, and DNA damage as assessed by γ-H2AX phosphorylation IHC. Of the 110 subjects screened, 50 participants were randomized, and 48 completed the trial. A significant reduction in gastric mucosal IL1β levels from baseline in the gastric body, the primary endpoint, was observed in the Meriva group (P = 0.032). Changes in epithelial IL8, TNFα, and inducible protein 10 levels and gastric mucosal histology and DNA damage (secondary endpoints) were similar between arms. Curcumin (Meriva) was safe, well-tolerated, and showed potential as a curcuminoid chemoprevention agent in H. pylori–negative patients with GPMC. A potential reduction in gastric inflammation as measured by gastric mucosal IL1β levels was observed. Further studies are warranted, including studies in H. pylori–positive individuals, based upon the curcuminoid direct effects on H. pylori. Prevention Relevance: Gastric adenocarcinoma is a leading cause of cancer mortality worldwide. Chemoprevention candidates for GPMCs are limited. This randomized phase IIa trial evaluated a bioavailable curcumin formulation in high-risk individuals with MAG and GIM. The results support further study of curcuminoids for gastric cancer risk reduction. See related Spotlight, p. 387 See related article by Morgan et al., p. 391

Abstract 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.