Association of Sulindac and Erlotinib vs Placebo With Colorectal Neoplasia in Familial Adenomatous Polyposis: Secondary Analysis of a Randomized Clinical Trial

Abstract

Importance: Patients with familial adenomatous polyposis (FAP) are at markedly increased risk for colorectal polyps and cancer. A combination of sulindac and erlotinib led to a 71% reduction in duodenal polyp burden in a phase 2 trial.

Objective: To evaluate effect of sulindac and erlotinib on colorectal adenoma regression in patients with FAP.

Design, setting, and participants: Prespecified secondary analysis for colorectal adenoma regression was carried out using data from a double-blind, randomized, placebo-controlled trial, enrolling 92 patients with FAP, conducted from July 2010 to June 2014 in Salt Lake City, Utah.

Interventions: Patients were randomized to sulindac, 150 mg twice daily, and erlotinib, 75 mg daily (n = 46), vs placebo (n = 46) for 6 months.

Main outcomes and measurements: The total number of polyps in the intact colorectum, ileal pouch anal anastomosis, or ileo-rectum were recorded at baseline and 6 months. The primary outcomes were change in total colorectal polyp count and percentage change in colorectal polyps, following 6 months of treatment.

Results: Eighty-two randomized patients (mean [SD] age, 40 [13] years; 49 [60%] women) had colorectal polyp count data available for this secondary analysis: 22 with intact colon, 44 with ileal pouch anal anastomosis and 16 with ileo-rectal anastomosis; 41 patients received sulindac/erlotinib and 41 placebo. The total colorectal polyp count was significantly different between the placebo and sulindac-erlotinib group at 6 months in patients with net percentage change of 69.4% in those with an intact colorectum compared with placebo (95% CI, 28.8%-109.2%; P = .009).

Conclusion and relevance: In this double-blind, placebo-controlled, randomized trial we showed that combination treatment with sulindac and erlotinib compared with placebo resulted in significantly lower colorectal polyp burden after 6 months of treatment. There was a reduction in polyp burden in both those with an entire colorectum and those with only a rectal pouch or rectum.

Trial registration: clinicaltrials.gov Identifier: NCT01187901.

Figure 1.. Study Flow Diagram

IPAA indicates ileal pouch anal anastomosis; IRA, ileo-rectum.

Figure 2.. Box Plot of Percent Change in Polyps From Baseline to 6 Months

Circles indicate observed data points. The box plot lines correspond from bottom of box to top: 25th percentile, median percentile, 75th percentile. The whiskers extend to the minimum and maximum values.