Safety and Efficacy of Avelumab in Small Bowel Adenocarcinoma.

Journal Article (Journal Article)

INTRODUCTION: Small bowel adenocarcinomas (SBAs) are rare and frequently treated like large intestinal adenocarcinomas. However, SBAs have a very different microenvironment and could respond differently to the same therapies. Our previous data suggested that SBAs might benefit from targeting the PD-1/PD-L1 axis based on PD-L1 staining in almost 50% of SBA tissue samples tested. Thus, we designed a phase 2 study to explore safety and efficacy of avelumab in SBA. PATIENTS AND METHODS: Patients with advanced or metastatic disease were enrolled; ampullary tumors were considered part of the duodenum and allowed. Prior PD-1/PD-L1 inhibition was not allowed. Avelumab (10 mg/kg) was given every 2 weeks, and imaging was performed every 8 weeks. Primary endpoint was response rate. RESULTS: Eight patients (n = 5, small intestine; n = 3, ampullary) were enrolled, with a majority (88%) being male and a median age of 61 years. Of 7 efficacy-evaluable patients, 2 (29%) experienced partial responses; stable disease occurred in 3 additional patients (71%). Median progression-free survival was 3.35 months. Most frequent, related toxicities were anemia, fatigue, and infusion-related reaction (25% each), mostly grade ≤2; grade 3 hypokalemia and hyponatremia occurred in one patient, and another reported grade 4 diabetic ketoacidosis. CONCLUSIONS: Despite the observed benefit, accrual was slower than expected and the study was closed early due to feasibility. A general clinic observation was that patients were receiving immunotherapy off-label as the availability of these agents increased. Off-label availability and disease rarity were likely drivers of insufficient accrual.

Full Text

Duke Authors

Cited Authors

  • Cardin, DB; Gilbert, J; Whisenant, JG; Ayers, GD; Jalikis, F; Dahlman, KB; O'Neal, JF; Revetta, F; Shi, C; Berlin, J

Published Date

  • March 24, 2022

Published In

PubMed ID

  • 35450836

Electronic International Standard Serial Number (EISSN)

  • 1938-0674

Digital Object Identifier (DOI)

  • 10.1016/j.clcc.2022.03.003

Language

  • eng

Conference Location

  • United States