MORPHEUS: A phase Ib/II multi-trial platform evaluating the efficacy and safety of cancer immunotherapy (CIT)-based combinations in patients (pts) with gastric or pancreatic cancer.

TPS530Background: CIT has demonstrated significant survival benefits across multiple cancers. Despite remarkable success, only subsets of pts derive clinical benefit from CIT monotherapy. Thus, CIT combinations may be needed to address the mechanisms that allow cancers to escape antitumor immunity. However, a large number of potential combinations would have to be tested to identify an effective CIT combination regimen. The MORPHEUS platform consists of multiple, global, open-label, randomized Phase Ib/II trials designed to assess the impact of CIT combination therapies in pts with different tumor types. The randomized trial designs allow comparison of a single control arm vs multiple CIT combination arms. The trials will aid development of CIT combinations by identifying early signals and have the flexibility to open arms with new CIT combinations and close arms that show minimal clinical activity or unacceptable toxicity. Various CIT combinations that simultaneously enhance immune cell priming and activ...