A Study of a Personalized Cancer Vaccine Targeting Shared Neoantigens

Colorectal Cancer Clinical Trial

Official title: A Phase 1/2 Study of GRT-C903/GRT-R904, a Vaccine Targeting Shared Neoantigens, in Combination With Immune Checkpoint Blockade for Patients With Advanced Solid Tumors

Status Completed

Clinical Trial Summary

The purpose of this study is to evaluate the dose, safety, immunogenicity and early clinical activity of GRT-C903 and GRT-R904, a neoantigen-based therapeutic cancer vaccine, in combination with immune checkpoint blockade, in patients with advanced or metastatic non-small cell lung cancer, microsatellite stable colorectal cancer, pancreatic cancer, and shared neoantigen-positive tumors. Based on the Phase 1 data, an updated vaccine candidate (SLATE-KRAS or version 2) was developed that removed 16 of the 20 mutations included in the original vaccine (version 1) and solely targets KRAS mutations.

Clinical Trial Description

Tumors harboring non-synonymous deoxyribonucleic acid (DNA) mutations can present peptides containing these mutations as non-self antigens in the context of HLA on the tumor cell surface. A fraction of mutated peptides result in neoantigens capable of generating T-cell responses that exclusively target tumor cells. Some of these tumor-specific neoantigens are known or expected to be common across a subset of patients and are called shared neoantigens. This study aims to target shared neoantigens using a heterologous prime/boost therapeutic vaccine approach (GRT-C903 first followed by GRT-R904) in combination with checkpoint blockade to stimulate an immune response. This study will explore the safety and early clinical activity of this neoantigen-based immunotherapy intended to induce T-cell responses specific for the shared neoantigens contained within the therapeutic vaccine. Phase 1 will test multiple doses and combinations with checkpoint blockade and Phase 2 will test for early signs of clinical activity using a vaccine regimen based on Phase 1 data. ;

Related Conditions & MeSH terms

• Colorectal Cancer
• Neoplasms
• Non-Small Cell Lung Cancer
• Pancreatic Cancer
• Shared Neoantigen-Positive Solid Tumors
• Solid Tumor

• NCT number: NCT03953235
• Study type: Interventional
• Source: Gritstone bio, Inc.
• Status: Completed
• Phase: Phase 1/Phase 2
• Start date: July 18, 2019
• Completion date: March 10, 2023