TG01/GM-CSF and adjuvant gemcitabine in patients with resected RAS-mutant adenocarcinoma of the pancreas (CT TG01-01): a single-arm, phase 1/2 trial

Background: TG01 is the first cancer immunotherapy targeting KRAS oncogenic mutations. This study assessed the safety and efficacy of TG01/GM-CSF in patients with resected pancreatic adenocarcinoma.

Methods: Patients with stage I or II pancreatic adenocarcinoma who had undergone surgical resection (R0 or R1) received adjuvant gemcitabine with TG01/GM-CSF using two schedules of vaccination. Immune response was defined as a positive delayed-type hypersensitivity (DTH) response and/or positive T-cell proliferation assay.

Results: Thirty-two patients were enrolled between February 2013 and May 2016. Nineteen were treated with the high antigen burden, with four serious adverse reactions considered possibly related to TG01 treatment, including three allergic reactions. On this basis, a further 13 patients received a modified vaccination schedule with reduced antigen burden, with no serious adverse events related to TG01. Ninety-five percent patients in the main cohort and 92% in the modified cohort had a positive immune response. Median overall survival (OS) was 33.1 months, and median disease-free survival (DFS) was 13.9 months for the main cohort. For the modified cohort, the median OS was 34.3 months and median DFS was 19.5 months.

Conclusions: TG01/GM-CSF with gemcitabine was well tolerated, with high levels of immune activation. OS and DFS compare favourably with published data for adjuvant gemcitabine.

Clinical trial registration: This clinical trial was registered at ClinicalTrials.gov (NCT02261714).