ATP-128

This is a multi-center, non-randomised Phase 1b study to evaluate the safety and tolerability of ATP128 alone or in combination with BI 754091 and of heterologous prime-boost ATP128 + VSV-GP128 in combination with BI 754091.
ATP128 is a self-adjuvanted chimeric recombinant protein vaccine being developed in combination with programmed cell death 1 (PD-1) blockade for the treatment of microsatellite stable (MSS) patients not responding to PD-1 blockade. The PD-1 inhibitor being tested with ATP128 is the BI 754091 (Ezabenlimab) compound which belongs to the human immunoglobulin G4 (IgG4) subclass of antibodies.
VSV-GP is a recombinant chimeric vesicular stomatitis virus (VSV, Indiana strain Rhabdoviridae) which carries the envelope glycoprotein (GP) of the visceral non neurotropic WE-HPI strain of the Lymphocytic choriomeningitis virus (LCMV, Arenaviridae) instead of the native VSV glycoprotein (G) and is developed as integral part of the prime-boost regimen together with ATP128.
The Sponsor plans to enrol 96 patients with histologically or cytologically confirmed stage IV colorectal cancer coming form three different patient populations:
* Cohort 1a: 6 patients with stage IV colorectal cancer (CRC) having failed standard of care (SoC) therapies
* Cohorts 1b, 2a, 2c: 30 patients with stage IV microsatellite stable/mismatch repair-proficient (MSS/MMRp) CRC being in stable disease (SD) or partial response (PR) after first line of SoC (4-6 months duration at minimum)
* Cohorts 2b, 4b: 30 patients with stage IV MSS/MMRp liver-limited disease
Patients eligible for this study will be enrolled in one of the 8 cohorts depending on their disease:
* Patients in Cohort 1a will receive ATP128 as single agent
* Patients in Cohorts 1b, 2a, 2b, 2c will receive ATP128 in combination with BI 754091
* Patients in Cohorts 3, 4a, 4b will receive ATP128 and VSV-GP128 in combination with BI 754091