Pionyr Immunotherapeutics has commenced subject dosing in its Phase Ib expansion clinical trial of investigational compound PY159 in patients with various types of cancer.
They include ovarian cancer, non-small cell lung cancer, triple-negative breast cancer, HR+HER2- breast cancer, pancreatic ductal adenocarcinoma, colorectal cancer, and head and neck squamous cell carcinomas.
The first subject was dosed in the single-agent ovarian cancer arm.
The trial will assess PY159 given alone and along with pembrolizumab in these tumour patients.
Apart from characterising PY159’s anti-tumour activity, the trial will analyse the safety, tolerability, and pharmacokinetics of the compound.
Further exploratory biomarkers, including the evaluation of TREM1-expression in the immune infiltrate of tumour biopsy samples, will be assessed.
This Phase Ib part of the trial comes after the Phase Ia dose-escalation study.
The multicentred Phase Ia trial in the US assessed the safety and tolerability of PY159 alone and along with pembrolizumab in various solid tumours and selected the recommended dose for expansion to the Phase Ib trial.
An afucosylated humanised monoclonal antibody (mAb), PY159 attaches to human Triggering Receptor Expressed on Myeloid Cells 1 (TREM1).
Pionyr executive vice-president and chief medical officer Leonard Reyno said: “We developed PY159 to target TREM1 and reprogramme myeloid cells within the tumour microenvironment to promote anti-tumour responses, a novel approach to TREM1 biology for anti-tumour drug development.
“In the Phase Ia dose escalation study, PY159 was well tolerated in doses up to ten milligrams per kilogram and showed dose-proportional pharmacokinetics.
“With these conclusions from Phase Ia, we are excited to begin this Phase Ib expansion study with leading clinical sites and investigators.”
In March this year, the company dosed the first subject in the Phase Ib expansion trial of PY314 to treat solid tumours.