Eucure Biopharma, a Biocytogen subsidiary, has dosed the first subject in Phase I clinical trial of its YH003 along with YH001 and pembrolizumab to treat advanced solid tumour patients in Australia.

YH003 is a humanised IgG2 anti-CD40 monoclonal antibody (mAb), while YH001 and pembrolizumab are anti-CTLA-4 and anti-PD-1 mAbs, respectively.

The open-label, dose-escalation trial will analyse the safety, tolerability and efficacy of the triple mAb combination of YH003, YH001 and pembrolizumab in advanced solid tumour patients. 

Furthermore, the trial will assess YH003’s pharmacokinetics and immunogenicity.

YH003 was found to offer robust anti-tumour effects against multiple tumour models, when used as a monotherapy or along with anti-PD-1 mAb drugs, in Biocytogen’s humanised CD40 mice, without showing hepatotoxicity or other toxicities. 

In addition, YH003 substantially boosted the infiltration of anti-tumour T cells into tumours, pharmacodynamic studies in mice showed.

Eucure Biopharma chairman and CEO Dr Yuelei Shen said: “Previous Phase I clinical trials of YH003/Toripalimab (anti-PD-1 mAb) combination therapy and YH001/Toripalimab combination therapy indicate desirable safety profiles and preliminary efficacy for both products. 

“The combination of CTLA-4, PD-1 and CD40 mAbs is based on their different but complementary biological mechanisms; we hope that the three-drug combination study can further strengthen the antitumour efficacy to benefit patients.”

In March last year, the company dosed the first subject in a multi-regional Phase I trial of YH002 plus YH001 in Australia. 

Eucure intends to carry out this open-label, dose-escalation trial in Australia and China to assess the safety, tolerability and initial efficacy of YH002 plus YH001 in advanced solid tumour patients.