Phanes Therapeutics has signed a clinical supply agreement with BeiGene for assessing a PT199 and tislelizumab combination in a Phase I clinical trial for multiple advanced solid tumours.

The multi-centre Phase I clinical trial has been designed to assess the pharmacodynamics, pharmacokinetics, tolerability, safety, and preliminary efficacy of Phanes’ PT199 alone, as well as in combination with BeiGene’s tislelizumab.

It will be conducted in locally advanced or metastatic solid tumour patients, whose disease has progressed following all available standard therapy or whose condition is intolerable, ineffective, or inappropriate for standard therapy.

Phanes Therapeutics founder and CEO Dr Ming Wang said: “We are excited about the opportunity to evaluate PT199 in combination with tislelizumab for the treatment of solid tumours.

“PT199 is an anti-CD73 monoclonal antibody with a differentiated mechanism of action to counter the immunosuppressive tumour microenvironment in cancer patients.

“The combination of PT199 with tislelizumab provides a new opportunity to assess the strategy to enhance antitumor immune response in patients with advanced or metastatic cancer refractory to previous treatments.”

The differentiated anti-CD73 monoclonal antibody PT199 has been designed to counter the adenosine-mediated immunosuppressive tumour microenvironment (TME).

It completely hinders the enzyme activities of soluble and membrane-bound CD73.

The humanised IgG4 anti-PD-1 monoclonal antibody tislelizumab has been specifically designed to lower the Fc-gamma (Fcγ) receptors binding on macrophages.

This helps the immune cells in the body to detect and fight tumours.

The anti-PD-1 antibody is currently being assessed as a monotherapy and in combination for the treatment of hematologic malignancies and solid tumour.

In October this year, Phanes received approval from the US Food and Drug Administration (FDA) for its Investigational New Drug (IND) application to commence the Phase I clinical trials of antibody PT217 to treat small cell lung cancer (SCLC), as well as other neuroendocrine cancer patients.