Verastem Oncology partner CSPC Pharmaceutical Group has commenced the dosing of patients in a Chinese bridging study of Copiktra (duvelisib) in relapsed or refractory follicular lymphoma (FL) patients.

Copiktra is an oral phosphoinositide 3-kinase (PI3K) inhibitor. It is said to be the first dual inhibitor of PI3K-delta and PI3K-gamma approved in the US.

PI3K-delta and PI3K-gamma are the enzymes associated with the growth and survival of malignant B-cells. PI3K signalling is linked to malignant B-cell proliferation, as well as tumour microenvironment formation and maintenance.

Verastem Oncology CEO Brian Stuglik said: “Building on CSPC’s strong track record of successfully developing and commercialising oncology products in China, we are pleased that this CSPC trial is now underway as they work to provide a new option for patients with follicular lymphoma in China, where there are limited options for this difficult-to-treat disease.

“The first patient dosed in this trial is a critical step in our mission to bring Copiktra to patients around the world.”

Verastem signed an exclusive licensing agreement in September 2018, under which CSPC agreed to develop and commercialise the drug across all oncology indications in China.

The Chinese bridging study will assess the safety and anti-tumour activity of duvelisib. It will be based on the safety and efficacy data gathered in Verastem’s Phase II DYNAMO study.

Results from the bridging study will support a regulatory submission of the drug to treat relapsed or refractory FL in China.

In the US, the drug holds approval for adults with relapsed or refractory chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL) following at least two previous therapies.

Verastem is also developing the drug for peripheral T-cell lymphoma (PTCL). Copiktra has fast-track designation in this indication in the US.