Korean company Hanmi Pharmaceutical has signed a licence and collaboration agreement with US-based Rapt Therapeutics for a cancer drug candidate, FLX475, in Asia.

The deal provides Hanmi with exclusive rights to develop and commercialise the cancer asset in South Korea and China, including Taiwan and Hong Kong.

FLX475 is an oral, small molecule antagonist of C-C Motif Chemokine Receptor 4 (CCR4). It selectively inhibits the passage of regulatory T cells (Treg) into tumours and not healthy tissues.

The mechanism is expected to restore natural anti-tumour response and boost the different standard and immune-based treatments, including chemotherapy, radiation and checkpoint inhibitors.

Currently, Rapt Therapeutics is conducting a Phase I / II clinical trial of the drug candidate as monotherapy and in combination with pembrolizumab for the treatment of ‘charged’ tumours.

Data from the Phase II part of the study are set to be available in the first half of next year.

The deal is intended to boost Hanmi’s immuno-oncology portfolio with the addition of FLX475, while RAPT will be able to enter the Asian market.

Hanmi Pharmaceutical CEO Se-Chang Kwon said: “We are actively building our immuno-oncology portfolio, and see FLX475 as a potential keystone in our effort to deliver new safe and effective cancer therapeutics to patients who need them.

“This compound complements our current product portfolio and has the potential to address a large and growing population of patients suffering from cancers that are prevalent in Asian countries.”

Under the agreement, Hanmi will pay Rapt Therapeutics $10m in terms of upfront and near-term milestone payments.

Furthermore, Rapt Therapeutics will get up to $48m in development milestones and up to $60m in sales milestones. The company is also eligible for royalties on sales of FLX475 in the stated regions.

Hanmi will support Rapt Therapeutics’ Phase I / II study via its clinical trial infrastructure in Korea and China. The company will also perform a Phase II study of FLX475 in gastric cancer patients in these countries.