The US Food and Drug Administration (FDA) has awarded breakthrough therapy designation for Nektar Therapeutics’ bempegaldesleukin (NKTR-214) in combination with Bristol-Myers Squibb (BMS)’s Opdivo (nivolumab) to treat melanoma.

The combination is intended for treatment-naïve patients with unresectable or metastatic melanoma.

Bempegaldesleukin is an investigational agonist of CD122-preferential IL-2 pathway.

The immuno-oncology candidate is meant to trigger activation and proliferation of CD8+ effector T-cells and natural killer (NK) cells that act against cancer.

Nektar Therapeutics noted that the breakthrough therapy designation for the combination is based on data from metastatic melanoma cohort in the ongoing Phase I/II PIVOT-02 clinical trial.

Data at median follow-up of 12.7 months revealed an objective response rate (ORR) of 53% in efficacy-evaluable patients. Median time to response was observed to be two months.

In addition, a Phase III study is further assessing bempegaldesleukin plus nivolumab, compared to nivolumab alone, in first-line advanced melanoma patients.

Nektar Therapeutics research and development senior vice-president and chief R&D officer Dr Stephen Doberstein said: “In collaboration with our partner Bristol-Myers Squibb, we plan to work closely with the FDA as we continue to advance our development program of bempegaldesleukin in combination with nivolumab in advanced melanoma patients.

“Our teams are encouraged by the deepening of responses we observed in patients with previously untreated advanced melanoma who received the doublet therapy in our PIVOT-02 study.”

Last February, Nektar Therapeutics and BMS signed a deal valued up to $3.6bn for strategic development and commercialisation of bempegaldesleukin.

Under the terms of the deal, BMS has an exclusive development option to evaluate NKTR-214 in combination with its Opdivo (nivolumab) and Yervoy (ipilimumab) across 20 indications.