NantKwest (NK) said Tuesday fresh data in a trial of patients who have received off-the-shelf aNK and/or haNK natural killer cell therapy in combination with immunotherapeutic agents in advanced solid tumors show “durable complete responses in 5 out of 35 patients with highly refractory late-stage cancers across multiple tumor types.”

Shares jumped more than 5% during pre-market trade.

All the five patients remain alive to date, ranging from four to 24 months from the onset of response, the company said.

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“These early signals of efficacy have now provided us a pathway to the development of registration trials across triple negative breast cell and Merkel cell carcinoma,” said NantKwest Chief Executive Patrick Soon-Shiong in a statement.

Separately, the company said the Food and Drug Administration has authorized a trial utilizing CD19 T-haNK to treat refractory diffuse large B-cell lymphoma as well as its investigational new drug filing of PD-L1 T-haNK for refractory solid tumors.