NantKwest Reports No Dose-Limiting Toxicities in Early Evaluation of Natural Killer Cell Therapy

NEW YORK – NantKwest on Monday announced promising Phase I safety data for its immunotherapy targeting PD-L1 expressing tumors. 

The drug candidate, QUILT-3.064, is being evaluated for safety and primary efficacy in six patients with solid tumors expressing PD-L1, a protein that can play a role in eliciting an immune response against cancer cells. 

The study start date was July 18, and as of Dec. 2, no dose-limiting toxicity or adverse immune reactions were observed in the six outpatient subjects with locally advanced or metastatic solid tumors. 

QUILT-3.064 is a PD-L1.t-haNK cell therapy "that can rapidly deliver treatment to patients in an outpatient setting while avoiding the extensive manufacturing delays associated with autologous CAR-T therapies," NantKwest CEO Patrick Soon-Shiong said in a statement. NantKwest is also interested in exploring the effects of PD-L1.t-haNK in combination with other therapies such as ImmunityBio’s N-803, an IL-15 superagonist that is designed to stimulate the activation and proliferation of the patient’s own natural killer cells to treat cancer.  

Los Angeles-based NantKwest is a clinical-stage immunotherapy company and is among the many technology firms under Soon-Shiong's umbrella organization NantWorks. The company aims to create precision cancer treatments using natural killer cells designed to recognize and kill cancer cells. QUILT-3.064 specifically relies on PD-L1.t-haNK natural killer cells designed to target monoclonal antibodies and PD-L1-expressing tumor cells. 

"We are highly encouraged by the early safety results with PD-L1.t-haNK in a patient population with advanced, difficult to treat solid tumors," John Lee, clinical senior VP at NantKwest, said in a statement. "NantKwest’s approach has been designed to overcome the challenges and limitations typically seen when treating solid tumors with CAR-T and other immunotherapy approaches."

This is a two-part study in which the first phase will evaluate escalating doses of the therapy, and the second phase will explore the safety and efficacy of the recommended dose. Researchers will also explore secondary endpoints in the study, including objective response rate, progression-free survival, and overall survival.