NantKwest Inc. (NSDQ:NK) said yesterday that the FDA approved an Investigational New Drug Application for its natural killer cell therapy phase I clinical study. The company is evaluating its genetically engineered, allogenic natural killer cell therapy in patients with cancer.

The study, which NantKwest touts as the 1st of its kind, will determine the safety of natural killer cell monotherapy given intravenously once a week in as many as 16 patients with metastatic or locally advanced solid tumors.

Other goals of the study include determining an objective response rate, progression-free survival, overall survival and any correlation between tumor molecular profiles and patient outcomes, according to NantKwest.

“We are thrilled to have received notification from the FDA that our 1st haNK cell therapy program has been authorized to proceed into Phase I clinical trials and are focused on moving swiftly to begin this study,” chairman & CEO Dr. Patrick Soon-Shiong said in prepared remarks. “The FDA’s authorization to initiate this clinical trial achieves a significant milestone for NantKwest as we begin clinical investigation of the use of haNK cell therapy for the treatment of cancer in a wide range of cancer types.”

The Culver City, Calif.-based company’s cell therapy is designed to optimize the role that natural killer cells play in mediating immunity, enhancing immune responses and improving anti-tumor responses.

In preclinical studies, the addition of high affinity natural killer cells to various therapeutic antibodies increased tumor cell killing compared to the antibody alone. The company said that its 1st clinical study is designed to provide the required safety data needed to transition to haNK-antibody combination studies.

NK shares were trading at $5.88 per share in morning activity, down -7.9%.