Press Release

NantKwest Announces Enhanced High-Affinity Activated Natural Killer (haNK) Cell Therapy in Preclinical Studies of HER2 Positive Breast Cancer at Presentation at the San Antonio Breast Cancer Symposium

CULVER CITY, Calif.--(BUSINESS WIRE)--Dec. 12, 2016-- NantKwest Inc. (Nasdaq:NK), a pioneering, next generation, clinical-stage immunotherapy company focused on harnessing the unique power of our immune system using natural killer (NK) cells to treat cancer, infectious diseases and inflammatory diseases, announced that the company presented results from a preclinical study on the company’s high affinity Natural Killer (haNK) cell therapy program at the San Antonio Breast Cancer Symposium (SABCS) in San Antonio, TX, which was held on December 6-10, 2016.

Previous studies have shown that patients with HER2 positive breast cancer who have the high-affinity CD16 receptor that have been treated with Herceptin (trastuzumab) had better clinical outcomes versus those without the high affinity receptor. In this study, in a mouse xenograft model of HER2 positive breast cancer, to enhance the activity of aNK (activated natural killer) cell therapy aNK cells were engineered to express the CD16 high affinity Fc receptor (haNK cells). Study results reported provide further supporting evidence that antibody-dependent cellular cytotoxicity (ADCC) mediated cancer cell killing can be further enhanced through the recognition of the Fc fragment of a therapeutic antibody, in this case Herceptin, and the haNK cell’s CD16 Fc receptor.

“In over 50 patients in a broad range of cancer types, NantKwest’s aNK cell therapy has demonstrated promising indications of efficacy and an excellent safety record,” said Patrick Soon-Shiong, MD, Chairman and CEO of NantKwest. “In this study, haNK cell therapy in combination with Herceptin was highly synergistic, resulting in tumor regression and significantly better efficacy in comparison to either agent alone. This data, highlighting the potential benefit of combining haNK cell therapy with Herceptin in patients with HER2-positive breast cancer, provides further supportive evidence and a solid foundation to fast track this program into human clinical trials.”

Collaborating on the study were research scientists from NantBiosciences, NantCell and NantKwest.

Presentation Summary

  • High-affinity Activated Natural Killer (haNK) Cells Augment Trastuzumab Efficacy in a Mouse Model of HER2-positive Human Metastatic Breast Cancer
  • Abstract #P2-04-1-466
  • Presenter: Shahrooz Rabizadeh, PhD, NantBiosciences Inc., Culver City, CA
  • Thursday, December 8, 2016, 7:30 AM, Room Hall 1

This poster reviews the potential synergistic use of haNK cell therapy in combination with Herceptin (trastuzumab) in patients with HER2-positive breast cancer.

About NantKwest

NantKwest (Nasdaq:NK) is a pioneering, next generation, clinical-stage immunotherapy company focused on harnessing the unique power of our immune system using natural killer (NK) cells to treat cancer, infectious diseases and inflammatory diseases. NK cells are the body’s first line of defense due to the innate ability of NK cells to rapidly identify and destroy cells under stress, such as cancer or virally-infected cells.

NantKwest’s unique NK cell-based platform, with the capacity to grow active killer cells as a biological cancer therapy, has been designed to induce cell death against cancer or infected cells by three different modes of action: (1) Direct killing using activated NK cells (aNK) that release toxic granules directly into the cell through cell to cell contact, (2) Antibody-mediated killing using haNKs, which are NK cells engineered to incorporate a high affinity receptor that binds to an administered antibody, enhancing the cancer cell killing effect of that antibody, and (3) Targeted activated killing using taNKs, which are NK cells engineered to incorporate chimeric antigen receptors (CARs) to target tumor-specific antigens found on the surface of cancer cells.

Our aNK, haNK and taNK platform addresses certain limitations of T cell therapies including the reduction of risk of serious "cytokine storms" reported after T cell therapy. As an “off-the-shelf” therapy, NantKwest's NK cells do not rely on a patient’s own often compromised immune system. In Phase 1 clinical trials in patients with late stage cancer, NantKwest's NK cells have been successfully administered as an outpatient infusion therapy without any reported severe side effects, even at doses of 10 billion cells.

By leveraging an integrated and extensive genomics and transcriptomics discovery and development engine, together with a pipeline of multiple, clinical-stage, immuno-oncology programs that include a Phase 2 trial for a rare form of melanoma and the planned initiation of a clinical trial of NK cells targeted to breast cancer, we believe NantKwest is uniquely positioned to be the premier immunotherapy company and transform medicine by delivering living drugs in a bag and bringing novel NK cell-based therapies to routine clinical care. For more information, please visit http://www.nantkwest.com.

Source: NantKwest Inc.

NantKwest Inc.
Jen Hodson, 562-397-3639
jhodson@nantworks.com