Blood Cancer Phase I NK Cell Clinical Trial Shows Durable Complete Responses

An immunotherapy called natural killer (NK) cells  can be used with your own NK cells (autologous) or a donor's NK cells (allogeneic). Autologous NK cell therapy can treat cancer, but is limited by patient-specific variations in strength and how much they can expand. In contrast, donor NK cells can overcome many of these limitations.

Researchers in Toronto, Canada at the Princess Margaret Cancer Centre ran a Phase I clinical trial for 12 patients who had completed stem cell transplant and had either relapsed multiple myeloma or Hodgkins lymphoma. Using irradiated NK-92 cells, the study was designed to watch for safety, identify proper dosing levels and assess how effective the treatment was.

Patients were treated on three different dose levels  (1 × 109 cells/m2, 3 × 109 cells/m2 and 5 × 109 cells/m2), given on day 1, 3 and 5 for a planned total of six monthly cycles.

The treatment was well tolerated, with minor toxicities of infusion related reactions (fever, chills, nausea and fatigue). Two patients achieved a complete response (Hodgkin lymphoma and multiple myeloma), two patients had minor responses and one had clinical improvement on the trial. The data demonstrated continuing evidence of safety and efficacy, with an overall response rate of 42% and no evidence of grade 3 or 4 adverse events from the infusions. Two out of the 12 patients in study with demonstrated durable complete response with single agent aNK therapy, and remain free of disease to date, 10 years and 2 years respectively.

Study authors determined that the NK cells could be administered at very high doses with minimal toxicity in patients with refractory blood cancers, who had relapsed after transplant. They concluded that high dose NK-92 therapy is safe, shows some evidence of efficacy in patients with refractory blood cancers and warrants further clinical investigation.

NantKwest is the company developing the NK cell therapy platform. It is being developed as an allogeneic, off-the-shelf therapy, offering a potent, standardized, uniform and consistent product, further optimized to enhance the key capability of natural killer cells to directly target and kill cancer cells. It is also in Phase II clinical trials in Merkel cell carcinoma.

The company's unique NK cell-based platform uses three methods 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. 

Dr. Patrick Soon-Shiong, Chairman and CEO of NantKwest said:

“We believe our product portfolio of novel off-the-shelf NK cell therapies is unique in offering a more uniform, consistent and optimized product potency with minimal toxicity and we remain focused on translating these unique advantages to patient care as rapidly as possible.”

Find the full study in Oncotarget here.

Natural Killer Cell Myeloma Clinical Trials

Click the studies below to find myeloma-specific NK cell clinical trials.

• A Dose Escalation Phase I Study to Assess the Safety and Clinical Activity of Multiple Cancer Indications
• A Safety Study of Human Cord Blood Derived, Culture-expanded, Natural Killer Cell (PNK-007) Infusion With Subcutaneous Recombinant Human Interleukin-2 (rhIL-2) Following Autologous Stem Cell Transplant for Multiple Myeloma (MM)
• All Natural Killer Cell Trials