NKTR-214

About NKTR-214, Nektar's Lead Immuno-oncology Candidate

NKTR-214 is a CD122-biased agonist designed to stimulate the patient's own immune system to fight cancer. NKTR-214 is designed to grow specific cancer-killing T cells and natural killer (NK) cell populations in the body which fight cancer, which are known as endogenous tumor-infiltrating lymphocytes (TILs). NKTR-214 stimulates these cancer-killing immune cells in the body by targeting CD122 specific receptors found on the surface of these immune cells, known as CD8+ effector T cells and Natural Killer (NK) cells. CD122, which is also known as the Interleukin-2 receptor beta subunit, is a key signaling receptor that is known to increase proliferation of these effector T cells.¹ In clinical and preclinical studies, treatment with NKTR-214 resulted in expansion of these cells and mobilization into the tumor micro-environment.^2,3 NKTR-214 has an antibody-like dosing regimen similar to the existing checkpoint inhibitor class of approved medicines.

In preclinical studies, NKTR-214 demonstrated a mean ratio of 450:1 within the tumor micro-environment of CD8-positive effector T cells, which promote tumor destruction, compared with CD4-positive regulatory T cells, which are a type of cell that can suppress tumor-killing T cells.²  Furthermore, a single dose of NKTR-214 resulted in a 500-fold AUC exposure within the tumor compared with an equivalent dose of the existing IL-2 therapy, enabling, for the first time, an antibody-like dosing regimen for a cytokine.² In dosing studies in non-human primates, there was no evidence of severe side effects such as low blood pressure or vascular leak syndrome with NKTR-214 at predicted clinical therapeutic doses.² NKTR-214 has a range of potential uses against multiple tumor types, including melanoma (the most serious type of skin cancer), kidney cancer and non-small cell lung cancer (the most common form of lung cancer).

A Phase 1 study evaluating NKTR-214 as a single agent in patients with locally recurrent or metastatic solid tumors including melanoma, renal cell carcinoma (RCC), bladder, colorectal and other solid tumors is complete. Results from this Phase 1 trial were presented at the 2017 ASCO Annual Meeting and showed encouraging evidence of anti-tumor activity, and a favorable safety and tolerability profile. (Abstract 2545/Poster 37)

In February 2018, Nektar and Bristol-Myers Squibb entered into a global development and commercialization agreement to evaluate the full potential of NKTR-214 plus Opdivo® (nivolumab) in more than 20 indications in 9 tumor types including melanoma, renal cell carcinoma, non-small cell lung cancer, bladder and triple negative breast cancer.

In April 2018, Nektar announced a new clinical collaboration agreement with Takeda to evaluate NKTR-214 in combination with TAK-659, a dual SYK and FLT-3 inhibitor in liquid and solid tumors with the first of these studies expected to begin in the second half of 2018 in patients with Non-Hodgkin Lymphoma. 

In May 2018, Nektar announced a clinical collaboration with Syndax Pharmaceuticals to evaluate NKTR-214 in combination with entinostat, an oral, small molecule Class 1 specific HDAC inhibitor, in patients with metastatic melanoma who have previously progressed on treatment with an anti-PD-1 agent.

Additional development plans for NKTR-214 include combination studies with additional checkpoint inhibitors, cell therapies and vaccines.

About the PIVOT Phase 1/2 Program: NKTR-214 in combination with OPDIVO^® (nivolumab)

The PIVOT Phase 1/2 program is a dose escalation and expansion study of NKTR-214 when administered in combination with nivolumab in patients with melanoma, renal cell carcinoma, non-small cell lung cancer (NSCLC), urothelial carcinoma, or triple negative breast cancer. The dose escalation stage of the study enrolled 38 patients and evaluated the safety and efficacy profile of the combination and the recommended phase 2 dose was established. The expansion stage of the PIVOT program is underway to evaluate the safety and efficacy of combining NKTR-214 with nivolumab in approximately 330 patients who are either immuno-oncology (I-O) therapy naïve or anti-PD-1 or anti-PD-L1 relapsed/refractory. The expansion cohorts in the PIVOT program include five tumor types and thirteen indications, including first and second-line melanoma, first and second-line renal cell carcinoma, first and second-line NSCLC, first and third-line urothelial carcinoma, and first and second-line triple negative breast cancer. For more information, please visit clinicaltrials.gov and search NCT02983045.

About the PROPEL Phase 1/2 Program: NKTR-214 in combination with TECENTRIQ^® (atezolizumab) or KEYTRUDA^® (pembrolizumab)

The dose escalation stage of the PROPEL program will determine the recommended Phase 2 dose of NKTR-214 administered in combination with anti-PD-L1 agent, atezolizumab or anti-PD-1 agent, pembrolizumab. The study will evaluate the clinical benefit, safety and tolerability of combining NKTR-214 with atezolizumab or pembrolizumab and will enroll patients into two separate arms concurrently. The first arm will evaluate an every three-week dose regimen of NKTR-214 in combination with atezolizumab in up to 30 patients with urothelial bladder cancer in approved treatment settings of atezolizumab. The second arm will evaluate an every three-week dose regimen of NKTR-214 in combination with pembrolizumab in up to 50 patients with melanoma and and non-small cell lung cancer in approved treatment settings of pembrolizumab. For more information, please visit clinicaltrials.gov and search NCT03138889. 

About the REVEAL Phase 1/2 Program: NKTR-214 in combination with NKTR-262

REVEAL is a Nektar-sponsored, open-label, multicenter, dose escalation and dose expansion study of NKTR-262 administered as intratumoral injections in combination with NKTR-214 administered as an IV infusion systemically (doublet). The study also may evaluate the doublet combination with nivolumab (triplet). During the dose escalation phases, recommended Phase 2 dose (RP2D) regimens of the doublet and/or triplet combinations will be established.  Following dose escalation, the dose expansion phase will evaluate the doublet and/or triplet combinations in up to 350 patients who have been diagnosed with a range of locally advanced or metastatic cancers including: melanoma, Merkel cell carcinoma, triple-negative breast cancer, ovarian cancer, renal cell carcinoma, colorectal cancer, urothelial carcinoma, or sarcoma. For more information, please visit clinicaltrials.gov and search NCT03435640.

References

1.     Boyman, J., et al., Nature Reviews Immunology, 2012, 12, 180-190.

2.     Charych, D., et al., Clin Can Res; 22(3) February 1, 2016

3.     Diab, A., et al., Journal for ImmunoTherapy of Cancer 2016, 4(Suppl 1):P369