On June 6, 2016 Threshold Pharmaceuticals, Inc. (NASDAQ:THLD) reported multiple presentations on clinical trials on its hypoxia-activated prodrugs, evofosfamide and tarloxotinib at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting being held June 3 through 7, 2016 in Chicago, Ill (Press release, Threshold Pharmaceuticals, JUN 6, 2016, View Source [SID:1234513086]).

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Today, Threshold presented additional data from its analysis of the randomized, double-blind Phase 3 MAESTRO clinical trial of evofosfamide (TH-302) in combination with gemcitabine in previously untreated patients with metastatic or locally advanced unresectable pancreatic ductal adenocarcinoma conducted by Merck KGaA. A meaningful improvement in overall survival was reported for the subgroup of 123 Asian patients enrolled at Japanese and South Korean sites in which the risk of death was reduced by 48 percent for patients on the treatment arm compared to patients on the control arm with an associated stratified hazard ratio of 0.52 (95% CI: 0.32 – 0.85). The patients from Asia also had significant improvements in PFS, objective response rates, and reductions in the pancreatic cancer biomarker, CA19-9 (abstract 4007). As previously reported in January 2016, the primary efficacy endpoint of this study of overall survival narrowly missed statistical significance based on specified intent-to-treat analysis while showing improvements in secondary efficacy endpoints of progression-free survival (PFS) and response.

On June 4, 2016, the following posters were displayed:

Randomized, Double-Blind, Placebo-Controlled Trial of Evofosfamide and Pemetrexed in Second Line Advanced Non-Squamous Non-Small Cell Lung Cancer. Csoszi et al. (abstract 9075).

As reported in January 2016, the study was stopped early based on a futility analysis of overall survival conducted by the study Data and Safety Monitoring Board (DSMB). The study enrolled 265 patients of a planned 440 patients. The response rate with evofosfamide plus pemetrexed was 18.0 percent and significantly higher compared to 8.1 percent with placebo plus pemetrexed. The median PFS with evofosfamide plus pemetrexed was 4.5 months (95% CI: 4.0 to 6.4 months) and significantly higher compared to 2.9 (95% CI: 2.6 to 4.1) months with placebo plus pemetrexed. Hematologic toxicity was greater in the evofosfamide plus pemetrexed arm, while non-hematologic toxicity was similar across treatment arms. No new safety signals were identified.

Evofosfamide combined with gemcitabine/nab-paclitaxel in patients with previously untreated locally advanced or metastatic pancreatic adenocarcinoma (PAC): results of a phase I trial. Borad et al. (abstract 4114).

Nineteen patients were treated for a median of 6 cycles. The maximum tolerated dose of evofosfamide was established at 340 mg/m2 in combination with 800 mg/m2 gemcitabine and 100 mg/m2 nab-paclitaxel. No new safety signals were identified with myelosuppression being the primary dose limiting toxicity. The best response rate was 53 percent and the confirmed response rate was 37 percent.

Two additional trials-in-progress posters were also displayed:

A Phase 2 Study of Tarloxotinib Bromide (TRLX) in Patients with Recurrant or Metastatic Squamous Cell Carcinoma of the Head and Neck (SCCHN) or Skin (SCCS).
Rischin et al. (abstract TPS6105)

A Phase 2 Study (NCT02454842) of Tarloxotinib Bromide (TH-4000) in Patients with EGFR Mutant, T790M-Negative, Advanced NSCLC Progressing on an EGFR TKI.
Liu et al. (abstract TPS9100)

Copies of the posters may be obtained from Threshold’s website, www.thresholdpharm.com, under Scientific Publications.

About Evofosfamide
Evofosfamide (previously known as TH-302) is an investigational hypoxia-activated prodrug of a bis-alkylating agent that is preferentially activated under severe hypoxic tumor conditions, a feature of many solid tumors. Areas of low oxygen levels (hypoxia) in solid tumors are due to insufficient blood vessel supply. Similarly, the bone marrow of patients with hematological malignancies has also been shown, in some cases, to be severely hypoxic. On December 6, 2015, the Company announced the outcomes of two Phase 3 studies (MAESTRO and TH-CR-406/SARC021) of evofosfamide stating that neither study met its primary endpoint.

About Tarloxotinib Bromide
Tarloxotinib bromide (the proposed International Nonproprietary Name, previously known as TH-4000), or "tarloxotinib", is a prodrug designed to selectively release a covalent (irreversible) EGFR tyrosine kinase inhibitor under severe hypoxia, a feature of many solid tumors. Accordingly, tarloxotinib has the potential to effectively shut down aberrant EGFR signaling in a tumor-selective manner, thus potentially avoiding or reducing the systemic side effects associated with currently available EGFR tyrosine kinase inhibitors. Tarloxotinib is currently being evaluated in two Phase 2 proof-of-concept trials: one for the treatment of patients with mutant EGFR-positive, T790M-negative advanced non-small cell lung cancer progressing on an EGFR tyrosine kinase inhibitor, and the other for patients with recurrent or metastatic squamous cell carcinomas of the head and neck or skin. Threshold licensed exclusive worldwide rights to tarloxotinib from the University of Auckland, New Zealand, in September 2014.

On June 6, 2016 Stemline Therapeutics, Inc. (Nasdaq:STML) reported that Ivan Bergstein, M.D., Stemline’s CEO, will present at the Jefferies 2016 Healthcare Conference on Wednesday, June 8, 2016 at 10:00 AM ET (Press release, Stemline Therapeutics, JUN 6, 2016, View Source [SID:1234513078]). During the presentation, Dr. Bergstein will discuss the SL-401 Phase 2 blastic plasmacytoid dendritic cell neoplasm (BPDCN) data presented on June 4th at the 2016 ASCO (Free ASCO Whitepaper) conference. He will also review next steps for the SL-401 program as well as provide updates on the company’s overall pipeline. A live webcast of the presentation can be viewed on the company’s website at www.stemline.com.

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On June 6, 2016 Merck KGaA, Darmstadt, Germany, and Pfizer (NYSE: PFE) reported results from the first pivotal, international, multicenter, open-label, Phase II study of avelumab*, which showed a 31.8% objective response rate (ORR) (28 of 88 patients; 95.9% CI: 21.9–43.1%†), in the pre-planned primary analysis of the study, and a manageable safety profile in patients with metastatic Merkel cell carcinoma (MCC) who were treated with avelumab in second or subsequent lines of therapy (Press release, Pfizer, JUN 6, 2016, View Source [SID:1234513077]). Tumor responses were rapid, with 78.6% of patients (22 of 28) responding within 7 weeks of starting treatment, and durable, with 82.1% of patients (23 of 28) still responding at the time of analysis. No unexpected safety signals were reported. These data will be reported today during an oral presentation at the 52nd American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago, IL.

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"To see a tumor response in almost a third of patients in this trial, and for the majority to keep responding after six months, represents a potential breakthrough for this challenging disease," said lead investigator Howard L. Kaufman, M.D., FACS, Rutgers Cancer Institute of New Jersey, USA. "Currently, the only treatment option available for advanced stages of this aggressive type of skin cancer is chemotherapy, where the response rates are not adequate or durable."

Metastatic MCC has a poor prognosis with less than 20% of patients surviving longer than five years.1 Although chemotherapy is considered a second-line treatment option for metastatic MCC, it is not a standard of care. Current guidelines recommend that these patients participate in clinical trials.2

"This is an important milestone for us as this is the largest data set of any anti-PD-L1 or anti-PD-1 reported to date in this patient population," said Luciano Rossetti, Executive Vice President, Global Head of Research & Development in the biopharma business of Merck KGaA, Darmstadt, Germany, which in the US and Canada operates as EMD Serono. "The clinically meaningful tumor response rate for avelumab in metastatic Merkel cell carcinoma where chemotherapy has failed, reinforces our belief in the promise of this molecule, particularly considering the high unmet need in this disease."

In the trial, eight patients (9.1%) achieved complete responses and 20 patients (22.7%) achieved partial responses. The median duration of response has not been reached (95% CI: 8.3 months – not estimable; range, 2.8–17.5+ months). Tumor responses were seen in patients regardless of the status of certain biomarkers (PD-L1 and Merkel cell polyomavirus). The progression-free survival (PFS) rate at 6 months was 40% (95% CI: 29–50%, estimated by the Kaplan-Meier method). Early data also showed an overall survival (OS) rate at 6 months of 69% (95% CI: 58–78%) and a median OS of 11.3 months (7.5–14.0 months); however, these OS data are still maturing since minimum follow-up was 6 months for inclusion in this analysis. Treatment-related adverse events (AEs) occurred in 62 patients (70.5%); the most common were fatigue (23.9%) and infusion-related reactions (17.0%), all of which were Grade 1 or 2. Grade 3 treatment-related AEs were reported in four patients (4.5%). There were no Grade 4 treatment-related AEs or deaths.

"This has been an exciting ASCO (Free ASCO Whitepaper) for the strategic collaboration between the two companies, between the MCC data and the other encouraging responses observed across a broad range of tumors," said Chris Boshoff, M.D., PhD., Vice President and Head of Early Development, Translational and Immuno-Oncology at Pfizer Oncology. "The clinical benefits for avelumab as a monotherapy in notably hard-to-treat cancers may be amplified even further when combined with other therapies."

Avelumab has received multiple regulatory designations in MCC from the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA), including Orphan Drug (FDA and EMA), Fast Track and Breakthrough status (FDA). There are plans to submit marketing applications for avelumab to regulatory authorities based on these data.

About JAVELIN Merkel 200

JAVELIN Merkel 200 is an international, multicenter, open-label, Phase II study of avelumab conducted in 88 patients with metastatic MCC. Patients in this study were generally elderly (median age was 72.5 years, range 33–88 years) and pre-treated, with at least one line of chemotherapy (one [59.1%], two [29.5%] or three or more [11.4%] previous treatments). Patients received avelumab 10 mg/kg intravenously once every two weeks. The protocol-defined analysis set for efficacy and safety consisted of all patients who received at least one dose of study treatment. The cut-off date for the planned primary analysis was 6 months after start of study treatment of the last patient. The primary endpoint of the study was confirmed best overall response according to RECIST v1.1 and assessed by an independent review committee. Secondary endpoints were duration of response, PFS, OS, response status by RECIST at 6 and 12 months, safety and tolerability, pharmacokinetics, and immunogenicity of avelumab.

*Avelumab is the proposed nonproprietary name for the anti-PD-L1 monoclonal antibody (MSB0010718C). Avelumab is under clinical investigation and has not been proven to be safe and effective. There is no guarantee any product will be approved in the sought-after indication by any health authority worldwide.

†Multiplicity adjustment accounting for interim analysis to achieve overall 95% confidence level.

References

Lemos B, Storer B, Iyer J, et al. Pathologic Nodal Evaluation Improves Prognostic Accuracy in Merkel Cell Carcinoma: Analysis of 5,823 Cases as the Basis of the First Consensus Staging System for this Cancer. Journal of the American Academy of Dermatology. 2010;63:751-761.
NCCN Merkel Cell Carcinoma Guidelines Version I. 2016. Available from: www.nccn.org/professionals/physician_gls/PDF/mcc.pdf (link is external). Accessed April 2016.
About Avelumab

Avelumab (also known as MSB0010718C) is an investigational, fully human anti-PD-L1 IgG1 monoclonal antibody. By inhibiting PD-L1 interactions, avelumab is thought to enable the activation of T-cells and the adaptive immune system. By retaining a native Fc-region, avelumab is thought to potentially engage the innate immune system and induce antibody-dependent cell-mediated cytotoxicity (ADCC). In November 2014, Merck KGaA, Darmstadt, Germany, and Pfizer announced a strategic alliance to co-develop and co-commercialize avelumab.

Alliance between Merck KGaA, Darmstadt, Germany, and Pfizer Inc., New York, US

Immuno-oncology is a top priority for Merck KGaA, Darmstadt, Germany, and Pfizer Inc. The global strategic alliance between Merck KGaA, Darmstadt, Germany, and Pfizer Inc., New York, US, enables the companies to benefit from each other’s strengths and capabilities and further explore the therapeutic potential of avelumab, an investigational anti-PD-L1 antibody initially discovered and developed by Merck KGaA, Darmstadt, Germany. The immuno-oncology alliance will jointly develop and commercialize avelumab and advance Pfizer’s PD-1 antibody. The alliance is focused on developing high-priority international clinical programs to investigate avelumab as a monotherapy, as well as in combination regimens, and is striving to find new ways to treat cancer.

About Merck KGaA, Darmstadt, Germany

All Merck KGaA, Darmstadt, Germany, press releases are distributed by e-mail at the same time they become available on the EMD Group Website. In case you are a resident of the USA or Canada please go to www.emdgroup.com/subscribe (link is external) to register again for your online subscription of this service as our newly introduced geo-targeting requires new links in the email. You may later change your selection or discontinue this service.

Merck KGaA, Darmstadt, Germany, is a leading science and technology company in healthcare, life science and performance materials. Around 50,000 employees work to further develop technologies that improve and enhance life – from biopharmaceutical therapies to treat cancer or multiple sclerosis, cutting-edge systems for scientific research and production, to liquid crystals for smartphones and LCD televisions. In 2015, Merck KGaA, Darmstadt, Germany, generated sales of € 12.85 billion in 66 countries.

Founded in 1668, Merck KGaA, Darmstadt, Germany, is the world’s oldest pharmaceutical and chemical company. The founding family remains the majority owner of the publicly listed corporate group. Merck KGaA, Darmstadt, Germany operates as EMD Serono, MilliporeSigma and EMD Performance Materials in the United States and Canada.

On June 6, 2016 Merck KGaA, Darmstadt, Germany, and Pfizer (NYSE: PFE) reported results from the first pivotal, international, multicenter, open-label, Phase II study of avelumab*, which showed a 31.8% objective response rate (ORR) (28 of 88 patients; 95.9% CI: 21.9–43.1%†), in the pre-planned primary analysis of the study, and a manageable safety profile in patients with metastatic Merkel cell carcinoma (MCC) who were treated with avelumab in second or subsequent lines of therapy (Press release, Pfizer, JUN 6, 2016, View Source [SID:1234513076]). Tumor responses were rapid, with 78.6% of patients (22 of 28) responding within 7 weeks of starting treatment, and durable, with 82.1% of patients (23 of 28) still responding at the time of analysis. No unexpected safety signals were reported. These data will be reported today during an oral presentation at the 52nd American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago, IL.

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Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

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"To see a tumor response in almost a third of patients in this trial, and for the majority to keep responding after six months, represents a potential breakthrough for this challenging disease," said lead investigator Howard L. Kaufman, M.D., FACS, Rutgers Cancer Institute of New Jersey, USA. "Currently, the only treatment option available for advanced stages of this aggressive type of skin cancer is chemotherapy, where the response rates are not adequate or durable."

Metastatic MCC has a poor prognosis with less than 20% of patients surviving longer than five years.1 Although chemotherapy is considered a second-line treatment option for metastatic MCC, it is not a standard of care. Current guidelines recommend that these patients participate in clinical trials.2

"This is an important milestone for us as this is the largest data set of any anti-PD-L1 or anti-PD-1 reported to date in this patient population," said Luciano Rossetti, Executive Vice President, Global Head of Research & Development in the biopharma business of Merck KGaA, Darmstadt, Germany, which in the US and Canada operates as EMD Serono. "The clinically meaningful tumor response rate for avelumab in metastatic Merkel cell carcinoma where chemotherapy has failed, reinforces our belief in the promise of this molecule, particularly considering the high unmet need in this disease."

In the trial, eight patients (9.1%) achieved complete responses and 20 patients (22.7%) achieved partial responses. The median duration of response has not been reached (95% CI: 8.3 months – not estimable; range, 2.8–17.5+ months). Tumor responses were seen in patients regardless of the status of certain biomarkers (PD-L1 and Merkel cell polyomavirus). The progression-free survival (PFS) rate at 6 months was 40% (95% CI: 29–50%, estimated by the Kaplan-Meier method). Early data also showed an overall survival (OS) rate at 6 months of 69% (95% CI: 58–78%) and a median OS of 11.3 months (7.5–14.0 months); however, these OS data are still maturing since minimum follow-up was 6 months for inclusion in this analysis. Treatment-related adverse events (AEs) occurred in 62 patients (70.5%); the most common were fatigue (23.9%) and infusion-related reactions (17.0%), all of which were Grade 1 or 2. Grade 3 treatment-related AEs were reported in four patients (4.5%). There were no Grade 4 treatment-related AEs or deaths.

"This has been an exciting ASCO (Free ASCO Whitepaper) for the strategic collaboration between the two companies, between the MCC data and the other encouraging responses observed across a broad range of tumors," said Chris Boshoff, M.D., PhD., Vice President and Head of Early Development, Translational and Immuno-Oncology at Pfizer Oncology. "The clinical benefits for avelumab as a monotherapy in notably hard-to-treat cancers may be amplified even further when combined with other therapies."

Avelumab has received multiple regulatory designations in MCC from the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA), including Orphan Drug (FDA and EMA), Fast Track and Breakthrough status (FDA). There are plans to submit marketing applications for avelumab to regulatory authorities based on these data.

About JAVELIN Merkel 200

JAVELIN Merkel 200 is an international, multicenter, open-label, Phase II study of avelumab conducted in 88 patients with metastatic MCC. Patients in this study were generally elderly (median age was 72.5 years, range 33–88 years) and pre-treated, with at least one line of chemotherapy (one [59.1%], two [29.5%] or three or more [11.4%] previous treatments). Patients received avelumab 10 mg/kg intravenously once every two weeks. The protocol-defined analysis set for efficacy and safety consisted of all patients who received at least one dose of study treatment. The cut-off date for the planned primary analysis was 6 months after start of study treatment of the last patient. The primary endpoint of the study was confirmed best overall response according to RECIST v1.1 and assessed by an independent review committee. Secondary endpoints were duration of response, PFS, OS, response status by RECIST at 6 and 12 months, safety and tolerability, pharmacokinetics, and immunogenicity of avelumab.

*Avelumab is the proposed nonproprietary name for the anti-PD-L1 monoclonal antibody (MSB0010718C). Avelumab is under clinical investigation and has not been proven to be safe and effective. There is no guarantee any product will be approved in the sought-after indication by any health authority worldwide.

†Multiplicity adjustment accounting for interim analysis to achieve overall 95% confidence level.

References

Lemos B, Storer B, Iyer J, et al. Pathologic Nodal Evaluation Improves Prognostic Accuracy in Merkel Cell Carcinoma: Analysis of 5,823 Cases as the Basis of the First Consensus Staging System for this Cancer. Journal of the American Academy of Dermatology. 2010;63:751-761.
NCCN Merkel Cell Carcinoma Guidelines Version I. 2016. Available from: www.nccn.org/professionals/physician_gls/PDF/mcc.pdf (link is external). Accessed April 2016.
About Avelumab

Avelumab (also known as MSB0010718C) is an investigational, fully human anti-PD-L1 IgG1 monoclonal antibody. By inhibiting PD-L1 interactions, avelumab is thought to enable the activation of T-cells and the adaptive immune system. By retaining a native Fc-region, avelumab is thought to potentially engage the innate immune system and induce antibody-dependent cell-mediated cytotoxicity (ADCC). In November 2014, Merck KGaA, Darmstadt, Germany, and Pfizer announced a strategic alliance to co-develop and co-commercialize avelumab.

Alliance between Merck KGaA, Darmstadt, Germany, and Pfizer Inc., New York, US

Immuno-oncology is a top priority for Merck KGaA, Darmstadt, Germany, and Pfizer Inc. The global strategic alliance between Merck KGaA, Darmstadt, Germany, and Pfizer Inc., New York, US, enables the companies to benefit from each other’s strengths and capabilities and further explore the therapeutic potential of avelumab, an investigational anti-PD-L1 antibody initially discovered and developed by Merck KGaA, Darmstadt, Germany. The immuno-oncology alliance will jointly develop and commercialize avelumab and advance Pfizer’s PD-1 antibody. The alliance is focused on developing high-priority international clinical programs to investigate avelumab as a monotherapy, as well as in combination regimens, and is striving to find new ways to treat cancer.

About Merck KGaA, Darmstadt, Germany

All Merck KGaA, Darmstadt, Germany, press releases are distributed by e-mail at the same time they become available on the EMD Group Website. In case you are a resident of the USA or Canada please go to www.emdgroup.com/subscribe (link is external) to register again for your online subscription of this service as our newly introduced geo-targeting requires new links in the email. You may later change your selection or discontinue this service.

Merck KGaA, Darmstadt, Germany, is a leading science and technology company in healthcare, life science and performance materials. Around 50,000 employees work to further develop technologies that improve and enhance life – from biopharmaceutical therapies to treat cancer or multiple sclerosis, cutting-edge systems for scientific research and production, to liquid crystals for smartphones and LCD televisions. In 2015, Merck KGaA, Darmstadt, Germany, generated sales of € 12.85 billion in 66 countries.

Founded in 1668, Merck KGaA, Darmstadt, Germany, is the world’s oldest pharmaceutical and chemical company. The founding family remains the majority owner of the publicly listed corporate group. Merck KGaA, Darmstadt, Germany operates as EMD Serono, MilliporeSigma and EMD Performance Materials in the United States and Canada.

On June 6, 2016 Nektar Therapeutics (NASDAQ: NKTR) reported new preclinical data for NKTR-214, an immuno-stimulatory CD-122 biased cytokine currently being evaluated in cancer patients with solid tumors in a Phase 1/2 clinical trial being conducted at MD Anderson Cancer Center and Yale Cancer Center (Press release, Nektar Therapeutics, JUN 6, 2016, View Source [SID:1234513074]). The new preclinical data presented demonstrate that treatment with single-agent NKTR-214 mobilizes tumor-killing T cells into colon cancer tumors. In addition, mouse pharmacodynamics data demonstrated that a single dose of NKTR-214 can increase and sustain STAT5 phosphorylation (a marker of IL-2 pathway activation) through one week post-dose. These data were presented at the American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago, IL from June 3-7, 2016.

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"These latest data build upon our growing body of preclinical evidence demonstrating the unique mechanism of NKTR-214," added Jonathan Zalevsky, PhD, Vice President, Biology and Preclinical Development at Nektar Therapeutics. "The studies presented at ASCO (Free ASCO Whitepaper) show that NKTR-214 promotes tumor-killing immune cell accumulation directly in the tumor, providing a mechanistic basis for its significant anti-tumor activity in multiple preclinical tumor models. The ability to grow TILs1 in vivo and replenish the immune system is exceptionally important. We’ve now learned that many human tumors lack sufficient TIL populations and the addition of the NKTR-214 TIL-enhancing MOA could improve the success of many checkpoint inhibitors and other agents, and allow more patients to benefit from immuno-therapy."

In studies previously published for NKTR-214, when mice bearing established breast cancer tumors are treated with NKTR-214 and anti-CTLA4 (a checkpoint inhibitor therapy known as ipilimumab for human treatment), a large proportion of mice become tumor-free. Anti-tumor immune memory was demonstrated when tumor-free mice were re-challenged by implant with a new breast cancer tumor and then found to clear the new tumor, without further therapy. The new data presented at ASCO (Free ASCO Whitepaper) demonstrate that upon re-challenge, there is a rapid expansion of newly proliferative CD8 T cells and particularly CD8 effector memory T cells. Both cell populations were readily detectable in multiple tissues (blood, spleen, and lymph nodes) and likely contribute to the anti-tumor effect observed in these animals. Adoptive transfer studies confirmed the immune-memory effect as transplant of splenocytes from tumor-free mice into naïve recipients provided the ability to resist tumor growth.

"NKTR-214 provides a highly unique immune activation profile that allows it to access the IL-2 pathway without pushing the immune system into pathological overdrive," said Dr. Steve Doberstein, Senior Vice President and Chief Scientific Officer. "NKTR-214’s unique immune-stimulatory profile and antibody-like dosing schedule positions it as a potentially important medicine within the immuno-oncology landscape."

The data presentation at ASCO (Free ASCO Whitepaper) entitled, "Immune memory in nonclinical models after treatment with NKTR-214, an engineered cytokine biased towards expansion of CD8+ T cells in tumor," can be accessed at View Source

NKTR-214 is a CD122-biased agonist designed to stimulate the patient’s own immune system to kill tumor cells by preferentially activating production of specific immune cells which promote tumor killing, including CD8-positive T cells and Natural Killer (NK) cells, within the tumor micro-environment. 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 types of T cells.2

In preclinical studies, NKTR-214 demonstrated a highly favorable mean ratio of 450:1 within the tumor micro-environment of CD8-positive effector T cells relative to regulatory T cells.3 Furthermore, the pro-drug design of NKTR-214 enables an antibody-like dosing regimen for an immuno-stimulatory cytokine.4

About the NKTR-214 Phase 1/2 Clinical Study
A Phase 1/2 clinical study is underway to evaluate NKTR-214 in patients with advanced solid tumors, including melanoma, renal cell carcinoma and non-small cell lung cancer. The first stage of this study, which is expected to be complete in the second half of 2016, is evaluating escalating doses of single-agent NKTR-214 treatment in approximately 20 patients with solid tumors. The primary objective of the first stage of the study is to evaluate the safety and efficacy of NKTR-214 and to identify a recommended Phase 2 dose. In addition, the study will also assess the immunologic effect of NKTR-214 on TILs and other immune cells in both blood and tumor tissue, and it will also include TCR repertoire profiling. Dose expansion cohorts are planned to evaluate NKTR-214 in specific tumor types, including melanoma, renal cell carcinoma and non-small cell lung cancer.

The NKTR-214 clinical study is being conducted initially at two primary investigator sites: MD Anderson Cancer Center under Drs. Patrick Hwu and Adi Diab; and Yale Cancer Center, under Drs. Mario Sznol and Michael Hurwitz. Patients and physicians interested in the ongoing NKTR-214 study can visit the "Clinical Trials" section of www.mdanderson.org using identifier 2015-0573 or visit View Source