Dendreon Publishes New Data in Clinical Cancer Research Correlating the Magnitude of Cytotoxic T Cell Response to PROVENGE® (sipuleucel-T) Treatment with Overall Survival

Findings Expand Understanding of How PROVENGE Activates Killer T Cells to Attack Prostate Cancer Cells

SEAL BEACH, Calif.--()--Dendreon Pharmaceuticals LLC, a commercial-stage biopharmaceutical company and pioneer in the development of immunotherapy, today announced publication of new data in Clinical Cancer Research, a journal of the American Association for Cancer Research, showing that treatment with PROVENGE® (sipuleucel-T) generates killer T cells that target prostatic acid phosphatase (PAP), a protein expressed on the majority of prostate cancer cells. The results of this analysis provide further evidence around the relationship between killer T cell activity and overall survival in men with asymptomatic or minimally symptomatic metastatic castrate-resistant prostate cancer (mCRPC).

“This research suggests the role of sipuleucel-T in the generation of killer T cells following treatment,” said Charles G. Drake, M.D., Ph.D., director of genitourinary oncology at Columbia University Medical Center and senior author. “Importantly, these data suggest how the mechanism of action of sipuleucel-T may, in part, translate into survival benefit for patients.”

To quantify potential cytotoxic T lymphocyte (CTL) activity, cell-surface CD107a expression on PAP-specific CD8+ T cells was measured in samples from a subset of patients enrolled in Dendreon’s STAMP clinical trial (study ID: P11-3) before and after sipuleucel-T treatment. It was observed that T cells were able to recognize and target PAP only after sipuleucel-T treatment, with responses observed at 6 weeks and sustained out to 26 weeks post-treatment. Importantly, the magnitude of the CTL activity at week 26 correlated with increased overall survival, indicating that PROVENGE evokes a memory T cell response that may play a role in the survival benefit of PROVENGE.

“While the IMPACT trial established the survival benefit of sipuleucel-T, the mechanism of action of treatment has not been fully appreciated,” said Bruce A. Brown, M.D., senior vice president, medical, at Dendreon. “This research provides more information about how sipuleucel-T works and – for the first time – correlates the magnitude of killer T cell activity with overall survival.”

Published online yesterday, this study coincides with a related poster presentation at the American Society of Clinical Oncology (ASCO) Annual Meeting along with several presentations that further elucidate sipuleucel-T activity and clinical outcomes:

  • Sat., June 2, 2018, 1:15-4:45 p.m. CT – Poster #254 – Hall A
    Relationship between sipuleucel-T cytolytic T lymphocyte activity and overall survival in patients with metastatic castration resistant prostate cancer. (Drake D, et al)
  • Sat., June 2, 2018, 1:15-4:45 p.m. CT – Poster #268 – Hall A
    Sipuleucel-T overall survival and clinical outcomes by baseline prostate-specific antigen quartiles in patients with metastatic castration-resistant prostate cancer: PROCEED registry. (Sartor O, et al)
  • Sat., June 2, 2018, 1:15-4:45 p.m. CT – Poster #299 – Hall A
    Association of changes in the B-cell receptor repertoire with overall survival after sipuleucel-T treatment for prostate cancer. (Zhang L, et al)

PROVENGE (sipuleucel-T) was the first U.S. Food and Drug Administration (FDA)-approved immunotherapy made from a patient’s own immune cells and remains the only immunotherapy treatment for prostate cancer. More than 30,000 men have been prescribed PROVENGE, and it has been clinically proven to extend life for men with asymptomatic or minimally symptomatic mCRPC.

About PROVENGE® (sipuleucel-T)

PROVENGE is an autologous cellular immunotherapy indicated for the treatment of asymptomatic or minimally symptomatic metastatic castrate-resistant (hormone-refractory) prostate cancer.

IMPORTANT SAFETY INFORMATION

Acute Infusion Reactions: Acute infusion reactions (reported within 1 day of infusion) may occur and include nausea, vomiting, fatigue, fever, rigor or chills, respiratory events (dyspnea, hypoxia, and bronchospasm), syncope, hypotension, hypertension, and tachycardia.

Thromboembolic Events: Thromboembolic events, including deep venous thrombosis and pulmonary embolism, can occur following infusion of PROVENGE. The clinical significance and causal relationship are uncertain. Most patients had multiple risk factors for these events. PROVENGE should be used with caution in patients with risk factors for thromboembolic events.

Vascular Disorders: Cerebrovascular events (hemorrhagic/ischemic strokes and transient ischemic attacks) and cardiovascular disorders (myocardial infarctions) have been reported following infusion of PROVENGE. The clinical significance and causal relationship are uncertain. Most patients had multiple risk factors for these events.

Handling Precautions: PROVENGE is not tested for transmissible infectious diseases.

Concomitant Chemotherapy or Immunosuppressive Therapy: Chemotherapy or immunosuppressive agents (such as systemic corticosteroids) given concurrently with the leukapheresis procedure or PROVENGE has not been studied. Concurrent use of immune-suppressive agents may alter the efficacy and/or safety of PROVENGE.

Adverse Reactions: The most common adverse reactions reported in clinical trials (≥ 15% of patients receiving PROVENGE) were chills, fatigue, fever, back pain, nausea, joint ache, and headache.

For full Prescribing Information, please visit https://www.provengehcp.com/

About Dendreon

Dendreon is a commercial-stage biopharmaceutical company and pioneer in the development of immunotherapy. Dendreon’s flagship product, PROVENGE (sipuleucel-T), was the first FDA-approved immunotherapy made from a patient’s own immune cells. More than 30,000 men with advanced prostate cancer have been prescribed PROVENGE in the U.S. since 2010. Dendreon also is evaluating the use of PROVENGE in early-stage prostate cancer, with the hope of curing more men of the disease. Dendreon is headquartered in Seal Beach, Calif. For more information, please visit www.dendreon.com.

Contacts

Dendreon Pharmaceuticals LLC
Leslie Bryant, +1.562.505.9290
leslie.bryant@dendreon.com

Release Summary

New data about the PROVENGE (sipuleucel-T) mechanism of action correlates the magnitude of killer T cell activity with overall survival.

Contacts

Dendreon Pharmaceuticals LLC
Leslie Bryant, +1.562.505.9290
leslie.bryant@dendreon.com