Data Demonstrates Extension of Survival of Metastatic Melanoma Patients Treated with Proleukin Followed by Immune Checkpoint Blockade of the Programmed Death (PD-1/PD-L1) Pathway
Chicago, Ill., May 28, 2015 –– Prometheus Laboratories, Inc. announced today the presentation of data from patients enrolled in the PROCLAIMSM national patient registry, demonstrating the safety and efficacy of Proleukin® (aldesleukin for injection) when treated in sequence with checkpoint therapy in patients with metastatic melanoma (mM). In a poster session to be presented on May 30th at the 2015 annual meeting of the American Society of Clinical Oncology (ASCO) in Chicago, investigators describe favorable safety results for Proleukin when administered after therapy directed against the cytotoxic T-lymphocyte antigen 4 (CTLA-4) or programmed cell death receptor-1 (PD-1) pathways.
“Early results from the PROCLAIM database suggest that high-dose interleukin-2 (HD IL-2) is a safe treatment option for patients with metastatic melanoma who were previously treated with immune checkpoint blockade,” said Elizabeth I. Buchbinder, MD, author of the study and instructor in Medical Oncology at the Dana-Farber Cancer Institute in Boston, Mass. “Additionally, the overall response rates and survival benefit of high-dose IL-2 do not appear to be significantly affected by prior checkpoint inhibitor therapy, and are consistent with previously reported data showing durable, long-term responses.”
The national PROCLAIMSM (PROLEUKIN® Observational Study to Evaluate the Treatment Patterns and Clinical Response in Malignancy) patient registry represents the largest active collection of IL-2 treated patients and provides data on the current implementation on the use of Proleukin in patients with mM and metastatic renal cell carcinoma (mRCC). The registry encompasses over 40 participating sites, which include immunotherapy treatment centers and community oncology practices, and features a retrospective cohort of patients treated between 2007 and 2012, as well as an on-going prospective cohort of over 600 patients.
In an analysis of early data from prospectively enrolled patients (abstract #3053), Dr. Buchbinder and colleagues reviewed safety and efficacy data from patients with mM and mRCC who received the CTLA-4 inhibitor ipilimumab (ipi, n = 47) or an anti-PD-1 (aPD-1, n = 4) before receiving Proleukin therapy, and compared these data to those from patients who received Proleukin only (n = 112). The most commonly reported toxicities were hypotension, thrombocytopenia, and diarrhea in the Proleukin-alone and ipilimumab patient groups, while hypotension, nausea/vomiting, and pulmonary edema were most common in the aPD-1 patient group. In patients evaluable for adverse events (AEs), 6.4% of the ipi prior patients, 1.9% of Proleukin only patients and none of the aPD-1 prior patients developed immune-related AEs. Median overall survival (mOS) was 16 months in the ipi group, 14.5 months in the aPD-1 group, and 14 months in the Proleukin only group. The overall response rate (ORR) for patients treated with Proleukin after ipi or anti-PD-1 was 17.7%, while the ORR for patients treated with Proleukin only was 22.9%.
In addition, analysis of data in which follow-on therapy with checkpoint blockade of the CTLA-4 and PD-1/PD-L1 pathways show a potential therapy-enhancing role after initial treatment with Proleukin. This analysis covers 236 prospectively entered patients from 26 sites with mM. Patients were stratified into 3 groups; Proleukin only (n=123), Proleukin followed by ipilimumab (Post-ipi, n=78), and Proleukin followed by PD-1/PD-L1 inhibitors (Post-αPD-1, n=35). The median overall survival (mOS) for the entire group of patients was 18.4 months with a median follow-up of 21.7 months. Patients in the Proleukin only, Post-ipi, and Post-αPD-1 groups achieved a mOS of 14, 15.7, and 28.7 months, respectively. With a median follow-up of 21.7 months, the estimated 12-month survival rates were 57%, 64%, and 97%, respectively. Treatment with anti-PD-1/PD-L1 containing regimens after initial therapy with HD IL-2 was associated with significantly prolonged survival compared with Proleukin alone and Post-ipi groups. There were 10/78 (13%) and 3/35 (8.5%) treatment-related incidences of autoimmune events in the groups who received ipilimumab or anti-PD-1, respectively. No treatment related deaths were reported.
“This is the first clinical report of HD IL-2 use followed by blockade of the PD-1/PD-L1 pathway,” noted lead investigator Michael K. Wong, MD, PhD, professor of Medicine and Head of the Solid Tumor Section at the University of Southern California Norris Comprehensive Cancer Center. “Although the small sample size in the anti-PD-1/PD-L1 group limits our ability to make a definitive conclusion about optimal sequencing of immunotherapies, checkpoint inhibitor therapy after HD IL-2 appears to be well-tolerated, does not impact therapeutic activity, and provides a path forward for trials designed to enhance durable, unmaintained IL-2 responses. We look forward to exploring these possibilities in future trials.”
Proleukin® (aldesleukin) for injection is a recombinant human interleukin-2 treatment for adults with metastatic melanoma and metastatic kidney cancer. Proleukin therapy is a form of immunotherapy that enhances the body’s natural immune system to help fight these types of cancer. Proleukin has been used for 17 years in the treatment of metastatic melanoma and for 20 years in the treatment of metastatic kidney cancer (renal cell carcinoma). For complete prescribing information, please visit http://www.proleukin.com/.
Important Safety Information
Therapy with Proleukin® (aldesleukin) for injection should be restricted to patients with normal cardiac and pulmonary functions as defined by thallium stress testing and formal pulmonary function testing. Extreme caution should be used in patients with a normal thallium stress test and a normal pulmonary function test who have a history of cardiac or pulmonary disease.
Proleukin should be administered in a hospital setting under the supervision of a qualified physician experienced in the use of anticancer agents. An intensive care facility and specialists skilled in cardiopulmonary or intensive care medicine must be available.
Proleukin administration has been associated with capillary leak syndrome (CLS), which is characterized by a loss of vascular tone and extravasation of plasma proteins and fluid into the extravascular space. CLS results in hypotension and reduced organ perfusion, which may be severe and can result in death. CLS may be associated with cardiac arrhythmias (supraventricular and ventricular), angina, myocardial infarction, respiratory insufficiency requiring intubation, gastrointestinal bleeding or infarction, renal insufficiency, edema, and mental status changes.
Proleukin treatment is associated with impaired neutrophil function (reduced chemotaxis) and with an increased risk of disseminated infection, including sepsis and bacterial endocarditis. Consequently, preexisting bacterial infections should be adequately treated prior to initiation of Proleukin therapy. Patients with indwelling central lines are particularly at risk for infection with gram-positive microorganisms. Antibiotic prophylaxis with oxacillin, nafcillin, ciprofloxacin, or vancomycin has been associated with a reduced incidence of staphylococcal infections.
Proleukin administration should be withheld in patients developing moderate to severe lethargy or somnolence; continued administration may result in coma.
Interleukin-2 (IL-2) is a protein that occurs naturally in the body and plays an important role in activating the immune system. The immune system protects the body from foreign substances, cells, and tissues by responding to and resisting diseases. Proleukin is a genetically engineered or recombinant version of IL-2. Proleukin possesses the same biological properties as naturally occurring IL-2 and helps activate the immune system to recognize and eliminate certain kinds of cancer cells.
Prometheus Laboratories Inc. is committed to improving lives through the development and commercialization of novel pharmaceutical and diagnostic products that enable physicians to provide greater individualized patient care. Prometheus is a leader in applying the principles of personalized medicine to the diagnosis and treatment of gastrointestinal diseases and is applying these principles to oncology. Its strategy includes the marketing and delivery of pharmaceutical products complemented by proprietary diagnostic testing services. By integrating therapeutics and diagnostics, Prometheus believes it can provide physicians with more targeted solutions to optimize care for their patients. Prometheus became part of Nestlé Health Science in July 2011. Prometheus’ corporate offices are located in San Diego, California. For more information about Prometheus, please visit www.prometheuslabs.com.
Proleukin is a registered trademark of Novartis Vaccines & Diagnostics, Inc.