Elios Announces Positive Top-Line Data Evaluating Personalized Therapeutic Cancer Vaccine

Elios Therapeutics announced positive top-line results from the Company's prospective, randomized, double-blind, placebo-controlled Phase IIb clinical trial evaluating its lead immuno-oncology candidate, the TLPLDC (tumor lysate, particle-loaded, dendritic cell) vaccine, in patients with Stage III and IV resected melanoma. The study met its primary endpoint by demonstrating a statistically significant reduction in the risk of disease recurrence at 24-months (disease-free survival; DFS) in the per treatment (PT) population.

The pre-specified primary efficacy analysis was performed on the intent-to-treat (ITT) and the PT populations as co-primary analyses given the high early recurrence rate often seen in patients with high-risk melanoma and the time needed for vaccines to activate the immune system. For all 144 patients enrolled in the study (ITT), including those who were never, or incompletely vaccinated, the recurrence rate was 66 percent in the placebo arm compared to 54 percent in the vaccine arm, representing an 18 percent clinically meaningful, though statistically non-significant, reduction in the relative risk of disease recurrence. However, the PT analysis of all patients who completed the primary vaccine series (six-months) of TLPLDC or placebo, demonstrated a 56 percent recurrence rate in the placebo arm versus 29 percent in the vaccine arm, representing a highly statistically significant 50 percent reduction in the relative risk of disease recurrence.

The independent Data Safety Monitoring Board (DSMB) responsible for evaluating the results of the study determined that there were no safety concerns with only one-third of patients experiencing a related adverse event (AE), the majority of which were grade 1 or 2. Furthermore, an initial assessment of 36-month follow-up data on all patients indicates that the TLPLDC vaccine benefit is not only durable, but continues to show benefit beyond 24-months. As a result, the DSMB recommended that the study continue as designed to the 36-month landmark endpoints of DFS and overall survival, anticipated in June 2020.

"As a treating physician, substantially reducing the risk of cancer from returning is a high priority for me and my patients. To be able to create a customized vaccine using a patient's own tumor that can immunize them against their cancer is an exciting possibility," said Mark B. Faries, M.D., co-director of the Melanoma Program and head of Surgical Oncology at The Angeles Clinic and Research Institute. "These data show a strong signal for clinical benefit with the risk of recurrence cut in half among patients who received the initial course of vaccine. They also confirm the remarkable safety of the vaccine, adding to its appeal as a potential new treatment option for patients at high risk for recurrence."

Melanoma is less common than some other types of skin cancer, but it is more likely to grow and spread. When diagnosed and treated at an early stage, it has a high cure rate, however patients with later stages of the disease carry a high risk for melanoma recurrence because some melanoma cells can remain in the body, even after surgery. In the U.S, the incidence of melanoma has increased over the past decades, with 91,270 estimated new cases and 9,320 related deaths in 2018.1 

This Phase IIb study is a prospective, randomized, double-blind, placebo-controlled trial designed to evaluate the safety and efficacy of the TLPLDC (tumor lysate, particle-loaded, dendritic cell) vaccine in patients with resected Stage III and IV melanoma. The primary endpoint of the trial is two-year disease-free survival (DFS).

In the study, 144 participants were randomized to receive either the vaccine or placebo to prevent recurrence. TLPLDC or placebo vaccines were initiated within three months of completion of standard of care (SoC) therapies and were given at 0, 1, 2, 6, 12, and 18 months. Study participants were followed for recurrence per SoC. The primary efficacy analysis was performed on the intent-to-treat (ITT) and the per treatment (PT) populations as co-primary analyses given the high early recurrence rate often seen in patients with advanced melanoma. Secondary endpoints include 36-month DFS and overall survival (OS) which will be compared between the vaccinated and control groups.

The TLPLDC (tumor lysate, particle-loaded, dendritic cell) vaccine is a unique type of immunotherapy, both in how it is made and how it is delivered. The vaccine is personalized, meaning it is made from a patient's tumor and blood. Every patient's tumor has a unique antigenic profile unlike any other, and dendritic cells found in the blood are the most potent antigen presenting cells in the body. Once TLPLDC is administered, it delivers the patient's complete repertoire of tumor antigens to the immune system, creating a dual innate and adaptive immune response, activating fighter T cells, and triggering the immune system to recognize, and seek out and destroy any cells containing the antigens and specific mutations from their tumor.

The TLPLDC vaccine is currently being studied as a monotherapy and in combination with standard-of-care checkpoint inhibitor therapies in a Phase IIb clinical trial for the treatment of late-stage melanoma at leading academic cancer centers in the United States.

-----------------------------------------------------------------------
Editor's Note:

If you have any suggestion to the content, 

please email: Julia.Zhang@ubmsinoexpo.com