Personalized Cancer Vaccine Yields Promising Results for Patients With High-Risk Melanoma

A personalized therapeutic cancer vaccine candidate is offering promise in patients with high-risk melanoma, according to positive topline study results. Elios Therapeutics announced results of its prospective, randomized phase 2b clinical trial testing the vaccine in patients with stage III and IV resected melanoma.

The TLPLDC (tumor lysate, particle-loaded, dendritic cell) vaccine met the study’s primary end point of demonstrating a statistically significant reduction in risk of recurrence at 24 months. This is the first phase 2b study to yield positive results for a personalized vaccine in patients with high-risk melanoma.

“From the moment a person is diagnosed to long after their final treatment, the fear of disease recurrence remains constant for many patients,” Kyleigh LiPira, MBA, chief executive officer of the Melanoma Research Foundation, said in a statement. “The possibility of having a personalized immunotherapy that can prevent melanoma from coming back after surgery makes this a welcome advance for patients and their families.”

By using a patient’s own tumor and dendritic cells in the blood, the vaccine is able to deliver antigens specific to the tumor’s antigenic profile to the immune system, which creates a natural and adaptive immune response, thus activating fighter T cells and triggering the immune system to recognize and destroy any cancer cells.

To date, there is just one FDA-approved vaccine for the treatment of cancer. However, researchers continue to work toward a goal of vaccines playing an integral role in cancer treatment. Over the last 6 months, several trials have made headlines for their preliminary but promising results, and Elios Therapeutics' study is the latest to do so.

Among the 144 patients enrolled in the study, which included patients who were never or incompletely vaccinated, there was a 54% recurrence rate among patients who received the vaccine compared with a 66% recurrence rate among patients receiving placebo. The 18% reduction in risk seen with the vaccine was clinically meaningful, although not statistically significant. However, when only including patients who completed the 6-month vaccine series with either TLPLDC or placebo, there was a 29% recurrence rate among patients receiving the vaccine compared with a 56% recurrence among patients receiving placebo.

“As a treating physician, substantially reducing the risk of cancer from returning is a high priority for me and my patients,” said Mark B. Faries, MD, codirector of the Melanoma Program and head of Surgical Oncology at The Angeles Clinic and Research Institute, in a statement. “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. 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.”

Patients started receiving the vaccine or placebo within 3 months of completing standard of care therapies and the vaccines were administered at 0, 1, 2, 6, 12, and 18 months.

Initial review of 36 months’ worth of data indicated that the observed clinical benefits associated with the vaccine are durable and continue to show benefit beyond 24 months. Study findings also revealed no safety concerns, with one-third of patients experiencing a treatment-related adverse event. The majority of these events were grade 1 or 2.