Results from a clinical trial have revealed nearly one third (29.2 per cent) of patients with advanced melanoma saw their tumours disappear completely on scans after receiving lifileucel TIL therapy alongside an immune checkpoint inhibitor, pembrolizumab, as a first-line treatment. 

In addition, approximately two thirds (62.5 per cent) of patients in the same group saw their tumours shrink significantly, with many experiencing substantial and long-lasting responses to the combined treatment.

These findings from the IOV-COM-202 clinical trial, an international, multicentre Phase II trial conducted at The Royal Marsden NHS Foundation Trust, were presented at the 2026 European Society for Medical Oncology Congress by Dr Andrew Furness, Consultant Medical Oncologist and Solid Tumour Cellular Therapy Lead at The Royal Marsden NHS Foundation Trust and Leader of the Cellular Therapy and Translational Immunology Group at The Institute of Cancer Research, London.

The findings suggest that introducing lifileucel earlier in the treatment pathway may improve outcomes for patients. In 2024, lifileucel became the first cellular therapy approved by the U.S. Food and Drug Administration (FDA) for solid tumours after the C-144-01 clinical trial demonstrated a response rate of 31.4 per cent in patients whose cancer had progressed following previous treatments.1 This study aimed to understand whether the therapy could deliver greater benefit when used earlier in the course of the disease. 

Lifileucel and pembrolizumab are two distinct forms of cancer immunotherapy. Lifileucel is a tumour-infiltrating lymphocyte (TIL) therapy, which harnesses the power of a patient’s immune system by extracting immune cells from a patient’s tumour, multiplying them in a laboratory, and returning them to the bloodstream, allowing them to more effectively recognise and attack cancer cells.

Pembrolizumab is an immune checkpoint inhibitor, a type of drug that blocks proteins which normally restrain the immune system, allowing a patient’s T cells to better detect and attack cancer cells. 

Pembrolizumab is a proven first-line treatment for many patients with advanced melanoma. However, a significant fraction of patients do not experience long-lasting benefit. Lifileucel has been shown to offer a second chance at long-lasting cancer control when standard immunotherapies, including pembrolizumab, are no longer effective. The IOV-COM-202 trial sought to determine the potential benefit of combining both therapies as a first-line treatment.

The trial selected 27 patients with advanced melanoma and treated them with a combination of pembrolizumab and lifileucel. Patients first received chemotherapy to prepare the body for treatment, before receiving the cell infusion and a short course of interleukin-2, a drug that boosts immune cell activity and is given after TIL therapy to help the infused cells grow and attack the cancer. Of the 27 patients treated, 24 were included in the trial’s main analysis.3

After a median follow-up period of 26.9 months, researchers found that 15 of the 24 patients (62.5 per cent) experienced significant tumour shrinkage, with approximately one third (29.2 per cent) of patients seeing their tumours disappear completely on scans.

The median duration of response had not yet been reached more than two years after the trial began, meaning that many patients who responded to treatment were still benefiting from it at the time of analysis. 

Among the 15 patients whose cancer responded to treatment, 13 maintained their response for at least 12 months, while 10 remained in complete or partial response at their most recent assessment. 

Median progression-free survival, which is the length of time before a patient's cancer returned or progressed, was 19.8 months. Median overall survival, the length of time within the trial that a patient remained alive, had not yet been reached after 50.9 months of follow-up.

Patients experienced no additional side effects beyond those associated with the individual treatments.

Researchers are now evaluating this approach in TILVANCE-301, an international Phase III trial comparing lifileucel plus pembrolizumab with pembrolizumab alone in patients with advanced melanoma, for which Dr Andrew Furness is the UK National Chief Investigator.

Dr Andrew Furness, Consultant Medical Oncologist and Solid Tumour Cellular Therapy Lead at The Royal Marsden NHS Foundation Trust and Honorary Faculty at The Institute of Cancer Research (ICR), whose role is part-funded by The Royal Marsden Cancer Charity, said: 

“Immune checkpoint inhibitors like pembrolizumab have transformed outcomes for patients with advanced melanoma, with around half of patients achieving long-term cancer control. However, for those that do not derive long-term benefit, novel therapeutic options are urgently required.

"Our findings suggest that adding TIL therapy to first-line pembrolizumab can produce deep and durable responses. Larger studies will now help us understand which patients are most likely to benefit from this combination and how it can best be used alongside existing immunotherapies."

After being diagnosed with melanoma in 2024, Paul Jenner, 59, a former ballet dancer and landscape construction company owner from London, now retired, was referred to The Royal Marsden after tests showed his cancer had spread beyond the original site to nearby lymph nodes. Paul joined the IOV-COM-202 trial and received TIL therapy and pembrolizumab in August 2024. His cancer is currently in remission. He said: 

“It's amazing, really, that your own cells can be used in this way and used to heal you. Before I had the treatment, there was spread to my lung, there was a growth on my back and there were a couple of other areas doctors were keeping an eye on. These all disappeared after the TIL therapy and pembrolizumab.

“The Royal Marsden is an incredible place and there are such lovely people working there, from everyone on the wards to the research staff who talked me through the trial. You can't help but feel grateful to have the chance to have something like TIL therapy. I don't know where I'd be without it.”

The IOV-COM-202 study is funded by Iovance Biotherapeutics, Inc. Solid tumour cellular therapy research at The Royal Marsden is funded by supporters of The Royal Marsden Cancer Charity including our charity partner Nationwide, and The National Institute for Health and Care Research (NIHR) Biomedical Research Centre at The Royal Marsden and the ICR.

Source: The Royal Marsden NHS Foundation Trust