Tumour-infiltrating lymphocyte therapy improved progression-free survival compared to ipilimumab in patients with advanced melanoma
Tumour-infiltrating lymphocyte therapy (TILT) provided superior progression-free survival to immune checkpoint inhibitor therapy with ipilimumab in a phase 3 trial of patients with advanced melanoma according to the findings of a study presented at the European Society for medical Oncology (ESMO) Congress by Dutch researchers.
Tumour-infiltrating lymphocyte therapy is a type of adoptive cellular therapy in which infiltrated lymphocytes are removed from a patient’s tumour and grown in large numbers in a laboratory. These cells are then infused back into the patient to help the immune system kill the cancer cells. In fact, studies have already suggested that TILT can mediate a durable complete responses in patients with metastatic melanoma with similar efficacy irrespective of prior treatment. In a phase 2 open-label trial, Lifileucel, which is an autologous, centrally manufactured tumour-infiltrating lymphocyte product, demonstrated durable responses, addressing a major unmet need in patients with metastatic melanoma with limited treatment options after approved therapy. However, to date, there have been no phase 3 trials examining the value of tumour-infiltrating lymphocyte therapy in patients with advanced melanoma.
The current study was a multicentre, open-label phase 3 trial of patients with unresectable stage IIIC-IV melanoma, aged between 18 and 75 and who were randomised 1:1 to TILT or ipilimumab (3mg/kg q3wks, max 4 doses). Individuals were stratified for BRAFV600 mutation status, treatment line and centre. Those receiving TILT underwent resection of a melanoma lesion (2-3cm) for the ex vivo outgrowth and expansion of tumour resident T cells. The researchers set the primary endpoint as progression-free survival (PFS) per RECIST 1.1 whereas secondary endpoints were (overall and complete) response rate, overall survival (OS) and safety.
Tumour-infiltrating lymphocyte therapy and progression-free survival
A total of 168 patients, the majority (86%) of whom were refractory to anti-programmed cell death-1 ligand treatment, received TILT (84) or ipilimumab.
After a median follow-up of 33 months, the median PFS was 7.2 months for TILT (95% CI 4.2 – 13.1) compared to 3.1 months (95% CI 3.0 – 4.3) for ipilimumab, giving a hazard ratio, HR of 0.50 (95%CI 0.35 – 0.72, p < 0.001).
The overall response rate was 49% for TILT but only 21% for ipilimumab and 20% of those receiving TILT achieved a complete response compared to 7% for ipilimumab. The median OS for TILT was 25.8 months and 18.9 months for ipilimumab. Moreover, grade ≥3 treatment-related adverse events occurred in all TILT patients but only and 57% of those assigned to ipilimumab.
The authors concluded that TILT therapy significantly improved PFS compared to ipilimumab, adding that since the vast majority of those included in the trial were anti-PD-1 refractory, TILT was a potential new treatment option in this patient population.