A phase II randomised controlled trial of adjuvant tumour-infiltrating lymphocytes for pretreatment Epstein-Barr virus DNA-selected high-risk nasopharyngeal carcinoma patients.

Purpose: The safety and objective clinical responses were observed in the phase I study using adjuvant autologous tumour-infiltrating lymphocytes (TILs) following concurrent chemoradiotherapy (CCRT) in nasopharyngeal carcinoma (NPC) patients.

Methods And Materials: One hundred fifty-six patients with stage III-IVb and pretreatment Epstein-Barr virus DNA levels of ≥4000 copies/ml were randomly assigned to receive CCRT combined with TIL infusion (n = 78) or CCRT alone (n = 78). All patients received CCRT and patients assigned to the TIL group received TIL infusion within 1 week after CCRT. The primary endpoint was investigator-assessed progression-free survival (PFS) at 3 years.

Results: After a median follow-up of 62.3 months, no significant difference was observed in the 3-year PFS rate between the CCRT plus TIL infusion group and CCRT alone group (75.6% versus 74.4%, hazard ratios, 1.08; 95% confidence intervals, 0.62-1.89). TIL infusion was safe without grade 3 or 4 adverse events and all the high-grade adverse effects were associated with myelosuppression caused by CCRT. Exploratory analysis showed that a potential survival benefit was observed with TILs in patients with lower levels of circulating CD8+TIM3+ cells, serum IL-8 or PD-L1. The infused TIL products in patients with favourable outcomes were associated with increased transcription of interferon-γ and a series of inflammatory related genes and a lower exhausted score.

Conclusion: The primary objective of prolonging PFS with CCRT plus TILs in high-risk NPC patients was not met. These findings may provide evidence for the design of future trials investigating the combination of TILs plus immune checkpoint inhibitors based on CCRT in high-risk NPC patients.

Trial Registration Number: NCT02421640.