Randomized phase II trial of lymphodepletion plus adoptive cell transfer of tumor-infiltrating lymphocytes, with or without dendritic cell vaccination, in patients with metastatic melanoma

Abstract

Background: The adoptive transfer of tumor-infiltrating lymphocytes (TIL) has demonstrated robust efficacy in metastatic melanoma patients. Tumor antigen-loaded dendritic cells (DCs) are believed to optimally activate antigen-specific T lymphocytes. We hypothesized that the combined transfer of TIL, containing a melanoma antigen recognized by T cells 1 (MART-1) specific population, with MART-1-pulsed DC will result in enhanced proliferation and prolonged survival of transferred MART-1 specific T cells in vivo ultimately leading to improved clinical responses.

Design: We tested the combination of TIL and DC in a phase II clinical trial of patients with advanced stage IV melanoma. HLA-A0201 patients whose early TIL cultures demonstrated reactivity to MART-1 peptide were randomly assigned to receive TIL alone or TIL +DC pulsed with MART-1 peptide. The primary endpoint was to evaluate the persistence of MART-1 TIL in the two arms. Secondary endpoints were to evaluate clinical response and survival.

Results: Ten patients were given TIL alone while eight patients received TIL+DC vaccine. Infused MART-1 reactive CD8⁺ TIL were tracked in the blood over time by flow cytometry and results show good persistence in both arms, with no difference in the persistence of MART-1 between the two arms. The objective response rate was 30% (3/10) in the TIL arm and 50% (4/8) in the TIL+DC arm. All treatments were well tolerated.

Conclusions: The combination of TIL +DC showed no difference in the persistence of MART-1 TIL compared with TIL therapy alone. Although more patients showed a clinical response to TIL+DC therapy, this study was not powered to resolve differences between groups.

Trial registration number: NCT00338377.

Keywords: adaptive immunity; dendritic cells; lymphocytes; melanoma; tumor-infiltrating; vaccination.

Figure 1

The infusion of a larger proportion of CD8⁺ TIL tends to associate with longer survival. (A) Total number of TIL infused by arm (left panel) or responsecircles represent patients treated with TIL alone while squares denote patients who received TIL +DC. Mean and SD are shown. Statistics were calculated with double sided Mann-Whitney U test. (B) %CD8⁺ TIL infused by arm (left panel) or response (right panel). Circles represent patients who responded (CR or PR) while squares denote patients who did not respond (SD or PD). Mean and SD are shown. Statistics were calculated with double sided Mann-Whitney U test. (C) %CD8⁺ TIL infused and PFS D) %CD8⁺ TIL infused and OS. (E) Kaplan-Meier plot of OS stratified by %CD8⁺ TIL infused (≥50% or <50%). CR, complete response; DC, dendritic cell; ns, not significant; OS, overall survival; PFS, progression-free survival; PD, progressive disease; PR, partial response; SD, stable disease; TIL, tumor-infiltrating lymphocytes.

Figure 2

MART-1 reactivity of TIL #302 infusion product. (A) Flow cytometry evaluation of MART-1 reactivity in infusion product from TIL #302. Gating strategy demonstrates the gating of viable (7AAD negative) lymphocytic population. The cells were stained for CD8 and either no tetramer (left plot), gp100 dextramer (middle plot) or MART-1 dextramer (right plot). (B) Nanostring analysis of TCR clonotypes. (C) Sequencing data of the CDR3 region of the alpha chain of the TCR. (D) Sequencing data of the CDR3 region of the beta chain of the TCR. (E) Alignment of the CDR3 sequence of the alpha and beta chains of the TCR with published sequences from CDR3 regions of MART-1 recognizing TCRs. MART-1, melanoma antigen recognized by T cells 1; TIL, tumor-infiltrating lymphocytes.

Figure 3

Persistence of MART-1 reactive CD8⁺ TIL after infusion. (A) %MART-1 reactive CD8⁺ TIL infused by arm (left panel) and response (right panel). Circles represent patients treated with TIL alone while triangles denote patients who received TIL+DC. Statistics were calculated with double-sided Mann-Whitney U test. (B) %MART-1 reactive CD8⁺ TIL, as a proportion of total CD8⁺ T cells, circulating in the blood at 1 month post TIL infusion, by arm. Circles represent patients treated with TIL alone while triangles denote patients who received TIL+DC. Statistics were calculated with double sided Mann-Whitney U test. (C) Longitudinal tracking of MART-1 reactive CD8⁺ T cells in the blood of patients treated in the TIL arm. Dotted lines indicate Responder patients. Values less than 0.001% (or undetected) were represented as 0.001% to allow visualization on a logarithmic axis (D) longitudinal tracking of MART-1 reactive CD8⁺ T cells in the blood of patients treated in the TIL+DC arm by flow cytometry. Dotted lines indicate Responder patients. values less than 0.001% (or undetected) were represented as 0.001% to allow visualization on a logarithmic axis. DC, dendritic cell; ns, not significant; MART-1, melanoma antigen recognized by T cells 1; TIL, tumor-infiltrating lymphocytes.

Figure 4

Clinical response to TIL with or without DC co-vaccination. (A) Waterfall plot (B) spider plot depicting the tumor burden of every patient at every time point collected. Patients in the TIL arm are denoted by a black curve while patients in the TIL +DC arm are denoted by a blue curve. (C) Kaplan-Meier plot showing pfs by treatment arm. (red curve is for TIL alone and blue curve is for TIL+DC patients). The median PFS duration was 0.26 years in the TIL arm and 0.49 years in the TIL +DC arm. The 2-year PFS rate was 0% (95% CI 1.6% to 64%) in the TIL arm and 13% in the TIL +DC arm (95% CI 13% to 78%). (D) Kaplan-Meier plot of os by treatment arm. (Red curve is for TIL alone and blue curve is for TIL +DC patients). The median OS duration was 4.1 years in the TIL arm and 2.0 years in the TIL+DC arm. at 2 years, the OS rate was 58% (95% CI 34% to 100%) in the TIL arm and 50% in the TIL +DC arm (95% CI 25% to 100%). DC, dendritic cell; OS, overall survival; PFS, progression-free survival; TIL, tumor-infiltrating lymphocytes.

Figure 5

Long-term systemic tumor control following local radiation of the brain in patients who had received TIL. Systemic tumor burden decreases over time in three patients who received local intracranial radiation of the brain within a month of being treated with TIL therapy (Patients #228, 232 and 312). TIL, tumor-infiltrating lymphocytes. Abbreviations: FDG, Fluorodeoxyglucose. NED, No evidence of disease.