Purpose: Adoptive cell transfer therapy (ACT) based on autologous tumor-infiltrating lymphocytes (TIL) has achieved impressive clinical results in several phase I and II trials performed outside of Europe. Although transient, the toxicities associated with high-dose (HD) bolus IL2 classically administered together with TILs are severe. To further scrutinize whether similar results can be achieved with lower doses of IL2, we have carried out a phase I/II trial of TIL transfer after classical lymphodepleting chemotherapy followed by an attenuated IL2 regimen.Experimental Design: Twenty-five patients with progressive treatment-refractory metastatic melanoma, good clinical performance, age < 70 years, and at least one resectable metastasis were eligible. TIL infusion was preceded by standard lymphodepleting chemotherapy and followed by attenuated doses of IL2 administered in an intravenous, continuous decrescendo regimen (ClinicalTrials.gov Identifier: NCT00937625).Results: Classical IL2-related toxicities were observed but patients were manageable in a general oncology ward without the need for intervention from the intensive care unit. RECIST 1.0 evaluation displayed three complete responses and seven partial responses (ORR 42%). Median overall survival was 21.8 months. Tumor regression was associated with a higher absolute number of infused tumor-reactive T cells. Moreover, induction and persistence of antimelanoma T-cell responses in the peripheral blood was strongly correlated to clinical response to treatment.Conclusions: TIL-ACT with a reduced IL2 decrescendo regimen results in long-lasting complete responses in patients with treatment-refractory melanoma. Larger randomized trials are needed to elucidate whether clinical efficacy is comparable with TIL-ACT followed by HD bolus IL2. Clin Cancer Res; 22(15); 3734–45. ©2016 AACR.

Background: Adoptive cell therapy may be based on isolation of tumor-specific T cells, e.g. autologous tumor infiltrating lymphocytes (TIL), in vitro activation and expansion and the reinfusion of these cells into patients upon chemotherapy induced lymphodepletion. Together with high-dose interleukin (IL)-2 this treatment has been given to patients with advanced malignant melanoma and impressive response rates but also significant IL-2 associated toxicity have been observed. Here we present data from a feasibility study at a Danish Translational Research Center using TIL adoptive transfer in combination with low-dose subcutaneous IL-2 injections. Methods: This is a pilot trial (ClinicalTrials.gov identifier: NCT00937625) including patients with metastatic melanoma, PS ≤1, age <70, measurable and progressive disease and no involvement of the central nervous system. Six patients were treated with lymphodepleting chemotherapy, TIL infusion, and 14 days of subcutaneous low-dose IL-2 injections, 2 MIU/day. Results: Low-dose IL-2 considerably decreased the treatment related toxicity with no grade 3–4 IL-2 related adverse events. Objective clinical responses were seen in 2 of 6 treated patients with ongoing complete responses (30+ and 10+ months), 2 patients had stable disease (4 and 5 months) and 2 patients progressed shortly after treatment. Tumor-reactivity of the infused cells and peripheral lymphocytes before and after therapy were analyzed. Absolute number of tumor specific T cells in the infusion product tended to correlate with clinical response and also, an induction of peripheral tumor reactive T cells was observed for 1 patient in complete remission. Conclusion: Complete and durable responses were induced after treatment with adoptive cell therapy in combination with low-dose IL-2 which significantly decreased toxicity of this therapy.

Immunotherapy can lead to long-term survival for some cancer patients, yet generalized success has been hampered by insufficient antigen presentation and exclusion of immunogenic cells from the tumor microenvironment. Here, we developed an approach to reprogram tumor cells in vivo by adenoviral delivery of the transcription factors PU.1, IRF8, and BATF3, which enabled them to present antigens as type 1 conventional dendritic cells. Reprogrammed tumor cells remodeled their tumor microenvironment, recruited, and expanded polyclonal cytotoxic T cells; induced tumor regressions; and established long-term systemic immunity in multiple mouse melanoma models. In human tumor spheroids and xenografts, reprogramming to immunogenic dendritic-like cells progressed independently of immunosuppression, which usually limits immunotherapy. Our study paves the way for human clinical trials of in vivo immune cell reprogramming for cancer immunotherapy.

Objective:Ovarian cancer (OC) is often diagnosed at an advanced stage with two thirds of patients experiencing recurrent disease with a poor prognosis. Adoptive cell therapy (ACT) with tumor-infiltrating lymphocytes (TIL) has shown curative potential in malignant melanoma, but has only been investigated scarcely in other cancers. In this pilot study, we tested TIL based ACT in patients with metastatic OC. Methods:Six patients with progressive platinum-resistant metastatic OC were treated with an infusion of TIL preceded by standard lymphodepleting chemotherapy and followed by decrescendo intravenous interleukin-2 (IL-2). Primarily, the feasibility and tolerability of the treatment was assessed. Secondarily, disease control rate was described and immune responses against tumor cells were monitored. Results:Treatment was well tolerated with manageable toxicities. Four patients had stable disease for three months and two patients for five months with five patients having a decrease in target lesions. Progression was primarily due to new lesions while target lesions in general remained stable or in regression. Antitumor reactivity was observed in TIL infusion products from five patients but no antitumor reactivity was detectable in peripheral blood lymphocytes collected after treatment. High numbers of infused TIL expressed exhaustion markers including LAG3 and PD-1, and immunostaining of tumor tissue demonstrated substantial MHCII and PD-L1 expression. Conclusions:ACT with TIL in combination with decrescendo IL-2 is feasible in patients with metastatic OC. Early indications of clinical activity were found. However, TIL ACT efficacy was incomplete with possible involvement of the inhibitory immune checkpoint pathways LAG3/MHCII and PD1/PD-L1.