Adoptive cell transfer for patients with metastatic melanoma: the potential and promise of cancer immunotherapy.

BACKGROUND

Current FDA-approved therapeutic options for patients with metastatic melanoma include dacarbazine, interleukin 2, ipilimumab, vemurafenib, dabrafenib, and trametinib, but long-term tumor regression using available agents remains out of reach for most patients. Adoptive cell transfer (ACT) with autologous tumor-infiltrating lymphocytes (TILs) has shown encouraging results in clinical trials, with evidence of durable ongoing complete responses in patients with advanced melanoma. Emerging techniques to engineer T-cell receptors (TCRs) or chimeric antigen receptors (CARs) using lymphocytes from peripheral blood may offer new tactics in ACT.

METHODS

We reviewed the literature to provide a synopsis on the development and clinical trial results of ACT, as well as the future outlook for using ACT in patients with metastatic melanoma.

RESULTS

ACT with TILs as part of a lymphodepleting regimen has been shown in clinical trials to cause objective clinical responses in approximately 40% to 72% of patients with metastatic melanoma, with up to 40% of those patients experiencing complete responses lasting up to 7 years ongoing. Pilot trials using TCR-engineered cells against melanoma-associated antigens MART-1 and gp100 and the cancer-testis antigen NY-ESO-1 have shown clinical responses in patients with melanoma. CAR cells directed against melanoma have been tested only in preclinical models; however, CAR cells targeting other histologies such as lymphoma have elicited antitumor responses in patients.

CONCLUSIONS

An example of state-of-the-art personalized medicine, ACT is a potentially curative therapy for patients with metastatic melanoma. Ongoing trials aiming to simplify the regimens may allow a broader range of patients to be treated and enable ACT to be offered by academic cancer centers.