Study Evaluates Lymphodepletion Intensity Before Adoptive Cell Transfer in Melanoma

The addition and intensification of total body irradiation to the lymphodepleting chemotherapy regimen in patients undergoing adoptive cell transfer of tumor-infiltrating lymphocytes for metastatic melanoma did not improve outcomes, a study published in the Journal of Clinical Oncology has shown.¹

Adoptive cell transfer, the infusion of large numbers of activated autologous lymphocytes, can induce objective tumor regression in a majority of patients with metastatic melanoma.

Because previous research has demonstrated that the addition and intensification of total body irradiation to the preparative chemotherapy regimen improved objective complete and partial response rates, investigators sought to assess the importance of adding total body irradiation in a randomized trial.

For the study, researchers enrolled 101 patients with metastatic melanoma, including 76 with M1c disease. Participants were randomly assigned to receive nonmyeloablative chemotherapy with or without 1200 cGy total body irradiation prior to the transfer of tumor-infiltrating lymphocytes.

Results showed that 24% of patients in both treatment arms achieved a complete response. Median overall survival was 38.2 months in patients who received total body irradiation compared with 36.6 months in those who did not (HR, 1.11; 95% CI, 0.65-1.91; P = .71).

In regard to safety, 13 of 48 evaluable patients in the total body irradiation arm reported thrombotic microangiopathy, an adverse event unique to that arm.

The study further demonstrated that only 1 of the 24 patients who achieve a complete response developed recurrent disease after a median potential follow-up of 40.9 months.                  

Reference

1. Goff SL, Dudley ME, Citrin DE, et al. Randomized, prospective evaluation comparing intensity of lymphodepletion before adoptive transfer of tumor-infiltrating lymphocytes for patients with metastatic melanoma [published online ahead of print May 23, 2016]. J Clin Oncol. doi: 10.1200/JCO.2016.66.7220.