Patients with relapsed or refractory (r/r) acute myeloid leukemia (AML) have very poor long-term outcomes. Allogeneic stem cell transplantation (allo-SCT) can potentially cure some of these patients who are able to achieve a second or greater remission with salvage chemotherapy. Unfortunately, several barriers exist to transplantation and not all patients with r/r AML are able to proceed to allo-SCT. Therefore, novel therapies to decrease the risk of relapse in these patients are urgently needed. Wilms tumor 1 (WT1) protein has emerged as an encouraging vaccine target in AML due to its overexpression in leukemic blast cells and near absence in normal hematopoietic cells. Maintenance therapy with galinpepimut-S, a multivalent heteroclitic WT1 peptide vaccine, holds promise in early phase trials, in patients with AML by inducing a strong innate immune response against the WT1 antigen, leading to the design of this international, open-label, randomized clinical trial, named REGAL. Clinical trial registration: https://clinicaltrials.gov/study/NCT04229979. The clinical trial identifier is NCT04229979.
Keywords: Acute myeloid leukemia; complete remission; galinpepimut-S; maintenance; randomized trial.
Maintenance therapy in acute myeloid leukemiaThe REGAL trial is testing a new drug called galinpepimut-S (GPS), as a maintenance therapy, in patients with a blood cancer called acute myeloid leukemia (AML) who are in remission. Patients in remission do not have any evidence of leukemia, and the goal of the maintenance therapy would be to prevent the leukemia from coming back. The leukemia always has a chance of coming back, even if patients are in remission. Patients whose leukemia comes back have very poor outcomes as it highlights the aggressive nature of the leukemia. If these patients can get into remission again, they need to proceed to a bone marrow transplant from a healthy donor to have a chance at the best long-term outcomes. Unfortunately, many patients are not able to proceed to transplant due to various reasons. If a patient is not able to proceed to transplant, the outcomes are very poor. Currently, there is no approved therapy for such patients with AML. We are investigating a new vaccine to try to help these patients. This vaccine is called GPS. It has already been investigated as maintenance therapy in patients with AML in early phase trials with promising results. Now GPS is being investigated in a larger trial called the REGAL trial. If the REGAL trial results are positive, it will provide a new treatment option for these patients.