A Phase II Study of Pembrolizumab as Post-Remission Treatment of Patients ≥ 60 With AML

Patients \>60 years old with AML often have a dismal prognosis. Even though many of these patients are able to obtain a Complete Response to treatment, relapse occurs in the vast majority of patients. Transplants may reduce relapse rates in this population, but is only feasible in a minority of patients. AML's immunosuppressive microenvironment in general and PD-1/PD-L1 upregulation in particular appears to increase the risk of relapse. Importantly, PD-1 and its ligands are particularly increased after therapy compared to initial diagnosis. As such, PD-1 inhibition with pembrolizumab offers to limit leukemic cell immune escape, thereby allowing the patient's immune system to eradicate the submicroscopic residual disease and reducing relapse rates. Treatment for this study is 200 mg Q3W as an appropriate dose for the switch to fixed dosing is based on simulations performed using the population PK model of Pembrolizumab showing that the fixed dose of 200 mg every 3 weeks will provide exposures that 1) are optimally consistent with those obtained with the 2 mg/kg dose every 3 weeks, 2) will maintain individual patient exposures in the exposure range established in melanoma as associated with maximal efficacy response and 3) will maintain individual patients exposure in the exposure range established in melanoma that are well tolerated and safe.