Lenolidamide and IL-15 enhance natural killer cell-mediated immunity and augments the anti-tumor effect of an anti-CD30/CD16A bispecific antibody against Hodgkin’s lymphoma B-cells

Abstract

Abstract Hodgkin’s lymphoma (HL) is characterized by malignant CD30+ Reed-Sternberg (HRS) B-cells surrounded by an ineffective infiltrate of inflammatory immune cells. T-helper and T-regulatory cells presumably provide survival signals for HRS cells; rescuing them from immune-surveillance by CD8+ cytotoxic T lymphocytes and natural killer (NK) cells, which are also functionally anergic. Clinically, ≈10–30% of HL patients resulted in relapse after front line therapy; highlighting the need for development of new treatments. We investigated a novel bispecific CD16axCD30 antibody, AFM13 (Affimed Therapeutics, AG), which engages NK cells and recruits them towards CD30+ tumor cells. Safety of single-agent AFM13 has been demonstrated in a phase I clinical study, however, disease remission was observed in only 23% of patients. We hypothesized that combining AFM13 with another agent whose safety profile is already been established in HL and also activates NK cells (lenalidomide) could potentially increase anti-tumor efficacy of AFM13. We observed increased expression of CD107a, CD69, CD25 and IFNγ (activation markers) in NK cells isolated from HL patients (HL-NK), that were stimulated ex vivo with IL- 15 + lenalidomide. Pre-treatment with IL-2/IL-15 antibody has been shown to activate and restore T/NK cell cytolytic function. In line with this, IL-15+lenalidomide-stimulated HL-NK cells showed functional restoration by inducing specific lysis of human CD30+ lymphoma cells (30.55±1.49%) in a co-culture assay. While, AFM13 is being investigated in combination with anti-PD1 antibody therapy (NCT02665650), our preclinical data provides the rationale for an AFM13 + Len combination regimen for HL and potentially other CD30+ malignancies.