New developments in the treatment of multiple myeloma - clinical utility of daratumumab

Myeloma patients' experiences of haematopoietic stem cell transplant: A qualitative thematic synthesis

PURPOSE

The aim of this study was to synthesise all qualitative evidence on the experiences of myeloma patients undergoing haematopoietic stem cell transplant (HSCT).

METHOD

A systematic search strategy was developed and a rigorous search of the literature was undertaken searching six databases (CINAHL, Embase, Medline, Psych Info, Ethos and Proquest). The software for systematic reviews www.covidence.org was used to blind screen for eligible papers. Quality appraisal of each study was undertaken using the Critical Appraisal Skills Programme (CASP). Confidence in each finding was assessed using Confidence in the Evidence from Reviews of Qualitative research (CERQual).

RESULTS

Eight qualitative studies (reported in eleven papers and including seventy six myeloma patients) were selected in the final sample for evidence synthesis. Four themes were identified relating to patients' feeling 'dead', disconnecting and isolating themselves, cognitive impairment and engagement with exercise and its benefits in recovery.

CONCLUSIONS

The burden of cognitive functioning among myeloma patients was often under detected. Nurses should ask patients regularly about their memory and any challenges they may be experiencing to their concentration and recall, Exercise during the transplant process can help improve patients' recovery, both physically and psychologically. A structured exercise programme developed by a physiotherapist to suit the needs of each patient should be standard practice in the transplant process.

Daratumumab augments alloreactive natural killer cell cytotoxicity towards CD38+ multiple myeloma cell lines in a biochemical context mimicking tumour microenvironment conditions

Natural killer (NK) cell-based immunotherapy is a promising novel approach to treat cancer. However, NK cell function has been shown to be potentially diminished by factors common in the tumor microenvironment (TME). In this study, we assessed the synergistic potential of antibody-dependent cell-mediated cytotoxicity (ADCC) and killer immunoglobin-like receptor (KIR)-ligand mismatched NK cells to potentiate NK cell antitumor reactivity in multiple myeloma (MM). Hypoxia, lactate, prostaglandin E2 (PGE2) or combinations were selected to mimic the TME. To investigate this, NK cells from healthy donors were isolated and NK cell ADCC capacity in response to MM cells was assessed in flow cytometry-based cytotoxicity and degranulation (CD107a) assays in the presence of TME factors. Hypoxia, lactate and PGE2 reduced cytotoxicity of NK cells against myeloma target cells. The addition of daratumumab (anti-CD38 antibody) augmented NK-cell cytotoxicity against target cells expressing high CD38, but not against CD38 low or negative target cells also in the presence of TME. Co-staining for inhibitory KIRs and NKG2A demonstrated that daratumumab enhanced degranulation of all NK cell subsets. Nevertheless, KIR-ligand mismatched NK cells were slightly better effector cells than KIR-ligand matched NK cells. In summary, our study shows that combination therapy using strategies to maximize activating NK cell signaling by triggering ADCC in combination with an approach to minimize inhibitory signaling through a selection of KIR-ligand mismatched donors, can help to overcome the NK-suppressive TME. This can serve as a platform to improve the clinical efficacy of NK cells.