Molecular and cellular features of CTLA-4 blockade for relapsed myeloid malignancies after transplantation

Relapsed myeloid disease after allogeneic stem cell transplantation (HSCT) remains largely incurable. We previously demonstrated the potent activity of immune checkpoint blockade in this clinical setting with ipilimumab or nivolumab. To define the molecular and cellular pathways by which CTLA-4 blockade with ipilimumab can reinvigorate an effective graft-versus-leukemia (GVL) response, we integrated transcriptomic analysis of leukemic biopsies with immunophenotypic profiling of matched peripheral blood samples collected from patients treated with ipilimumab following HSCT on the Experimental Therapeutics Clinical Trials Network 9204 trial. Response to ipilimumab was associated with transcriptomic evidence of increased local CD8+ T-cell infiltration and activation. Systemically, ipilimumab decreased naïve and increased memory T-cell populations and increased expression of markers of T-cell activation and costimulation such as PD-1, HLA-DR, and ICOS, irrespective of response. However, responding patients were characterized by higher turnover of T-cell receptor sequences in peripheral blood and showed increased expression of proinflammatory chemokines in plasma that was further amplified by ipilimumab. Altogether, these data highlight the compositional T-cell shifts and inflammatory pathways induced by ipilimumab both locally and systemically that associate with successful GVL outcomes. This trial was registered at www.clinicaltrials.gov as #NCT01822509.

Developments in chemotherapy for the treatment of acute myeloid leukemia

Mark Drummond obtained his medical degree from the University of Glasgow (UK) and since then has trained as a hematologist in the West of Scotland and the Canterbury District Health Board (Christchurch, New Zealand) and back at Glasgow University, where he also gained a PhD in chronic myeloid leukemia. He is currently a consultant hematologist and honorary senior lecturer at the Beatson Cancer Centre (Glasgow, UK) as well as an investigator on multiple UK and international clinical trials.

Here he talks to Commissioning Editor Jennifer Straiton, commenting on the recent announcement from the Scottish Medicines Consortium, regarding their acceptance of the use of the combination chemotherapy treatment Vyxeos^® (daunorubicin and cytarabine) for the treatment of high-risk acute myeloid leukemia in adults. He then discusses the ongoing and future clinical trials in this disease area and then turns to more personalized treatments.