Treatment of Lymphoid and Myeloid Malignancies by Immunomodulatory Drugs

Thalidomide and its derivatives (lenalidomide, pomalidomide, avadomide, iberdomide hydrochoride, CC-885 and CC-90009) form the family of immunomodulatory drugs (IMiDs). Lenalidomide (CC5013, Revlimid®) was approved by the US FDA and the EMA for the treatment of multiple myeloma (MM) patients, low or intermediate-1 risk transfusion-dependent myelodysplastic syndrome (MDS) with chromosome 5q deletion [del(5q)] and relapsed and/or refractory mantle cell lymphoma following bortezomib. Lenalidomide has also been studied in clinical trials and has shown promising activity in chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL). Lenalidomide has anti-inflammatory effects and inhibits angiogenesis. Pomalidomide (CC4047, Imnovid® [EU], Pomalyst® [USA]) was approved for advanced MM insensitive to bortezomib and lenalidomide. Other IMiDs are in phases 1 and 2 of clinical trials. Cereblon (CRBN) seems to have an important role in IMiDs action in both lymphoid and myeloid hematological malignancies. Cereblon acts as the substrate receptor of a cullin-4 really interesting new gene (RING) E3 ubiquitin ligase CRL4CRBN. This E3 ubiquitin ligase in the absence of lenalidomide ubiquitinates CRBN itself and the other components of CRL4CRBN complex. Presence of lenalidomide changes specificity of CRL4CRBN which ubiquitinates two transcription factors, IKZF1 (Ikaros) and IKZF3 (Aiolos), and casein kinase 1α (CK1α) and marks them for degradation in proteasomes. Both these transcription factors (IKZF1 and IKZF3) stimulate proliferation of MM cells and inhibit T cells. Low CRBN level was connected with insensitivity of MM cells to lenalidomide. Lenalidomide decreases expression of protein argonaute-2, which binds to cereblon. Argonaute-2 seems to be an important drug target against IMiDs resistance in MM cells. Lenalidomide decreases also basigin and monocarboxylate transporter 1 in MM cells. MM cells with low expression of Ikaros, Aiolos and basigin are more sensitive to lenalidomide treatment. The CK1α gene (CSNK1A1) is located on 5q32 in commonly deleted region (CDR) in del(5q) MDS. Inhibition of CK1α sensitizes del(5q) MDS cells to lenalidomide. CK1α mediates also survival of malignant plasma cells in MM. Though, inhibition of CK1α is a potential novel therapy not only in del(5q) MDS but also in MM. High level of full length CRBN mRNA in mononuclear cells of bone marrow and of peripheral blood seems to be necessary for successful therapy of del(5q) MDS with lenalidomide. While transfusion independence (TI) after lenalidomide treatment is more than 60% in MDS patients with del(5q), only 25% TI and substantially shorter duration of response with occurrence of neutropenia and thrombocytopenia were achieved in lower risk MDS patients with normal karyotype treated with lenalidomide. Shortage of the biomarkers for lenalidomide response in these MDS patients is the main problem up to now.

Relationship between lenalidomide dose modification, duration of therapy, and long-term outcomes in patients with myelodysplastic syndromes

Dose reductions or interruptions may be required to manage treatment-associated adverse events among patients with myelodysplastic syndromes (MDS) treated with lenalidomide; such modifications are recommended to sustain therapy and maximize treatment duration. The aim of this retrospective case-control study was to determine the relationship between lenalidomide dose modification (DM), duration of lenalidomide therapy (DOT), and patient outcomes in patients with MDS. Those patients with database follow-up >20months (n=305) were more likely to have received erythropoiesis-stimulating agents (ESAs) (P=0.004), had longer median DOT (P<0.001), and higher rate of DM (P<0.001) versus those with shorter follow-up (n=306). Multivariate analysis indicated that lenalidomide DM (odds ratio [OR] 1.08) and prior ESA treatment (OR 2.40) were significantly associated with longer follow-up; transfusion dependence before lenalidomide initiation was associated with a significantly shorter follow-up (OR 0.60). These data suggest that effective management of lenalidomide treatment using dose reduction and/or delay is associated with longer DOT, which can improve patient outcomes.

[Myelodysplastic syndrome in the elderly: comprehensive geriatric assessment and therapeutic recommendations]

The onset of myelodysplastic syndromes (MDS) is usually around the age of 70. Despite this, most clinical trials are restricted to younger subjects. Thus, the management of elderly patients with MDS is not always optimal. Physiologically, elderly patients show characteristics that differ from those of younger patients and that condition their pharmacological treatment. In this regard, the comprehensive geriatric assessment (CGA) becomes particularly important. This document gathers conclusions from the 1(st) Meeting of Members of the Sociedad Española de Medicina Geriátrica and the Sociedad Española de Hematología y Hemoterapia, with the objective of proposing the establishment of CGA instruments to assist in the decision-making process of elderly patients with MDS. The results of this consensus document will focus on the diagnosis, prognosis, treatment and management of adverse events in this age group.

Management of lower-risk myelodysplastic syndromes: the art and evidence

Myelodysplastic syndromes (MDS) represent a spectrum of bone marrow failure with variable outcome. Patients with "lower-risk" disease have an expected median survival measured in years, and a low risk of leukemia progression. Patients with "higher-risk" MDS, on the other hand, have expected survival measured in months without treatment and rapid leukemia progression. The outcome of those distinct groups can be explained by different underlying disease biology. In clinical practice, patients are stratified into risk groups based on prognostic models, most commonly the International Prognostic Scoring System (IPSS). In higher-risk disease, the standard of care is hypomethylating agents to extend survival and suppress leukemia potential, and consideration of allogeneic stem cell transplantation, which remains the only curative option. Patients classified as having lower-risk disease begin treatment with management focused on ameliorating hematologic deficits, related symptoms, or both. This review of lower-risk MDS highlights the biology of the disease and models for risk stratification. We use a case-based format to discuss current options for treatment, including erythropoiesis-stimulating agents, hypomethylating agents, lenalidomide, immunosuppressive therapy, supportive care, and investigational agents.