Recent data suggest a suboptimal antibody response to COVID-19 vaccination in patients with hematological malignancies. Neutralizing antibodies (NAbs) against SARS-CoV-2 were evaluated in 276 patients with plasma cell neoplasms after vaccination with either the BNT162b2 or the AZD1222 vaccine, on days 1 (before the first vaccine shot), 22, and 50. Patients with MM (n = 213), SMM (n = 38), and MGUS (n = 25) and 226 healthy controls were enrolled in the study (NCT04743388). Vaccination with either two doses of the BNT162b2 or one dose of the AZD1222 vaccine leads to lower production of NAbs in patients with MM compared with controls both on day 22 and on day 50 (p < 0.001 for all comparisons). Furthermore, MM patients showed an inferior NAb response compared with MGUS on day 22 (p = 0.009) and on day 50 (p = 0.003). Importantly, active treatment with either anti-CD38 monoclonal antibodies (Mabs) or belantamab mafodotin and lymphopenia at the time of vaccination were independent prognostic factors for suboptimal antibody response following vaccination. In conclusion, MM patients have low humoral response following SARS-CoV-2 vaccination, especially under treatment with anti-CD38 or belamaf. This underlines the need for timely vaccination, possibly during a treatment-free period, and for continuous vigilance on infection control measures in non-responders.

Asymptomatic multiple myeloma (AMM) is characterized by a constant risk of progression to symptomatic myeloma. To evaluate previously recognized risk factors and to identify high-risk features we analyzed 96 patients with AMM and at least 18 months of follow-up. The progression rate at 1,2, and 3 years was 8%, 15% and 26%, respectively, and the projected 5-year progression rate was 38%. Extensive bone marrow (BM) infiltration, abnormal free light chain (FLC) ratio and serum monoclonal (M)-protein ≥ 3 gr/dl were the most significant factors for progression, whereas the type of heavy (IgG vs IgA) or light chain or immunoparesis of the uninvolved immunoglobulins were not. Abnormal marrow signal of magnetic resonance imaging of the spine was associated with a significant risk of progression (median 15 months, P=0.001). Extensive BM infiltration ≥ 60% (hazard ratio, HR: 13.7, P<0.001) and FLC ratio ≥ 100 (HR: 9, P=0.003) independently identified a 'very high-risk' group, which included 12.5% of patients with AMM and who progressed ≤ 18 months from initial diagnosis. Development of anemia and/or lytic bone lesions were the most common features of symptomatic progression. In conclusion, there is a subgroup of patients who have a substantial risk of progression to symptomatic disease that can be detected at diagnosis (either by extensive BM infiltration ≥ 60% or FLC ratio ≥ 100) and may be considered for immediate treatment.

Clinical trials with carfilzomib have indicated a low but reproducible incidence of cardiovascular and renal toxicities. Among 60 consecutive myeloma patients treated with carfilzomib-based regimens who were thoroughly evaluated for cardiovascular risk factors, 12% (95% confidence interval, 3.8%-20%) experienced a reversible reduction of left ventricular ejection fraction (LVEF) by ≥20%, an objective measure of cardiac dysfunction. The incidence of LVEF reduction was 5% at 3 months, 8% at 6 months, 10% at 12 months, and 12% at 15 months, whereas the respective carfilzomib discontinuation rate unrelated to toxicity was 17%, 35%, 41%, and 49%. The presence of any previously known cardiovascular disease was associated with an increased incidence of cardiac events (23.5% vs 7%; = .07), but there was no association with the dose of carfilzomib or the duration of infusion. Re-treatment with carfilzomib at lower doses was possible. Carfilzomib was commonly associated with a transient reduction of estimated glomerular filtration rate (eGFR) but also improved renal function in 55% of patients with baseline eGFR<60 mL/min/1.73 m. Further investigation is needed to elucidate the underlying mechanisms of carfilzomib-related cardiorenal toxicity.

High circulating activin-A correlates with advanced features of myeloma, supporting the rationale for the use of activin-A antagonists, such as sotatercept in myeloma. The inability of RD to reduce activin-A reveals RD as a good candidate for combination therapies with activin-A antagonists in myeloma.

The urgency of the COVID-19 pandemic has led to accelerated vaccine development within less than a year. Immunocompromised patients with hematological malignancies are more susceptible to COVID-19 and at higher risk of severe complications and worse outcomes compared with general population. In this context, we evaluated the humoral response by determining the titers of neutralizing antibodies (NAbs) against SARS-CoV-2 in patients with Waldenstrom Macroglobulinemia (WM) after vaccination with the BNT162b2 or AZD1222 vaccine. An FDA-approved, ELISA-based methodology was implemented to evaluate NAbs on the day of the first vaccine shot, as well as on day 22 and 50 afterwards. 106 patients with WM (43% males, median age 73 years) and 212 healthy controls (46% males, median age 66 years) who were vaccinated during the same period, at the same center were enrolled in the study (which is registered at www.clinicaltrials.gov as NCT04743388). Our data indicate that vaccination with either 2 doses of the BNT162b2 or 1 dose of the AZD1222 vaccine leads to lower production of NAbs against SARS-CoV-2 in patients with WM compared with controls both on day 22 and on day 50 (P&lt;0.001 for all comparisons). Disease-related immune dysregulation and therapy-related immunosuppression are involved in the low humoral response. Importantly, active treatment with either Rituximab or Bruton's Tyrosine Kinase inhibitors was proven as an independent prognostic factor for suboptimal antibody response following vaccination. In conclusion, patients with WM have low humoral response following COVID-19 vaccination, which underlines the need for timely vaccination ideally during a treatment-free period and for continuous vigilance on infection control measures.