In this trial of the treatment of newly diagnosed multiple myeloma, we compared a protocol that entailed a hematopoietic stem-cell autograft followed by an allograft from an HLA-identical sibling with a protocol of tandem autografts. We enrolled 162 consecutive patients with newly diagnosed myeloma who were 65 years of age or younger and who had at least one sibling. All patients were initially treated with vincristine, doxorubicin, and dexamethasone, followed by melphalan and autologous stem-cell rescue. Patients with an HLA-identical sibling then received nonmyeloablative total-body irradiation and stem cells from the sibling. Patients without an HLA-identical sibling received two consecutive myeloablative doses of melphalan, each of which was followed by autologous stem-cell rescue. The primary end points were overall survival and event-free survival. After a median follow-up of 45 months (range, 21 to 90), the median overall survival and event-free survival were longer in the 80 patients with HLA-identical siblings than in the 82 patients without HLA-identical siblings (80 months vs. 54 months, P=0.01; and 35 months vs. 29 months, P=0.02, respectively). Among patients who completed their assigned treatment protocols, treatment-related mortality did not differ significantly between the double-autologous-transplant group (46 patients) and the autograft–allograft group (58 patients, P=0.09), but disease-related mortality was significantly higher in the double-autologous-transplant group (43% vs. 7%, P<0.001). The cumulative incidence rates of grades II, III, and IV graft-versus-host disease (GVHD) combined and of grade IV GVHD in the autograft–allograft group were 43% and 4%, respectively. Overall, 21 of 58 patients (36%) were in complete remission after a median follow-up of 38 months (range, 10 to 72) after allografting. Of the 46 patients who received two autografts, 25 (54%) died. Among patients with newly diagnosed myeloma, survival in recipients of a hematopoietic stem-cell autograft followed by a stem-cell allograft from an HLA-identical sibling is superior to that in recipients of tandem stem-cell autografts. (ClinicalTrials.gov number, NCT00415987.)

Hematological toxicity is the most common adverse event after chimeric antigen receptor (CAR) T-cell therapy. Cytopenias can be profound and long-lasting and can predispose for severe infectious complications. In a recent worldwide survey, we demonstrated that there remains considerable heterogeneity in regard to current practice patterns. Here, we sought to build consensus on the grading and management of immune effector cell–associated hematotoxicity (ICAHT) after CAR T-cell therapy. For this purpose, a joint effort between the European Society for Blood and Marrow Transplantation (EBMT) and the European Hematology Association (EHA) involved an international panel of 36 CAR T-cell experts who met in a series of virtual conferences, culminating in a 2-day meeting in Lille, France. On the basis of these deliberations, best practice recommendations were developed. For the grading of ICAHT, a classification system based on depth and duration of neutropenia was developed for early (day 0-30) and late (after day +30) cytopenia. Detailed recommendations on risk factors, available preinfusion scoring systems (eg, CAR-HEMATOTOX score), and diagnostic workup are provided. A further section focuses on identifying hemophagocytosis in the context of severe hematotoxicity. Finally, we review current evidence and provide consensus recommendations for the management of ICAHT, including growth factor support, anti-infectious prophylaxis, transfusions, autologous hematopoietic stem cell boost, and allogeneic hematopoietic cell transplantation. In conclusion, we propose ICAHT as a novel toxicity category after immune effector cell therapy, provide a framework for its grading, review literature on risk factors, and outline expert recommendations for the diagnostic workup and short- and long-term management.

The European Myeloma Network provides recommendations for the management of the most common complications of multiple myeloma. Whole body low-dose computed tomography is more sensitive than conventional radiography in depicting osteolytic disease and thus we recommend it as the novel standard for the detection of lytic lesions in myeloma (grade 1A). Myeloma patients with adequate renal function and bone disease at diagnosis should be treated with zoledronic acid or pamidronate (grade 1A). Symptomatic patients without lytic lesions on conventional radiography can be treated with zoledronic acid (grade 1B), but its advantage is not clear for patients with no bone involvement on computed tomography or magnetic resonance imaging. In asymptomatic myeloma, bisphosphonates are not recommended (grade 1A). Zoledronic acid should be given continuously, but it is not clear if patients who achieve at least a very good partial response benefit from its continuous use (grade 1B). Treatment with erythropoietic-stimulating agents may be initiated in patients with persistent symptomatic anemia (hemoglobin <10g/dL) in whom other causes of anemia have been excluded (grade 1B). Erythropoietic agents should be stopped after 6–8 weeks if no adequate hemoglobin response is achieved. For renal impairment, bortezomib-based regimens are the current standard of care (grade 1A). For the management of treatment-induced peripheral neuropathy, drug modification is needed (grade 1C). Vaccination against influenza is recommended; vaccination against streptococcus pneumonia and hemophilus influenza is appropriate, but efficacy is not guaranteed due to suboptimal immune response (grade 1C). Prophylactic aciclovir (or valacyclovir) is recommended for patients receiving proteasome inhibitors, autologous or allogeneic transplantation (grade 1A).

The full potential of a graft-versusmyeloma effect after allogeneic hematopoietic cell transplantation (HCT) for patients with multiple myeloma (MM) has not been realized because of excessive early transplantation-related mortality (TRM) with conventional HCT. Autologous HCTs have been characterized by almost universal disease recurrences. The current trial combined autologous HCT with subsequent nonmyeloablative allogeneic HCT to maintain the benefits of both approaches with acceptable toxicity. Fifty-four patients, 52 years of age (median; range, 29-71 years), with previously treated stage II or III MM (52% refractory or relapsed disease) were given melphalan 200 mg/m2 and autologous HC transplants. Regimen-related toxicities after autologous HCT were moderate with a median of 6 days of neutropenia, 7 days of hospitalization, and 1 death from infection. Forty to 229 days later (median, 62 days), 52 patients received a single fraction dose of 2 Gy total body irradiation and HC transplants from HLA-identical siblings with postgrafting immunosuppression with mycophenolate mofetil (MMF) and cyclosporine (CSP). Patients experienced medians of 0 days of hospitalization, neutropenia, and thrombocytopenia. Sustained engraftment was uniform. With a median follow-up of 552 days after allografting, overall survival is 78%. One patient (2%) died before day 100 from disease progression. Thirty-eight percent of patients developed acute graft-versus-host disease (GVHD; grade II in all but 4 cases) and 46% chronic GVHD requiring therapy. Tumor responses occurred slowly. Thus far, 57% of patients have achieved complete remissions and 26% have achieved partial remissions for an overall response of 83%. Despite being evaluated in elderly patients with MM, this 2-step approach has reduced the acute toxicities of allogeneic HCT while achieving potent antitumor activities.

Increasing age has been historically implicated in higher mortality after high-dose allogeneic hematopoietic cell transplantation (HCT) for patients with hematologic malignancies.¹ Such transplants are preceded by intense, cytotoxic conditioning regimens aimed at reducing tumor burden. The risk of organ toxicities has limited the use of high-dose regimens to younger patients in good medical condition. Therefore, age cutoffs of 55 to 60 years have been in place for decades for high-dose HCT. This excluded the vast majority of patients from allogeneic HCT, given that median ages of patients at diagnoses of most hematologic malignancies range from 65 to 70 years.^2,3

Complete response (CR) was an uncommon event in elderly myeloma patients until novel agents were combined with standard oral melphalan-prednisone. This analysis assesses the impact of treatment response on progression-free survival (PFS) and overall survival (OS). We retrospectively analyzed 1175 newly diagnosed myeloma patients, enrolled in 3 multicenter trials, treated with melphalan-prednisone alone (n = 332), melphalan-prednisone-thalidomide (n = 332), melphalan-prednisone-bortezomib (n = 257), or melphalan-prednisone-bortezomib-thalidomide (n = 254). After a median follow-up of 29 months, the 3-year PFS and OS were 67% and 27% (hazard ratio = 0.16; P < .001), and 91% and 70% (hazard ratio = 0.15; P < .001) in patients who obtained CR and in those who achieved very good partial response, respectively. Similar results were observed in patients older than 75 years. Multivariate analysis confirmed that the achievement of CR was an independent predictor of longer PFS and OS, regardless of age, International Staging System stage, and treatment. These findings highlight a significant association between the achievement of CR and long-term outcome, and support the use of novel agents to achieve maximal response in elderly patients, including those more than 75 years. This trial was registered at www.clinicaltrials.gov as #NCT00232934, #ISRCTN 90692740, and #NCT01063179.