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CLINICAL NEWS transfusion requirement: • ≥6 units per 8 weeks: 9.1% vs. 3.0% (odds ratio [OR] = 3.2; 95% CI 0.37- 27.7; p=0.27) • <6 units per 8 weeks: 59.8% vs. 20.9% (OR=5.61; 95% CI 2.4-13.1; p<0.001) A larger proportion of patients in the lus- patercept group also achieved the second- ary endpoint of transfusion-independence for at least 12 weeks (28.1% vs. 7.9% at 24-week follow-up and 33.3% vs. 11.8% at 48-week follow-up; p<0.0003 for both). The median duration of response was 30.6 weeks (range = 20.6-40.6 weeks) in the lus- patercept group, compared with 13.6 weeks (range = 9.1-54.9 weeks) in the placebo group (p value not reported). Secondary endpoints such as erythroid response and mean change in Hb levels also significantly favored luspatercept (p<0.0001 for both), with luspatercept responders experiencing “a greater sustained rise in Hb concentration from baseline pre-transfusion levels, compared with nonresponders or placebo-treated patients,” he added. “Overall, approximately 40 percent of luspatercept-treated patients remained transfusion-free at one year,” Dr. List reported. The proportion of patients discontinu- ing treatment due to adverse events (AEs) was comparable in both arms (8.5% and 7.9%, respectively). Treatment-emergent AEs that were reported more frequently in the luspatercept arm than the placebo arm included fatigue, diarrhea, asthenia, nausea, dizziness, and back pain. “Of course, with anything that’s going to promote cell survival, we worry about leukemia, but there was no difference in the frequency of acute leukemia,” Dr. List added. Four luspatercept-treated patients (2%) and one placebo-treated patient (1.3%) pro- gressed to acute myeloid leukemia during the study follow-up period. The study’s findings are limited to patients with lower-risk MDS with ring sideroblasts, and the results may not be generalizable to patients with higher-risk MDS or those without ring sideroblasts. Dr. List noted that the phase III COMMAND trial is comparing luspatercept with placebo in patients with and without ring sideroblasts who are ESA-naïve; results from this study may provide more answers about luspatercept’s role in the larger MDS population. BELIEVE In the randomized, double-blind, pla- cebo-controlled BELIEVE trial, patients with beta thalassemia who received lus- patercept had lower transfusion burdens, compared with those receiving placebo. The results, presented by lead author Maria Domenica Cappellini, MD, from the University of Milan in Italy, suggest that luspatercept is a potential new thera- py for “this very demanding disease.” Luspatercept holds the promise of alleviating the treatment burden for pa- tients, she added. “These are young adult patients [being transfused] three units of blood every three weeks, so [the reduction in transfusion burden with luspatercept] has a substantial impact.” Patients were included in BELIEVE if they had beta thalassemia or Hb E/beta thalassemia and were RBC transfusion- dependent, defined as requiring regular transfusions (6-20 RBC units) in the 24 weeks prior to randomization and having no transfusion-free period ≥35 days during that time. Participants were then randomized 2:1 to receive either luspatercept at a start- ing dose level of 1 mg/kg, with titration up to 1.25 mg/kg, or placebo adminis- tered subcutaneously every three weeks for at least 48 weeks. In both treatment arms, patients continued to receive RBC transfusions and iron chelation therapy as needed. Crossover to the luspatercept arm was allowed after unblinding. As of May 11, 2018 (data cutoff), 336 patients were treated: 224 in the luspa- tercept arm and 112 in the placebo arm. Participants’ median age was 30 years (range = 18-66 years), and 58 percent of patients were female. Most patients (58% of each arm) had undergone splenectomy prior to study randomization. After up to three years of follow-up, 48 of 224 patients (21.4%) in the luspater- cept arm achieved the primary endpoint of RBC transfusion reduction (defined as a ≥33% reduction in RBC transfusion burden, with a reduction of ≥2 RBC units from baseline, during weeks 13-24). In the placebo group, just five of 112 patients (4.5%) experienced a clinically meaning- ful reduction in transfusion dependence (OR=5.79; p<0.001). In addition, 158 of 224 luspatercept- treated patients (70.5%) achieved a ≥33-percent reduction in RBC transfu- sion requirements during any consecutive 12 weeks of treatment, while 33 of 112 placebo-treated patients (29.5%) achieved the same result (p<0.001). The authors also observed statistically significant differences in favor of luspater- cept for all other transfusion burden–related secondary endpoints, including: • ≥33% reduction in transfusion burden at weeks 37-48: 19.6% (44 of 224 luspatercept-treated patients) vs. 3.6% (4 of 112 placebo-treated patients; p<0.001) from Saarland University Medical School in Germany, who presented the findings at the 2018 ASH Annual Meeting. The FLYER trial was based on results from an earlier study in which patients with an age-adjusted International Prog- nostic Index (aaIPI) score of 0 without bulky disease had high rates of three-year event-free survival (EFS) and progression- free survival (PFS) with a standard regimen of rituximab plus CHOP chemotherapy. “Our aim was to see if we could maintain efficacy and reduce toxicity in patients meeting these criteria by reducing the REFERENCES • ≥50% reduction in transfusion burden at weeks 13-24: 7.6% (17/224) vs. 1.8% (2/112; p=0.03) 1. Fenaux P, Platzbecker U, Mufti GJ, et al. The MEDALIST trial: results of a phase 3, randomized, double-blind, placebo-controlled study of Luspatercept to treat anemia in patients with very low-, low-, or intermediate-risk myelodysplastic syndromes (MDS) with ring sideroblasts (RS) who require red blood cell (RBC) transfusions. Abstract #1. Presented at the 2018 ASH Annual Meeting, December 2, 2018; San Diego, CA. • ≥50% reduction in transfusion burden at weeks 37-48: 10.3% (24/224) vs. 0.9% (1/112; p=0.002) 2. Cappellini MD, Viprakasit V, Taher A, et al. The BELIEVE trial: results of a phase 3, randomized, double-blind, placebo-controlled study of luspatercept in adult beta thalassemia patients who require regular red blood cell (RBC) transfusions. Abstract #163. Presented at the 2018 ASH Annual Meeting, December 1, 2018; San Diego, CA. Four Cycles as Effective as Six Cycles of Chemotherapy for Favorable-Risk DLBCL While young patients with diffuse large B-cell lymphoma (DLBCL) are typically treated with six cycles of R-CHOP (ritux- imab, cyclophosphamide, doxorubicin, vincristine, prednisone), results from the FLYER trial suggest that a subgroup of young patients with favorable-prognosis disease can achieve the same clinical ben- efit with four cycles of R-CHOP plus two cycles of rituximab monotherapy. “With a shorter duration of chemother- apy, patients are back to daily life with their families and back to work more quickly,” said lead study author Viola Poeschel, MD, Among all patients, the median number of RBC units received in the 12 weeks prior to study treatment was six (range = 3-14), and the mean reduction in transfusion burden from baseline to weeks 13 to 24 was 1.35 units (p<0.001), the authors added. “Luspatercept achieved a reduction in transfusion burden across any 12- or 24-week period – the most important ob- servation, because each [patient’s disease] is different and may respond in a different time and outside of the fixed observation period,” Dr. Cappellini stressed. AEs occurring with luspatercept were “generally mild to moderate and manage- able, without requiring dose modifications or interruptions,” Dr. Cappellini reported. Common AEs included bone pain and thrombotic events, including stroke. No patient deaths were reported for those treated with luspatercept. The findings of this placebo-controlled trial will need to be compared with available management strategies for beta thalassemia, including transfusions – as well as gene therapy options on the horizon. “In my point of view, to be really efficacious, gene therapy must be a cure,” Dr. Cappellini said. “We are not going to perform gene therapy for reducing transfusion burden – that’s not the scope of the treatment. There is still a ways to go to achieve that point.” The authors of the MEDALIST and BELIEVE trials report financial relation- ships with Acceleron, the manufacturer of luspatercept. Celgene and Acceleron sup- ported both trials. number of CHOP cycles,” Dr. Poeschel explained. In this trial, the researchers random- ized patients aged 18 to 60 years who had an aaIPI of 0 and non-bulky disease (<7.5 cm) to receive either six cycles of R-CHOP (n=295) or four cycles of R-CHOP plus two cycles of rituximab (n=293). This was a “relatively young patient population” with a median age of 48 years (range not report- ed), and demographics were well balanced between each group, the authors noted. Most patients had stage I or II disease and were considered to have low-risk disease. At a median follow-up of 66 months (range not reported), the rates of three-year PFS, EFS, and overall survival (OS) were similar between each group: • PFS: 94% with 6 cycles vs. 96% with 4 cycles (hazard ratio [HR] = 0.9; 95% CI 0.5-1.6; p=0.8) • EFS: 89% vs. 89% (HR=1.0; 95% CI 0.7-1.6; p=0.9) • OS: 98% vs. 99% (HR=0.8; 95% CI 0.4-1.9; p=0.67) All patients did well with R-CHOP, the re- searchers noted, with a similar low frequency of relapses in each arm: 4 percent of patients in the four-cycle group and 5 percent in the Continued on page 25 ASHClinicalNews.org ASH Clinical News 19