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CLINICAL NEWS On Location 2018 ASH Annual Meeting As of August 17, 2018 (data cutoff), five patients (4.1%) remained on treat- ment. The most common reasons for discontinuation were: disease progression (55.1%) and adverse events (AEs; 32.2%). At three-month follow-up, the overall response rate (ORR; primary endpoint) was 26.2 percent, including: • partial response (PR): 19.7% • very good PR (VGPR): 4.9% • stringent complete response (sCR): 1.6% The two patients who achieved sCRs also had minimal residual disease–negative status, the authors reported, and an ad- ditional 13.1 percent of patients achieved a minimal response (MR). Dr. Chari noted that the time to response was “quite short – only one month – and the median duration of response was 4.4 months.” In subgroup analyses, response rates were similar, regardless of the last prior therapy. The median progression-free survival (PFS) and overall survival (OS) were 3.7 months and 8.6 months, respectively ( TABLE 4 ). Importantly, Dr. Chari said, “the median overall survival was 15.6 months for both patients who achieved a minimal response or a partial response – highlighting the importance of looking at both partial and minimal responses in heavily pretreated patient populations.” Median duration of selinexor treat- ment was 9 weeks (range = 1-60+ weeks), and 79.7 percent of patients required a dose modification – most of which oc- curred in the first two cycles. The most common non-hematologic AEs included nausea, fatigue, weight loss, anorexia, vomiting, and diarrhea. The most com- mon hematologic AE was thrombocyto- penia (67.5%), followed by anemia (48%). AEs were generally reversible, and the investigators found that the side effects of selinexor were dose- and schedule- TABLE 4. Survival Estimates According to Treatment Response All Patients (n=122) ≥PR (n=32) ≥MR (n=48) SD (n=48) PD/NE (n=26) Median progression-free survival 3.7 months 5.3 months 4.6 months 2.8 months 1.1 months Median overall survival 8.6 months 15.6 months 15.6 months 5.9 months 1.7 months PR = partial response; MR = minimal response; SD = stable disease; PD = progressive disease; NE = not estimable dependent. Because selinexor crosses the blood-brain barrier, they stressed the importance of early identification, frequent assessment, and implementa- tion of supportive care measures for AE management. Limitations of the study include the lack of a comparator or placebo arm, as well as a relatively small number of par- ticipants included in the final cohort. Dr. Chari added that ongoing studies are inves- tigating potential biomarkers of selinexor resistance, as well as selinexor in combina- tion with various MM backbone agents. The authors report financial relation- ships with Novartis, Array Biopharma, Celgene, Amgen, Pharmacyclics, Takeda, Janssen, Millennium Takeda, Bristol-Myers Squibb, Sanofi, Jazz Pharmaceuticals, and Karyopharm Therapeutics (which spon- sored the trial). REFERENCE Chari A, Vogl DT, Dimopoulos MA, et al. Results of the pivotal STORM study (part 2) in penta-refractory multiple myeloma (MM): deep and durable responses with oral selinexor plus low dose dexamethasone in patients with penta-refractory MM. Abstract #598. Presented at the 2018 ASH Annual Meeting, December 3, 2018; San Diego, CA. ECHELON-2: Brentuximab Vedotin Combination Outperforms CHOP for Peripheral T-Cell Lymphomas Results from the phase III ECHELON-2 trial showed that brentuximab vedotin added to a combination of cyclophos- phamide, doxorubicin, and prednisone (BV+CHP) nearly doubled progression- free survival (PFS) for patients with peripheral T-cell lymphomas (PTCLs), compared with treatment involving a standard regimen of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). Steven Horwitz, MD, from the Memorial Sloan Kettering Cancer Center in New York, presented the results at the 2018 ASH Annual Meeting. “CHOP and CHOP-like regimens are the most common frontline treatments of PTCL, but these regimens do not pro- duce a durable remission in the majority of [PTCL] subtypes, including ALK- positive systemic anaplastic large cell lymphoma (sALCL) and other CD30- positive PTCLs,” Dr. Horwitz explained. “ECHELON-2 is the first prospective trial in peripheral T-cell lymphoma to show an overall benefit over CHOP, [with a] 29-percent reduction in the risk of disease progression and a 34-percent reduction in the risk of death.” Based on these data, the U.S. Food and Drug Administration expanded brentux- imab vedotin’s indication in November 2018 to include the firstline treatment of adult patients with PTCLs – marking the first approval for this indication. The double-blind, randomized, multi- center ECHELON-2 trial enrolled 452 38 ASH Clinical News patients from 132 sites in 17 countries. All participants had newly diagnosed, CD30-positive PTCLs and an Eastern Cooperative Oncology Group perfor- mance status score of ≤2. People with a history of other primary invasive malignancy or progressive multifocal leukoencephalopathy were excluded from the trial. After stratifying patients according to histologic subtype and International Prognostic Index score, investigators randomly assigned patients to receive six to eight 21-day cycles of either: • BV+CHP: brentuximab vedotin 1.8 mg/kg plus cyclophosphamide 750 mg/m 2 , doxorubicin 50 mg/m 2 , and prednisone 100 mg on days 1-5 (n=226) • CHOP: cyclophosphamide 750 mg/m 2 , doxorubicin 50 mg/m 2 , vincristine 1.4 mg/m 2 , and prednisone 100 mg on days 1-5 (n=226) The researchers reported that baseline characteristics were similar between both arms: The median age was 58 years (range not reported) and most patients had stage III/IV disease. sALCL was the most common PTCL subtype (70%), fol- lowed by PTCL-not otherwise specified (16%) and angio-immunoblastic T-cell lymphoma (12%). As of August 15, 2018 (data cutoff), 449 of the 452 randomized patients received at least one dose of study treatment. Most of the patients –85 percent and 79 percent of patients in the BV+CHP and CHOP groups, respec- tively – completed treatment. In the BV+CHP group, discontinuation was most often related to adverse events (AEs; 7%) or disease progression (3%); in the CHOP group, most patients discon- tinued due to disease progression (12%) and AEs (7%). After a median follow-up of 36.2 months (range not reported), 83 per- cent of BV+CHP-treated participants responded, compared with 72 percent of CHOP-treated participants (p=0.003), and complete responses were more common in the BV+CHP group (68% vs. 56%; p=0.007). “The superiority of [BV+CHP] is not due to the poor response of CHOP, as the CHOP curves were better than anticipated or histori- cally reported,” Dr. Horwitz clarified. The median PFS (primary endpoint) was 48.2 months (range = 35.2 months to not evaluable) in the BV+CHP group and 20.8 months (range = 12.7-47.6 months) in the CHOP group. This trans- lated to a 29-percent lower risk of disease progression or death with BV+CHP (hazard ratio = 0.71; 95% CI 0.54-0.93; p=0.01). The rate of three-year PFS also ap- peared to be higher in the BV+CHP group (57% vs. 44%; p value not provided). Median overall survival (OS; secondary endpoint) also appeared to be higher in the BV+CHP group (not reached vs. 17.5 months; ranges and p value not reported). The incidence of AEs was consistent between groups, and with the known safety profiles of each treatment regimen, the researchers added. Nearly all patients in each arm experienced an AE (99% for BV+CHP and 98% for CHOP). The most common treatment-related AEs were nausea (46% for BV+CHP and 38% for CHOP), peripheral sensory neuropathy (45% and 41%), and neutropenia (38% in each arm). Grade ≥3 AEs reported in the BV+CHP group included neutropenia (33%), febrile neutropenia (17%), and anemia (12%). AEs were fatal for seven patients (3%) on the brentuximab vedotin arm and nine (4%) on the CHOP arm. Patients with ALK-positive sALCL generally saw the greatest improvement in PFS and OS with BV+CHP over CHOP, Dr. Horwitz reported, but he noted the study was not powered to com- pare efficacy among individual subtypes, which may be a limitation of the analysis. The authors reported financial rela- tionships with Seattle Genetics, which sponsored the trial. ● REFERENCE Horwitz S, O’Connor O, Pro B, et al. The ECHELON-2 trial: results of a randomized, double-blind, active-controlled phase 3 study of brentuximab vedotin and CHP (A+CHP) versus CHOP in the frontline treatment of patients with CD30+ peripheral T-cell lymphomas. Abstract #997. Presented at the 2018 ASH Annual Meeting, December 3, 2018; San Diego, CA. January 2019 Annual Meeting Edition