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CLINICAL NEWS On Location 2018 ASH Annual Meeting Continued from page 38 treatment,” Dr. Garcia-Manero stressed. The most commonly reported grade 3/4 adverse events (AEs) in both cohorts included infection, rash, musculoskeletal pain, and transaminitis. The safety and efficacy results observed in this trial suggest that “the incorporation of immune checkpoint inhibitor therapy is feasible in patients with MDS,” Dr. Garcia- Manero concluded. There was a potential relationship between PD1 expression and response, but he noted that this needs to be explored further. The results also need to be confirmed in larger randomized trials in the frontline and relapsed settings, he added. Atezolizumab Plus Azacitidine Next, Aaron Gerds, MD, from Cleveland Clinic’s Taussig Cancer Institute, shared findings from a trial evaluating atezolizumab, with or without azacitidine, in patients with HMA-naïve, higher-risk MDS (defined as intermediate, high, or very high-risk per the Revised International Prognostic Sco- ring System) or who had disease that was relapsed/refractory to prior HMA therapy. After researchers observed a high number of deaths within the first three treatment cycles in the HMA-naïve cohort, the study was terminated early. This phase Ib trial enrolled 42 adult patients into three cohorts: • cohort A1: HMA-failure MDS and atezolizumab alone (n=10) • cohort B1: HMA-failure MDS and atezolizumab plus azacitidine for 6 cycles, followed by atezolizumab maintenance alone (n=11) • cohort C1/C2: HMA-naïve MDS and atezolizumab plus azacitidine until clinical benefit (n=21) In the safety analysis, grade 3/4 AEs were common, occurring in 50 percent (n=5/10), 91 percent (n=10/11), and 57 percent (n=12/21) of patients in cohorts A, B, and C1/2, respectively. Immune-related AEs included infusion-related reactions and hypothyroidism in cohort A and rash and hemolysis in cohorts B and C. There were 21 deaths across the three cohorts: seven in cohort A, eight in cohort B, and six in cohort C1/C2. Most deaths were related to progressive disease in cohorts A and B, but all deaths in cohort C were attributed to AEs. Deaths occurred early in the HMA- naïve patients in cohort C1/C2, Dr. Gerds reported. All six occurred within the first three treatment cycles, three of which oc- curred within the first treatment cycle. When asked about potential mecha- nisms for the increased toxicity with atezolizumab, compared with other immunotherapies, Dr. Gerds noted that there was “no clear biologic plausibility [to explain this association], although the fact that antibiotic prophylaxis was left to investigator discretion may have led to an increased infection risk.” No patients with HMA-failure MDS responded to treatment with atezolizumab (cohort A), while only one patient with HMA-failure MDS responded to treat- ment with atezolizumab plus azacitidine (cohort B). In cohort C, however, 13 patients responded to treatment, for an ORR of 62 percent. Median OS was not reached in cohort C but was 177 days in cohort A and 361 days in cohort B. Six patients with HMA-naïve MDS are continuing to receive the atezolizumab/ azacitidine combination, and the investiga- tors also are continuing to follow patients who discontinued the study early to identify potential markers of response. “The number of deaths we saw early was certainly concerning,” Dr. Gerds said. However, given the responses to atezoli- zumab plus azacitidine seen in the HMA- naïve population, he added that “a better understanding of the different toxicity profiles observed between HMA-naive and HMA-failure patients with higher-risk MDS patients is crucial for future developments of this combination.” The authors of the first trial report rela- tionships with Bristol-Myers Squibb, which supported the trial. The authors of the second trial report relationships with Roche, which supported the trial. REFERENCES Garcia-Manero G, Sasaki K, Montalban-Bravo G, et al. A phase II study of nivolumab or ipilimumab with or without azacitidine for patients with myelodysplastic syndrome (MDS). Abstract #465. Presented at the 2018 ASH Annual Meeting, December 2, 2018; San Diego, CA. Gerds A, Scott B, Greenberg P, et al. PD-L1 blockade with atezolizumab in higher-risk myelodysplastic syndrome: an initial safety and efficacy analysis. Abstract #466. Presented at the 2018 ASH Annual Meeting, December 3, 2018; San Diego, CA. Transplant or No Transplant for Older, Fit Patients With MDS? Hematopoietic cell transplantation (HCT) with reduced-intensity conditioning improved overall survival (OS) in older patients with advanced myelodysplastic syndromes (MDS), compared with OS in patients who did not undergo transplant, according to a non-randomized report from the Myelodysplastic Dysplastic Syn- dromes Transplant-Associated Outcomes (MDS-TAO) study. The results, which were presented at the 2018 ASH Annual Meeting by Gregory A. Abel, MD, MPH, from Dana- Farber Cancer Institute in Boston, suggest that transplant should be considered for older, fit patients. This observational study included patients between the ages of 60 and 75 with advanced MDS or chronic mono- myelocytic leukemia who presented at Dana-Farber. Patients who were con- sidered eligible for HCT, met the study inclusion criteria (int-2/high disease per the International Prognostic Scoring Sys- tem [IPSS], poor-risk cytogenetics, or the severe cytopenia/platelet or red blood cell transfusion–dependence), and were will- ing to undergo transplant were enrolled in the trial. Between May 2011 and May 2018, 290 patients were enrolled. 24 patients had fewer than 90 days of follow-up and were excluded from the final analysis. 40 ASH Clinical News The median age among the remaining 266 patients was 69 (range = 60-75 years), and most had favorable-risk cytogenetics (53%). Most patients had either int-1 or int-2 disease (44% and 36%, respectively). A total of 102 participants underwent transplant (within a median of 4.6 months from enrollment; range not reported) and 164 underwent treatment without HCT. The researchers found that patients who had higher-risk disease (int-2/high on the IPSS) at baseline were more likely to undergo HCT (65% vs. 35%; p=0.0003), after adjusting for age, gender, Eastern Cooperative Oncology Group (ECOG) performance status, IPSS stage and cyto- genetics, and year of trial consent. The study used a landmark analysis at five months to estimate OS among patients who were alive for at least five months and received HCT, versus patients who did not (landmark cohort). During the study observation period, 45 patients in the HCT group and 98 in the non-HCT group had died, leaving a final cohort of 123 surviving patients. The median follow-up among sur- vivors was 31 months (range = 1.9-84 months), and the median follow-up for patients alive and not yet transplanted (n=66) was 24 months (range = 1.9-82 months). In a multivariable analysis, patients Attendees browse the booths at ASH Central. who underwent transplant had a signifi- cantly lower risk of death (hazard ratio [HR] for OS = 0.63; 95% CI 0.42-0.96; p=0.03). The investigators evaluated other patient characteristics (disease stage, ECOG score, age, gender, year of consent) and found that only poor-risk cytoge- netics were associated with worse OS (HR=1.86; 95% CI 1.15-3.00; p=0.006); “In this [study] of fit elderly patients with advanced MDS, a treatment strategy that included HCT was associated with better OS,” the authors concluded. The study’s findings are limited by the lack of a randomized design, the potential for selection bias, and the researchers noted that subgroup analyses to evaluate whether molecular characteristics or other disease factors affect survival outcomes are ongoing. The authors report relationships with H3 Biosciences, Celgene, Arog, AbbVie, Agios, Novartis, ARIAD, Blueprint Medicines, GlycoMimetics, Millennium, Prometheus, and Miltenyi Biotech. ● REFERENCE Abel GA, Kim HT, Steensma DP, et al. Survival after hematopoietic stem cell transplantation in an older, fit cohort of patients with advanced myelodysplastic syndromes: the MDS-TAO study. Abstract #972. Presented at the 2018 ASH Annual Meeting, December 3, 2018; San Diego, CA. February 2019