Real-World Experience of Adults With Acute Myeloid Leukemia on Hypomethylating Agents With or Without Venetoclax at a Comprehensive Cancer Center.

Background: Venetoclax (VEN) in combination with hypomethylating agent (HMA) therapy is a standard treatment option for patients with newly diagnosed acute myeloid leukemia (AML); however, data are limited in the relapsed or refractory (R/R) populations and in those with poor-risk disease. A retrospective review was conducted involving patients with AML who received HMA alone or in combination with VEN (VEN + HMA). Methods: VEN + HMA was compared to HMA alone in first-line and R/R settings. Patients were stratified by specific HMA and line of therapy. The primary endpoint was overall response rate (ORR) up to 6 months from start of treatment. Results: Fifty-two patients were evaluated for efficacy and 78 patients for safety. ORR was 67% (VEN + HMA) versus 80% (HMA) in the first line and 50% versus 22% in R/R setting. A greater clinical benefit was seen with VEN + HMA compared to HMA in both lines of therapy (first-line: 87% vs. 80%; R/R: 75% vs. 67%). The median duration of response was longer with VEN + HMA first-line, but shorter in the R/R setting compared to HMA (8.3 vs. 7.2 months and 2.5 vs. 3.7 months, respectively). Of the 32 patients who responded to therapy, 63% had a complex karyotype. Survival benefits were greater with VEN + HMA in both lines of therapy, although not statistically significant. Grade 3/4 neutropenia was reported in all patients receiving VEN, and 95% of these patients also experienced grade 3/4 thrombocytopenia. There were three cases of tumor lysis syndrome. Conclusion: The addition of VEN to HMA has consistently shown benefit as first-line treatment and may have some benefit in R/R settings as well. Further studies are needed to compare across various lines of treatment and unfavorable disease. Dynamic strategies that improve toxicity management should be considered.

Acute GVHD, BK virus hemorrhagic cystitis and age are risk factors for transplant-associated thrombotic microangiopathy in adults.

Hematopoietic cell transplantation-associated thrombotic microangiopathy (TMA) is a complication associated with higher nonrelapse mortality (NRM) in patients who undergo allogeneic transplant (HCT). Current classification criteria are not generally agreed on or validated, and the presence of confounding factors after transplant contribute to underdiagnosis or delayed diagnosis of TMA. We studied risk factors, incidence, and biomarkers of TMA in 119 adult allogeneic HCT recipients. Twenty-seven patients developed a clinically actionable phenotype of TMA (CA-TMA) and the incidence of CA-TMA was 22% by day 180. Among the 27 patients who developed CA-TMA, 10 developed it before the onset of acute graft-versus-host disease (aGVHD), and 17 patients developed it after the onset of aGVHD. We report for the first time that age >50 years, BK hemorrhagic cystitis, and other viral infections (CMV, HHV-6, or adenovirus) are risk factors for adult CA-TMA. Even after adjustment for aGVHD, CA-TMA was independently associated with significantly higher NRM. These data illustrate relationships between CA-TMA and aGVHD, describe new risk factors for CA-TMA and emphasizes the need to develop validated set of criteria for timely diagnosis.

Letermovir Prophylaxis and Cytomegalovirus Reactivation in Adult Hematopoietic Cell Transplant Recipients with and without Acute Graft Versus Host Disease.

Cytomegalovirus (CMV) is the most clinically significant infection after allogeneic hematopoietic-cell transplantation (allo-HCT) and is associated with increased mortality. The risk for CMV reactivation increases with graft versus host disease (GVHD). GVHD contributes to significant morbidity and mortality and is treated with immunosuppressive therapies that can further increase CMV infection risk. Prophylaxis with letermovir, an oral antiviral approved to prevent CMV, has been shown to decrease the incidence of CMV infection post-allo-HCT in patients at high risk of CMV reactivation, but there is a lack of data confirming this benefit in patients with GVHD. In this single-center, retrospective study, we assessed the incidence of clinically significant CMV infection (CS-CMVi) in allo-HCT patients who received letermovir prophylaxis (n = 119) and who developed aGVHD compared to a control group (n = 143) who did not receive letermovir. Among aGVHD patients, letermovir prophylaxis decreased CS-CMVi in patients with aGVHD (HR 0.08 [95% CI 0.03-0.27], p < 0.001), reduced non-relapsed mortality (p = 0.04) and improved overall survival (p = 0.04). This data suggests that letermovir prophylaxis improves outcomes by preventing CS-CMVi in patients with aGVHD.

Effect of Early Post-Transplantation Tacrolimus Concentration on the Risk of Acute Graft-Versus-Host Disease in Allogenic Stem Cell Transplantation.

Acute graft versus host disease (aGVHD) remains a leading cause of morbidity and mortality in allogeneic hematopoietic stem cell transplant (allo-HSCT). Tacrolimus (TAC), a calcineurin inhibitor that prevents T-cell activation, is commonly used as a GVHD prophylaxis. However, there is variability in the serum concentrations of TAC, and little is known on the impact of early TAC levels on aGVHD. We retrospectively analyzed 673 consecutive patients undergoing allo-HSCT at the Ohio State University between 2002 and 2016. Week 1 TAC was associated with a lower risk of aGVHD II-IV at TAC level ≥10.15 ng/mL (p = 0.03) compared to the lowest quartile. The cumulative incidence of relapse at 1, 3 and 5 years was 33%, 38% and 41%, respectively. TAC levels at week 2, ≥11.55 ng/mL, were associated with an increased risk of relapse (p = 0.01) compared to the lowest quartile. Subset analysis with acute myeloid leukemia and myelodysplastic syndrome patients showed significantly reduced aGVHD with TAC level ≥10.15 ng/mL at week 1 and a higher risk of relapse associated with week 2 TAC level ≥11.55 ng/mL (p = 0.02). Hence, achieving ≥10 ng/mL during the first week of HCT may mitigate the risk of aGVHD. However, levels (>11 ng/mL) beyond the first week may be associated with suppressed graft versus tumor effect and higher relapse.

Safety of Axicabtagene Ciloleucel for the Treatment of Relapsed or Refractory Large B-Cell Lymphoma.

BACKGROUND: Diffuse large B-cell lymphoma is the most common type of non-Hodgkin lymphoma. Recent advances in immunotherapy have resulted in the development of chimeric antigen receptor-modified T-cell (CAR-T) therapy, such as axicabtagene ciloleucel (axi-cel). However, axi-cel administration is not without risks of toxicity. PATIENTS AND METHODS: This retrospective study of 37 patients with relapsed or refractory diffuse large B-cell lymphoma evaluated the incidence and severity of common and severe safety events after axi-cel treatment in a real-world setting. Ninety percent of patients had received 3 or more prior lines of therapy (median prior therapies 3, range 2-7) before receiving CAR-T therapy, and 32.4% had relapsed after prior stem-cell transplantation. RESULTS: All but one patient experienced cytokine release syndrome (CRS) of any grade (97.3%). Of those 36 patients, 83.3% experienced maximum CRS grade of 1 or 2, occurring after a median of 27 hours and persisting for a median of 6 days. Twenty-seven patients (73.0%) experienced neurotoxicity of any grade. Of those 27 patients, 96.3% experienced maximum neurotoxicity grade of 2 or higher, occurring after a median of 145 hours (6 days) and persisting for a median of 7 days. All 10 patients aged 65 or older had neurotoxicity of grade 2 or higher, compared to 59.3% (11/27) under age 65 (P = .02). Patients with baseline Eastern Cooperative Oncology Group performance status score of 2 were significantly more likely to have shorter time to neurotoxicity compared to patients with performance status of 0 (P = .01). CONCLUSION: With more real-life experience and data, we will be able to define and refine management of toxicities unique to CAR-T therapy.

Comparison of fixed dose reduced-intensity conditioning with fludarabine and busulfan to PK-guided busulfan AUC (FluBu4K) in hematopoietic stem cell transplant for AML/MDS.

A retrospective cohort study was conducted to assess differences in efficacy and tolerability between a busulfan AUC target of 16.4 mg × Hr/L per day (FluBu4K) and a conventional RIC regimen (FluBu2). Adult patients with a diagnosis of AML or MDS who received fludarabine + busulfan conditioning with or without antithymocyte globulin between 2015 and 2018 were included. The primary outcome was relapse free survival. Overall, 74 patients received conditioning with either FluBu4K or FluBu2. At 18 months, relapse-free survival was not significantly different, at 63.9% with FluBu4k compared to 57.5% with FluBu2 (p = 0.49). There was a statistically significant difference in the cumulative incidence of relapse at 18 months in favor of the FluBu4K regimen, at 12.0% vs 32.5% (p = 0.047). The results of this study indicate that for select patients, there may be benefit in choosing targeted FluBu4K over FluBu2. Adverse effects other than mucositis were not significantly different.

Tocilizumab as first-line therapy for steroid-refractory acute graft-versus-host-disease: analysis of a single-center experience.

Acute graft-versus-host-disease (aGVHD) is a complication after allogeneic stem cell transplant. After the failure of treatment with high dose corticosteroids, steroid-refractory aGVHD (SR aGVHD) is associated with high rates of mortality. Tocilizumab has evidence of activity in SR aGVHD. For patients ineligible for trials, the OSU James Comprehensive Cancer Center has been utilizing tocilizumab as first-line therapy for SR aGVHD. We retrospectively report on 15 patients who received tocilizumab. aGVHD grading and responses were based on consensus criteria. Median age at transplant was 49 years. Median time to tocilizumab administration was 9 days (range, 3-16). Six patients had complete responses (40%) with a resolution of aGVHD. From the last contact, median overall survival for responders was not yet reached vs. 31 days for non-responders (p = .0002). Patients with skin and/or GI aGVHD demonstrated the greatest benefit. Patients with liver aGVHD did not respond. Future studies are needed to evaluate tocilizumab prior to steroid failure.