Impact of inotuzumab ozogamicin on outcome in relapsed or refractory acute B-cell lymphoblastic leukemia patients prior to allogeneic hematopoietic stem cell transplantation and risk of sinusoidal obstruction syndrome/venous occlusive disease.

We evaluated 58 patients with relapsed or refractory (r/r) acute B-lymphoblastic leukemia (B-ALL; median age, 42.5 years; range, 16-69 years), treated with inotuzumab ozogamicin (INO) between 2016-2022 and who received an allogeneic hematopoietic stem cell transplantation (allo-HCT) consecutively. Forty-seven (81%) of the 58 patients were heavily pretreated receiving intensive chemotherapy +/- TKI, blinatumomab in 24 (41%) and allo-HCT at first-line in 11 (19%) patients. Complete remission (CR) rate prior to allo-HCT was 84%. Median follow-up was 30.5 months and median overall survival (OS) measured from start of INO was 11.2 months. Oneand 2-years OS rates were 50% (95%-CI, 38.4-56.1%) and 36.7% (95%-CI, 25.5-52.9%), respectively. Sinusoidal obstruction syndrome/venous occlusive disease (SOS/VOD) after allo-HCT occurred in 17 (29%) patients. Of those, 9 (53%) patients died due to SOS/VOD and multi-organ failure. Two had received >2 INO cycles (3 cycles, 5 cycles, n=1, each), all others ≤2 INO cycles prior to allo-HCT. Logistic regression analysis revealed conditioning with double alkylators (P=0.038) and allo-HCT during first-line therapy (P=0.050) as significant risk factors for SOS/VOD and in trend allo-HCT ≤ 60 days from last INO application (P=0.07), whereas number of INO cycles before allo-HCT and time between last INO application and allo-HCT were not significant. Relapse/progressive disease occurred in 20 (34%) patients. Of those, five (25%) patients are still alive, whereas 15 succumbed of their disease. Treatment with INO seems to be an effective approach with successful bridge-to-transplant. However, risk of SOS/VOD is high, necessitating continuous monitoring and recognition of SOS/VOD risk factors.

The baseline comorbidity burden affects survival in elderly patients with acute myeloid leukemia receiving hypomethylating agents: Results from a multicentric clinical study.

BACKGROUND: In older patients with acute myeloid leukemia (AML), the definition of fitness, prognosis, and risk of death represents an open question. METHODS: In the present study, we tested the impact on survival of disease- and patient-related parameters in a large cohort of elderly AML patients homogeneously assigned to treatment with hypomethylating agents (HMAs). RESULTS: In 131 patients with a median age of 76 years, we confirmed that early response (<0.001) and biology-based risk classification (p = 0.003) can select patients with better-predicted survival. However, a full disease-oriented model had limitations in stratifying our patients, prompting us to investigate the impact of baseline comorbidities on overall survival basing on a comorbidity score. The albumin level (p = 0.001) and the presence of lung disease (p = 0.013) had a single-variable impact on prognosis. The baseline comorbidity burden was a powerful predictor of patients' frailty, correlating with increased incidence of adverse events, especially infections, and predicted overall survival (p < 0.001). CONCLUSION: The comorbidity burden may contribute to impact prognosis in addition to disease biology. While the therapeutic armamentarium of elderly AML is improving, a comprehensive approach that combines AML biology with tailored interventions to patients' frailty is likely to fully exploit the anti-leukemia potential of novel drugs.

Long-Term Follow-Up of Elderly Patients with Acute Myeloid Leukemia Treated with Decitabine: A Real-World Study of the Apulian Hematological Network.

Decitabine, a DNA hypomethylating agent, was approved for use in adults with acute myeloid leukemia (AML) not eligible for standard chemotherapy and is now widely accepted as standard treatment. Although a number of clinical trials demonstrated its benefits in elderly AML patients, older adults and patients with frequent comorbidities are typically under-represented in such settings. Thus, the aim of the present study is to evaluate, in a real-world setting, the effectiveness and toxicity of decitabine administered as a single agent in unselected previously untreated elderly AML patients not eligible for intensive chemotherapy. In nine hematological departments of the Apulian Hematological Network (REP), we enrolled 199 patients (median age: 75.4 years; range: 61-91) with de novo (n = 94) or secondary/therapy-related (n = 105) AML treated with decitabine 20 mg/m2 for five days every 4 weeks. Hazard ratios (HR) and their 95% confidence intervals (CI) were estimated using multivariate Cox regression. The average number of cycles administered per patient was 6.3 (SD: 6.0; median: 5 cycles). Complete response was achieved by 31 patients (15.6%) and partial response by 57 (28.6%), for a total of 88 responders overall (44.2%). After a median follow-up of 33.6 months, median OS was 8.7 months (95% CI: 7.4-10.3), and the 6-month, 1-year, and 3-year OS rates were 62.7%, 37.0%, and 7.1%, respectively. Mortality was increased in AML patients with ≥3 comorbidities (HR = 2.45; 95% CI: 1.18-5.08) vs. no comorbidities and in those with adverse karyotype (HR = 1.58; 95% CI: 1.05-2.38) vs. favourable or intermediate profile. Infection was the main registered adverse event (46.0%). In conclusion, this REP real-life study demonstrates, after a follow-up of almost 3 years, how decitabine administered to AML patients not suitable for intensive chemotherapy is effective and well tolerated, even in a population of truly elderly patients with frequent comorbidities.

Inotuzumab ozogamicin is effective in relapsed/refractory extramedullary B acute lymphoblastic leukemia.

BACKGROUND: Extramedullary involvement of B-cell Acute Lymphoblastic Leukemia (EM-ALL) is a rare occurrence, characterized by dismal outcome and the absence of a defined and shared therapeutic approach. In the landscape of innovative compounds, inotuzumab ozogamicin (IO) is a promising drug, whose mechanism of action relies on the killing of CD22 positive leukemic cells, through the delivery, after cell binding, of a molecule of calicheamicin. CASE PRESENTATION: We report two cases of CD22 positive relapsed EM-ALL treated with IO, obtained as compassionate use. Case 1, a 66 years old woman, affected by Philadelphia (Ph) negative B-ALL, relapsed with extramedullary involvement after 6 standard chemotherapy courses, who reached a complete metabolic response with IO treatment. Case 2, a 67 years old man with Ph positive B-ALL, initially treated with ponatinib, a third generation tyrosine-kinase inhibitor (TKI), obtaining a prolonged deep molecular remission. Nevertheless, for skin relapse during TKI treatment, the patient received local radiotherapy and, shortly after, standard chemotherapy, as multiple abdominal sites of relapse were detected too, with no response. The patient then received IO, obtained as compassionate use, with a good metabolic response. CONCLUSIONS: These two cases suggest a possible key role of IO in the setting of advanced CD22 positive ALL, and underline its potential activity also in patients with EM involvement, relapsed after or refractory to conventional chemotherapy. Despite the well known hepatotoxic effect of the compound (Sinusoid Occlusive Syndrome), neither of them had such adverse event, moreover the second patient safely underwent allogeneic bone marrow transplantation.