Minimal Residual Disease Evaluation in Acute Myeloid Leukemia patients treated with Venetoclax and Hypomethylating Agents

Acute myeloid leukemia (AML) is a genetically heterogeneous malignant clonal disorder of the hematopoietic system. Treatment of older patients with AML is quite challenging, an older age is independently associated with an inferior outcome. Hypomethylating agents such as 5-azacytidine and decitabine, has shown to be a promising option for older patients with AML, who are not suitable candidates for intensive therapies. Venetoclax (VEN) is an oral, potent, and selective BCL2 inhibitor. Synergistic activity against myeloid malignancies is seen in vitro and in vivo with VEN in combination with lower intensity antileukemia therapy, such as low-dose cytarabine (LDAC) or hypomethylating agents (HMA). This project, aims to analyze the response of AML patients to Venetoclax and monitored by MRD assay (multiparameter flow cytometry or MFC) We will collect data on consecutive patients affected by de novo or secondary AML according to WHO 2016 criteria, in relapse or refractory phase of disease. Data will include clinical data and response data (minimal residual disease tested by multiparameter flow cytometry or MFC). The combined therapy of Venetoclax and HMA resulted in good responses, especially in chemo-refractory patients and allogeneic transplant candidates. The quality of the responses made it possible, in a good percentage, to achieve allogeneic transplantation in MRD-negativity conditions. The recurrence of treatment-associated neutropenia was the most frequent reason for temporary treatment discontinuation, consequently a document for the management of neutropenia was drawn up, derived from the various indications in the literature. Despite the good results achieved, resistance to venetoclax and the possibility of discontinuing treatment once deep and lasting complete remission has been achieved remain open questions

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 +/- tyrosine kinase inhibitor, blinatumomab in 24 (41%) and allo-HCT at first-line in 11 (19%) patients. Complete remission 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. One- and 2-year OS rates were 50% (95% confidence interval [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, nine (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

BCR-ABL1 transcript detection in patients with Philadelphia-positive Acute Lymphoblastic Leukemia (ALL) using a new and high sensitive nanofluidic method

Background: Detection of residual leukemic cells by measuring BCR-ABL1 transcript level with assays based on quantitative polymerase chain reaction (qPCR) is necessary in the monitoring of minimal residual disease in patients with BCR-ABL1 positive ALL. Aim: To investigate the efficacy of a high sensitive method based on nanofluidic platform (Fluidigm Corporation, South San Francisco, CA) to detect and quantify residual and rare BCR-ABL1 copies, we compared results obtained by conventional qPCR with those obtained by the nanofluidic approach. Patients and methods: We analyzed 60 BCR-ABL1 positive ALL samples expressing p190 (42) or p210 (18) isoform, first by TaqMan absolute qPCR (Applied Biosystems 7900HT Fast Real-Time PCR System). BCR-ABL1 target gene and ABL1 control gene copies were derived by the interpolation of cycle threshold values to the appropriate standard curve obtained using serial plasmid dilutions containing known BCR-ABL1 or ABL1 gene copies. Results: Samples resulted in complete (22) or major (38) molecular response (BCR-ABL1/ABL1 ratio 6a 0.001 or < 0.1, respectively; 3,8 BCR-ABL1 mean copy number copies). Subsequently we reanalyzed the samples using the 12.765 Digital array (Fluidigm) and the integrated BioMark Digital PCR Analysis software (Fluidigm). The nanofluidic biochip consists in twelve panels, each containing 765 individual reaction chambers where samples are portioned prior to qPCR. As fluorescent signal is produced only in chambers containing copies of the target sequence, digital array provides an absolute quantification by counting the number of positive reactions. Sensitivity and reproducibility of the assay were assessed using six serial dilutions of plasmids (Ipsogen) expressing known BCR-ABL1 p190 transcript copy number (10000; 1000; 100; 50; 10; 1 copies). A 2 \ub5l volume of input cDNA was loaded and two panel for each dilution were used. Results showed a detection rate until a copy of target sequence and a pairing significantly effective between replicates. We then analyzed duplicates of BCR-ABL1 ALL samples: digital array resulted positive in 21 of major molecular response samples (2,13 BCR-ABL1 mean copy number copies) and in any complete molecular response samples. In conclusion, the Fluidigm nanofluidic platform provides a high sensitive assay, able to detect until a single copy of BCR-ABL1 transcript, and it could provide an accurate monitoring method for BCR-ABL1-positive ALL CR patients. Supported by European LeukemiaNet, AIL, AIRC, FIRB 2006, PRIN 2008, Ateneo RFO grants, Project of integreted program (PIO), Programma di Ricerca Regione \u2013 Universit\ue0 2007 \u2013 2009

Nelarabine is safe and effective in adult relapsed or refractory T cellacute lymphoblastic leukemia (T-ALL) and lymphoblastic lymphoma (T-LBL): The Bologna experience

Background. Nelarabine (N) is approved for the treatment of T-ALL and T-LBL that have not responded to or has relapsed after treatment with at least 2 chemotherapy regimens. Aim. To evaluate safety profile and efficacy of N as savage therapy in 16 adult relapsed or refractory T-ALL or T-LBL. Methods. After obtaining an informed consent, 16 patients (median age 33 years, range 19-45, M/F = 13/3) affected by T-ALL (n=10) and T-LBL (n=6) received savage therapy with N (median cycle=1, range 1-3), administered at standard adult dosage (1500 mg/sqm on days 1, 3 and 5, every 21). Four patients were primary resistant to induction treatment, 7 patients were relapsed after two previous chemotherapy regimens (including allogeneic BMT in 4 cases and autologous SCT in 1 case); the remaining 6 patients had a molecular relapsed disease (MRD positive). Molecular characterization was performed, including NOTCH and WT-1 genes mutational status. GEP analysis, according to Ferrando A. stratification (Cancer Cell 2002), is still ongoing. Results. Currently, 12 out of 16 patients are evaluable, due to a too short follow up in the other 4 cases. Seven out of 12 patients obtained a complete remission (CR) (5 T-ALL 2 T-LBL);a partial remission (PR) was documented in 2 cases, with an overall response rate (ORR) of 75%. Median duration of CR was 10 weeks (range 2.8-54+). Among these, 2 out of 4 patients in molecular relapse reached a molecular CR and underwent an allogenic BMT (currently in CR after a median follow up of 12 months). Extra- hematological toxicity, not clearly related to the drug, occurred in 3 cases, determining, a complete and irreversible paraplegia, a condition of mental confusion, and a peripheral neuropathy, respectively. Conclusions. N showed a strong efficacy also in cases with low levels of residual disease, in addition to a good safety profile. Neurological toxicity needs to be strictly monitored. Acknowledgments. European LeukemiaNet, AIL, AIRC, Fondazione Del Monte di Bologna e Ravenna, FIRB 2006, PRIN 2008, Ateneo RFO grants, Project of integrated program (PIO), Programma di Ricerca Regione \u2013 Universit\ue0 2007 \u2013 2009