Hepatotoxicity as dose-limiting toxicity of the combination of bosutinib and atezolizumab in patients with chronic myeloid leukemia. Results of the ZEROLMC study.

In the field of chronic myeloid leukemia (CML), new strategies are needed to increase the rate of successful treatment discontinuations, a crucial goal in this disease. Anti-PD-L1 checkpoint inhibitors are a promising therapeutic approach in CML after the demonstration of an increase of these inhibitory molecules in patients with CML. A phase Ib/II (NCT04793399, registration date March 11, 2021) open-label exploratory trial has been conducted to evaluate the safety of atezolizumab, a humanized anti-PD-L1 antibody, in combination with bosutinib in patients with newly diagnosed chronic phase CML. A total of 36 patients were planned to be enrolled, but the study had to be prematurely terminated due to safety concerns. Nine patients were included in the study, and only 8 went on to receive the combination with atezolizumab. There were a total of 44 adverse events (AEs) during the study period. The most frequent were gastrointestinal (50%), mostly mild (86% grade 1-2). The most serious AEs were hepatic. There were 17 hepatic AEs in 5 patients. Of the hepatic AEs 5 were during the bosutinib monotherapy phase and 12 during the combination phase (AST increase x4, ALT increase x4, blood bilirubin increase x1, alkaline phosphatase elevation x2, GGT increase x2), most of them grade 3-4. There were 2 patients who presented a dose-limiting toxicity; a grade 3 elevation of transaminases, that led to premature termination of the study. The combination of atezolizumab with bosutinib presents hepatotoxicity as a dose-limiting effect and therefore we do not recommend to explore this combination in future studies.

Obinutuzumab plus bendamustine for relapsed/refractory chronic lymphocytic leukemia and predictive and prognostic impact of genetic alterations: the phase II GABRIELL study.

GABRIELL was a phase II single-arm study to evaluate the efficacy and safety of obinutuzumab plus bendamustine for relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL). Seventy-two patients with active disease received treatment for up to six 28-day cycles. Overall response rate was 78.6% with a median progression-free survival (PFS) of 26 months, and overall survival (OS) not reached at the end of follow-up (36 months). Undetectable measurable residual disease (≤0.01%; 36.4% in bone marrow and 53.4% in peripheral blood) correlated with a significantly longer PFS and OS (vs. >0.01). Common grade ≥3 adverse events (76.4%) were neutropenia (58.3%), thrombocytopenia (26.4%) and febrile neutropenia (11.1%). TP53 disruption was the only independent predictive factor for response (Hazard ratio; HR: 0.228). Unmutated immunoglobulin heavy chain variable region (HR: 16.061) was a negative prognostic factor for PFS. In conclusion, the combination of obinutuzumab plus bendamustine is an active and generally adequately-tolerated treatment for R/R CLL.

Geriatric assessment in hematology scale predicts treatment tolerability in older patients diagnosed with hematological malignancies: The RETROGAH study.

INTRODUCTION: The GAH (Geriatric Assessment in Hematology) scale is a psychometrically valid tool aimed at identifying older patients with hematological malignancies at higher risk of treatment-related toxicity. Our objective in this study was to determine the weights for each dimension of the GAH scale and the cut-off point to reliably predict treatment tolerability in this population, estimated by a weighted receiver operating characteristic (ROC) analysis and quantified by the area under the curve (AUC). MATERIAL AND METHODS: The RETROGAH was a retrospective cohort study including 126 patients who had previously participated in the GAH study. Patients were ≥ 65 years old with newly diagnosed myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML), multiple myeloma (MM), or chronic lymphoid leukemia (CLL) and treated with standard front-line therapy within three months after having completed the GAH scale. RESULTS: The optimal cut-off value of the GAH total score to discriminate patients at higher risk of treatment toxicity was 42, with 68.5% sensitivity and 55.8% specificity. Using this value, 66.1% of patients evaluated were found to develop some type of toxicity. The AUC was 0.6259 (95% CI: 0.512-0.739; p = 0.035). DISCUSSION: The GAH scale not only would enable clinicians to individualize therapy based on individual risk of toxicity but also discriminate patients that will benefit most from intensive treatments from those requiring an adapted approach. While futures studies in clinical practice may improve the model and overcome its limitations, the GAH scale should not be used alone when making treatment decisions.

Safety and efficacy of bosutinib in fourth-line therapy of chronic myeloid leukemia patients.

Bosutinib is a second-generation tyrosine kinase inhibitor (2GTKI) approved at 400 mg once daily (QD) as first-line therapy in patients with chronic myeloid leukemia (CML) patients and at 500 mg QD in patients who are resistant to or intolerant of prior therapy. In clinical practice, bosutinib is often given to patients who have failed imatinib, nilotinib, and dasatinib (i.e., as fourth-line treatment), despite the limited data on its clinical benefit in this setting. We have retrospectively evaluated the results of bosutinib in a series of 62 CML patients who have failed to prior treatment with all three, imatinib, nilotinib, and dasatinib. Median time on TKI treatment before bosutinib start was 105 (9-163) months, and median duration on bosutinib was 9 months (1-30). Overall, probabilities to achieve complete cytogenetic response (CCyR) and major molecular response (MMR) were 25% and 24% respectively. After a median follow-up period of 14 months, the event-free survival and progression-free survival were 68 and 85%, respectively. Sixty-four percent of patients in CCyR at the time of bosutinib start were able to achieve MMR. In contrast, patients without CCyR, probabilities to obtain CCyR and MMR were 25% and 14%. Bosutinib was well tolerated in this heavily pretreated patients' cohort. Pleural effusions and diarrhea were the most frequent grade II-IV side effects, leading to treatment discontinuation in 16% of patients. Bosutinib is an effective treatment option for patients who have failed previous 2GTKIs due to intolerance. However, efficacy seems to be related to the molecular response that the patient achieved prior to bosutinib.

Serum ferritin as prognostic marker in classical Hodgkin lymphoma treated with ABVD-based therapy.

Ferritin levels might correlate with disease activity in classical Hodgkin lymphoma (cHL). We analyzed the prognostic significance of the ferritin value at diagnosis in 173 cHL patients treated with ABVD between 2003 and 2013. The 5-year overall survival (OS) and progression-free survival (PFS) probabilities were 80% and 64%, respectively. Patients with ferritin ≥ 350 µg/l [high ferritin group (HF), n = 62] were more likely to have advanced stage disease, B-symptoms and higher International Prognostic Score (IPS) compared with patients with ferritin < 350 µg/l [low ferritin group (LF), n = 111]. The complete remission (CR) rate and 5-year PFS and OS probabilities were lower in HF vs. LF patients (69% vs. 89%, p = 0.025; 40% vs. 78%, p < 0.001; 61% vs. 90%, p = 0.001; respectively). Multivariate analysis revealed that advanced stage (p = 0.001) and ferritin levels ≥ 350 µg/l (p = 0.002) were independent predictors for PFS. In conclusion, the ferritin level at diagnosis is a useful prognostic marker for cHL.