Shorter duration of venetoclax administration to 14 days has same efficacy and better safety profile in treatment of acute myeloid leukemia

How to improve AML outcomes?

Understanding the intricacies of the pathophysiology and genomic landscape has enhanced the long-term outcomes for patients with acute myeloid leukemia (AML). The identification of novel molecular targets has introduced new therapeutic strategies that attempt to surpass the dominance of the "7 + 3 regimen" established in the 1970s. In 2022, the World Health Organization and International Consensus Classification revised their definitions and approaches to AML, reflecting the current and evolving changes at the molecular level. The guidelines are now grounded in a definition of the disease that emphasizes genetic characteristics. Today, we recognize AML as a genetically diverse disease; a retrospective study identified 5234 driver mutations across 76 genes or genomic regions, with two or more drivers observed in 86% of patients (Papaemmanuil et al., N Engl J Med 374:2209-21, 2016).

Reduced duration and dosage of venetoclax is efficient in newly diagnosed patients with acute myeloid leukemia

OBJECTIVES

The combination of Venetoclax (VEN) and Azacitidine (AZA) increases survival outcomes and yields excellent responses in patients with acute myeloid leukemia (AML). However, dose reduction (or discontinuation) is commonly encountered due to therapy-related toxicity. Thus, this study aimed to investigate the efficiency and safety of a lower dosage of venetoclax for the treatment of AML.

METHODS

This observational study analyzed the characteristics and outcomes of newly diagnosed AML patients who received 100 mg VEN combined with AZA for 14 days at our institution.

RESULTS

A total of 36 patients were enrolled, and the median age at diagnosis was 64 years. After a median follow-up of 15 (range 4-29) months, the median overall survival (OS) and progression-free survival (PFS) for the whole cohort were 17 (4-29) months and 12 (1-28) months, respectively. Meanwhile, the overall response rate (ORR) was 69.4%, and the CRc rate was 66.7% in the whole cohort. Subgroup analysis revealed that NPM1 mutations and FAB-M5 subtype were associated with higher response rates, whereas the adverse ELN risk group was predictive of an inferior response. Moreover, ASXL1, NPM1, and IDH1/2 mutations negatively impacted PFS.

DISCUSSION

Our study optimized the administration of venetoclax plus azacytidine for the treatment of AML patients. Response rates were favorable, with median survival in agreement with the findings of earlier reports, offering valuable insights for optimizing VEN-based regimens.

CONCLUSION

In summary, the VEN combination regimen is effective for the treatment of newly diagnosed AML patients in the real world despite VEN dose reductions .

Ven the dose matters: Venetoclax dosing in the frontline treatment of AML

Older/unfit adults with AML have worse outcomes and fewer treatment options than their younger/fit counterparts. In vitro studies have found a synergistic effect of hypomethylating agents (HMA) with venetoclax (VEN) on AML cells and since the phase 3 VIALE-A trial demonstrated a survival benefit, HMA + VEN has become the standard of care in the frontline setting for older/unfit adults with AML. Unfortunately, the standard 28-day cycle of VEN is associated with a high degree of myelosuppression leading to treatment delays and dose modifications. Many small retrospective studies have successfully shown comparable outcomes to VIALE-A with reduced dose/duration of VEN. Furthermore, low dose metronomic dosing of HMA + VEN has shown clinical benefit while minimizing myelotoxicity. Future trials are vital to understand the appropriate dose of VEN in combination with HMA, to evaluate HMA + VEN compared to intensive therapy for younger/fit patients, and to explore its utility in the relapsed/refractory setting.

Azacitidine in combination with shortened venetoclax treatment cycles in patients with acute myeloid leukemia

The combination of venetoclax with hypomethylating agents is currently the standard of care for elderly patients with acute myeloid leukemia (AML) ineligible for intensive chemotherapy. Despite its favorable efficacy, clinical use is often associated with post-remission cytopenia, frequently necessitating treatment delays and dose modifications. This study aims to evaluate the efficacy and safety of shortened venetoclax treatment durations. A multicenter analysis was conducted involving 20 adult AML patients receiving venetoclax (7 or 14 days with 9 and 11 patients, respectively) combined with 5-azacitidine (5-7 days) between 2021 and 2024. The cohort included patients from four German academic centers all treated in first line. Outcome measures included bone marrow response, transfusion dependence, overall survival (OS) and progression-free survival (PFS). Median age was 73.5 years, with 70% of patients having secondary AML. Adverse molecular risk was observed in 75% of patients. The overall response rate (ORR) was 100%, with a composite complete remission rate of 78%. No significant differences in response rates were observed between the 7-day and 14-day venetoclax regimens. Median OS for the cohort was 15 months. Infection-related complications were observed in 55% of patients, with severe sepsis in 20% of cases. In this cohort, shortened venetoclax regimens demonstrated efficacy comparable to standard treatment protocols, with a potential reduction in hematologic toxicity. These findings support the individualization of treatment regimens to optimize clinical outcomes while potentially minimizing adverse effects.

HMA/VEN treatment modifications and associated outcomes in IDH-mutant AML

Hypomethylating agents (HMA) and venetoclax (VEN) are commonly used in patients with IDH-mutated (IDHm) acute myeloid leukemia (AML) ineligible for induction chemotherapy. While prior studies demonstrated high response and survival rates with HMA/VEN in IDHm AML, the impact of treatment modifications in real-world settings is unclear. We retrospectively reviewed 89 IDHm AML patients treated with HMA/VEN from January 2018 to June 2023. CR/CRi rates were 76% in newly diagnosed (ND) and 55% in relapsed/refractory (R/R) patients, and median overall survival was 29.2 months (ND) and 17.1 months (R/R), respectively. Treatment modifications were common. Early VEN reductions were associated with lower response rates but not worse survival. Prolonged cycles were not associated with worse response rates or survival. Significant neutropenia and ED visits or unplanned hospitalizations were considerable before and after CR/CRi, though febrile neutropenia decreased afterward. HMA/VEN is efficacious, with treatment modifications not affecting survival, though long-term toxicities are notable.

Current status and research directions in acute myeloid leukemia

The understanding of the molecular pathobiology of acute myeloid leukemia (AML) has spurred the identification of therapeutic targets and the development of corresponding novel targeted therapies. Since 2017, twelve agents have been approved for the treatment of AML subsets: the BCL2 inhibitor venetoclax; the CD33 antibody drug conjugate gemtuzumab ozogamicin; three FLT3 inhibitors (midostaurin, gilteritinib, quizartinib); three IDH inhibitors (ivosidenib and olutasidenib targeting IDH1 mutations; enasidenib targeting IDH2 mutations); two oral hypomethylating agents (oral poorly absorbable azacitidine; fully absorbable decitabine-cedazuridine [latter approved as an alternative to parenteral hypomethylating agents in myelodysplastic syndrome and chronic myelomonocytic leukemia but commonly used in AML]); and CPX-351 (encapsulated liposomal 5:1 molar ratio of cytarabine and daunorubicin), and glasdegib (hedgehog inhibitor). Other targeted therapies (menin inhibitors, CD123 antibody-drug conjugates) are showing promising results. To achieve optimal results in such a rare and heterogeneous entity as AML requires expertise, familiarity with this rare cancer, and the access to, and delivery of disparate therapies under rigorous supportive care conditions. In this review, we update the standard-of-care and investigational therapies and outline promising current and future research directions.

A systematic review of venetoclax for the treatment of unfit AML patients in real-world: is all that glitters gold?

Acute myeloid leukemia (AML) is an aggressive hematological disease that mainly affects elderly patients. Following the randomized VIALE-A trial, current standard treatment in patients who are not candidates for intensive chemotherapy consists of the combination of venetoclax (VEN), a selective inhibitor of the anti-apoptotic protein BCL-2, with azacitidine (AZA) or decitabine (DEC). We performed a systematic review to critically assess the growing existing evidence regarding the effectiveness of the VEN-based combinations in unfit adult patients with newly diagnosed AML in the real-world setting. Following PRISMA guidelines, a systematic search of published manuscripts and conference abstracts (European Hematology Association and American Society of Hematology) was conducted (updated March 2024). Primary outcomes were composite complete remission (CRc) and median overall survival (mOS). A total of 73 studies fulfilled inclusion criteria, with a median age of 73 years old. The weighted mean mOS was 10.3 months among 7 138 patients, significantly lower than expected according to the VIALE-A trial (14.7 months), while the weighted mean CRc rate was 58.2% among 5 831 patients, slightly lower to that reported in the VIALE-A (66.4%). Early death rates at 30 and 60 days were 5% and 13%, respectively. The weighted mean percentage of subsequent allogeneic transplant was 15.4%. In conclusion, breakthrough mOS reported in the VIALE-A trial using VEN-AZA was not well reproduced in real world for unfit newly diagnosed AML patients, while CRc rates were more consistent. Strategies to optimize patient selection, dosing regimens, and supportive care are crucial to improve outcomes in real-world.

Less is more: An analysis of venetoclax and hypomethylating agent post-induction treatment modifications in AML

Venetoclax (Ven) combined with a hypomethylating agent (HMA) enhances survival in elderly/unfit acute myeloid leukemia (AML) patients, yet often necessitates regimen modifications due to intolerance. However, it is unclear how these modifications affect patient outcome. This retrospective cohort study evaluates the impact of post-induction HMA/Ven regimen modifications on disease progression and survival. This study reviewed 142 AML patients treated with HMA/Ven within the Northwell Health System from January 2019 to December 2022. To assess the impact of post-induction regimen modifications, patients were grouped according to median days between cycles (≤34 or ≥35 days cycle intervals) and median Ven days per cycle (≤14 or ≥15 days/cycle) based on only cycle 3 and beyond. Kaplan-Meier and Cox proportional hazard regression analyses were employed for univariate and multivariate assessments, respectively. There was no significant difference in median progression-free survival (mPFS)(11.6 vs 11.8 months, p = 0.73) or median overall survival (mOS)(15.1 vs 21.8 months, p = 0.16) between cycle interval groups. However, there was a clinically and statistically significant advantage in mPFS (15.8 vs 8.7 months, p = 0.01) and mOS (24.7 vs 11.3 months, p = 0.006) for patients with a median of ≤14 Ven days/cycle compared to ≥15 Ven days/cycle. Multivariate analysis demonstrated that ≤14 days of Ven for cycle 3 and beyond was an independent predictor of decreased mortality (HR 0.18, CI 0.07-0.48, p = 0.0007). Extended cycle intervals did not adversely affect mortality while reduced Ven duration per cycle post-induction was associated with improved survival in elderly AML patients.

Venetoclax-Related Neutropenia in Leukemic Patients: A Comprehensive Review of the Underlying Causes, Risk Factors, and Management

Venetoclax is a Bcl-2 homology domain 3 (BH3) mimetic currently approved for the treatment of chronic lymphocytic leukemia (CLL) and acute myeloid leukemia (AML) that has proven to be highly effective in reinstating apoptosis in leukemic cells through the highly selective inhibition of the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2). Clinically, venetoclax has provided lasting remissions through the inhibition of CLL and AML blasts. However, this activity has often come at the cost of grade III/IV neutropenia due to hematopoietic cells' dependence on Bcl-2 for survival. As life-threatening infections are an important complication in these patients, an effective management of neutropenia is indispensable to maximize patient outcomes. While there is general consensus over dose reduction and scheduling modifications to minimize the risk of neutropenia, the impact of these modifications on survival is uncertain. Moreover, guidelines do not yet adequately account for patient-specific and disease-specific risk factors that may predict toxicity, or the role combination treatment plays in exacerbating neutropenia. The objective of this review is to discuss the venetoclax-induced mechanism of hematological toxicity, the potential predictive risk factors that affect patient vulnerability to neutropenia, and the current consensus on practices for management of neutropenia.

Venetoclax and hypomethylating agents in critically ill patients with newly diagnosed acute myeloid leukaemia

Venetoclax (VEN) in combination with hypomethylating agents (HMAs) is considered the standard of treatment for individuals with newly diagnosed acute myeloid leukaemia (AML) who are ineligible for intensive chemotherapy. We conducted a retrospective analysis that encompassed 16 critically ill patients newly diagnosed with AML who were admitted to the intensive care unit (ICU) and received the VEN and HMA regimen. Among them, 13 were primary AML, and three were MDS-transformed AML. The mean Acute Physiology and Chronic Health Evaluation II (APACHE II) score was 18.9, and the mean sepsis-related organ failure assessment score (SOFA) was 6.2. The average length of the ICU stay was 27.3 days. The median duration of VEN administration was 16 days. After the first course of VEN + HMA, 12 cases (75%) achieved complete remission (CR) or CR with incomplete haematological recovery (CRi). Among the five patients harbouring TP53 mutations, the overall response rate (ORR) was 90%. All patients experienced grade 3-4 haematological adverse events (AEs). With a median follow-up of 9.5 months (range: 0.5-23), the overall survival (OS) rate was 43.75%. TP53-wild patients and CR state after the first course of VEN-HMA indicated better survival. The combination of VEN and HMA has demonstrated a significantly elevated therapeutic response rate in newly diagnosed AML patients with critical illness.

Advancements and Challenges in the Treatment of AML

The therapeutic arsenal for the management of AML has expanded significantly in recent years. Before 2017, newly diagnosed AML was treated with either standard cytarabine- and anthracycline-based induction chemotherapy (for all fit patients) or a single-agent hypomethylating agent (in unfit patients or those 75 years and older). While assessing patient fitness remains important, characterizing the disease biology has become critical to select the optimal initial therapy for each patient with more options available. FLT3 inhibitors, gemtuzumab ozogamicin, and CPX-351 have been shown to improve outcomes for specific subsets of patients. Venetoclax (VEN) with a hypomethylating agent (HMA) is the standard-of-care frontline regimen for most older patients, except perhaps for those with an IDH1 mutation where ivosidenib with azacitidine may also be considered. On the basis of the success seen with HMA/VEN in older patients, there is now increasing interest in incorporating VEN into frontline regimens in younger patients, with promising data from multiple early phase studies. This article focuses on recent updates and ongoing challenges in the management of AML, with a particular focus on the ongoing challenge of secondary AML and considerations regarding the selection of initial therapy in younger patients. An overview of common side effects and toxicities associated with targeted therapies is also presented here, along with recommended strategies to mitigate these risks.

Pharmacokinetic Consideration of Venetoclax in Acute Myeloid Leukemia Patients: A Potential Candidate for TDM? A Short Communication

BACKGROUND

Venetoclax (VNX)-based regimens have demonstrated significantly favorable outcomes in patients with acute myeloid leukemia (AML) and are now becoming the standard treatment. Tyrosine kinase inhibitors are administered at a fixed dose, irrespective of body surface area or weight. For such orally targeted therapies, real-world data have highlighted a larger pharmacokinetic (PK) interindividual variability (IIV) than expected. Even if VNX PKs have been well characterized and described in the literature, only 1 clinical trial-based PK study has been conducted in patients with AML. This study aimed to evaluate the PK of VNX in AML patients.

MATERIAL AND METHODS

We retrospectively analyzed all patients treated with a combination of VNX-azacitidine between January and July 2022 at our center, using at least 1 available VNX blood sample. Based on a previously published population PK model, individual PK parameters were estimated to evaluate the exposure and IIV.

RESULTS

and Discussion. Twenty patients received VNX in combination with azacitidine, according to the PK data. A total of 93 plasma concentrations were collected. The dose of VNX was 400 mg, except in 7 patients who received concomitant posaconazole (VNX 70 mg). The patients' weight ranged from 49 kg to 108 kg (mean = 78 kg). Mean individual clearance was 13.5 ± 9.4 L/h with mean individual daily area under the concentration-time curves of 35.8 mg.h/L with significant IIV (coefficient of variation = 41.1%). Ten patients were still alive (8 in complete response), but all experienced at least 1 hematological toxicity of grade ≥ 3.

CONCLUSIONS

Based on the observed large PK variability in the data from our real-world AML patients, the risk of drug interactions and the recommended fixed-dosage regimen of VNX therapeutic drug monitoring may be useful.

Venetoclax duration (14 vs. 21 vs. 28 days) in combination with hypomethylating agent in newly diagnosed acute myeloid leukemia: Comparative analysis of response, toxicity, and survival

Overall survival and response rates of 270 patients with newly diagnosed acute myeloid leukemia receiving venetoclax (Ven) plus hypomethylating agent, stratified by Ven dosing schedule (Cycle 1 Ven 14 vs. 21 vs. 28 days).

Venetoclax in adult acute myeloid leukemia

Venetoclax is a potent inhibitor that specifically targets B-cell lymphoma-2 (BCL-2), which has been demonstrated to be effective in preclinical studies utilizing acute myeloid leukemia (AML) cell lines and xenograft models. Significant antileukemic activity was also observed in clinical trials, both as a monotherapy and in combination with other drugs. This novel therapeutic approach has revolutionized the treatment prospects for AML patients with unfavorable prognoses and those who are unable to tolerate intensive chemotherapy. Nevertheless, further investigations are required to establish the optimal dosing, sequencing, and combinational strategies of venetoclax for AML treatments. Additionally, identifying biomarkers is crucial for predicting response and resistance to this targeted intervention. In this review, we provide an overview of venetoclax-based therapy for AML and explore potential avenues for future research.

Venetoclax with Hypomethylating Agents in Newly Diagnosed Acute Myeloid Leukemia: A Systematic Review and Meta-Analysis of Survival Data from Real-World Studies

In recent years, the association of venetoclax (VEN) with hypomethylating agents (HMAs) significantly improved the outcome of patients with newly diagnosed acute myeloid leukemia (AML) who were unfit for intensive chemotherapy and became the standard of care after the publication of the pivotal RCT VIALE-A. However, it is still not clear to what extent the results observed in the VIALE-A apply to a real-world setting. For this reason, we carried out a systematic review and meta-analysis of real-world studies on newly diagnosed patients with AML, ineligible for intensive induction chemotherapy, receiving first-line VEN+HMA. We then compared their results in term of survival with those from the VIALE-A. Kaplan-Meier curves were extracted from all included studies and individual survival data was reconstructed. We then estimated a pooled survival curve and compared it with the results of the VIALE-A using the log-rank test. We also conducted a secondary analysis including only studies considering VEN plus azacytidine (AZA) as treatment, as this was the schedule originally used in the VIALE-A. Nineteen real-world studies met the inclusion criteria and were included in the systematic review. Most of them reported a worse survival than the VIALE-A. The pooled survival curve was similar to that reported in the VIALE-A during the first three months of treatment but diverged thereafter (p-value = 0.0001). The pooled median survival among the real-world studies was 9.37 months (95%CI 8.81-10.5), substantially lower than that reported in the VIALE-A (14.7 months; 95%CI 11.9-18.7). Results slightly increased when the analysis was restricted to the studies using VEN+AZA as treatment (median survival: 11.5 months; 95%CI 10.2-14.8). Survival of newly diagnosed AML patients treated with VEN+HMAs in a real-world setting seems to be lower than previously reported in the VIALE-A, while the effect of VEN+AZA is more in line with expected results. Future studies are needed to evaluate whether this apparent discrepancy is due to the different characteristics of enrolled patients or to a non-optimal adherence to therapy, and whether alternative regimens can provide better results in terms of safety and effectiveness.

Venetoclax: A New Partner in the Novel Treatment Era for Acute Myeloid Leukemia and Myelodysplastic Syndrome

BACKGROUND

Acute Myeloid Leukemia (AML) and Myelodysplastic Syndrome (MDS) are two closely related blood cancers that are more frequent in older adults. AML is the most common type of adult acute leukemia, and MDS is characterized by ineffective blood cell production and abnormalities in the bone marrow and blood. Both can be resistant to treatment, often due to dysfunction in the process of apoptosis, the body's natural mechanism for cell death. Venetoclax, an orally-administered medication that selectively targets the BCL-2 protein, has shown promise in enhancing treatment sensitivity in some hematological malignancies by reducing the apoptotic threshold. This review aims to evaluate the effectiveness of venetoclax in treating AML and MDS, as well as potential mechanisms of resistance to the medication.

METHODS

A literature search was conducted utilizing PUBMED to capture all relevant research articles on the use of venetoclax as a therapy for both diseases. The MeSH terms "acute myeloid leukemia", "myelodysplastic syndrome" and "venetoclax" were searched. Furthermore, Clinicaltrials.gov was accessed to ensure the inclusion of all ongoing clinical trials.

RESULTS

Although Venetoclax showed modest results as a single-agent therapy in AML, venetoclax-based combination therapies? mainly with hypomethylating agents or low-dose cytarabine? yielded significantly positive results. Preliminary results oN the use of venetoclax-based combination therapy with HMA, mainly azacitidine, in unfit high-risk MDS also yielded optimistic results. Identification of mutations for which various drugs have been approved has spurred active investigation of venetoclax in combination trials.

CONCLUSION

Venetoclax-based combination therapies have been shown to induce rapid responses and increase overall survival in AML patients unfit for intensive chemotherapy. These therapies are also yielding positive preliminary results in high-risk MDS patients in phase I trials. Resistance to venetoclax and drug-related toxicity are two main obstacles that need to be overcome to reap the full benefits of this therapy.