COVID-19 Vaccination Response and Its Practical Application in Patients With Chronic Lymphocytic Leukemia.

Patients with chronic lymphocyticleukemia (CLL) typically have innate/adaptive immune system dysregulation, thus the protective effect of coronavirus disease 2019 (COVID-19) vaccination remains uncertain. This prospective review evaluates vaccination response in these patients, including seropositivity rates by CLL treatment status, type of treatment received, and timing of vaccination. Antibody persistence, predictors of poor vaccine response, and severity of COVID-19 infection in vaccinated patients were also analyzed. Practical advice on the clinical management of patients with CLL is provided. Articles reporting COVID-19 vaccination in patients with CLL, published January 1, 2021-May 1, 2022, were included. Patients with CLL displayed the lowest vaccination responses among hematologic malignancies; however, seropositivity increased with each vaccination. One of the most commonly reported independent risk factors for poor vaccine response was active CLL treatment; others included hypogammaglobulinemia and age >65-70 years. Patients who were treatment-naive, off therapy, in remission, or who had a prior COVID-19 infection displayed the greatest responses. Further data are needed on breakthrough infection rates and a heterologous booster approach in patients with hematologic malignancies. Although vaccine response was poor for patients on active therapy regardless of treatment type, CLL management in the context of COVID-19 should aim to avoid delays in antileukemic treatment, especially with the advent of numerous strategies to mitigate risk of severe COVID-19 such as pre-exposure prophylaxis, and highly effective antivirals and monoclonal antibody therapy upon confirmed infection. Patients with CLL should remain vigilant in retaining standard prevention measures such as masks, social distancing, and hand hygiene.

Utility of measurable residual disease for predicting treatment outcomes with BCR- and BCL2-Targeted therapies in patients with CLL.

Inhibitors targeting B-cell receptor (BCR) signaling pathway proteins and B-cell lymphoma-2 (BCL2) in chronic lymphocytic leukemia (CLL) are recommended in the first-line and relapsed/refractory disease settings. Measurable residual disease (MRD) is an important prognostic tool in patients treated with the BCL2-targeted agent, venetoclax. We explored the relationship between MRD status and progression-free (PFS)/overall survival (OS) in patients with CLL, following treatment with novel BCR- and BCL2-targeted agents. Compared with chemoimmunotherapy, higher rates of undetectable (u)MRD were achieved with BCL2-targeted therapies; achieving uMRD status was associated with longer PFS and OS than MRD-positivity. Continuous treatment with BCR-targeted agents did not achieve uMRD status in many patients, and outcomes were not correlated with uMRD status. Future clinical trials of targeted treatment combinations could be designed to demonstrate uMRD as a treatment objective, and allow a response-driven, personalized strategy to optimize treatment and improve OS outcomes.

A review of the incidence of tumor lysis syndrome in patients with chronic lymphocytic leukemia treated with venetoclax and debulking strategies.

We reviewed the literature (January 2010-June 2021) on the effectiveness of debulking strategies before venetoclax initiation in patients with chronic lymphocytic leukemia to reduce tumor burden, downgrade tumor lysis syndrome (TLS) risk, and avoid hospitalization. Low TLS incidence and reduced TLS risk based on tumor burden were reported following debulking in clinical trials. Real-world observational studies reporting debulking regimens recorded no TLS events, and those without debulking strategies had greater TLS incidence. Debulking prior to venetoclax considerably reduces TLS incidence. Further clinical trials and real-world studies may provide additional evidence on effectiveness of debulking in reducing TLS incidence and hospitalization need.

The impact of early discontinuation/dose modification of venetoclax on outcomes in patients with relapsed/refractory chronic lymphocytic leukemia: post-hoc analyses from the phase III MURANO study.

Fixed-duration venetoclax plus rituximab (VenR) has a manageable safety profile and improves survival in patients with relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL). We present data from the phase III MURANO study on the impact of venetoclax modification or premature discontinuation on outcomes in patients with R/R CLL. Time-dependent Cox proportional hazards regression models, stratified by 17p deletion and risk status, evaluated the impact of venetoclax discontinuation/modification on investigator-assessed progression-free survival (PFS) and overall survival (OS). Analyses were performed retrospectively (without type-1 error control) in intention-to-treat patients from the VenR arm of MURANO. Overall, 140/194 (72%) patients in the VenR arm completed 2 years of therapy; 54/194 (28%) patients prematurely discontinued treatment. Inferior PFS was observed in patients prematurely discontinuing venetoclax for any reason (disease progression excluded; p.