Outcomes of allogeneic hematopoietic cell transplantation under letermovir prophylaxis for cytomegalovirus infection

Risk-Adapted Letermovir Prophylaxis Based on a Scoring System Predicting a Higher Burden of Cytomegalovirus Exposure After Allogeneic Hematopoietic Cell Transplantation

We previously reported that the area under the curve of log-transformed cytomegalovirus antigenemia (CMV-AUC) until 100 days after allogeneic hematopoietic cell transplantation (allo-HCT) was associated with an increased risk of non-relapse mortality. We applied a risk-adapted letermovir (LTV) prophylaxis strategy guided by a risk score that predicts a higher CMV-AUC. First, we retrospectively analyzed 278 allo-HCT recipients between 2007 and 2017 (Period 1). We scored risk factors for higher CMV-AUC by odds ratios: malignant lymphoma including adult T cell leukemia/lymphoma (1 point), an unrelated or haploidentical donor (1 point), and recipient/donor CMV serostatus (+/+; 2 points, ±; 3 points). We have administered LTV to patients with a total score of ≥4 points. We then focused on 143 patients who underwent allo-HCT when we applied this strategy (Period 2). Forty patients (28%) in Period 2 received LTV prophylaxis. Two patients (5.4%) exhibited higher CMV-AUC among 37 patients in the higher-risk group (≥4 points). However, as many as 33% of the patients with 3 points in Period 2 experienced higher CMV-AUC. Notably, in the lower-risk patients of Period 2, 68% of patients who received systemic steroids for acute graft-versus-host-disease (GVHD) developed higher CMV-AUC. Our risk-adapted LTV prophylaxis strategy effectively prevented higher CMV-AUC in the higher-risk group and reduced the use of LTV. Additionally, including the use of systemic steroids for acute GVHD in this risk-adapted approach is preferable.

Cytomegalovirus in haematopoietic cell transplantation - The troll is still there

Patients undergoing allogeneic haematopoietic cell transplantation are prone to complications caused by viral infections. Cytomegalovirus (CMV) considerably impacts transplantation as it frequently requires antiviral intervention that evokes substantial side effects depending on the antiviral drug. Intermittent antiviral treatment may become necessary if CMV DNAemia cannot be permanently suppressed, and drug resistance may emerge that hampers and prolongs treatment. Despite sedulous endeavours, vaccination against CMV is not yet available. This review concisely summarises current approaches in managing CMV infection comprising risk factors, diagnostics including indications for resistance testing, and therapeutic options from antiviral drugs to virus-specific T cells.

Real-world experience with letermovir for cytomegalovirus-prophylaxis after allogeneic hematopoietic cell transplantation: A multi-centre observational study

OBJECTIVES

Efficacy and safety of letermovir as prophylaxis for clinically significant cytomegalovirus infections (csCVMi) was evaluated in randomised controlled trials while most of the real-world studies are single-centre experiences.

METHODS

We performed a retrospective, multi-centre case-control study at six German university hospitals to evaluate clinical experiences in patients receiving CMV prophylaxis with letermovir (n = 200) compared to controls without CMV prophylaxis (n = 200) during a 48-week follow-up period after allogeneic hematopoietic cell transplantation (aHCT).

RESULTS

The incidence of csCMVi after aHCT was significantly reduced in the letermovir (34%, n = 68) compared to the control group (56%, n = 112; p < 0.001). Letermovir as CMV prophylaxis (OR 0.362) was found to be the only independent variable associated with the prevention of csCMVi. Patients receiving letermovir showed significantly better survival compared to the control group (HR = 1.735, 95% CI: 1.111-2.712; p = 0.014). Of all csCMVi, 46% (n = 31) occurred after discontinuation of letermovir prophylaxis. Severe neutropenia (<500 neutrophils/µL) on the day of the stem cell infusion was the only independent variable for an increased risk of csCMVi after the end of letermovir prophylaxis.

CONCLUSIONS

Our study highlights the preventive effects of letermovir on csCMVi after aHCT. A substantial proportion of patients developed a csCMVi after discontinuation of letermovir. In particular, patients with severe neutropenia require specific attention after drug discontinuation.

Letermovir for cytomegalovirus infection in allogeneic hematopoietic stem-cell transplantation: tips and notes for effective use in clinical practice

INTRODUCTION

Cytomegalovirus (CMV) infection remains a major complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). While conventional antiviral agents such as ganciclovir can be used for CMV prophylaxis, toxicities such as myelosuppression are a major concern.

AREA COVERED

This work aimed to summarize the latest information and practical issues regarding a new anti-CMV agent, letermovir (LET).

EXPERT OPINION

LET inhibits CMV replication by binding to components of the DNA terminase complex. A phase 3 trial in allo-HSCT recipients showed a reduced incidence of clinically significant CMV infection in the LET group. In 2017, this agent was first approved for CMV prophylaxis in adult CMV-seropositive allo-HSCT recipients in the United States, and is now used worldwide. While LET has an excellent toxicity profile, there are issues to be aware of, such as interactions with other drug classes (e.g. immunosuppressants and antifungals) and reactivation of CMV infection following LET cessation. While LET is the current standard of care for CMV prophylaxis, there are no established protocols for preemptive treatment of asymptomatic CMV viremia or for treatment of developed CMV disease. Further research is needed to maximize the benefits of LET, including the discovery of biomarkers.