How I treat CMV reactivation after allogeneic hematopoietic stem cell transplantation

Haploidentical hematopoietic stem cell transplantation for hematologic malignancies: a novel conditioning regimen with anti-T lymphocyte immunoglobulin instead of anti-thymocyte globulin for in vivo T cell depletion

We evaluated the safety and efficacy of a novel protocol for haploidentical stem cell transplantation (haplo-SCT) in 312 patients with hematologic malignancies. The protocol evolved from the Beijing platform replacing ATG with ATLG; adding Fludarabine and removing cytarabine and Simustine. GVHD prophylaxis combined Basiliximab and low-dose cyclophosphamide post-transplant; overall, the conditioning duration was shortened. Median times to neutrophil and platelet recovery were both 11 days. Graft rejection occurred in 0.96% of patients. Cumulative incidences of grades II-IV and III-IV acute GVHD by day 200 were 35.3% and 8.9%, respectively. Probabilities of total and extensive chronic GVHD at 2 years were 40.7% and 14.7%. CMV viremia was observed in 35.6% of patients, with a 1.9% 100-day CMV pneumonia incidence and no CMV-related mortality. Cumulative incidences of non-relapse mortality at 100 days, 1 year, and 2 years were 2.9, 4.4, and 6.6%. The 4-year OS, RFS, and GRFS rates were 78.9, 70.7, and 47.3%. Older recipient age was associated with higher NRM, while positive pre-transplant MRD predicted worse OS, RFS, and higher relapse incidence. Our novel protocol for haplo-SCT is associated with low infection rates and acceptable risks of graft failure, severe GVHD, and mortality, representing a safe and effective haploidentical transplantation strategy.

Role of cytomegalovirus reactivation on relapse after allogeneic hematopoietic stem cell transplantation in acute lymphoblastic leukemia

Cytomegalovirus reactivation (CMV-R) is a frequent complication post-allogeneic hematopoietic stem cell transplantation (allo-HSCT), associated with poor outcomes. Previous studies have demonstrated the protective effect of CMV-R against relapse after allo-HSCT for acute myeloblastic leukemia (AML). However, this impact remains unclear in acute lymphoblastic leukemia (ALL). We conducted a retrospective study on 81 patients with ALL who received allo-HSCT after myeloablative conditioning regimen from matched sibling donors between 2016 and 2022. All patients underwent weekly monitoring for CMV-R by quantitative polymerase chain reaction assay from engraftment until day +100 post allo-HSCT, and received antiviral prophylaxis with acyclovir from day +1 to 6 months after allo-HSCT. Preemptive treatment was initiated when a viremia was higher than 150 copies/mL. The median age was 20 years (range, 5-50 years). After allo-HSCT, 35% of patients developed CMV-R after a median of 39 days (range, 19-100 days). After a median follow-up of 30 months (range, 1-93 months), CMV-R was an independent factor associated with lower cumulative incidence of relapse (CIR) (OR: 0.17; 95% CI [0.03 - 0.98], p = 0.04) without survival benefit. Further studies are needed to validate the protective effect of CMV-R on ALL relapse.

Effectiveness of letermovir in preventing cytomegalovirus reactivation after cord blood transplantation

BACKGROUND

Cord blood transplantation (CBT) is associated with a high risk of cytomegalovirus (CMV) infection. Letermovir (LTV) is a prophylactic agent against CMV reactivation after CBT, but data on its effectiveness and the incidence of late CMV reactivation after LTV discontinuation are limited.

METHODS

A single-center retrospective observational study was conducted in 79 adult CMV-seropositive CBT recipients who received their first transplant for acute myeloid leukemia, acute lymphoblastic leukemia, or myelodysplastic syndrome from February 2016 to September 2022. Outcomes were compared between 45 patients who received LTV prophylaxis and 34 patients who did not.

RESULTS

The cumulative incidence of CMV reactivation was significantly lower in patients who received LTV prophylaxis at both day 100 (11.1 % vs. 82.4 %, p < 0.001) and 1 year (45.3 % vs. 82.4 %, p < 0.001). The incidence of late CMV reactivation after LTV discontinuation was 34.2 %. The cumulative incidence of CMV disease was comparable between patients who received and those who did not (0 % vs. 8.8 % at day 100, 2.3 % vs. 8.8 % at 1 year; p = 0.181). Multivariate analysis showed that LTV prophylaxis reduced the cumulative incidence of CMV reactivation (hazard ratio 0.20, 95 % confidence interval 0.09 to 0.42, p < 0.001).

CONCLUSION

LTV prophylaxis is strongly associated with prevention of CMV reactivation after CBT. Due to the high incidence of late CMV reactivation, close monitoring is required after LTV discontinuation and extension of LTV prophylaxis beyond day 100 should be considered.

Analysis of spontaneous cytomegalovirus clearance after low level reactivation using a pre-emptive treatment threshold of 4,000 IU/mL in allogeneic hematopoietic cell transplant recipients

BACKGROUND

Cytomegalovirus (CMV) can be a serious complication after allogeneic hematopoietic cell transplant (HCT). CMV viral load is routinely monitored, and pre-emptive therapy is initiated to prevent CMV viremia from developing into CMV organ disease based on institutional thresholds. There is no established universal threshold for pre-emptive therapy and many centers utilize different strategies.

METHODS

Allogeneic HCT recipients at WVU Medicine from 2009 to 2021 were routinely initiated on pre-emptive CMV treatment for a PCR viral threshold above 4000 IU/mL. Adult patients with quantifiable values below this threshold, were analyzed to evaluate the rate of spontaneous clearance without initiation of CMV-directed therapy, during their first episode of CMV reactivation. This study excluded any patients that received letermovir prophylaxis.

RESULTS

Sixty patients were included in the analysis. The spontaneous clearance rate was 60 %. The risk factors that were associated with a lower spontaneous clearance rate were reactivation within thirty days after transplant (p = 0.031), presence of graft-versus-host-disease (p = 0.031), and CMV PCR values of 2500-4000 IU/mL (p = 0.02). Although these patients had lower rates of spontaneous clearance, they still spontaneously cleared in 42 %, 42 %, and 43 % of the cases, respectively.

CONCLUSION

Delaying pre-emptive treatment until a CMV PCR value of 4000 IU/mL is reached appears appropriate and decreases unnecessary treatment toxicity and resistance.

Cytomegalovirus viral load at initiation of pre-emptive antiviral therapy impacts cytomegalovirus dynamics in pediatric allogeneic hematopoietic cell transplantation recipients

BACKGROUND

Cytomegalovirus (CMV) contributes to morbidity and mortality in allogeneic hematopoietic cell transplantation (allo-HCT) recipients. Pre-emptive antiviral therapy (PET) reduces the incidence of CMV end-organ disease (EOD), though relevant viral thresholds to initiate PET remain undefined. We evaluated the impact of viral loads (VLs) at PET initiation on virologic and clinical outcomes following pediatric allo-HCT.

METHODS

Single-center retrospective cohort analysis of children who underwent their first allo-HCT from January 2014 to December 2020. Weekly quantitative plasma CMV polymerase chain reaction was performed until Day +100 and PET was initiated once VL exceeded a pre-defined threshold per institutional guidelines. Patients were followed for 1-year post-HCT to evaluate virologic and clinical outcomes including end-organ disease (EOD), overall survival (OS), and non-relapse mortality (NRM).

RESULTS

Among 146 allo-HCT recipients, CMV DNAemia occurred in 40 patients (27%) at a median of 15 days post-HCT (interquartile range 6-28.5). Ten percent (n = 4) had spontaneous resolution of DNAemia, while 90% (n = 36) required PET. PET initiated when CMV VL was ≥ 1000 IU/mL (n = 21) vs when VL < 1000 IU/mL (n = 15) resulted in higher peak CMV VL (12,670 vs. 1284 IU/mL, p = 0.0001) and longer time to CMV DNAemia resolution (36 vs. 24 days, p = 0.035). There were no differences in EOD, OS, or NRM at 12 months post-HCT based on VL at PET initiation.

CONCLUSIONS

Initiating PET when CMV VL was ≥1000 IU/mL resulted in significantly higher peak VL and prolonged DNAemia, with no differences in EOD, OS, or NRM at 12 months post pediatric HCT.

Cytomegalovirus Infections in Hematopoietic Stem Cell Transplant: Moving Beyond Molecular Diagnostics to Immunodiagnostics

Human CMV, regularly reactivated by simple triggers, results in asymptomatic viral shedding, powerful cellular immune responses, and memory inflation. Immunocompetent individuals benefit from a robust immune response, which aids in viral management without causing clinically significant illness; however, immunodeficient individuals are always at a higher risk of CMV reactivation and disease. Hematopoietic stem cell transplant (HSCT) recipients are consistently at higher risk of CMV reactivation and clinically significant CMV illness due to primary disease, immunosuppression, and graft vs. host disease. Early recovery of CMV-CMI responses may mitigate effects of viral reactivation in HSCT recipients. Immune reconstitution following transplantation occurs spontaneously and is mediated initially by donor-derived T cells, followed by clonal growth of T cells produced from graft progenitors. CMV-specific immune reconstitution post-transplant is related to spontaneous clearance of CMV reactivation and may eliminate the need for prophylactic or pre-emptive medication, making it a potential predictive marker for monitoring CMV reactivation. This review highlights current thoughts and therapeutic options for CMV reactivation in HSCT, with focus on CMV immune reconstitution and post-HSCT monitoring. Immune monitoring aids in risk stratification of transplant recipients who may progress from CMV reactivation to clinically significant CMV infection. Implementing this approach in clinical practice reduces the need for periodic viral surveillance and antiviral therapy in recipients who have a high CMV-CMI and thus may experience self-limited reactivation. Therefore, in the age of precision medicine, it is critical to incorporate CMV-specific cellular immune surveillance into conventional procedures and algorithms for the management of transplant recipients.

Monitoring and Management of Cytomegalovirus Reactivations After Allogeneic Hematopoietic Stem Cell Transplantation in Children: Experience from a Single Pediatric Center

BACKGROUND

CMV reactivation represents a frequent complication after HSCT. The aim of this study was to describe the incidence of CMV reactivation in a pediatric HSCT cohort and analyze the potential impact of recipient/donor-related or transplant-related factors on this complication. Furthermore, we analyzed the management of CMV reactivation in order to purpose criteria for pre-emptive therapy.

METHODS

Allogeneic HSCTs, performed at IRCCS Istituto Gaslini between 2012 and 2022, were included in this analysis. CMV-DNAemia was regularly monitored. Risk stratification was based on donor/recipient serological status and additional potential risk factors were considered: haploidentical transplant; any HSCT subsequent to the first; acute and chronic GvHD; steroids; and other immunosuppressive therapies. We described also the approach for pre-emptive therapy during the period 2012-2019.

RESULTS

A total of 214 allogeneic HSCTs were performed in 189 patients. In total, 100 (46.7%) HSCTs were complicated by at least one reactivation. CMV reactivation was significantly associated with high serological risk and steroid treatment. Pre-emptive therapy was administered in 59/69 (85.5%) HSCTs during 2012-2019. In the presence of predefined risk conditions, therapy was started at a median viremia of 2050 copies/mL. No difference was observed in OS between patients with CMV reactivation versus patients who did not present this complication.

CONCLUSIONS

These results suggest the potential effectiveness of the approach used in providing pre-emptive therapy based on viral load monitoring and individualized risk factors.

[Management of Cytomegalovirus Infection in Allogeneic Hematopoietic Stem Cell Transplant Recipients]

Cytomegalovirus (CMV) is a type of double-stranded deoxyribonucleic acid virus belonging to the herpesviridae family. Following a primary infection, the virus becomes latent in various types of white blood cells. Cytomegalovirus infection can remain latent or become active, especially in immunocompromised individuals, such as those undergoing hematopoietic stem cell transplantation (HSCT), where CMV reactivation can occur. In this context, CMV infection is common and associated with high rates of morbidity and mortality. Pneumonia is one of the most serious complications, with mortality rates exceeding 50%. Additionally, even in the absence of organ-specific disease, CMV infection is related to increased mortality unrelated to hematologic neoplasm recurrence. Given the frequency and severity of this infection in HSCT patients, it is crucial to implement effective strategies for monitoring, prevention, and treatment. This guideline was developed to identify patient groups that benefit from a systematic approach to CMV infection and to define the most appropriate strategy for each group. Monitoring CMV viral load in peripheral blood is crucial, especially in patients at moderate to high risk of active infection. Primary prophylaxis with letermovir (an antiviral drug) is recommended to reduce the incidence of active infection, especially in high-risk patients. Secondary prophylaxis with valganciclovir (antiviral drug) is recommended after an episode of active infection, while preemptive and disease treatment is based on monitoring viral load and clinical response. The aim of this guideline is to improve the approach to CMV infection in HSCT patients, ensuring an effective and safe preventive and therapeutic approach.

Impact of cytomegalovirus (CMV) seroconversion pre-allogeneic hematopoietic cell transplantation on posttransplant outcomes

Cytomegalovirus (CMV) reactivation post-allogeneic hematopoietic cell transplantation (post-alloHCT) increases morbidity and mortality. We sought to determine the frequency of CMV seroconversion in patients pre-alloHCT and to investigate the impact on posttransplant outcomes. We retrospectively investigated 752 adult patients who underwent alloHCT at our center from January 2015 to February 2020 before the adoption of letermovir prophylaxis. CMV serology was assessed at consult and pretransplant. The cohort was divided into four groups based on pretransplant CMV seroconversion: negative to positive (Group 1), positive to negative (Group 2), consistently negative (Group 3), and consistently positive (Group 4). Eighty-nine patients (12%) had seroconverted from negative to positive, 17 (2%) from positive to negative, 151 (20%) were consistently seronegative, and 495 (66%) were consistently seropositive pretransplant. For the four CMV serostatus groups, cumulative incidence of CMV reactivation at 6 months posttransplant was 4.5%, 47.1%, 6.6%, and 76.6% for Groups 1, 2, 3, and 4, respectively (p < .0001). No differences between groups were seen regarding Grade III-IV acute graft-versus-host disease (GVHD) (p = .91), moderate/severe chronic GVHD (p = .41), or graft failure (p = .28). On multivariable analysis, there was no impact of CMV serostatus group on overall survival (p = .67), cumulative incidence of relapse (p = .83) or non-relapse mortality. alloHCT patients who demonstrate CMV seroconversion pretransplant from negative to positive have a very low risk of CMV reactivation posttransplant. The observed seroconversion may be due to passive CMV immunity acquired through blood products. Quantitative CMV immunoglobulin G/immunoglobulin M pretransplant may help differentiate between true seroconversion and passively transmitted CMV immunoglobulin.

CMV reactivation during pretransplantation evaluation: a novel risk factor for posttransplantation CMV reactivation

ABSTRACT

Cytomegalovirus (CMV) disease occurs occasionally before allogeneic hematopoietic cell transplantation (HCT) and is associated with poor post-HCT outcomes; however, the impact of pre-HCT CMV reactivation is unknown. Pre-HCT CMV reactivation was assessed in HCT candidates from the preemptive antiviral therapy (2007-2017) and letermovir prophylaxis (2018-2021) eras. CMV DNA polymerase chain reaction (PCR) surveillance was routinely performed during the pre-HCT workup period, and antiviral therapy was recommended according to risk of progression to CMV disease. Risk factors for pre-HCT CMV reactivation were characterized, and the associations of pre-HCT CMV reactivation with post-HCT outcomes were examined using logistic regression and Cox proportional hazard models, respectively. A total of 1694 patients were identified, and 11% had pre-HCT CMV reactivation 14 days (median; interquartile range [IQR], 6-23) before HCT. Lymphopenia (≤0.3 × 103/μL) was the strongest risk factor for pre-HCT CMV reactivation at multiple PCR levels. In the preemptive therapy era, patients with pre-HCT CMV reactivation had a significantly increased risk of CMV reactivation by day 100 as well as CMV disease and death by 1 year after HCT. Clearance of pre-HCT CMV reactivation was associated with a lower risk of post-HCT CMV reactivation. Similar associations with post-HCT CMV end points were observed in a cohort of patients receiving letermovir prophylaxis. Pre-HCT CMV reactivation can be routinely detected in high-risk HCT candidates and is a significant risk factor for post-HCT CMV reactivation and disease. Pre-HCT CMV DNA PCR surveillance is recommended in high-risk HCT candidates, and antiviral therapy may be indicated to prevent post-HCT CMV reactivation.

Evaluation of the AltoStar AM16 system for the quantitation of AdV, CMV and HHV-6 DNA from clinical specimens

The vulnerability of immunocompromised patients to common or opportunistic viral infections is particularly high. The quantitation of viral load in clinical specimens is important for the diagnosis and management of the infection and reactivation in this patient population, particularly transplant recipients. As the new regulation "IVDR" regarding in vitro diagnosis methods is about to come into effect in France, diagnostic laboratories have to implement methods and systems compatible with this new regulation. Technical performance of the AltoStar® Adenovirus (AdV), Cytomegalovirus (CMV) and human Herpesvirus-6 (HHV-6) DNA PCR Kits 1.5 was assessed on the AltoStar Automation system AM16 using reference kits in 146 clinical samples. Overall agreement in clinical specimens was 87.5 % (28/32), 96.8 % (62/64), 100 % (22/22), 100 % (28/28) and 92.8 % (26/28) for AdV, CMV (WB samples and other matrices), HHV-6 A&B respectively. Quantitative results were highly correlated and estimated to be equivalent within a 0.057-0.648 log-amount difference.We found that altona kits on The AltoStar AM16 system are suitable for clinical monitoring of AdV, CMV and HHV-6 in immunocompromised hosts.

Update on Cytomegalovirus Infection Management in Allogeneic Hematopoietic Stem Cell Transplant Recipients. A Consensus Document of the Spanish Group for Hematopoietic Transplantation and Cell Therapy (GETH-TC)

Background

Cytomegalovirus (CMV) infection is a common complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT) and in patients receiving novel hematological therapies. Its impact on morbidity and mortality necessitates effective management strategies. Despite recent advances in diagnostics and treatment, unresolved questions persist regarding monitoring and treatment, prompting the need for updated recommendations.

Methods

A consensus was reached among a panel of experts selected for their expertise in CMV research and clinical practice. Key clinical areas and questions were identified based on previous surveys and literature reviews. Recommendations were formulated through consensus and graded using established guidelines.

Results

Recommendations were provided for virological monitoring, including the timing and frequency of CMV DNAemia surveillance, especially during letermovir (LMV) prophylaxis. We evaluated the role of CMV DNA load quantification in diagnosing CMV disease, particularly pneumonia and gastrointestinal involvement, along with the utility of specific CMV immune monitoring in identifying at-risk patients. Strategies for tailoring LMV prophylaxis, managing breakthrough DNAemia, and implementing secondary prophylaxis in refractory cases were outlined. Additionally, criteria for initiating early antiviral treatment based on viral load dynamics were discussed.

Conclusion

The consensus provides updated recommendations for managing CMV infection in hematological patients, focusing on unresolved issues in monitoring, prophylaxis, treatment, and resistance. These recommendations aim to guide clinical practice and improve outcomes in this high-risk population. Further research is warranted to validate these recommendations and address ongoing challenges in CMV management with emerging antiviral combinations, particularly in pediatric populations.

Microbiological risk factors, ICU survival, and 1-year survival in hematological patients with pneumonia requiring invasive mechanical ventilation

PURPOSE

To identify pathogenic microorganisms and microbiological risk factors causing high morbidity and mortality in immunocompromised patients requiring invasive mechanical ventilation due to pneumonia.

METHODS

A retrospective single-center study was performed at the intensive care unit (ICU) of the Department of Internal Medicine at Heidelberg University Hospital (Germany) including 246 consecutive patients with hematological malignancies requiring invasive mechanical ventilation due to pneumonia from 08/2004 to 07/2016. Microbiological and radiological data were collected and statistically analyzed for risk factors for ICU and 1-year mortality.

RESULTS

ICU and 1-year mortality were 63.0% (155/246) and 81.0% (196/242), respectively. Pneumonia causing pathogens were identified in 143 (58.1%) patients, multimicrobial infections were present in 51 (20.7%) patients. Fungal, bacterial and viral pathogens were detected in 89 (36.2%), 55 (22.4%) and 41 (16.7%) patients, respectively. Human herpesviruses were concomitantly reactivated in 85 (34.6%) patients. As significant microbiological risk factors for ICU mortality probable invasive Aspergillus disease with positive serum-Galactomannan (odds ratio 3.1 (1.2-8.0), p = 0.021,) and pulmonary Cytomegalovirus reactivation at intubation (odds ratio 5.3 (1.1-26.8), p = 0.043,) were identified. 1-year mortality was not significantly associated with type of infection. Of interest, 19 patients had infections with various respiratory viruses and Aspergillus spp. superinfections and experienced high ICU and 1-year mortality of 78.9% (15/19) and 89.5% (17/19), respectively.

CONCLUSIONS

Patients with hematological malignancies requiring invasive mechanical ventilation due to pneumonia showed high ICU and 1-year mortality. Pulmonary Aspergillosis and pulmonary reactivation of Cytomegalovirus at intubation were significantly associated with negative outcome.

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.

Antiviral Agents for Preventing Cytomegalovirus Disease in Recipients of Hematopoietic Cell Transplantation

This systematic review discusses the use of prophylaxis to prevent cytomegalovirus (CMV) infection in recipients who have undergone hematopoietic cell transplantation. It highlights the need for new approaches to control and prevent CMV infection. The approval of the anti-CMV drug letermovir has made antiviral prophylaxis more popular. CMV-specific T cell-mediated immunity tests are effective in identifying patients who have undergone immune reconstitution and predicting disease progression. Maribavir (MBV) has been approved for the treatment of post-transplant CMV infection/disease in adolescents. Adoptive T-cell therapy and the PepVax CMV vaccine show promise in tackling refractory and resistant CMV. However, the effectiveness of PepVax in reducing CMV viremia/disease was not demonstrated in a phase II trial. Cell-mediated immunity assays are valuable for personalized management plans, but more interventional studies are needed. MBV and adoptive T-cell therapy are promising treatments, and trials for CMV vaccines are ongoing.

Impact of Early Cytomegalovirus Reactivation After Allogeneic Hematopoietic Stem Cell Transplantation on Relapse in Patients With Myelodysplastic Syndrome: A Nationwide Retrospective Study From Adult Myelodysplastic Syndrome Working Group of the JSTCT

Cytomegalovirus (CMV) reactivation is a prominent complication associated with adverse outcomes in allogeneic hematopoietic stem cell transplantation (HSCT). However, CMV reactivation after allogeneic HSCT may be associated with a lower incidence of relapse in some hematological malignancies. This study analyzed the Japanese registry data from 1082 patients with myelodysplastic syndrome (MDS) who underwent their first allogeneic HSCT and survived for 100 days after transplantation without graft failure or disease relapse to investigate this association. Patients who received cord blood transplants, demonstrated in vivo T cell depletion, underwent prophylactic anti-CMV treatment, or diagnosed with secondary MDS were excluded. CMV reactivation measured by pp65 antigenemia within 100 days after allogeneic HSCT was observed in 57.5% of patients, with a median time of 46 days from transplant. The 5-yr overall survival and cumulative incidence of relapse (CIR) in the cohort were 60.5% and 15.6%, respectively. The 5-yr CIR showed no significant difference between patients with and without CMV reactivation (14.4% versus 17.2%; P = .185). Interestingly, CMV reactivation within 100 days was significantly associated with a lower 5-yr CIR (7.6% versus 16.4%; P = .002) in patients with <5% myeloblasts in the bone marrow (BM) just before HSCT. Furthermore, this relevancy confirmed even when excluding patients with Grade II to IV acute GVHD (Hazard ratio: 0.38; 95% confidential intervals: 0.18-0.801; P = .011). Our findings indicate a correlation between early CMV reactivation and MDS relapse, based on the proportion of myeloblasts in the BM. These results may contribute to the development of effective CMV prophylaxis post-HSCT.

Real-World Safety and Effectiveness of Letermovir in Patients Undergoing Allogenic Hematopoietic Stem Cell Transplantation: Final Results of Post-Marketing Surveillance in Japan

BACKGROUND AND OBJECTIVE

Cytomegalovirus (CMV) is a common opportunistic infection after allogenic hematopoietic stem cell transplantation (allo-HSCT). Letermovir, an inhibitor of CMV DNA terminase, is approved for CMV prophylaxis in allo-HSCT patients. We report the final results of post-marketing surveillance of letermovir in Japan.

METHODS

The case report forms were drafted in part by the Japanese Data Center for Hematopoietic Cell Transplantation using data elements in the Transplant Registry Unified Management Program and sent to individual HSCT centers to decrease the burden of reporting. Hematopoietic stem cell transplantation patients who received letermovir between May 2018 and May 2022 were registered. Data collected included physician-assessed adverse events/adverse drug reactions and clinical effectiveness (development of CMV disease, CMV antigen status, and use of preemptive therapy).

RESULTS

A total of 821 HSCT patients were included in the safety analyses. Adverse drug reactions occurred in 11.33% of patients, with serious adverse drug reactions in 3.05%. The five most common adverse drug reactions were nausea (1.58%), renal impairment (1.46%), and acute graft versus host disease, CMV test positive, and hepatic function abnormal (0.61% each). A total of 670 patients were eligible for effectiveness analyses. Among these patients, 16.57% and 28.66% required preemptive therapy through week 14 and week 48, respectively. In addition, relatively few patients developed CMV disease throughout the follow-up period (1.34% at week 14 and 3.85% at week 48).

CONCLUSIONS

This final analysis of post-marketing surveillance with up to 48 weeks follow-up period in Japan provides further evidence supporting the safety profile and effectiveness of letermovir for CMV prophylaxis in patients undergoing allo-HSCT in real-world settings.

Incidence of Cytomegalovirus Infection After Repeat Keratoplasty and Associated Rate of Graft Failure

INTRODUCTION

The aim of this work was to compare the prognosis and characteristics of patients with Cytomegalovirus (CMV) infection (CMV+) with those of patients without virus infection (Virus-) undergoing repeat keratoplasty.

METHODS

This prospective propensity score-matched cohort study enrolled patients who underwent repeat keratoplasty for graft failure at the Peking University Third Hospital between January 2016 and May 2022. Patients with prior viral keratitis before the first keratoplasty were excluded. The primary outcome measure was the graft failure rate. The secondary outcome measures included the anterior segment characteristics, intraocular pressure (IOP), and endothelial cell density.

RESULTS

Ninety-four matched patient pairs were included. The graft failure rate in the CMV+ group (71%) was higher than that in the Virus- group (29%) (P < 0.001). CMV infection in the cornea increased the risk of repeat graft failure and shortened the median survival time (hazard ratio, 3.876; 95% confidence intervals, 2.554-5.884; P < 0.001). The characteristics of graft failure included exacerbation of ocular surface inflammation, neovascularization, and opacification. Epithelial defects, high IOP, and endothelial decompensation were observed at an increased frequency in the CMV+ group (all P < 0.005). Recurrent CMV infection presented as early endothelial infection in the CMV+ group. Recurrence of CMV infection was confined to the graft endothelium without involving the stroma and epithelium post-repeat endothelial keratoplasty.

CONCLUSIONS

CMV infection post-keratoplasty leads to persistent endothelial damage and graft opacification and significantly increases the risk of repeat graft failure. Localized recurrence of CMV infection in the endothelial grafts underscores the importance of monitoring and treatment.

TRIAL REGISTRATION

Chictr.org.cn, ChiCTR1800014684.

Engineered HCMV-infected APCs enable the identification of new immunodominant HLA-restricted epitopes of anti-HCMV T-cell immunity

Complications due to HCMV infection or reactivation remain a challenging clinical problem in immunocompromised patients, mainly due to insufficient or absent T-cell functionality. Knowledge of viral targets is crucial to improve monitoring of high-risk patients and optimise antiviral T-cell therapy. To expand the epitope spectrum, genetically-engineered dendritic cells (DCs) and fibroblasts were designed to secrete soluble (s)HLA-A*11:01 and infected with an HCMV mutant lacking immune evasion molecules (US2-6 + 11). More than 700 HLA-A*11:01-restricted epitopes, including more than 50 epitopes derived from a broad range of HCMV open-reading-frames (ORFs) were identified by mass spectrometry and screened for HLA-A*11:01-binding using established prediction tools. The immunogenicity of the 24 highest scoring new candidates was evaluated in vitro in healthy HLA-A*11:01+/HCMV+ donors. Thus, four subdominant epitopes and one immunodominant epitope, derived from the anti-apoptotic protein UL36 and ORFL101C (A11SAL), were identified. Their HLA-A*11:01 complex stability was verified in vitro. In depth analyses revealed highly proliferative and cytotoxic memory T-cell responses against A11SAL, with T-cell responses comparable to the immunodominant HLA-A*02:01-restricted HCMVpp65NLV epitope. A11SAL-specific T cells were also detectable in vivo in immunosuppressed transplant patients and shown to be effective in an in vitro HCMV-infection model, suggesting their crucial role in inhibiting viral replication and improvement of patient's outcome. The developed in vitro pipeline is the first to utilise genetically-engineered DCs to identify naturally presented immunodominant HCMV-derived epitopes. It therefore offers advantages over in silico predictions, is transferable to other HLA alleles, and will significantly expand the repertoire of viral targets to improve therapeutic options.

Comparison of valganciclovir versus foscarnet for the treatment of cytomegalovirus viremia in adult acute leukemia patients after allogeneic hematopoietic cell transplantation

Cytomegalovirus (CMV) reactivation increases treatment-related mortality (TRM) after allogeneic hematopoietic cell transplantation (allo-HCT). We analyzed 141 adult acute leukemia (AL) patients suffered allo-HCT between 2017 and 2021, who developed CMV viremia post-HCT and treated with valganciclovir or foscarnet, to evaluate effectiveness and safety of both drugs. Viremia clearance rates (14 and 21 d post treatment) and toxicities were similar in two groups. However, valganciclovir was associated with a lower cumulative incidence of CMV recurrence within 180 days (16.7% vs. 35.7%, p=0.029) post CMV clearance. Finally, 2-year TRM was lower in valganciclovir group (9.7% ± 0.2% vs. 26.2% ± 0.3%, p = 0.026), result a superior 2-year overall survival (OS; 88.1% ± 5.2% vs. 64.4% ± 5.5%, p = 0.005) and leukemia-free survival (LFS; 82.0% ± 5.9% vs. 58.9% ± 5.6%, p = 0.009). Valganciclovir might decrease CMV viremia recurrence and led to better long-term outcome than foscarnet in adult AL patients developed CMV viremia post-HCT. Considering the inherent biases of retrospective study, well-designed trials are warranted to validate our conclusion.

A phase II randomized, placebo-controlled, multicenter trial to evaluate the efficacy of cytomegalovirus PepVax vaccine in preventing cytomegalovirus reactivation and disease after allogeneic hematopoietic stem cell transplant

Not available.

Case Report: Approaches for managing resistant cytomegalovirus in pediatric allogeneic hematopoietic cell transplantation recipients

The instructional case is a pediatric haploidentical TCRαβ+/CD19+ depleted allogeneic hematopoietic cell transplantation recipient who developed early onset CMV infection, which was complicated by resistant CMV (both UL97 and UL54) and successfully managed with maribavir and haploidentical CMV-specific T lymphocytes. Novel approaches to resistant CMV infection are reviewed and effective utilization of recent advances in diagnosis and management of resistant CMV in pediatric HCT are highlighted.

Retrospective Evaluation of Cystatin C as a Measure of Renal Function in Pediatric Hematopoietic Stem Cell Transplant Patients Receiving Foscarnet for Cytomegalovirus Reactivation

BACKGROUND

Cytomegalovirus (CMV) infection following allogeneic hematopoietic cell transplantation has considerable morbidity and mortality, and foscarnet is a treatment option that requires renal dose adjustment. Serum creatinine (SCr)-based estimated glomerular filtration rate (eGFR) equations are used to estimate renal function for patients receiving foscarnet, but cystatin C (cysC) has been shown as a possible alternative. Data examining cysC-based eGFR in this population is sparse. Our primary objective was to evaluate outcomes of patients treated with foscarnet dosed utilizing cysC-based eGFR versus SCr-based eGFR.

METHODS

We analyzed patients on the transplantation and cellular therapies service at Memorial Sloan Kettering Kids from January 2011 to September 2021 who received allogeneic hematopoietic cell transplantation and ≥14 days of foscarnet for CMV infection. Patients with cysC-based eGFR were compared to a historical cohort of patients who only had SCr-based eGFR. Outcomes included time to CMV clearance, death or change in anti-CMV therapy. Cumulative incidence curves and cause-specific hazards model were used for analysis.

RESULTS

In 61 analyzed patients, no differences were found between the cohorts in cumulative incidence of change in anti-CMV therapy ( P = 0.17) or death ( P = 0.69). After adjustment for multiple confounders, patients in the SCr cohort seemed to have a higher chance of CMV clearance compared with the cysC cohort, but the difference was not statistically significant (hazard ratio = 2.42, P = 0.089). Patients who received corticosteroids appeared to have lower incidence of CMV clearance ( P = 0.056).

CONCLUSIONS

We did not find differences in outcomes when dosing foscarnet using cysC versus SCr for treatment of CMV infection.

Improving the safety of CAR-T-cell therapy: The risk and prevention of viral infection for patients with relapsed or refractory B-cell lymphoma undergoing CAR-T-cell therapy

Chimeric antigen receptor (CAR) T-cell therapy, an innovative immunotherapeutic against relapsed/refractory B-cell lymphoma, faces challenges due to frequent viral infections. Despite this, a comprehensive review addressing risk assessment, surveillance, and treatment management is notably absent. This review elucidates immune response compromises during viral infections in CAR-T recipients, collates susceptibility risk factors, and deliberates on preventive strategies. In the post-pandemic era, marked by the Omicron variant, new and severe threats to CAR-T therapy emerge, necessitating exploration of preventive and treatment measures for COVID-19. Overall, the review provides recommendations for viral infection prophylaxis and management, enhancing CAR-T product safety and recipient survival.

Application of CMV-IVIg as prophylaxis against cytomegalovirus reactivation in allogeneic hematopoietic stem cell transplantation patients

Cytomegalovirus (CMV) reactivation remains one of the major and life-threatening complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Yet, there is still a lack of safe and effective ways to prevent CMV reactivation in allo-HSCT patients. Here, we retrospectively analyzed a cohort of patients who underwent HSCT at our transplant center between 2018 and 2022 to evaluate the efficacy of prophylactic CMV-specific intravenous immunoglobulin (CMV-IVIg) against CMV reactivation. After Propensity Score Matching, the CMV reactivation rate was significantly decreased in the CMV-IVIg group (HR, 2.952; 95% CI,1.492-5.841; P = .002) compared with the control group. Additionally, the time duration of CMV reactivation (P = .001) and bacterial infection rate (P = .013) were significantly lower in the CMV-IVIg group. Moreover, prophylactic CMV-IVIg was more effective in CMV seropositive patients who received ATG as part of GVHD prevention (HR, 8.225; 95% CI,1.809-37.39; P = .006). In conclusion, CMV-IVIg is considered an effective and safe way to prevent CMV reactivation in HSCT recipients, which may be related to the acceleration of immune reconstitution in the early stage after transplantation.

Treatment for First Cytomegalovirus Infection Post-Hematopoietic Cell Transplant in the AURORA Trial: A Multicenter, Double-Blind, Randomized, Phase 3 Trial Comparing Maribavir With Valganciclovir

BACKGROUND

Neutropenia may limit the use of valganciclovir treatment for cytomegalovirus (CMV) infection following hematopoietic cell transplant (HCT). A phase 2 study indicated efficacy of maribavir with fewer treatment-limiting toxicities than valganciclovir.

METHODS

In this multicenter, double-blind, phase 3 study, patients with first asymptomatic CMV infection post-HCT were stratified and randomized 1:1 to maribavir 400 mg twice daily or valganciclovir (dose-adjusted for renal clearance) for 8 weeks with 12 weeks of follow-up. The primary endpoint was confirmed CMV viremia clearance at week 8 (primary hypothesis of noninferiority margin of 7.0%). The key secondary endpoint was a composite of the primary endpoint with no findings of CMV tissue-invasive disease at week 8 through week 16. Treatment-emergent adverse events (TEAEs) were assessed.

RESULTS

Among patients treated (273 maribavir; 274 valganciclovir), the primary endpoint of noninferiority of maribavir was not met (maribavir, 69.6%; valganciclovir, 77.4%; adjusted difference: -7.7%; 95% confidence interval [CI]: -14.98, -.36; lower limit of 95% CI of treatment difference exceeded -7.0%). At week 16, 52.7% and 48.5% of patients treated (maribavir and valganciclovir, respectively) maintained CMV viremia clearance without tissue-invasive disease (adjusted difference: 4.4%; 95% CI: -3.91, 12.76). With maribavir (vs valganciclovir), fewer patients experienced neutropenia (16.1% and 52.9%) or discontinued due to TEAEs (27.8% and 41.2%). Discontinuations were mostly due to neutropenia (maribavir, 4.0%; valganciclovir, 17.5%).

CONCLUSIONS

Although noninferiority of maribavir to valganciclovir for the primary endpoint was not achieved based on the prespecified noninferiority margin, maribavir demonstrated comparable CMV viremia clearance during post-treatment follow-up, with fewer discontinuations due to neutropenia. Clinical Trials Registration. NCT02927067 [AURORA].

Differential clinical impact of letermovir prophylaxis according to graft sources: a KSGCT multicenter retrospective analysis

ABSTRACT

Clinically significant cytomegalovirus infection (csCMVi) is frequently observed after allogeneic hematopoietic stem cell transplantation (HSCT) and prophylaxis with letermovir is commonly adopted. However, the clinical benefit of letermovir prophylaxis according to graft sources has not been sufficiently elucidated. We retrospectively analyzed 2194 recipients of HSCT who were CMV-seropositive (236 with letermovir prophylaxis and 1958 without prophylaxis against CMV). csCMVi was significantly less frequent in patients with letermovir prophylaxis than in those without (23.7% vs 58.7% at 100 days after HSCT, P < .001) and the same trend was seen when recipients of bone marrow (BM), peripheral blood stem cell (PBSC), or cord blood (CB) transplantation were separately analyzed. In recipients of BM, nonrelapse mortality (NRM) was significantly lower in the letermovir group at 6 months after HSCT (5.0% vs 14.9%, P = .018), and the same trend was observed in recipients of PBSCs (14.7% vs 24.8%, P = .062); however, there was no statistical significance at 1 year (BM, 21.1% vs 30.4%, P = .67; PBSCs, 21.2% vs 30.4%, P = .096). In contrast, NRM was comparable between recipients of CB with and without letermovir prophylaxis throughout the clinical course (6 months, 23.6% vs 24.3%, P =.92; 1 year, 29.3% vs 31.0%, P = .77), which was confirmed by multivariate analyses. In conclusion, the impact of letermovir prophylaxis on NRM and csCMVi should be separately considered according to graft sources.

Real-Life Data on the Efficacy and Safety of Letermovir for Primary Prophylaxis of Cytomegalovirus in Allogeneic Hematopoietic Stem Cell Recipients: A Single-Center Analysis

Objective

Cytomegalovirus (CMV) reactivation is a life-threatening complication after allogeneic hematopoietic stem cell transplantation (HSCT). Introduction of letermovir (LMV) seems to improve post-transplant outcomes, but delayed-onset CMV reactivation still remains a challenge. In this study, we report on our first experience with LMV prophylaxis in 93 CMV-seropositive adult patients receiving HSCT in our center.

Materials and Methods

We retrospectively analyzed the data of 93 adult CMV-seropositive recipients receiving LMV as CMV prophylaxis after HSCT for hematological malignancies between 2019 and 2023. The starting LMV dose was 480 mg daily, reduced to 240 mg daily for those receiving cyclosporin A co-administration. CMV DNA in the blood was measured by real-time polymerase chain reaction weekly for the first 2 months after transplantation, then every other week until the end of immunosuppressive treatment. LMV was continued to day +100 or to CMV reactivation.

Results

The median recipient age at the time of transplant was 51 (range: 20-71) years. All patients received grafts from peripheral blood, mostly for acute myeloid leukemia (60%). The median time from transplantation to LMV initiation was 3 (range: 0-24) days. While 55% of patients were transplanted from matched related donors, 32% had unrelated donors and 13% underwent haploidentical HSCT. Four patients (4%) had CMV “blips” while on LMV, but the drug was continued and repeated assays were negative. Only 2 patients (2%) experienced CMV reactivation while on LMV, on days 48 and 34 after HSCT, respectively. Seven patients (7%) developed late-onset CMV reactivation after a median of 124 days after HSCT (range: 118-152 days) and they were successfully treated with ganciclovir. CMV disease was not observed. Grade III-IV acute graft-versus-host disease occurred in 6 patients (6%) during LMV treatment. LMV treatment was free of side effects.

Conclusion

LMV prophylaxis was effective in preventing CMV reactivation with a favorable safety profile. CMV reactivation occurred mostly after LMV discontinuation; thus, extending the duration of prophylaxis beyond 100 days could be beneficial.

Refractory human cytomegalovirus infection without evidence of genetic resistance in the UL-54 and UL-97 genes in a pediatric hematopoietic stem cell transplant recipient: a case report

Cytomegalovirus (CMV) infection is a common complication in patients undergoing hematopoietic stem cell transplantation (HSCT). Management of refractory CMV infections, especially in developing countries, can be challenging due to the limited availability of second and third-line antiviral drugs or alternative treatments. Here, we present a case of an 8 years-old patient diagnosed with acute myeloid leukemia. Eight months post-diagnosis, the patient underwent TCR-αβ+/CD19+-depleted haploidentical HSCT. Both the donor and recipient tested positive for anti-CMV IgG and negative for IgM antibodies. Before transplantation, the patient received CMV prophylaxis in the form of intravenous ganciclovir. Post-transplantation, the patient exhibited oscillating CMV viral loads and was diagnosed with a refractory infection. Treatment with ganciclovir, foscarnet, and cidofovir was unsuccessful. Sequencing of UL-54 and UL-97 genes was performed to rule out potential resistance to first-line treatment. Ten months after the HSCT, the child died from hypovolemic shock due to gastrointestinal bleeding. This is the first case reported in Peru and Latin America of a refractory CMV infection in a pediatric HSCT recipient without evidence of clinical symptoms and CMV genetic resistance. This case demonstrates the need for alternative treatments to manage refractory CMV infections, especially in haploidentical HSCT cases where drug resistance is frequent (~15%). Furthermore, this case highlights the importance of using highly sensitive genetic tools to detect mutations associated with virus resistance in a broader range of the viral genome.

Letermovir at a Prophylactic Dose for Cytomegalovirus Infection in Children Undergoing Allogeneic Hematopoietic Stem Cell Transplantation: A Single-Center Retrospective Study in Japan

Cytomegalovirus (CMV) infection is a major complication of hematopoietic stem cell transplantation (HSCT). Previous studies in adults demonstrated that letermovir prophylaxis for 100 d after HSCT reduces the occurrence of CMV infection; however, studies in children are limited. In this study, we aimed to examine the incidence of CMV infection in children who underwent allogeneic HSCT with prophylactic letermovir therapy. A single-center retrospective study was conducted among patients aged ≤17 who underwent allogeneic HSCT. We compared the cumulative incidence of CMV infection, mainly monitored by pp65-antigenemia, after HSCT between patients with and without letermovir prophylaxis (10-12 or 5-6 mg/kg/d when co-administered with cyclosporine) using Gray's test. We analyzed 79 patients with a median follow-up period of 126 d. The median age of these patients was 8.3 years (Interquartile range, 3.7-12.4). Prophylactic letermovir was used in 25 patients. Twenty-five patients developed CMV infection, and the cumulative incidence was 38.9% (95% confidence intervals, 25.0-52.5). The cumulative incidence of CMV infection was not significantly different between the letermovir and no-letermovir groups (33.1 vs. 36.6%, p = 0.228). Meanwhile, the cumulative incidence of CMV infection up to 100 d following HSCT was significantly lower in the letermovir group than in the no-letermovir group (8.0 vs. 32.8%, p = 0.026). Most patients experienced no noticeable adverse effects associated with letermovir; however, one patient discontinued letermovir because of nausea and anorexia. In conclusion, the results of this study suggest that letermovir prophylaxis against CMV infection may be effective in children without severe adverse effects.

Refractory cytomegalovirus infections in Chinese patients receiving allogeneic hematopoietic cell transplantation: a review of the literature

In the absence of prophylactic therapy, cytomegalovirus (CMV) viremia is a common complication following allogeneic hematopoietic cell transplantation (allo-HCT) and represents a significant cause of morbidity and mortality. Approximately 25% of allo-HCT happen in China, where the development and refinement of the 'Beijing protocol' has enabled frequent and increasing use of haploidentical donors. However, refractory CMV infection (an increase by >1 log10 in blood or serum CMV DNA levels after at least 2 weeks of an appropriately dosed anti-CMV medication) is more common among patients with haploidentical donors than with other donor types and has no established standard of care. Here, we review the literature regarding refractory CMV infection following allo-HCT in China.

Patterns of CMV infection after letermovir withdrawal in recipients of posttransplant cyclophosphamide-based transplant

Reactivation of latent cytomegalovirus (CMV) is increased in recipients of allogeneic hematopoietic cell transplantation (allo-HCT) with seropositive CMV using posttransplant cyclophosphamide (PT-Cy)-based graft-versus-host disease (GVHD) prophylaxis. Letermovir, a novel DNA terminase complex inhibitor, reduces the incidence of clinically significant CMV infection (csCMVi) in this population; however, parameters that predict csCMVi after letermovir withdrawal are not well described. Here, we examined clinical and immunological parameters in 294 recipients of PT-Cy-based allo-HCT, including 157 patients with CMV, of whom 80 completed letermovir prophylaxis without csCMVi and subsequently stopped letermovir. In this population, the median duration of letermovir exposure was 203 days (interquartile range [IQR], 160-250 days). After letermovir withdrawal, the 90-day cumulative incidence of csCMVi was 23.0% (95% confidence interval, 14.3-32.8). There were no episodes of CMV end-organ disease. Hypogammaglobulinemia before letermovir discontinuation was predictive of csCMVi (hazard ratio, 0.33; 95% confidence interval, 0.12-0.93; P = .03), whereas T-cell and B-cell reconstitution before letermovir withdrawal were not predictive of csCMVi. Higher numbers of natural killer cells were found before letermovir withdrawal in patients who experienced csCMVi (median, 202 vs 160; P = .03). In recipients with seropositive CMV, CD3+CD4-CD8+ T-cell reconstitution was faster in patients with CMV regardless of letermovir exposure. Taken together, these data suggest that csCMVi after letermovir withdrawal was frequent in patients treated with PT-Cy, despite prolonged exposure. Strategies to boost CMV-specific adaptive immunity in patients with persistent hypogammaglobulinemia is a logical pathway to reduce csCMVi after letermovir withdrawal.

QuantiFERON-CMV and monitor predict cytomegalovirus, mortality, and graft-versus-host disease in transplant recipients

Cytomegalovirus (CMV) is the most prevalent infection in recipients of hematopoietic stem cell transplant (HSCT). QuantiFERON-CMV (QF-CMV) and QuantiFERON-Monitor (QFM) assays were used to test whether immune-competent adult allogeneic HSCT recipients with CMV-specific T cells can control CMV infection or reactivation. Our data demonstrated a significant correlation between CMV infection measured by CMV-antigenemia test and QF-CMV results, graft versus host disease (GvHD), and mortality rates. The QF-CMV test revealed that CMV-specific T cells with higher interferon-γ (IFN-γ) release were correlated with lower CMV infection rates. There was a significant negative association between QF-CMV results, GvHD, and mortality rates. Data showed that a one-unit rise in IFN-γ was linked with a 12.7% reduction in GvHD and a 20.7% reduction in the mortality odds ratio. In addition, a negative correlation was found between QF-M results and CMV infection, with the QFM test predicting protection against CMV infection by 1.9%. This is one of the few studies establishing the QF-CMV test's predictive value for GvHD and mortality, its use to monitor HSCT patients for pre-emptive therapy, and the use of the QFM test to predict CMV infection and mortality in HSCT patients. Thus, these assays could be utilized to optimize preventive and pre-emptive therapy procedures to reduce transplant recipient adverse effects and posttransplant therapy costs.

High-dose aciclovir in CMV infection prophylaxis after allogeneic HSCT: a single-center long-term experience

There is only limited data on cytomegalovirus (CMV) prophylaxis with high-dose (HD) aciclovir after allogeneic hematopoietic stem cell transplantation (allo-HSCT). We performed a retrospective analysis on a total of 179 patients who underwent their allo-HSCT with HD-aciclovir prophylaxis at our center. A clinically significant CMV infection (cs-CMVi) was observed in 56 (31%) cases with a median time of 49 (range 25-147) days after HSCT. A significantly higher CMV infection rate was observed in seropositive recipients with a seronegative donor (74%) compared to seropositive recipients with a seropositive donor, and seronegative recipients with seropositive and seronegative donors (24%, 18%, 7% respectively; p < 0.001). The CMV serostatus was the only significant risk factor for CMV infection in our analysis. CMV disease developed in three patients with CMV-related death in two cases. During HD-aciclovir prophylaxis, we did not observe any medical condition attributable to HD-aciclovir's adverse effects. Compared to published results, we observed a low incidence of cs-CMVi with HD-aciclovir prophylaxis in several patient subgroups, especially in seropositive recipients with a seropositive donor. With respect to the determined threshold, HD-aciclovir prophylaxis seems to have good efficacy in an intermediate cs-CMVi risk patients, but prospective randomized trials would be needed for definite conclusions.

Cytomegalovirus infection in chimeric antigen receptor T-cell recipients

ABSTRACT

Chimeric antigen receptor (CAR) T-cell therapy is an innovative immunotherapy treatment for hematological malignancies. Some of the challenges in using this therapy are the development of cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, immunosuppression, and hypogammaglobulinemia, which can be prolonged and significantly increase patients' risk of infection. Cytomegalovirus (CMV) is well known to cause disease and organ damage in immunocompromised hosts, increasing mortality and morbidity. We present a case of a 64-year-old man with multiple myeloma with a significant history of CMV infection that worsened after CAR T-cell therapy and became challenging to contain because of prolonged cytopenias, progression of myeloma, and development of other opportunistic infections. Strategies for prophylaxis, treatment, and maintenance of CMV infections in CAR T-cell therapy recipients are further warranted.

Expanding the scope of the infectious diseases pharmacist in HCT: Beyond antimicrobial stewardship

BACKGROUND

Infectious disease (ID) pharmacists and antimicrobial stewardship (AMS) programs are integral to the infection management of hematopoietic cell transplant (HCT) recipients demonstrating effective implementation of clinical pathways, de-escalation of empirical antibiotics for febrile neutropenia (FN), allergy assessments, and use of rapid diagnostic testing. The HCT procedure is complex, dynamic, and a high risk for infectious complications. Therefore, there is an important role for an ID and AMS pharmacist to collaborate with the primary treating team, with ongoing care, involving the optimal individual patient prophylactic, pre-emptive and treatment management of infections in this high-risk population.

CONCLUSION

This review highlights key factors for consideration of ID/AMS Pharmacists in relation to HCT, including important aspects in the evaluation of infection risk prior to transplant, risk from donor sources, length of, and changes in immunosuppression, and potential drug-drug interactions from other essential supportive care therapies.

Letermovir and tacrolimus interaction effects in hematopoietic cell transplantation recipients receiving moderate cytochrome P450 3A4 inhibitors for antifungal prophylaxis

INTRODUCTION

Letermovir inhibits cytomegalovirus replication and is approved for the prevention of cytomegalovirus infection in cytomegalovirus seropositive hematopoietic cell transplantation recipients. Studies have found that letermovir coadministration has minimal effect on tacrolimus levels prior to the start of voriconazole, a strong cytochrome P450 (CYP) 3A4 inhibitor. However, data are lacking for hematopoietic cell transplantation recipients receiving letermovir and tacrolimus with moderate CYP 3A4 inhibitors as antifungal prophylaxis.

METHODS

In this retrospective single-center analysis, we reviewed the charts of 92 consecutive adult allogeneic hematopoietic cell transplantation recipients receiving letermovir, tacrolimus, and moderate CYP3A4 inhibitors for antifungal prophylaxis.

RESULTS

Tacrolimus concentration/dose (C/D) ratios were evaluated for the first 7 days pre-letermovir and for the first and second 7-day periods after letermovir. The tacrolimus mean C/D ratios [(ng/mL)/(mg/kg/day)] increased significantly with the addition of letermovir: 172.99 (95% confidence interval (CI): 158.2-187.78) pre-letermovir, 268.66 (95% CI: 244.34-292.98) first-week letermovir, and 312.19 (95% CI: 279.39-344.99) second-week letermovir (P < 0.001). The average dosages (mg/kg) of tacrolimus also decreased significantly across the three-time intervals (P < 0.001). Only four patients experienced clinically significant cytomegalovirus reactivation which required systemic treatment.

CONCLUSION

These results demonstrate a reduction in tacrolimus dosing requirements for patients receiving tacrolimus and letermovir with concomitant moderate CYP3A4 inhibitors. The results of this interaction suggest that frequent monitoring of tacrolimus trough levels is warranted when starting letermovir and that empiric reduction of tacrolimus dosing upon letermovir initiation should be considered.

Significance of CMV reactivation in non-allogeneic stem cell transplant patients with cancers: experience of single tertiary care cancer institute

CMV reactivation is rare in hematological as well as solid organ malignancies in non-allogeneic stem cell transplant settings. An increasing number of patients undergoing active treatment or follow-up and diagnosed with CMV reactivation in recent years prompted us to investigate the risk factors and outcomes of CMV reactivation or disease. This was a hospital-based retrospective study that included 174 cancer patients suspected of CMV reactivation. Among them, forty-one tested positive for CMV viremia. The risk factors for CMV reactivation included the use of steroids in 78% of patients, active cancer in 43.9%, use of a monoclonal antibody rituximab in 31.7%, a history of radiation in 26.8%, and autologous stem cell transplant in 12% of patients. The median age was 36 years, and the most common clinical feature was fever (58.5%; n = 24), followed by GI symptoms (12.1%; n = 5), respiratory symptoms (14.6%; n = 6), cytopenia (7.3%; n = 3), and visual/neurological symptoms (4.8%; n = 2). The mean CMV viral load was 37,332 copies/ml (range: 75.00-633,000.00 copies/ml). Nineteen patients received CMV treatment with an average treatment duration of 81.5 days. The median overall survival was 2 months, with 12.0% of patients alive at 5 years. CMV reactivation is associated with significant morbidity and mortality. We recommend vigilant monitoring of CMV-related symptoms, with a low threshold for testing and treatment, for patients with multiple risk factors for CMV reactivation.

Cytomegalovirus Infection Post-Allogeneic Stem Cell Transplantation: Experience from a Country with High Seropositivity

Cytomegalovirus (CMV) infection is a major cause of morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Limited data are available from developing countries regarding the frequency of CMV infection and treatment outcomes. We enrolled 230 consecutive patients undergoing allogeneic HSCT for various hematologic disorders at the Armed Forces Bone Marrow Transplant Center/National Institute of Blood And Marrow Transplant between February 2017 and December 202. CMV reactivation post-HSCT was monitored weekly starting at day +30 and continuing until day +100, and preemptive antiviral therapy was administered to prevent CMV disease in all HSCT recipients with ≥2000 CMV copies/mL. The median age of the study cohort was 9.5 years (range, .6 to 53 years), and the male:female ratio was 2.4:1. The most frequent indication for HSCT was beta thalassemia major (36.1%), followed by aplastic anemia (23.9%). Malignant disorders constituted 20% of all the patients. Pretransplantation CMV seropositivity was 99.1% for the recipients and 99.5% for the donors. CMV infection was seen in 66.1% of the patients, and the median time to CMV DNAemia was 36 days (range, 12 to 95 days). Preemptive antiviral therapy was administered to 140 patients with a CMV viral load ≥2000 copies/mL (61%). In multivariate analysis, patient age >12 years, steroid administration, and use of mycophenolate mofetil with or without post-transplantation cyclophosphamide was associated with the greatest probability of CMV reactivation. Overall survival was 97.4% in patients without CMV reactivation, compared to 80.3% in those with CMV reactivation (P = .001). Event-free survival was 78.7% in the total study cohort, including 89.7% for patients without CMV reactivation and 73% for patients with CMV reactivation (P = .003). Our study is the first from this region to explore the frequency of CMV seropositivity and CMV infection, risk factors for CMV reactivation, and outcomes of antiviral therapy in HSCT recipients.

Epidemiology, treatment patterns, and disease burden of cytomegalovirus in hematopoietic cell transplant recipients in selected countries outside of Europe and North America: A systematic review

BACKGROUND

Cytomegalovirus (CMV) disease impacts morbidity and mortality in hematopoietic cell transplant (HCT) recipients. This systematic review summarized data on the epidemiology, management, and burden of CMV post-HCT outside of Europe and North America.

METHODS

The MEDLINE, Embase, and Cochrane databases were searched for observational studies and treatment guidelines in HCT recipients across 15 selected countries from Asia-Pacific, Latin America, and Middle East (search period: 1 January 2011-17 September 2021). Outcomes included incidence of CMV infection/disease, recurrence, risk factors, CMV-related mortality, treatments, refractory, resistant CMV, and burden.

RESULTS

Of 2708 references identified, 68 were eligible (67 studies and one guideline; 45/67 studies specific to adult allogeneic HCT recipients). The rates of CMV infection and disease within 1 year of allogeneic HCT were 24.9%-61.2% (23 studies) and 2.9%-15.7% (10 studies), respectively. Recurrence occurred in 19.8%-37.9% of cases (11 studies). Up to 10% of HCT recipients died of CMV-related causes. In all countries, first-line treatment for CMV infection/disease involved intravenous ganciclovir or valganciclovir. Conventional treatments were associated with serious adverse events such as myelosuppression (10.0%) or neutropenia only (30.0%, 39.8%) and nephrotoxicity (11.0%) (three studies), frequently leading to treatment discontinuation (up to 13.6%). Refractory CMV was reported in 2.9%, 13.0%, and 28.9% of treated patients (three studies) with resistant CMV diagnosed in 0%-10% of recipients (five studies). Patient-reported outcomes and economic data were scarce.

CONCLUSION

The incidence of CMV infection and disease post-HCT is high outside of North America and Europe. CMV resistance and toxicity highlight a major unmet need with current conventional treatments.

Virus-Specific T-Cell Therapy for Viral Infections of the Central Nervous System: A Review

Opportunistic viral infections of the central nervous system represent a significant cause of morbidity and mortality among an increasing number of immunocompromised patients. Since antiviral treatments are usually poorly effective, the prognosis generally relies on the ability to achieve timely immune reconstitution. Hence, strategies aimed at reinvigorating antiviral immune activity have recently emerged. Among these, virus-specific T-cells are increasingly perceived as a principled and valuable tool to treat opportunistic viral infections. Here we briefly discuss how to develop and select virus-specific T-cells, then review their main indications in central nervous system infections, including progressive multifocal leukoencephalopathy, CMV infection, and adenovirus infection. We also discuss their potential interest in the treatment of progressive multiple sclerosis, or EBV-associated central nervous system inflammatory disease. We finish with the key future milestones of this promising treatment strategy.

CMV reactivation after allogeneic HCT is associated with a reduced risk of relapse in acute lymphoblastic leukemia

Cytomegalovirus reactivation (CMVR) after allogeneic hematopoietic cell transplantation (HCT) is a frequent complication related to survival outcomes; however, its impact on relapse remains unclear, especially in acute lymphoblastic leukemia (ALL). In this nationwide retrospective study, we included patients with acute myeloid leukemia (AML) and ALL in the first or second complete remission who underwent their first HCT using a pre-emptive strategy for CMVR. Because 90% of cases with CMVR had occurred by day 64 and 90% of cases with grades 2 to 4 acute graft-versus-host disease (GVHD) had occurred by day 58, a landmark point was set at day 65. In landmark analyses, 3793 patients with AML and 2213 patients with ALL who survived without relapse for at least 65 days were analyzed. Multivariate analyses showed that CMVR was associated with a lower incidence of relapse in both AML (hazard ratio [HR], 0.81; 95% confidence interval [CI], 0.69-0.95; P = .009) and ALL (HR, 0.81; 95% CI, 0.66-0.99; P = .045). These findings were confirmed when CMVR was used as the time-dependent covariate. Moreover, our study suggests that the protective effect of CMVR on relapse was independent of acute GVHD. A post-hoc subgroup analysis of combined AML and ALL showed that CMVR had a mild antileukemia effect without effect modification, in contrast to the impact of CMVR on NRM. Our findings may provide important implications for strategies used for CMV prophylaxis after HCT.

Prospects of Cytomegalovirus-Specific T-Cell Receptors in Clinical Diagnosis and Therapy

Human cytomegalovirus (HCMV) is responsible for widespread infections worldwide. In immunocompetent individuals it is typically latent, while infection or reactivation in immunocompromised individuals can result in severe clinical symptoms or even death. Although there has been significant progress in the treatment and diagnosis of HCMV infection in recent years, numerous shortcomings and developmental limitations persist. There is an urgent need to develop innovative, safe, and effective treatments, as well as to explore early and timely diagnostic strategies for HCMV infection. Cell-mediated immune responses are the primary factor controlling HCMV infection and replication, but the protective role of humoral immune responses remains controversial. T-cells, key effector cells of the cellular immune system, are critical for clearing and preventing HCMV infection. The T-cell receptor (TCR) lies at the heart of T-cell immune responses, and its diversity enables the immune system to differentiate between self and non-self. Given the significant influence of cellular immunity on human health and the indispensable role of the TCR in T-cell immune responses, we posit that the impact of TCR on the development of novel diagnostic and prognostic methods, as well as on patient monitoring and management of clinical HCMV infection, will be far-reaching and profound. High-throughput and single-cell sequencing technologies have facilitated unprecedented quantitative detection of TCR diversity. With these current sequencing technologies, researchers have already obtained a vast number of TCR sequences. It is plausible that in the near future studies on TCR repertoires will be instrumental in assessing vaccine efficacy, immunotherapeutic strategies, and the early diagnosis of HCMV infection.

CMV-IgG pre-allogeneic hematopoietic stem cell transplantation and the risk for CMV reactivation and mortality

Cytomegalovirus (CMV) represents one of the most common infectious complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Currently, a common diagnostic test used to stratify the risk for CMV infection in allo-HSCT recipients is the qualitative CMV serology of donor and recipient. A positive serostatus of the recipient is the most important risk factor for CMV reactivation and associated with reduced overall survival post-transplantation (TX). Direct and indirect effects of CMV are involved in the poorer survival outcome. The present study investigated if the quantitative interpretation of anti-CMV IgG before allo-HSCT might serve as a novel parameter for the identification of patients at risk for CMV reactivation and worse outcome post-TX. For this purpose, a cohort of 440 allo-HSCT recipients over a period of 10 years was retrospectively analyzed. Our findings indicated that patients with high CMV IgG pre-allo-HSCT had a higher risk to develop CMV reactivation, including clinically relevant infections, and a worse prognosis 36 months post-allo-HSCT as compared to recipients with low CMV IgG values. In the letermovir (LMV) era, this group of patients might benefit from a closer CMV monitoring, and hence, earlier intervention if needed, especially after discontinuation of prophylaxis.

Genetic Variants Associated with Drug Resistance of Cytomegalovirus in Hematopoietic Cell Transplantation Recipients

Cytomegalovirus (CMV) infection is a serious complication in hematopoietic cell transplantation (HCT) recipients. Drug-resistant strains make it more challenging to treat CMV infection. This study aimed to identify variants associated with CMV drug resistance in HCT recipients and assess their clinical significance. A total of 123 patients with refractory CMV DNAemia out of 2271 HCT patients at the Catholic Hematology Hospital between April 2016 and November 2021 were analyzed, which accounted for 8.6% of the 1428 patients who received pre-emptive therapy. Real-time PCR was used to monitor CMV infection. Direct sequencing was performed to identify drug-resistant variants in UL97 and UL54. Resistance variants were found in 10 (8.1%) patients, and variants of uncertain significance (VUS) were found in 48 (39.0%) patients. Patients with resistance variants had a significantly higher peak CMV viral load than those without (p = 0.015). Patients with any variants had a higher risk of severe graft-versus-host disease and lower one-year survival rates than those without (p = 0.003 and p = 0.044, respectively). Interestingly, the presence of variants reduced the rate of CMV clearance, particularly in patients who did not modify their initial antiviral regimen. However, it had no apparent impact on individuals whose antiviral regimens were changed due to refractoriness. This study highlights the importance of identifying genetic variants associated with CMV drug resistance in HCT recipients for providing appropriate antiviral treatment and predicting patient outcomes.

Spotlight on the impact of viral infections on Hematopoietic Stem Cells (HSCs) with a focus on COVID-19 effects

Hematopoietic stem cells (HSCs) are known for their significant capability to reconstitute and preserve a functional hematopoietic system in long-term periods after transplantation into conditioned hosts. HSCs are thus crucial cellular targets for the continual repair of inherited hematologic, metabolic, and immunologic disorders. In addition, HSCs can undergo various fates, such as apoptosis, quiescence, migration, differentiation, and self-renewal. Viruses continuously pose a remarkable health risk and request an appropriate, balanced reaction from our immune system, which as well as affects the bone marrow (BM). Therefore, disruption of the hematopoietic system due to viral infection is essential. In addition, patients for whom the risk-to-benefit ratio of HSC transplantation (HSCT) is acceptable have seen an increase in the use of HSCT in recent years. Hematopoietic suppression, BM failure, and HSC exhaustion are all linked to chronic viral infections. Virus infections continue to be a leading cause of morbidity and mortality in HSCT recipients, despite recent advancements in the field. Furthermore, whereas COVID-19 manifests initially as an infection of the respiratory tract, it is now understood to be a systemic illness that significantly impacts the hematological system. Patients with advanced COVID-19 often have thrombocytopenia and blood hypercoagulability. In the era of COVID-19, Hematological manifestations of COVID-19 (i.e., thrombocytopenia and lymphopenia), the immune response, and HSCT may all be affected by the SARS-CoV-2 virus in various ways. Therefore, it is important to determine whether exposure to viral infections may affect HSCs used for HSCT, as this, in turn, may affect engraftment efficiency. In this article, we reviewed the features of HSCs, and the effects of viral infections on HSCs and HSCT, such as SARS-CoV-2, HIV, cytomegalovirus, Epstein-Barr virus, HIV, etc. Video Abstract.

Cost Effectiveness of Letermovir for Cytomegalovirus Prophylaxis Compared with Pre-Emptive Therapy in Allogeneic Hematopoietic Stem Cell Transplant Recipients in the United States

PURPOSE

The aim of this study was to assess the cost effectiveness of letermovir prophylaxis with the option for subsequent pre-emptive therapy (PET) for the prevention of cytomegalovirus (CMV) infection compared with a PET-only scenario in adult allogeneic hematopoietic stem cell transplant (allo-HCT) recipients in the United States over a 10-year time horizon.

MATERIALS AND METHODS

A publicly available decision tree model was constructed using a commercial third-party payer perspective to simulate an allo-HCT recipient's clinical trajectory in the first-year post-transplant, followed by entry to a Markov model to simulate years 2 through 10. Clinical inputs and utility estimates were derived from published literature. Costs were derived from published literature and US Department of Veterans Affairs Federal Supply Schedule drug pricing. Outcomes assessed included life expectancy, quality-adjusted life-years (QALYs), direct medical costs, and the incremental cost-effectiveness ratio (ICER). One-way and probabilistic sensitivity analyses (PSA) were performed to test the robustness of the findings.

RESULTS

Compared with PET alone, letermovir prophylaxis was projected to increase life-years per person (4.99 vs. 4.70 life-years), and increase QALYs (3.29 vs. 3.08) and costs (US$83.411 vs. US$70,698), yielding an ICER of US$59,356 per QALY gained. One-way sensitivity analyses indicated our model was sensitive to mortality (ICER: $164,771/QALY) and utility (letermovir ICER: $117,447/QALY; PET ICER: $107,290/QALY) in the first-year post-transplant. In 57.1% of the PSA simulations, letermovir was a cost-effective option using a willingness-to-pay threshold of US$100,000 per QALY.

CONCLUSIONS

Letermovir prophylaxis is cost effective compared with PET alone with a willingness-to-pay threshold of US$100,000 per QALY gained. Sensitivity analysis results indicate future research is required to understand the impact of mortality and quality of life in the first-year post-transplant to arrive at a conclusive decision on letermovir adoption.

How I prevent viral reactivation in high-risk patients

Preventing viral infections at an early stage is a key strategy for successfully improving transplant outcomes. Preemptive therapy and prophylaxis with antiviral agents have been successfully used to prevent clinically significant viral infections in hematopoietic cell transplant recipients. Major progress has been made over the past decades in preventing viral infections through a better understanding of the biology and risk factors, as well as the introduction of novel antiviral agents and advances in immunotherapy. High-quality evidence exists for the effective prevention of herpes simplex virus, varicella-zoster virus, and cytomegalovirus infection and disease. Few data are available on the effective prevention of human herpesvirus 6, Epstein-Barr virus, adenovirus, and BK virus infections. To highlight the spectrum of clinical practice, here we review high-risk situations that we handle with a high degree of uniformity and cases that feature differences in approaches, reflecting distinct hematopoietic cell transplant practices, such as ex vivo T-cell depletion.

Impact of GVHD prophylaxis on CMV reactivation and disease after HLA-matched peripheral blood stem cell transplantation

The kinetics of early and late cytomegalovirus (CMV) reactivation after hematopoietic cell transplantation using various methods of graft-versus-host-disease (GVHD) prophylaxis are poorly defined. We retrospectively compared CMV reactivation and disease among 780 seropositive patients given HLA-matched peripheral blood stem cell (PBSC) grafts and calcineurin inhibitor plus posttransplantation cyclophosphamide (PTCy; n = 44), mycophenolate mofetil (MMF; n = 414), or methotrexate (MTX; n = 322). Transplantation occurred between 2007 and 2018; CMV monitoring/management followed uniform standard practice. Hazards of CMV reactivation at various thresholds were compared. Spline curves were fit over average daily viral load and areas under the curve (AUC) within 1 year were calculated. PTCy and MMF were associated with an increased risk of early (day ≤100) CMV reactivation ≥250 IU/mL after multivariate adjustment. The viral load AUC at 1 year was highest with MMF (mean difference = 0.125 units vs MTX group) and similar between PTCy and MTX (mean difference = 0.016 units vs MTX group). CMV disease risk was similar across groups. There was no interaction between GVHD prophylaxis and CMV reactivation on chronic GVHD risk. Despite PTCy-associated increased risk of early CMV reactivation, the CMV disease risk by 1 year was low in HLA-matched PBSC transplant recipients. In contrast, MMF was associated with higher overall CMV viral burden in the 1 year posttransplant. Although different mechanisms of immunosuppressive agents may affect CMV reactivation risk, effective prevention of GVHD may reduce corticosteroid exposure and mitigate infection risk over time.