Pitfalls in Valganciclovir Prophylaxis Dose Adjustment Based on Renal Function in Kidney Transplant Recipients.

Valganciclovir (VGC) is administered as prophylaxis to kidney transplant recipients (KTR) CMV donor (D)+/recipient (R)- and CMV R+ after thymoglobulin-induction (R+/TG). Although VGC dose adjustments based on renal function are recommended, there is paucity of real-life data on VGC dosing and associations with clinical outcomes. This is a retrospective Swiss Transplant Cohort Study-embedded observational study, including all adult D+/R- and R+/TG KTR between 2010 and 2020, who received prophylaxis with VGC. The primary objective was to describe the proportion of inappropriately (under- or over-) dosed VGC week-entries. Secondary objectives included breakthrough clinically significant CMV infection (csCMVi) and potential associations between breakthrough-csCMVi and cytopenias with VGC dosing. Among 178 KTR, 131 (73.6%) patients had ≥2 week-entries for the longitudinal data of interest and were included in the outcome analysis, with 1,032 VGC dose week-entries. Overall, 460/1,032 (44.6%) were appropriately dosed, while 234/1,032 (22.7%) and 338/1,032 (32.8%) were under- and over-dosed, respectively. Nineteen (14.5%) patients had a breakthrough-csCMVi, without any associations identified with VCG dosing (p = 0.44). Unlike other cytopenias, a significant association between VGC overdosing and lymphopenia (OR 5.27, 95% CI 1.71-16.22, p = 0.004) was shown. VGC prophylaxis in KTR is frequently inappropriately dosed, albeit without meaningful clinical associations, neither in terms of efficacy nor safety.

Antiviral medications for preventing cytomegalovirus disease in solid organ transplant recipients.

BACKGROUND: The risk of cytomegalovirus (CMV) infection in solid organ transplant recipients has resulted in the frequent use of prophylaxis to prevent the clinical syndrome associated with CMV infection. This is an update of a review first published in 2005 and updated in 2008 and 2013. OBJECTIVES: To determine the benefits and harms of antiviral medications to prevent CMV disease and all-cause death in solid organ transplant recipients. SEARCH METHODS: We contacted the information specialist and searched the Cochrane Kidney and Transplant Register of Studies up to 5 February 2024 using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs comparing antiviral medications with placebo or no treatment, comparing different antiviral medications or different regimens of the same antiviral medications for CMV prophylaxis in recipients of any solid organ transplant. Studies examining pre-emptive therapy for CMV infection are studied in a separate review and were excluded from this review. DATA COLLECTION AND ANALYSIS: Two authors independently assessed study eligibility, risk of bias and extracted data. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS: This 2024 update found four new studies, bringing the total number of included studies to 41 (5054 participants). The risk of bias was high or unclear across most studies, with a low risk of bias for sequence generation (12), allocation concealment (12), blinding (11) and selective outcome reporting (9) in fewer studies. There is high-certainty evidence that prophylaxis with aciclovir, ganciclovir or valaciclovir compared with placebo or no treatment is more effective in preventing CMV disease (19 studies: RR 0.42, 95% CI 0.34 to 0.52), all-cause death (17 studies: RR 0.63, 95% CI 0.43 to 0.92), and CMV infection (17 studies: RR 0.61, 95% CI 0.48 to 0.77). There is moderate-certainty evidence that prophylaxis probably reduces death from CMV disease (7 studies: RR 0.26, 95% CI 0.08 to 0.78). Prophylaxis reduces the risk of herpes simplex and herpes zoster disease, bacterial and protozoal infections but probably makes little to no difference to fungal infection, acute rejection or graft loss. No apparent differences in adverse events with aciclovir, ganciclovir or valaciclovir compared with placebo or no treatment were found. There is high certainty evidence that ganciclovir, when compared with aciclovir, is more effective in preventing CMV disease (7 studies: RR 0.37, 95% CI 0.23 to 0.60). There may be little to no difference in any outcome between valganciclovir and IV ganciclovir compared with oral ganciclovir (low certainty evidence). The efficacy and adverse effects of valganciclovir or ganciclovir were probably no different to valaciclovir in three studies (moderate certainty evidence). There is moderate certainty evidence that extended duration prophylaxis probably reduces the risk of CMV disease compared with three months of therapy (2 studies: RR 0.20, 95% CI 0.12 to 0.35), with probably little to no difference in rates of adverse events. Low certainty evidence suggests that 450 mg/day valganciclovir compared with 900 mg/day valganciclovir results in little to no difference in all-cause death, CMV infection, acute rejection, and graft loss (no information on adverse events). Maribavir may increase CMV infection compared with ganciclovir (1 study: RR 1.34, 95% CI: 1.10 to 1.65; moderate certainty evidence); however, little to no difference between the two treatments were found for CMV disease, all-cause death, acute rejection, and adverse events at six months (low certainty evidence). AUTHORS' CONCLUSIONS: Prophylaxis with antiviral medications reduces CMV disease and CMV-associated death, compared with placebo or no treatment, in solid organ transplant recipients. These data support the continued routine use of antiviral prophylaxis in CMV-positive recipients and CMV-negative recipients of CMV-positive organ transplants.

Advances in pharmacotherapies for cytomegalovirus infection: what is the current state of play?

INTRODUCTION: Cytomegalovirus (CMV) remains a serious opportunistic infection in hematopoietic cell transplant (HCT) and solid-organ transplant (SOT) recipients. Traditional anti-CMV drugs are limited by toxicities and the development of resistance. Letermovir and maribavir are newly approved antivirals for the prevention and treatment of CMV. AREAS COVERED: Prior reviews have discussed use of letermovir for prevention of CMV after HCT and maribavir for resistant or refractory (R/R) CMV post HCT or SOT. Subsequent data have expanded their use including letermovir for primary CMV prophylaxis in high-risk renal transplant recipients and new recommendations for extending prophylaxis through day + 200 in certain HCT patients. Data on the use of maribavir for first asymptomatic CMV infection post-HCT has also been published. This review compares the pharmacology of anti-CMV agents and discusses the updated literature of these new drugs in the prevention and treatment of CMV. EXPERT OPINION: Letermovir and maribavir are much needed tools that spare toxicities of ganciclovir, foscarnet, and cidofovir. High cost is a challenge preventing their integration into clinical practice in resource-limited countries. Transplant centers need to exercise restraint in overuse to avoid resistance, particularly in the setting of high viral loads.

Distinct T cell responsiveness to different COVID-19 vaccines and cross-reactivity to SARS-CoV-2 variants with age and CMV status.

Introduction: Accumulating evidence indicates the importance of T cell immunity in vaccination-induced protection against severe COVID-19 disease, especially against SARS-CoV-2 Variants-of-Concern (VOCs) that more readily escape from recognition by neutralizing antibodies. However, there is limited knowledge on the T cell responses across different age groups and the impact of CMV status after primary and booster vaccination with different vaccine combinations. Moreover, it remains unclear whether age has an effect on the ability of T cells to cross-react against VOCs. Methods: Therefore, we interrogated the Spike-specific T cell responses in healthy adults of the Dutch population across different ages, whom received different vaccine types for the primary series and/or booster vaccination, using IFNÉ£ ELISpot. Cells were stimulated with overlapping peptide pools of the ancestral Spike protein and different VOCs. Results: Robust Spike-specific T cell responses were detected in the vast majority of participants upon the primary vaccination series, regardless of the vaccine type (i.e. BNT162b2, mRNA-1273, ChAdOx1 nCoV-19, or Ad26.COV2.S). Clearly, in the 70+ age group, responses were overall lower and showed more variation compared to younger age groups. Only in CMV-seropositive older adults (>70y) there was a significant inverse relation of age with T cell responses. Although T cell responses increased in all age groups after booster vaccination, Spike-specific T cell frequencies remained lower in the 70+ age group. Regardless of age or CMV status, primary mRNA-1273 vaccination followed by BNT162b2 booster vaccination showed limited booster effect compared to the BNT162b2/BNT162b2 or BNT162b2/mRNA-1273 primary-booster regimen. A modest reduction in cross-reactivity to the Alpha, Delta and Omicron BA.1, but not the Beta or Gamma variant, was observed after primary vaccination. Discussion: Together, this study shows that age, CMV status, but also the primary-booster vaccination regimen influence the height of the vaccination-induced Spike-specific T cell response, but did not impact the VOC cross-reactivity.

Handling of human milk to prevent acquired cytomegalovirus infection in Japanese neonatal intensive care units: The first nationwide survey.

BACKGROUND: Human milk (HM) has been proven to provide immunological and nutritional advantages to neonates; however, acquired cytomegalovirus (CMV) infection can be associated with raw HM. In Japan, there are no standardized guidelines concerning HM handling. This cross-sectional survey was performed to reveal specific trends in HM handling in neonatal intensive care units (NICUs) in Japan. METHODS: A questionnaire was sent to 255 NICUs participating in the Japanese Neonatologist Association in May 2020. It involved HM handling practices, such as maternal screening, pasteurization, storage, and the workforce. RESULTS: Of 255 NICUs, 174 (67.8%) responded to the survey. Maternal CMV screening was carried out in 37 units (22.2%), and CMV inactivation in HM was performed in 44 units (26.5%). For CMV inactivation, a freeze-thawing method was employed in about 90% of units. In 70% of units providing CMV inactivation, CMV inactivation was conducted regardless of bodyweight and corrected gestational age of infants until the infants' discharge. Acquired CMV infection in preterm neonates was observed in 43 units (25.7%) in the survey period. CONCLUSION: A wide range of HM handling practices are used in Japanese NICUs. A national guideline for handling HM in NICUs should be created to promote the infection control of CMV.

Valacyclovir or valganciclovir for cytomegalovirus prophylaxis: A randomized controlled trial in adult and pediatric kidney transplant recipients.

BACKGROUND: Valganciclovir (valG), a cytomegalovirus (CMV) prophylactic agent, has dose-limiting side effects. The tolerability and effectiveness of valacyclovir (valA) as CMV prophylaxis is unknown. METHODS: We conducted a randomized, open-label, single-center trial of valA versus valG for all posttransplant CMV prophylaxis in adult and pediatric kidney recipients. Participants were randomly assigned to receive valA or valG. Primary endpoints were the incidence of CMV viremia and side-effect related drug reduction with secondary assessment of incidence of EBV viremia. RESULTS: Of the 137 sequential kidney transplant recipients enrolled, 26 % were positive and negative for CMV antibody in donor and recipient respectively. The incidence of CMV viremia (4 of 71 [6 %]; 8 of 67 [12 %] P = 0.23), time to viremia (P = 0.16) and area under CMV viral load time curve (P = 0.19) were not significantly different. ValG participants were significantly more likely to require side-effect related dose reduction (15/71 [21 %] versus 1/66 [2 %] P = 0.0003). Leukopenia was the most common reason for valG dose reduction and granulocyte-colony stimulating factor was utilized for leukopenia recovery more frequently (25 % in valG vs 5 % in valA: P = 0.0007). Incidence of EBV viremia was not significantly different. CONCLUSIONS: ValA has significantly less dose-limiting side effects than valG. In our study population, a significant increase in CMV viremia was not observed, in adults and children after kidney transplant, compared to valG. TRIAL REGISTRATION NUMBER: NCT01329185.

Approaches and Challenges in the Current Management of Cytomegalovirus in Transplant Recipients: Highlighting the Role of Advanced Practice Providers (Nurse Practitioners and Physician Assistants).

Cytomegalovirus (CMV) infection is associated with increased morbidity and mortality in hematopoietic cell transplant (HCT) and solid organ transplant (SOT) recipients, with traditional anti-CMV therapies limited by their associated toxicities and the development of resistance. Clinical providers are often faced with challenging and complicated CMV infections that require multiple courses of antiviral therapies. Increasingly, advanced practice providers (APPs) are playing an important role in the day-to-day management of transplant recipients with CMV infection, including resistant/refractory CMV and other complex CMV syndromes. Here, we provide an overview of current preventative and treatment strategies for CMV infection in HCT and SOT recipients, highlighting the challenging aspects of current management and the potential utility of newer antiviral agents. This article also focuses on how a multidisciplinary team, orchestrated by APPs, can improve CMV-associated patient outcomes. Protocols using antiviral agents for the prevention or treatment of CMV infections require carefully designed and meticulously implemented strategies to ensure the best clinical outcomes for patients. APPs, who have increasingly become the frontline providers of outpatient care for transplant recipients, are ideally positioned to design and carry out these protocols.

Letermovir prophylaxis for cytomegalovirus in lung-transplant recipients: a comprehensive study with literature review of off-label use and real-world experiences.

Letermovir, initially approved for cytomegalovirus (CMV) prophylaxis in hematopoietic stem-cell transplantation, has gained attention for off-label use in lung-transplant (LTx) recipients. Given the high susceptibility of LTx recipients to CMV infection, this study explores the effectiveness and safety of letermovir prophylaxis. A retrospective analysis of using letermovir for LTx recipients at Tohoku University Hospital (January 2000 to November 2023) was conducted. Case summaries from other Japanese transplant centers and a literature review were included. Six cases at Tohoku University Hospital and one at Kyoto University Hospital were identified. Prophylactic letermovir use showed positive outcomes in managing myelosuppression and preventing CMV replication. The literature review supported the safety of letermovir in high-risk LTx recipients. Despite limited reports, our findings suggest letermovir's potential as prophylaxis for LTx recipients intolerant to valganciclovir. Safety, especially in managing myelosuppression, positions letermovir as a promising option. However, careful consideration is important in judiciously integrating letermovir into the treatment protocol.

Real-life use of letermovir prophylaxis for cytomegalovirus in heart transplant recipients.

INTRODUCTION: Cytomegalovirus (CMV) remains the predominant opportunistic infection following solid organ transplantation (SOT). While valganciclovir is the drug of choice for CMV prophylaxis, its utility can be compromised due to the risk of cytopenia. Letermovir, a novel agent approved for CMV prophylaxis in allogeneic hematopoietic stem cell transplant recipients and high-risk kidney transplant recipients, exhibits reduced toxicity. This study aims to present the practical application of letermovir as both primary and secondary prophylaxis against CMV in heart transplant recipients (HTR). METHODS: In this observational, retrospective, single-center study, we included all consecutive adult HTRs from June 2020 to January 2022 who were administered letermovir for CMV prophylaxis. We documented instances of CMV breakthrough infections, side effects related to letermovir, changes in neutropenia following the switch from valganciclovir to letermovir, and any drug interactions with the immunosuppressive regimen. RESULTS: The study comprised 10 patients: two received primary prophylaxis with letermovir due to a high risk of CMV infection (donor-positive, recipient-negative serostatus), and eight received it as secondary prophylaxis following a CMV infection. The median duration of letermovir administration was 8 months (range 3-12 months). No CMV breakthrough infections were reported while on prophylaxis. However, three patients experienced CMV breakthrough infections after discontinuing letermovir prophylaxis (30%). No significant side effects were observed, although one patient reported digestive intolerance. Among the nine patients on tacrolimus, six needed reduced doses after switching to letermovir. CONCLUSION: This real-life study appears to support the effectiveness of letermovir prophylaxis in HTR. Nonetheless, the risk of CMV infection post-treatment cessation is notable. Further drug monitoring and research on the efficacy of letermovir for CMV prophylaxis in SOT patients is warranted.

Mortality in recipients of allogeneic haematopoietic cell transplantation in the era of cytomegalovirus primary prophylaxis: a single-centre retrospective experience.

OBJECTIVES: Allogeneic haematopoietic cell transplant (allo-HCT) recipients who are cytomegalovirus (CMV)-seronegative have better post-transplant outcomes than CMV-seropositive recipients. Letermovir (LTV) is approved for CMV primary prophylaxis in adults who are CMV-seropositive after allo-HCT, and its use is associated with improved long-term post-transplant outcomes. We analysed whether LTV has affected the relationship between CMV serostatus and post-transplant outcomes. METHODS: We conducted a retrospective single-centre cohort study of allo-HCT recipients, stratified according to donor (D) and recipient (R). CMV serostatus and the use of LTV: D-/R-, R+/LTV-, and R+/LTV+. Outcomes measured were all-cause and non-relapse mortality, clinically significant CMV infection, graft-versus-host disease, and relapse up to week 48 after allo-HCT. The D-/R- group served as the reference for comparisons in univariate, competing risk regression, and cumulative incidence functions. RESULTS: The analysis included 1071 consecutive allo-HCT recipients: 131 D-/R-, 557 R+/LTV-, and 383 R+/LTV+. All-cause mortality by day 100 was 6.1% for the D-/R- group, compared with 14.0% (p 0.024) and 7.8% (p 0.7) for the R+/LTV- and R+/LTV + groups, respectively. Non-relapse mortality by day 100 was 11.0%, 6.8% and 3.8% for R+/LTV-, R+/LTV+, and D-/R- groups, respectively, without significant difference. When including relapse as a competing event, the hazard ratio for non-relapse mortality was 1.83 (95% CI: 1.12-2.99, p 0.017) for R+/LTV- compared with D-/R- and 1.05 (95% CI 0.62-1.77, p 0.85) for R+/LTV + compared with D-/R-. DISCUSSION: CMV primary prophylaxis with LTV abrogated the mortality gap based on CMV serostatus, a protective effect that persisted after discontinuation of primary prophylaxis.

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.

Cytomegalovirus Reactivations in Allogeneic Hematopoietic Stem Cell Transplantation from HLA-Matched and Haploidentical Donors with Post-Transplantation Cyclophosphamide.

Cytomegalovirus (CMV) reactivations cause significant morbidity in allogeneic hematopoietic stem cell transplantation (HSCT) recipients. Graft-versus-host disease (GVHD) prophylaxis with post-transplantation cyclophosphamide (PTCy) is associated with an increased risk of CMV infections. Data are limited comparing HSCT with PTCy performed from matched sibling donors (MSDs), matched unrelated donors (MUDs), and haploidentical (Haplo) donors. In the present study, we aimed to characterize CMV reactivation and recurrence in patients with hematologic malignancies undergoing HSCT from MSD, MUD, and Haplo donors using PTCy as GVHD prophylaxis in the pre-letermovir era. We also analyzed risk factors of CMV reactivation, including GVHD as a time-dependent variable, on the incidence and mortality associated with CMV infections. We analyzed CMV reactivation in patients undergoing HSCT from 160 MSDs, 124 MUDs, and 82 Haplo donors from a single institution. Uniform GVHD prophylaxis with PTCy, sirolimus, and mycophenolate mofetil was given irrespective of donor type. Overall, 46% of patients had at least 1 CMV reactivation. The 1-year cumulative incidence of CMV infection was 39% for MSD, 44% for MUD, and 62% for Haplo donors (P < .001), with 96% of reactivations occurring before day +100. Multivariate analysis identified factors associated with the first CMV reactivation, including Haplo donor, positive recipient CMV serology, older patient age, and grade II-IV acute GVHD. The 1-year cumulative incidence of second reactivation from HSCT was 13%. Recipient CMV seropositivity, older patient age, and grade II-IV acute GVHD, but not type of donor, were identified as adverse factors for second CMV reactivation in multivariate analysis. The 1-year cumulative incidence of a third reactivation post HSCT was 4.4%. Ten cases of CMV disease were recorded, with no attributable deaths. Nevertheless, the risk for nonrelapse mortality was greater for patients who experienced CMV reactivation in multivariate time-dependent Cox model analysis. CMV reactivation is frequent in HSCT with PTCy in patients not receiving letermovir prophylaxis. Identified risk factors include the use of a Haplo donor, recipient CMV seropositivity, and grade II-IV acute GVHD. The prevalence of recurrent CMV reactivations is a noteworthy issue, especially after acute GVHD, warranting trials of secondary prophylaxis strategies.

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.

Cytomegalovirus infection during pregnancy: cross-sectional survey of knowledge and prevention practices of healthcare professionals in French-speaking Switzerland.

BACKGROUND: Lack of Cytomegalovirus (CMV) knowledge among healthcare professionals has been proven to be the main threat to pregnant women's awareness, preventing them from reducing the risk of infection. The aims of this study were to assess the knowledge and practices of French-speaking Swiss perinatal professionals in terms of CMV prevention, as well as the sociodemographic-professional factors that influence them. METHODS: This observational study used a cross-sectional design to collect data-via an anonymous electronic questionnaire in French distributed to gynecologists-obstetricians, general practitioners and midwives via various channels: e-mails and social networks of partner centers, professional associations, and conferences. The 41-item questionnaire collected data on sociodemographic and professional characteristics, general CMV knowledge, national recommendation knowledge and prevention practices. Univariable and multivariable analyses were performed. RESULTS: A total of 110 gynecologist-obstetricians, 5 general practitioners and 226 midwives participated in the study. While more than 80% of practitioners were familiar with protective hygiene measures, significant gaps were highlighted concerning the transmission routes, as well as the signs of short- and long-term congenital CMV infection. Regarding practice, 63.3% of participants provided information on CMV to their patients, mainly during the first antenatal visit. Among those who did not, lack of knowledge and forgetfulness were the two main reasons cited. Concerning systematic screening, 45.7% of participants offered it to their patients, and 37.3% only offered it to "at risk" groups. The existence of national guidelines on CMV was known by 62.0% of participants. Multivariable analysis revealed that working as a gynecologist-obstetrician was independently associated with higher score of preventive practices, while performing ultrasound or preconception consultations was independently associated with a higher score of general CMV knowledge, and working in a university hospital was independently associated with a higher score of Swiss recommendation knowledge. A level of training higher than the basic medical or midwifery diploma and participation in fetal medicine symposia both promote a higher score of CMV knowledge and prevention practices in line with current recommendations. CONCLUSION: This study confirms the significant gaps in CMV knowledge among French-speaking Swiss caregivers along with the heterogeneity of their prevention practices. To raise awareness among pregnant women and reduce the burden of congenital CMV infections, improving professional knowledge through access to specific training and standardizing practices should be a national priority.

Antiviral activity of immunosuppressors alone and in combination against human adenovirus and cytomegalovirus.

Human adenovirus (HAdV) and cytomegalovirus (HCMV) cause high morbidity and mortality in patients undergoing solid organ transplantation (SOT) and haematopoietic stem cell transplantation (HSCT). Immunosuppressors are used universally to prevent graft-vs-host disease in HSCT and graft rejection in SOT. The long-term use of these drugs is associated with a high risk of infection, but there is also evidence of their specific interference with viral infection. This study evaluated the antiviral activity of immunosuppressors commonly used in clinical practice in SOT and HSCT recipients in vitro to determine whether their use could be associated with reduced risk of HAdV and HCMV infection. Cyclophosphamide, tacrolimus, cyclosporine, mycophenolic acid, methotrexate, everolimus and sirolimus presented antiviral activity, with 50% inhibitory concentration (IC50) values at low micromolar and sub-micromolar concentrations. Mycophenolic acid and methotrexate showed the greatest antiviral effects against HAdV (IC50=0.05 µM and 0.3 µM, respectively) and HCMV (IC50=10.8 µM and 0.02 µM, respectively). The combination of tacrolimus and mycophenolic acid showed strong synergistic antiviral activity against both viruses, with combinatory indexes (CI50) of 0.02 and 0.25, respectively. Additionally, mycophenolic acid plus cyclosporine, and mycophenolic acid plus everolimus/sirolimus showed synergistic antiviral activity against HAdV (CI50=0.05 and 0.09, respectively), while methotrexate plus cyclosporine showed synergistic antiviral activity against HCMV (CI50=0.29). These results, showing antiviral activity in vitro against both HAdV and HCMV, at concentrations below the human Cmax values, may be relevant for the selection of specific immunosuppressant therapies in patients at risk of HAdV and HCMV infections.

The changing landscape of infections in the lung transplant recipient.

PURPOSE OF REVIEW: Infections in lung transplant recipients remain a major challenge and can affect lung allograft function and cause significant morbidity and mortality. New strategies for the prevention and treatment of infection in lung transplantation have emerged and are reviewed. RECENT FINDINGS: For important vaccine preventable infections (VPIs), guidance has been updated for at risk solid organ transplant (SOT) recipients. However, data on the efficacy of newer vaccines in lung transplant, including the respiratory syncytial virus (RSV) vaccine, are limited. Studies demonstrate improved vaccination rate with Infectious Diseases consultation during pretransplant evaluation. Two new antiviral agents for the treatment and prevention of cytomegalovirus (CMV) in SOT, letermovir and maribavir, are being incorporated into clinical care. CMV-specific cell-mediated immune function assays are more widely available. Antibiotics for the management of multidrug resistant pathogens and Burkholderia cepacia complex have been described in case series and case reports in lung transplant. SUMMARY: Although new vaccines and novel therapies for preventing and treating infections are available, larger studies evaluating efficacy in lung transplant recipients are needed.

Evaluation of valganciclovir's neutropenia risk in pediatric solid organ transplant recipients utilizing two dosing regimens.

BACKGROUND: Valganciclovir is approved for cytomegalovirus prophylaxis in pediatrics using the Pescovitz algorithm. There are reports of valganciclovir overdoses in children with low body surface area and overestimated creatinine clearance utilizing this algorithm. This study compared the incidence of neutropenia and cytomegalovirus infection between the Pescovitz and weight-based dosing algorithms. METHODS: A single-center retrospective chart review from January 2010 to September 2018 was performed on pediatric heart, liver, and kidney transplant recipients, who received valganciclovir. Data were collected from the initiation of valganciclovir prophylaxis to 30 days after discontinuation. The primary objective was the incidence of neutropenia in patients receiving valganciclovir dosed by the Pescovitz versus weight-based dosing algorithms. RESULTS: This study included 187 pediatric transplant recipients who received valganciclovir dosed via the Pescovitz (62 recipients) or weight-based dosing algorithms (125 recipients). The incidence of neutropenia was higher in the Pescovitz (69.4%) compared to the weight-based dosing group (53.6%; p = .04) including moderate and severe neutropenia. Cytomegalovirus viremia was not significantly different between the two groups and occurred in 4.8% of the Pescovitz group compared to 2.4% of the weight-based group (p = .4). CONCLUSIONS: The incidence of neutropenia was greater in recipients receiving valganciclovir dosed via the Pescovitz algorithm compared to the weight-based dosing. There were no significant differences in regard to cytomegalovirus viremia or disease between the two groups.

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.