Long-term acyclovir for prevention of varicella zoster virus disease after allogeneic hematopoietic cell transplantation--a randomized double-blind placebo-controlled study

Efficacy, Safety, and Cost-effectiveness Analysis of Antiviral Agents for Cytomegalovirus Prophylaxis in Allogeneic Hematopoietic Stem Cell Transplantation Recipients

BACKGROUND

Cytomegalovirus (CMV) infection is associated with higher non-relapse mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). But the preferred drug for preventing cytomegalovirus infection is still controversial. We evaluate the efficacy, safety, and cost-effectiveness of antiviral agents based on the most recent studies.

METHODS

A pairwise and network meta-analysis was conducted to obtain direct and indirect evidence of antivirals. The cost of allo-HSCT recipients in a teaching hospital was collected, and a cost-effectiveness analysis using a decision tree combined with Markov model was completed from the perspective of allo-HSCT recipients over a lifetime horizon.

RESULTS

A total of 19 RCTs involving 3565 patients (8 antivirals) were included. In the network meta-analysis, relative to placebo, letermovir, valacyclovir, and ganciclovir significantly reduced CMV infection incidence; ganciclovir significantly reduced CMV disease incidence; ganciclovir significantly increased the incidence of serious adverse event; none of antivirals significantly reduced all-cause mortality. Based on meta-analysis and Chinese medical data, the incremental cost-effectiveness ratios (ICER) per quality-adjusted life year (QALY) saved for maribavir, acyclovir, valacyclovir, ganciclovir, and letermovir relative to placebo corresponded to US$216 635.70, US$11 590.20, US$11 816.40, US$13 049.90, and US$12 189.40, respectively. One-way sensitivity analysis showed the most influential parameter was discount rate. The probabilistic sensitivity analysis indicated a 53.0% probability of letermovir producing an ICER below the willingness-to-pay threshold of US$38 824.23/QALY. The scenario analysis demonstrated prophylaxis with letermovir is considered cost-effective in the United States.

CONCLUSIONS

Currently, letermovir is an effective and well-tolerated treatment for preventing CMV infection, and it might be a cost-effective choice in allo-HSCT recipients in China.

A predictive model of herpes zoster after allogeneic hematopoietic stem cell transplantation: VZV reactivation following antiviral prophylaxis discontinuation

Herpes zoster (HZ) refers to the rash appearing on dermatomes due to varicella zoster virus (VZV) reactivation. The incidence of HZ is significantly higher in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients than in non-HSCT recipients. Although acyclovir prophylaxis is routinely administered to every allo-HSCT recipient for 1 year after transplantation, some individuals eventually develop late-onset HZ after completing prophylaxis. Little information is known about the clinical features of HZ after prophylactic antiviral treatment discontinuation, and an effective predictive model of late-onset HZ needs to be established. A total of 3366 patients who had received allo-HSCT from 2012 to 2017 were included in our study, among whom 201 developed HZ after 1 year (late-onset HZ). We designed a nested case-control study to identify potential predictors of late-onset HZ. Finally, we established a predictive model using binary logistic regression analysis. Age (p < .001), use of immunosuppressants at +1 year (p < .001), CD4-CD8 ratio at +1 year (p < .001), certain mental disorders (depression, anxiety, insomnia and adjustment disorder) (p < .001), engraftment time of neutrophils (p < .001), and CD8+ cell count at +30 days (p < .001) were independent predictors of late-onset HZ. A risk grading system was established based on regression coefficients. Discrimination and calibration analysis indicated that the model had good performance. We also identified several predictive factors of the incidence of HZ-related complications. This is the first scoring system for predicting the incidence of late-onset HZ after allo-HSCT. This model can be applied to identify individuals at high risk of late-onset HZ in the early period after receiving allo-HSCT.

Herpes Virus Infection in Lung Transplantation: Diagnosis, Treatment and Prevention Strategies

Lung transplantation is an ultimate treatment option for some end-stage lung diseases; due to the intense immunosuppression needed to reduce the risk of developing acute and chronic allograft failure, infectious complications are highly incident. Viral infections represent nearly 30% of all infectious complications, with herpes viruses playing an important role in the development of acute and chronic diseases. Among them, cytomegalovirus (CMV) is a major cause of morbidity and mortality, being associated with an increased risk of chronic lung allograft failure. Epstein-Barr virus (EBV) is associated with transformation of infected B cells with the development of post-transplantation lymphoproliferative disorders (PTLDs). Similarly, herpes simplex virus (HSV), varicella zoster virus and human herpesviruses 6 and 7 can also be responsible for acute manifestations in lung transplant patients. During these last years, new, highly sensitive and specific diagnostic tests have been developed, and preventive and prophylactic strategies have been studied aiming to reduce and prevent the incidence of these viral infections. In this narrative review, we explore epidemiology, diagnosis and treatment options for more frequent herpes virus infections in lung transplant patients.

High pesticide exposures events, pesticide poisoning, and shingles: A medicare-linked study of pesticide applicators in the agricultural health study

OBJECTIVES

Self-reported shingles was associated with history of high pesticide exposure events (HPEE) in licensed pesticide applicators aged >60 years in the Agricultural Health Study (AHS). In the current study, using AHS-linked Medicare claims data, we examined incident shingles in relation to pesticide-related illness and pesticide poisoning, as well as HPEE.

METHODS

We studied 22,753 licensed private pesticide applicators (97% white males, enrolled in the AHS 1993-97), aged ≥66 years with >12 consecutive months of Medicare fee-for-service hospital and outpatient coverage between 1999 and 2016. Incident shingles was identified based on having ≥1 shingles claim(s) after 12 months without claims. At AHS enrollment, participants were asked if they ever sought medical care or were hospitalized for pesticide-related illness, and a supplemental questionnaire (completed by 51%) asked about HPEE and poisoning. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional hazards regression, adjusted for age, sex, race, state, and education.

RESULTS

Over 192,053 person-years (PY), 2396 applicators were diagnosed with shingles (10.5%; age-standardized rate, 13.6 cases per 1,000PY), with higher rates among those reporting hospitalization for pesticide-related illness, pesticide poisoning, and HPEE (23.2, 22.5, and 16.6 per 1,000PY, respectively). In adjusted models, shingles was associated with hospitalization for pesticide-related illness (HR 1.69; 1.18, 2.39), poisoning (1.49; 1.08, 1.46), and HPEE (1.23; 95% CI = 1.03, 1.46), especially HPEE plus medical care/poisoning (1.78; 1.30, 2.43).

CONCLUSION

These novel findings suggest that acute, high-level, and clinically impactful pesticide exposures may increase risk of shingles in subsequent years to decades following exposure.

Hematopoietic stem cell transplantation and the noncytomegalovirus herpesviruses

Although hematopoietic stem cell transplantation (HSCT) and other cellular therapies have significantly improved outcomes in the management of multiple hematological and nonhematological malignancies, the resulting impairment in humoral and cellular response increases the risk for opportunistic infection as an undesirable side effect. With their ability to establish latent infection and reactivate when the host immune system is at its weakest point, the Herpesviridae family constitutes a significant proportion of these opportunistic pathogens. Despite recent advancements in preventing and managing herpesvirus infections, they continue to be a common cause of significant morbidity and mortality in transplanted patients. Herein, we aim to provide and update on herpesvirus other than cytomegalovirus (CMV) affecting recipients of HSCT and other cellular therapies.

Acute graft-versus-host disease

Acute graft-versus-host disease (GVHD) is a common immune complication that can occur after allogeneic haematopoietic cell transplantation (alloHCT). Acute GVHD is a major health problem in these patients, and is associated with high morbidity and mortality. Acute GVHD is caused by the recognition and the destruction of the recipient tissues and organs by the donor immune effector cells. This condition usually occurs within the first 3 months after alloHCT, but later onset is possible. Targeted organs include the skin, the lower and upper gastrointestinal tract and the liver. Diagnosis is mainly based on clinical examination, and complementary examinations are performed to exclude differential diagnoses. Preventive treatment for acute GVHD is administered to all patients who receive alloHCT, although it is not always effective. Steroids are used for first-line treatment, and the Janus kinase 2 (JAK2) inhibitor ruxolitinib is second-line treatment. No validated treatments are available for acute GVHD that is refractory to steroids and ruxolitinib, and therefore it remains an unmet medical need.

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.

Cell and Tissue Specific Metabolism of Nucleoside and Nucleotide Drugs: Case Studies and Implications for Precision Medicine

Many clinically used antiviral drugs are nucleoside or nucleotide analog drugs, which have a unique mechanism of action that requires intracellular phosphorylation. This dependence on intracellular activation presents novel challenges for the discovery and development of nucleoside/nucleotide analog drugs. Contrary to many small molecule drug development programs that rely on plasma pharmacokinetics and systemic exposures, the precise mechanisms that result in efficacious intracellular nucleoside triphosphate concentrations must be understood in the process of nucleoside/nucleotide drug development. The importance is highlighted here, using the following as case studies: the herpes treatment acyclovir, the cytomegalovirus therapy ganciclovir, and human immunodeficiency virus (HIV) treatments based on tenofovir, which are also in use for HIV prophylaxis. For each drug, the specificity of metabolism that results in its activation in different cells or tissues is discussed, and the implications explored. Acyclovir's dependence on a viral enzyme for activation provides selective pressure for resistance mutations. Ganciclovir is also dependent on a viral enzyme for activation, and suicide gene therapy capitalizes on that for a novel oncology treatment. The tissue of most relevance for tenofovir activation depends on its use as treatment or as prophylaxis, and the pharmacogenomics and drug-drug interactions in those tissues must be considered. Finally, differential metabolism of different tenofovir prodrugs and its effects on toxicity risk are explored. Taken together, these examples highlight the importance of understanding tissue specific metabolism for optimal use of nucleoside/nucleotide drugs in the clinic. SIGNIFICANCE STATEMENT: Nucleoside and nucleotide analogue drugs are cornerstones in current antiviral therapy and prevention efforts that require intracellular phosphorylation for activity. Understanding their cell and tissue specific metabolism enables their rational, precision use for maximum efficacy.

Herpes Simplex Virus and Varicella Zoster Virus Infections in Cancer Patients

Herpes simplex virus (HSV) and varicella zoster virus (VZV) are alpha herpesviruses that establish life-long latent infection in neuronal ganglia after primary infection. Periodic reactivation of these viruses results in recurrent infections that can have significant impact on patients' quality of life. HSV commonly causes oral and genital mucocutaneous infections whereas VZV is responsible for varicella/chickenpox and herpes zoster/shingles, but cancer patients are at particularly higher risk of complications including disseminated and visceral infections due to impaired cell-mediated immunity. While diagnosis of more common HSV and/or VZV infections is frequently clinically based, immunocompromised hosts may have atypical skin presentation or visceral involvement. Thus, diagnostic confirmation using virus-specific tests such as polymerase chain reaction or immunohistochemical staining is crucial in some cases. Oral acyclovir, valacyclovir and famciclovir are usually used for mild to moderate infections and intravenous acyclovir is the drug of choice for severe or disseminated infections. Foscarnet can be used when acyclovir-resistance is confirmed or suspected. Pharmaceutical prophylaxis against HSV and/or VZV should be considered in high-risk cancers patients. Currently, there is no commercially available vaccine against HSV, but VZV vaccines are available to prevent varicella and zoster.

Risk stratification system for skin and soft tissue infections after allogeneic hematopoietic stem cell transplantation: PAH risk score

Skin and soft tissue infections (SSTIs) refer to infections involving the skin, subcutaneous tissue, fascia, and muscle. In transplant populations with hematological malignancies, an immunocompromised status and the routine use of immunosuppressants increase the risk of SSTIs greatly. However, to date, the profiles and clinical outcomes of SSTIs in hematopoietic stem cell transplantation (HSCT) patients remain unclear. This study included 228 patients (3.67%) who developed SSTIs within 180 days after allogeneic HSCT from January 2004 to December 2019 in Peking University People's Hospital. The overall annual survival rate was 71.5%. We compared the differences between survivors and non-survivors a year after transplant and found that primary platelet graft failure (PPGF), comorbidities of acute kidney injury (AKI), and hospital-acquired pneumonia (HAP) were independent risk factors for death in the study population. A PPGF-AKI-HAP risk stratification system was established with a mortality risk score of 1×PPGF+1×AKI+1×HAP. The areas under the curves of internal and external validation were 0.833 (95% CI 0.760-0.906) and 0.826 (95% CI 0.715-0.937), respectively. The calibration plot revealed the high consistency of the estimated risks, and decision curve analysis showed considerable net benefits for patients.

Low-dose acyclovir for prophylaxis of varicella-zoster virus reactivation after hematopoietic stem cell transplantation in children

BACKGROUND

Varicella-zoster virus (VZV) reactivation is a serious complication of hematopoietic stem cell transplantation (HSCT). Although low-dose acyclovir can prevent VZV reactivation after HSCT in adults, the efficacy of a dose of acyclovir lower than the recommended dose, such as 60-80 mg/kg/day in children, is unclear. In this study, we aimed to evaluate the incidence of VZV reactivation after HSCT during and after low-dose acyclovir administration for preventing VZV reactivation in children.

METHODS

This single-center retrospective study included children aged ≤15 years who received oral acyclovir (at 15 mg/kg/day) to prevent VZV reactivation after HSCT. We examined the cumulative incidence of VZV reactivation after HSCT, during and after prophylactic acyclovir administration.

RESULTS

Fifty-three eligible patients were included in this study, of whom 37 underwent allogeneic HSCT. The median duration of prophylactic acyclovir therapy was 264 days (range: 69-1140 days). VZV reactivation occurred in 13 patients (24.5%, 95% confidence interval [CI]: 14.9-37.6). The cumulative incidence of VZV reactivation 1 and 2 years after HSCT was 6.26% (95% CI: 1.60-15.5) and 20.9% (95% CI: 10.3-34.0), respectively. While only one patient developed VZV reactivation during the administration of prophylactic acyclovir, the cumulative incidence of VZV reactivation increased to 24.2% (95% CI: 12.5-38.0) 1 year after the cessation of acyclovir.

CONCLUSION

Low-dose acyclovir (15 mg/kg/day) could be effective for preventing VZV reactivation after HSCT in children because VZV reactivation seldom occurs during the administration of 15 mg/kg/day acyclovir.

Assessing and restoring adaptive immunity to HSV, VZV, and HHV-6 in solid organ and hematopoietic cell transplant recipients

BACKGROUND

Herpes simplex virus (HSV) 1 and 2, varicella zoster virus (VZV), and human herpesvirus 6 (HHV-6) cause severe infections in immunocompromised hosts. Interventions to optimize virus-specific adaptive immunity may have advantages over antivirals in the prophylaxis and treatment of these infections.

OBJECTIVES

We sought to review adaptive immune responses and methods for assessing and replenishing cellular and humoral immunity to HSV, VZV, and HHV-6 in solid organ transplant and hematopoietic cell transplant recipients.

SOURCES

We searched PubMed for relevant studies on immune responses to HSV, VZV, and HHV-6 as well as studies describing methods for evaluating and restoring cell-mediated immunity to other double-stranded DNA viruses in transplant recipients. Recent studies, randomized controlled trials, and investigations highlighting key concepts in clinical virology were prioritized for inclusion.

CONTENT

We describe the mechanisms of adaptive immunity to HSV, VZV, and HHV-6 and limitations of antivirals as prophylaxis and treatment for these infections in solid organ transplant and hematopoietic cell transplant recipients. We review methods for measuring and restoring cellular immunity to double-stranded DNA viruses; their potential applications to management of HSV, VZV, and HHV-6 in immunocompromised hosts; and barriers to clinical use. Vaccination and virus-specific T cell therapies are discussed in detail.

IMPLICATIONS

The growing repertoire of diagnostic and therapeutic techniques focused on virus-specific adaptive immunity provides a novel approach to management of viral infections in transplant recipients. Investigations to optimize such interventions specifically in HSV, VZV, and HHV-6 are needed.

Immunocompromised host section: Adoptive T-cell therapy for dsDNA viruses in allogeneic hematopoietic cell transplant recipients

PURPOSE OF REVIEW

Double-stranded DNA (dsDNA) viruses remain important causes of morbidity and mortality after allogeneic hematopoietic cell transplantation (HCT). As treatment options are limited, adoptive therapy with virus-specific T cells (VST) is promising in restoring immunity and thereby preventing and treating virus infections. Here we review current evidence and recent advances in the field of VST for dsDNA viruses in allogeneic HCT recipients.

RECENT FINDINGS

Four different protocols for VST generation are currently used in clinical trials, and various products including multivirus-specific and off-the-shelf products are under investigation for prophylaxis, preemptive therapy or treatment. Data from nearly 1400 dsDNA-VST applications in allogeneic HCT patients have been published and demonstrated its safety. Although Epstein-Barr virus, cytomegalovirus, and adenovirus-specific T-cell therapy studies have predominated over the past 25 years, additional human herpes viruses were added to multivirus-specific T cells over the last decade and clinical evidence for polyomavirus-specific VST has just recently emerged. Response rates of around 70-80% have been reported, but cautious interpretation is warranted as data are predominantly from phase 1/2 studies and clinical efficacy needs to be confirmed in phase 3 studies.

SUMMARY

Investigation on the 'ideal' composition of VST is ongoing. Several products recently entered phase 3 trials and may allow widespread clinical use in the near future.

Adjuvanted recombinant zoster vaccine in solid organ transplant and hematopoietic stem-cell transplant recipients

PURPOSE OF REVIEW

Hematopoietic stem-cell (HSCT) and solid organ transplant (SOT) recipients are particularly at risk to develop herpes zoster and its complications. A recently approved nonlive, adjuvanted recombinant zoster vaccine (aRZV) is a potential candidate to provide durable prevention of herpes zoster. This review summarizes current scientific evidence and expert recommendations for its use in these populations and offers practical clinical guidance.

RECENT FINDINGS

Recent clinical trials have shown aRZV to be well tolerated and efficacious in the prevention of herpes zoster, even in the elderly. Data are emerging that this vaccine might also be effective in immunocompromised individuals, such as SOT and HSCT recipients. Evidence is sparse regarding optimal timing of vaccination and durability of responses. However, several specialized societies have already established expert-based aRZV immunization recommendations for these vulnerable populations.

SUMMARY

Practical considerations, safety concerns, and timing of vaccine administration vary from one immunocompromised subpopulation to another. Initial studies show that aRZV has a favorable safety and immunogenicity profile in SOT and HSCT recipients. However, data are sparse, particularly in allogeneic HSCT, and practical recommendations are mostly based on expert opinion. Additional research is needed to offer better insight on aRZV administration in immunocompromised patients.

A Simple-to-Perform ifn-γ mRNA Gene Expression Assay on Whole Blood Accurately Appraises Varicella Zoster Virus-Specific Cell-Mediated Immunity After Allogeneic Hematopoietic Stem Cell Transplantation

Herpes zoster, which is due to the reactivation of Varicella zoster virus (VZV), is a leading cause of morbidity after allogeneic hematopoietic stem cell transplantation (allo-HSCT). While cell-mediated immunity (CMI) is critical to inhibiting VZV reactivation, CMI is not routinely assessed due to a lack of reliable tests. In this study, we aimed to evaluate VZV-specific CMI among allo-HSCT recipients (n = 60) and healthy individuals (HI, n = 17) through a panel of three immune functional assays after ex vivo stimulation by VZV antigen: quantification of (i) IFN-γ release in the supernatants, (ii) T-cell proliferation after a 7-day stimulation of peripheral blood mononuclear cells (PBMC), and (iii) measurement of the ifn-γ mRNA gene expression level after 24 h of stimulation of a whole-blood sample. VZV responsiveness was defined according to IFN-γ release from VZV-stimulated PBMC. Upon VZV stimulation, we found that allo-HSCT recipients at a median time of 6 [5-8] months post-transplant had lower IFN-γ release (median [IQR], 0.34 [0.12–8.56] vs. 409.5 [143.9–910.2] pg/ml, P <.0001) and fewer proliferating T cells (0.05 [0.01–0.57] % vs. 8.74 [3.12–15.05] %, P <.0001) than HI. A subset of allo-HSCT recipients (VZV-responders, n = 15/57, 26%) distinguished themselves from VZV-non-responders (n = 42/57, 74%; missing data, n = 3) by higher IFN-γ release (80.45 [54.3–312.8] vs. 0.22 [0.12–0.42] pg/ml, P <.0001) and T-cell proliferation (2.22 [1.18–7.56] % vs. 0.002 [0.001–0.11] %, P <.0001), suggesting recovery of VZV-specific CMI. Interestingly, VZV responders had a significant fold increase in ifn-γ gene expression, whereas ifn-γ mRNA was not detected in whole blood of VZV-non-responders (P <.0001). This study is the first to suggest that measurement of ifn-γ gene expression in 24-h-stimulated whole blood could be an accurate test of VZV-specific CMI. The routine use of this immune functional assay to guide antiviral prophylaxis at an individual level remains to be evaluated.

Viral infection in hematopoietic stem cell transplantation: an International Society for Cell & Gene Therapy Stem Cell Engineering Committee review on the role of cellular therapy in prevention and treatment

Despite recent advances in the field of HSCT, viral infections remain a frequent causeof morbidity and mortality among HSCT recipients. Adoptive transfer of viral specific T cells has been successfully used both as prophylaxis and treatment of viral infections in immunocompromised HSCT recipients. Increasingly, precise risk stratification of HSCT recipients with infectious complications should incorporate not only pretransplant clinical criteria, but milestones of immune reconstitution as well. These factors can better identify those at highest risk of morbidity and mortality and identify a population of HSCT recipients in whom adoptive therapy with viral specific T cells should be considered for either prophylaxis or second line treatment early after inadequate response to first line antiviral therapy. Broadening these approaches to improve outcomes for transplant recipients in countries with limited resources is a major challenge. While the principles of risk stratification can be applied, early detection of viral reactivation as well as treatment is challenging in regions where commercial PCR assays and antiviral agents are not readily available.

Long-term incidence of varicella zoster virus disease in adults receiving single-unit cord blood transplantation

BACKGROUND

Varicella zoster virus (VZV) disease is a common complication after allogeneic hematopoietic cell transplantation (HCT). However, research into the long-term incidence of VZV disease in adults receiving cord blood transplantation (CBT) has been limited.

OBJECTIVE

The objective of this study was to evaluate the incidence, risk factors, and clinical impact of VZV disease after CBT with a long-term follow-up in our institute.

STUDY DESIGN

We retrospectively analyzed the data for 156 adult patients who received single-unit CBT at our institute between 2007 and 2020, who achieved neutrophil engraftment and survived at least 100 days without recurrence of the underlying disease.

RESULTS

VZV disease occurred in 61 patients at a median of 608 days (range, 36 - 4090 days) after CBT. The cumulative incidence of VZV disease was 14% (95% confidence interval [CI], 9% to 20%) at 1 year and 40% (95% CI, 31% to 48%) at 5 years after CBT. Multivariate analysis showed that the cessation of antiviral prophylaxis was an independent risk factor for a higher risk of VZV disease (hazard ratio: 15.65, 95% CI: 6.59-37.21, P<0.001). The cumulative incidence of VZV disease was significantly lower in the long-term antiviral prophylaxis group given for around 1 year after CBT or the end of immunosuppressive therapy compared to the short-term antiviral prophylaxis group given for 35 days after CBT (P=0.005). Among patients who developed VZV disease, the median onset of VZV disease was significantly delayed in the long-term antiviral prophylaxis group compared to the short-term antiviral prophylaxis group (694 days vs 130 days, P<0.001), but the median onset of VZV disease after the cessation of antiviral prophylaxis was not significantly different between long-term and short-term antiviral prophylaxis (166 days vs 95 days, P=0.087).

CONCLUSION

These data demonstrated that the long-term incidence of VZV disease was relatively high in adult patients receiving CBT. Given that the incidence of VZV disease after the cessation of antiviral prophylaxis remained high, additional interventions, such as recombinant zoster vaccine administration, could be required to prevent VZV disease in long-term adult survivors after CBT.

Association between Antiviral Prophylaxis and Cytomegalovirus and Epstein-Barr Virus DNAemia in Pediatric Recipients of Allogeneic Hematopoietic Stem Cell Transplant

Background: Epstein–Barr virus (EBV) and cytomegalovirus (CMV) infections can have serious consequences during the period of aplasia and lymphopenia following hematopoietic stem cell transplantation (HSCT). Large pediatric cohort studies examining the effect of antiviral prophylaxis against these viruses are scarce. The present study aimed to analyse the potential effect of antiviral prophylaxis (acyclovir and famciclovir) on active post-transplant EBV and CMV infection in a pediatric cohort of allogeneic HSCT recipients. Methods: We used data from the TREASuRE cohort, consisting of 156 patients who had a first allogeneic HSCT, enrolled in four pediatric centers in Canada between July 2013 and March 2017. Follow-up was performed from the time of transplant up to 100 days post-transplant. Adjusted hazard ratio (HR) with 95% confidence intervals (CI) for the association between antiviral prophylaxis with acyclovir and/or famciclovir and EBV and CMV DNAemia was estimated using multivariate Cox regression models. Results: The post-transplant cumulative incidence of EBV and CMV DNAemia at 100 days of follow-up were, respectively, 34.5% (95% CI: 27.6–42.6) and 19.9% (95% CI: 14.5–27.1). For acyclovir, the adjusted hazard ratio (HR) for CMV and EBV DNAemia was 0.55 (95% CI: 0.24–1.26) and 1.41 (95% CI: 0.63–3.14), respectively. For famciclovir, the adjusted HR were 0.82 (95% CI: 0.30–2.29) and 0.79 (95% CI: 0.36–1.72) for CMV and EBV DNAemia, respectively. Conclusion: The antivirals famciclovir and acyclovir did not reduce the risk of post-transplant CMV and EBV DNAemia among HSCT recipients in our pediatric population.

Safety and reactogenicity of the recombinant zoster vaccine after allogeneic hematopoietic cell transplantation

Allogeneic hematopoietic cell transplantation (HCT) recipients are at increased risk for varicella zoster virus (VZV) reactivation and associated complications. A nonlive adjuvanted recombinant zoster vaccine (RZV) has been developed to prevent herpes zoster (HZ), but there are no recommendations for use in this population. In this single-center prospective observational cohort study, we assessed the safety and reactogenicity of RZV, as well as incidence of graft-versus-host disease (GVHD) and confirmed cases of HZ after vaccination. Between December of 2018 and June of 2020, patients aged ≥18 years received 2 doses of RZV between 9 and 24 months after HCT, with the doses separated by ≥8 weeks. One hundred and fifty-eight patients (mean age, 55 years; 42% women) received ≥1 dose (total vaccinated cohort), and 150 patients (95%) received 2 doses (modified total vaccinated cohort). Solicited reactions occurred in 92.1% of patients (grade 3, 32.5%), owing mostly to injection site pain, which occurred in 86% (grade 3, 16%). The cumulative incidence of GVHD in the peri-vaccination period was no different than in historical controls (adjusted incidence rate ratio, 1.05; 95% confidence interval, 0.8-1.38). There were 4 cases of HZ in the total vaccinated cohort (2.5%) and 3 cases in the modified total vaccinated cohort (28.3/1000 person-years). Among recipients of allogeneic HCT, RZV was safe, tolerable, and did not increase rates of GVHD. Future clinical trials are needed to determine the immunogenicity and efficacy of RZV in this population.

High Incidence of Herpes Zoster After Cord Blood Hematopoietic Cell Transplant Despite Longer Duration of Antiviral Prophylaxis

BACKGROUND

Cord blood transplant (CBT) recipients have a high incidence of herpes zoster (HZ) in the context of short-term peritransplant antiviral prophylaxis. In 2009, international guidelines recommended HZ prophylaxis for at least 1 year after hematopoietic cell transplant. The impact of longer-term antiviral prophylaxis on HZ incidence after CBT is unknown.

METHODS

We retrospectively analyzed varicella zoster virus (VZV)-seropositive CBT recipients who were transplanted between 2006 and 2016. We abstracted HZ events and other variables for up to 5 years post-CBT. We calculated the cumulative incidence of HZ and used Cox proportional hazards regression to identify variables associated with HZ.

RESULTS

The study cohort consisted of 227 patients. Among 1-year survivors, 91% were still receiving prophylaxis, for a median duration of 20.6 months. HZ occurred in 44 patients (19%) at a median of 23.6 months. The cumulative incidence of HZ by 1 year after CBT was 1.8% (95% confidence interval [CI], .1%-4%), but increased to 26% (95% CI, 19%-33%) by 5 years. In a multivariable analysis, acute graft-vs-host disease was associated with increased risk, whereas antiviral prophylaxis was associated with reduced risk for HZ (adjusted hazard ratio, 0.19 [95% CI, .09-.4]). There was no association between CD4+ T-cell counts at 1 year post-CBT and subsequent risk for HZ.

CONCLUSIONS

We found a high incidence of HZ after CBT despite antiviral prophylaxis for > 1 year. Based on these findings, we suggest longer duration of prophylaxis for HZ after CBT. Compliance with antiviral prophylaxis, VZV-specific immune monitoring, and vaccination to mitigate HZ after CBT also require further study.

Reduced immunogenicity of the adjuvanted recombinant zoster vaccine after hematopoietic cell transplant: a pilot study

Shingrix is poorly immunogenic following allogeneic hematopoietic cell transplantation independent of age, CD4, and B-cell recovery. In hematopoietic cell transplantation recipients with antibody response to the vaccine, varicella zoster virus reactivation risk is not null.

Immune reconstitution and infectious complications following axicabtagene ciloleucel therapy for large B-cell lymphoma

Chimeric antigen receptor (CAR) T-cell therapy targeting CD19 has significantly improved outcomes in the treatment of refractory or relapsed large B-cell lymphoma (LBCL). We evaluated the long-term course of hematologic recovery, immune reconstitution, and infectious complications in 41 patients with LBCL treated with axicabtagene ciloleucel (axi-cel) at a single center. Grade 3+ cytopenias occurred in 97.6% of patients within the first 28 days postinfusion, with most resolved by 6 months. Overall, 63.4% of patients received a red blood cell transfusion, 34.1% of patients received a platelet transfusion, 36.6% of patients received IV immunoglobulin, and 51.2% of patients received growth factor (granulocyte colony-stimulating factor) injections beyond the first 28 days postinfusion. Only 40% of patients had recovered detectable CD19+ B cells by 1 year, and 50% of patients had a CD4+ T-cell count <200 cells per μL by 18 months postinfusion. Patients with durable responses to axi-cel had significantly longer durations of B-cell aplasia, and this duration correlated strongly with the recovery of CD4+ T-cell counts. There were significantly more infections within the first 28 days compared with any other period of follow-up, with the majority being mild-moderate in severity. Receipt of corticosteroids was the only factor that predicted risk of infection in a multivariate analysis (hazard ratio, 3.69; 95% confidence interval, 1.18-16.5). Opportunistic infections due to Pneumocystis jirovecii and varicella-zoster virus occurred up to 18 months postinfusion in patients who prematurely discontinued prophylaxis. These results support the use of comprehensive supportive care, including long-term monitoring and antimicrobial prophylaxis, beyond 12 months after axi-cel treatment.

Herpes Zoster Risk in Immunocompromised Adults in the United States: A Systematic Review

BACKGROUND

The primary reported risk factors for herpes zoster (HZ) include increasing age and immunodeficiency, yet estimates of HZ risk by immunocompromising condition have not been well characterized. We undertook a systematic literature review to estimate the HZ risk in immunocompromised patients.

METHODS

We systematically reviewed studies that examined the risk of HZ and associated complications in adult patients with hematopoietic cell transplants (HCT), cancer, human immunodeficiency virus (HIV), and solid organ transplant (SOT). We identified studies in PubMed, Embase, Medline, Cochrane, Scopus, and clinicaltrials.gov that presented original data from the United States and were published after 1992. We assessed the risk of bias with Cochrane or Grading of Recommendations Assessment, Development, and Evaluation methods.

RESULTS

We identified and screened 3765 records and synthesized 34 studies with low or moderate risks of bias. Most studies that were included (32/34) reported at least 1 estimate of the HZ cumulative incidence (range, 0-41%). There were 12 studies that reported HZ incidences that varied widely within and between immunocompromised populations. Incidence estimates ranged from 9 to 92 HZ cases/1000 patient-years and were highest in HCT, followed by hematologic malignancies, SOT, and solid tumor malignancies, and were lowest in people living with HIV. Among 17 HCT studies, the absence of or use of antiviral prophylaxis at <1 year post-transplant was associated with a higher HZ incidence.

CONCLUSIONS

HZ was common among all immunocompromised populations studied, exceeding the expected HZ incidence among immunocompetent adults aged ≥60 years. Better evidence of the incidence of HZ complications and their severity in immunocompromised populations is needed to inform economic and HZ vaccine policies.

Varicella Zoster Virus-Associated Meningitis as a Rebound Varicella Zoster Disease after Antiviral Discontinuation

Varicella zoster virus (VZV)-associated meningitis is usually progressive and can be fatal, and early diagnosis and aggressive treatment with intravenous antivirals such as acyclovir (ACV) are required in immunocompromised patients. Patients receiving corticosteroids and immunosuppressive therapy have a significantly higher risk of VZV-associated meningitis. In this report, we describe an unusual case of herpes zoster (HZ) in a young woman who was first diagnosed during tapering of prednisone for dermatomyositis. The skin lesions affected the left L2 and L3 dermatomes, which is unusual in VZV-associated meningitis. Despite showing a good rapid response to antivirals, she developed VZV-associated meningitis immediately after discontinuation of ACV. This phenomenon is often called rebound VZV reactivation disease and occurs after discontinuation of antivirals. This case was notable in that the affected dermatomes were distant from the cranial nerves. Thus, progression of HZ to VZV reactivation-associated meningitis can occur even in appropriately treated HZ patients. Continuation of antivirals beyond 1 week in patients on immunosuppressive therapy may be associated with a decreased risk of severe rebound VZV disease, such as VZV-associated meningitis.

Infectious complications in allogeneic hematopoietic cell transplant recipients: Review of transplant-related risk factors and current state of prophylaxis

Allogeneic hematopoietic cell transplantation is a complex procedure that carries a significant risk of complications. Infections are among the most common of them. Several direct factors such as neutropenia, hypogammaglobulinemia, lymphopenia, mucosal barrier injury, and graft-versus-host disease have been shown to be associated with increased infectious risk post-transplant. Apart from direct factors, there are also indirect transplant-related factors that are the primary trigger to the formers' development. The most important of them are type of preparative regimen, graft source, donor type, graft-versus-host disease prophylaxis, and graft manipulation techniques. In this review, an attempt has been made to summarize the role of the transplant-related factors in the development of infectious complications and provide evidence underlying the current concept of infectious disease prophylaxis in patients after allogeneic hematopoietic cell transplantation.

Herpes zoster during arsenic trioxide therapy for acute promyelocytic leukemia

Historically, arsenic exposure has been associated with herpes zoster (HZ) infection, however the risk is not well characterized in arsenic trioxide (ATO) treated patients with acute promyelocytic leukemia (APL). We aimed to characterize the risk of HZ in 112 ATO treated patients with APL with and without antiviral prophylaxis (AVP). HZ occurred in 13/112 (11.6%) within 6 months of completing ATO, including one case of HZ encephalitis. AVP reduced the incidence of HZ (17.5% vs. 4.1%, RR 0.24 [95% CI 0.05-1.0, p = .025]) with a number needed to treat of 7.7. HZ despite AVP occurred later than HZ in patients without AVP (7.8 vs. 2.3 months from starting ATO, p = .11). Older age and prior HZ increased the risk of HZ in patients not receiving AVP. Routine AVP should be considered in patients with APL receiving ATO, particularly in older patients and those with a history of HZ.

Management of Mantle Cell Lymphoma in the Era of Novel Oral Agents

Objectives: To discuss (1) recent and emerging data for pharmacological management of untreated and relapsed/refractory (R/R) mantle cell lymphoma (MCL) with agents approved in the United States, (2) important considerations for toxicity monitoring and management, and (3) preliminary data and ongoing studies for agents in MCL-specific clinical trials. Data Sources: PubMed/MEDLINE, EMBASE, Google Scholar, product labeling, National Comprehensive Cancer Network, American Cancer Society, and ClinicalTrials.gov were searched for studies published between January 1, 2017, and January 31, 2020, and key historical trials. Study Selection and Data Extraction: Relevant studies conducted in humans and selected supporting preclinical data were reviewed. Data Synthesis: MCL is a rare but usually aggressive non-Hodgkin lymphoma that most commonly affects the older population. Traditionally, the treatment of MCL has been determined based on transplant eligibility. Newer data suggest that more tolerable frontline therapy may produce outcomes similar to intensive historical induction regimens, possibly precluding fewer patients from autologous stem cell transplant and producing better long-term outcomes in transplant-ineligible patients. In the R/R setting, novel regimens are improving outcomes and changing the landscape of treatment. Relevance to Patient Care and Clinical Practice: This review summarizes and discusses recent and emerging data for management of newly diagnosed and R/R MCL; key supportive care considerations for agents are also discussed. Conclusions: Recent study results are changing management of MCL. Although these data have complicated the picture of regimen selection, increasingly effective and tolerable therapy and additional anticipated data point to a brighter future for patients with MCL.

Pathogen-Specific T Cells Beyond CMV, EBV and Adenovirus

PURPOSE OF REVIEW

Infectious diseases contribute significantly to morbidity and mortality in recipients of allogeneic haematopoietic stem cell transplantation (aHSCT), particularly in the era of highly immunosuppressive transplant regimens and alternate donor transplants. Delayed cellular immune recovery is a major mechanism for the increased risk in these patients. Adoptive cell therapy with ex vivo manipulated pathogen-specific T cells (PSTs) is increasingly taking its place as a treatment strategy using donor-derived or third party-banked cells.

RECENT FINDINGS

The majority of clinical trial data in the form of early-phase studies has been in the prophylaxis or treatment of cytomegalovirus (CMV), Epstein-Barr virus (EBV) and adenovirus (AdV). Advancements in methods to select and enrich PSTs offer the opportunity to target the less common viral pathogens as well as fungi with this technology. Early clinical studies of PSTs targeting polyomaviruses (BK virus and JC virus), human herpesvirus 6 (HHV6), varicella zoster virus (VZV) and Aspergillus spp. have shown promising results in small numbers of patients. Other potential targets include herpes simplex virus (HSV), respiratory viruses and other invasive fungal species. In this review, we describe the burden of disease of this wider spectrum of pathogens, the progress in the development of manufacturing capability, early clinical results and the opportunities and challenges for implementation in the clinic.

Herpes Virus Infections Other than Cytomegalovirus in the Recipients of Hematopoietic Stem Cell Transplantation

This review discusses the epidemiologic and clinical aspects of herpes viruses other than cytomegalovirus in patients who have undergone hematopoietic stem cell transplantation.

Antimicrobial Prophylaxis and Preemptive Approaches for the Prevention of Infections in the Stem Cell Transplant Recipient, with Analogies to the Hematologic Malignancy Patient

Infectious complications represent one of the most common causes of morbidity and mortality in allogeneic hematopoietic cell transplant (HCT) recipients. Prophylactic and preemptive treatment strategies against bacterial, fungal, viral, and parasitic pathogens are routinely implemented during high-risk post-HCT periods at most transplant centers. The basic concepts and review of current guidelines of antibiotic prophylaxis and empirical/preemptive antibiotic treatment in allogeneic HCT recipients are reviewed in this article.

Anti-herpesvirus prophylaxis, pre-emptive treatment or no treatment in adults undergoing allogeneic transplant for haematological disease: systematic review and meta-analysis

BACKGROUND

Herpesviridae infections incur significant morbidity and indirect effects on mortality among allogeneic haematopoietic cell transplant (allo-HCT) recipients.

OBJECTIVES

To study the effects of antiviral prevention strategies among haemato-oncological individuals undergoing allo-HCT.

DATA SOURCES

Cochrane Central Register of Controlled Trials, MEDLINE, Embase and LILACS. We further searched for conference proceedings and trial registries.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials (RCTs).

PARTICIPANTS

Adults with haematological malignancy undergoing allo-HCT.

INTERVENTIONS

Antiviral prophylaxis versus no treatment/placebo or pre-emptive treatment and pre-emptive treatment versus prophylaxis with the same agent.

METHODS

Random-effects meta-analysis was conducted computing pooled risk ratios (RR) with 95% CI and the inconsistency measure (I²). The certainty of the evidence was appraised by GRADE.

RESULTS

We included 22 RCTs. Antiviral prophylaxis reduced all-cause mortality (RR 0.83, 95% CI 0.7-0.99; 15 trials, I² = 0%), cytomegalovirus (CMV) disease (RR 0.54, 95% CI 0.34-0.85; n = 15, I² = 20%) and herpes simplex virus (HSV) disease (RR 0.29, 95% CI 0.2-0.43; n = 13, I² = 18%) compared with no treatment/placebo or pre-emptive treatment, all with high-certainty evidence. Furthermore, antivirals reduced HSV infection, CMV pneumonitis, CMV infection and varicella zoster virus disease. Anti-CMV prophylaxis (+/- pre-emptive treatment) compared with pre-emptive treatment alone reduced non-significantly all-cause mortality (RR 0.78, 95% CI 0.6-1.02; n = 8, I² = 0%), CMV disease (RR 0.47, 95% CI 0.23-0.97; n = 9, I² = 30%) and HSV disease (RR 0.41, 95% CI 0.24-0.67; n = 4, I² = 0%) with high-certainty evidence, as well as CMV and HSV infections. Antiviral prophylaxis did not result in increased adverse event rates overall or more discontinuation due to adverse events.

CONCLUSIONS

Antiviral prophylaxis directed against herpesviruses is highly effective and safe, reducing mortality, HSV and CMV disease, as well as herpesvirus reactivations among allo-HCT recipients. Anti-CMV prophylaxis is more effective than pre-emptive treatment alone with respect to HSV and CMV disease and infection.

Late-onset visceral varicella-zoster virus infection presented as acute liver failure after allogeneic hematopoietic stem cell transplantation

Although much less common than localized zoster, initial presentation of varicella-zoster virus (VZV) as visceral infection can occur especially after allogeneic hematopoietic stem cell transplantation (HSCT). We herein report a case of post-transplant visceral VZV infection presenting as fatal acute liver failure. It developed 4 years after allogeneic HSCT when a long-term prophylactic anti-VZV agent administration was discontinued. VZV should be listed as a causative pathogen of acute liver failure even years after allogeneic HSCT. Indication for, and duration of anti-VZV prophylaxis should be further investigated.

Low-Dose Acyclovir Prophylaxis for Varicella zoster Reactivation in Autologous Hematopoietic Cell Transplantation Recipients

Varicella zoster virus (VZV) reactivation after autologous hematopoietic cell transplantation (auto-HCT) may be observed in a quarter of patients. Currently, prophylactic use of acyclovir 800 mg twice daily or valacyclovir 500 mg twice daily is recommended for prophylaxis against VZV reactivation for at least one-year post-HCT, with continued use recommended in immunosuppressed recipients. Acyclovir dosing regimens vary between institutions despite the noted recommendations. In this single-center, retrospective study, recipients of auto-HCT who received at least one year of low-dose antiviral prophylaxis defined as the equivalent of acyclovir 400 mg orally twice daily or valacyclovir 500 mg daily were included. The primary objective of this study was to assess the incidence of VZV reactivation with low-dose acyclovir/valacyclovir prophylaxis in autograft recipients. One hundred and eighty patients undergoing auto-HCT between April 2008 and March 2015 were included. Patients received low-dose acyclovir, for a median duration of 55.5 months (range 12–100). There were no occurrences of VZV reactivation while patients were on these drugs. However, 2 patients (1.1%) had VZV reactivation after discontinuation of therapy, occurring 18.8 and 14 months from transplant and 6.7 and 2 months after stopping prophylaxis, respectively. Our retrospective analysis found low-dose antiviral prophylaxis with oral acyclovir 400 mg twice daily or valacyclovir 500 mg daily to be effective in preventing VZV reactivation in auto-HCT recipients.

Severe Herpes Zoster Requiring Intravenous Antiviral Treatment in Allogeneic Hematopoietic Cell Transplantation Recipients on Standard Acyclovir Prophylaxis

Allogeneic hematopoietic cell transplantation (HCT) recipients are at increased risk for varicella zoster virus (VZV) reactivation and associated complications. The incidence, timing, and risk factors for severe herpes zoster (HZ) are not well described in the era of acyclovir (ACV) prophylaxis. We performed a retrospective cohort study of all patients who underwent first allogeneic HCT between October 2006 and December 2015 at our institution. Patients were followed until December 2017 for the development of severe HZ, defined as necessitating administration of i.v. antiviral medication. Out of 2163 patients who underwent allogeneic HCT, 22 (1.0%) developed severe HZ at a rate of 1 per 228 person-years, including dermatomal/multidermatomal disease (n = 5), disseminated skin disease (n = 5), HZ ophthalmicus (n = 4), meningitis/encephalitis (n = 4), pneumonia (n = 2), viremia (n = 1), and erythema multiforme (n = 1). Severe HZ infection occurred in a bimodal distribution during the early peri-HCT period and at 12 to 24 months post-HCT (median, 12.7 months). Twelve patients (54.5%) were compliant with ACV prophylaxis at the time of HZ diagnosis. Eleven patients (50%) died during the study period, only 2 of whom (9.1%) with active VZV infection. Mortality was higher in patients on immunosuppressive therapy (62.5% versus 16.7%; P = .045) and with concurrent graft-versus-host disease (75.0% versus 35.7%; P= .044). These data suggest that severe HZ remains an important consideration despite ACV prophylaxis.

Varicella-Zoster Virus-Induced Hepatitis in a Liver Transplant Recipient: A Case Report

Infections after solid organ transplantation are a major cause of mortality and morbidity. Varicella-zoster virus (VZV) infection after solid organ transplantation is rare. Here we present a case presenting with acute hepatitis and shingles after a liver transplantation (LT). A 36-year-old male patient underwent a liver transplantation; 7 months later his liver function tests increased. An examination and test results revealed that he had VZV-induced hepatitis. After VZV treatment, his test results returned to normal levels. Hepatic involvement of VZV infection is rare, but it may be fatal in immunocompromised individuals. Early diagnosis and early initiation of antiviral therapy is important in the control of hepatitis and rare hepatotropic viruses in immunocompromised individuals.

Herpes simplex virus infections in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of HSV in the pre- and post-transplant period. A majority of transplant recipients are seropositive for HSV-1 or 2. Compared with immunocompetent persons, SOT recipients shed HSV more frequently, have more severe clinical manifestations, and are slower to respond to therapy. Most HSV infection is diagnosed on clinical grounds, but patients may present with atypical lesions and/or other clinical manifestations. Acquisition from the donor is rare. Polymerase chain reaction is the preferred diagnostic test unless culture is needed for resistance testing. For limited mucocutaneous lesions, oral therapy can be used; however, in severe, disseminated, visceral or CNS involvement, acyclovir doses of up to 10 mg/kg every 8 hours intravenously should be initiated. Acyclovir-resistant HSV is less common in SOT patients than in HSCT and can be treated with foscarnet, though other novel therapies are currently under investigation. HSV-specific prophylaxis should be considered for all HSV-1 and HSV-2-seropositive organ recipients who are not receiving antiviral medication for CMV prevention that has activity against HSV.

Antiviral prophylaxis for cytomegalovirus infection in allogeneic hematopoietic cell transplantation

Patients treated with allogeneic hematopoietic cell transplantation (HCT) are at risk of cytomegalovirus (CMV) reactivation and disease, which results in increased morbidity and mortality. Although universal antiviral prophylaxis against CMV improves outcomes in solid organ transplant recipients, data have been conflicting regarding such prophylaxis in patients undergoing allogeneic HCT. We conducted a systematic review of randomized trials of prophylactic antivirals against CMV after allogeneic HCT to summarize the evolution of the field over the last 35 years and evaluate the prophylactic potential of antiviral agents against CMV after allogeneic HCT. Electronic databases were queried from database inception through 31 December 2017. For included studies, incidence of CMV infection and all-cause mortality were collected as primary outcomes; CMV disease incidence, use of preemptive therapy, and drug toxicities were collected as secondary outcomes. Nineteen clinical trials conducted between 1981 and 2017 involving a total of 4173 patients were included for review. Prophylactic strategies included use of acyclovir, valacyclovir, ganciclovir, maribavir, brincidofovir, and letermovir compared with placebo or a comparator antiviral. Fourteen trials that compared antiviral prophylaxis with placebo demonstrated overall effectiveness in reducing incidence of CMV infection (odds ratio [OR], 0.49; 95% confidence interval [CI], 0.42-0.58), CMV disease (OR, 0.56; 95% CI, 0.40-0.80), and use of preemptive therapy (OR, 0.51; 95% CI, 0.42-0.62; 6 trials); however, none demonstrated reduction in all-cause mortality (OR, 0.96; 95% CI, 0.78-1.18) except the phase 3 trial of letermovir (week-24 OR, 0.59; 95% CI, 0.38-0.98). Additional research is warranted to determine patient groups most likely to benefit from antiviral prophylaxis and its optimal deployment after allogeneic HCT.

Effectiveness of acyclovir prophylaxis against varicella zoster virus disease after allogeneic hematopoietic cell transplantation: A systematic review and meta-analysis

BACKGROUND

Varicella zoster virus (VZV) disease is a common complication after hematopoietic cell transplantation (HCT). The mortality rate for disseminated VZV infection is 34%. Acyclovir has been used for the prophylaxis of VZV disease after HCT, but the effectiveness of prophylaxis is controversial. We conducted a meta-analysis of the incidence of VZV disease within the first 1 year after acyclovir prophylaxis had been discontinued and assessed the risk of VZV disease during acyclovir prophylaxis.

METHODS

Medline, EMBASE plus EMBASE classics, and the Cochrane Central Register of Controlled Trials were used for a systematic search. The inclusion criteria were both randomized controlled trials and cohort studies that described the effectiveness of acyclovir as prophylaxis against VZV disease after allogeneic HCT.

RESULTS

We included seven studies involving a total of 2265 patients. No mortality by VZV was identified. Acyclovir prophylaxis significantly reduced the rate of VZV infection within the first 1 year after discontinuation (risk ratio: 0.38, 95% confidence interval (CI): 0.29-0.51). The risk of VZV disease during acyclovir prophylaxis was also reduced (risk ratio: 0.17, 95% CI: 0.12-0.24). Both short-term and long-term prophylaxis reduced the incidence of VZV infection (RR: 0.51, 95% CI: 0.30-0.86 vs RR: 0.34, 95% CI: 0.22-0.54). Low-dose acyclovir (<400 mg/d) is sufficient to reduce the risk of VZV disease.

CONCLUSION

This study showed that acyclovir prophylaxis reduced VZV infection after HCT with no fatal cases and acyclovir prophylaxis is beneficial. No significant adverse effects occurred and no delayed VZV disease was identified.

Overview of Infections Complicating Pediatric Hematopoietic Cell Transplantation

Hematopoietic cell transplantations (HCT) are increasingly being performed in children for the treatment of malignant and nonmalignant diseases. Infections remain an important cause of morbidity and mortality after HCT, where the type and timing of infection is influenced by host, transplant, and pathogen-related factors. Herein, an overview of the epidemiology of infections is presented and organized by timing before and after HCT, understanding that infection may occur at any time point until there is successful immune reconstitution.

Immune responses to zoster vaccines

There are two licensed herpes zoster vaccines. One is a live vaccine (ZVL) based on an attenuated varicella-zoster virus (VZV). The other is a recombinant vaccine (RZV) based on the VZV glycoprotein E (gE) combined with AS01B, a multicomponent adjuvant system. RZV is superior to ZVL in efficacy, and differs from ZVL in that protection is not diminished by the age of the vaccinee and has not waned significantly during 4 years of follow-up. Immunologic studies demonstrated higher peak memory and persistence of T cell responses in RZV compared with ZVL recipients. RZV recipients also showed development and persistence of polyfunctional T cell responses. Taken together, we conclude that the immunologic data parallel and support the higher efficacy over time of RZV compared with ZVL.

Infections in Hematology Patients

Infections are major causes of morbidity and mortality in hematology patients especially those having undergone allogeneic hematopoietic stem cell transplantation. The management relies on early diagnosis and rapid introduction of appropriate antimicrobial drugs frequently before the infectious agent has been identified. The use of broad-spectrum antibacterial drugs has reduced the mortality in febrile neutropenia. However, the increase of multiresistant strains has in several countries become a major threat, and the development of new antibacterial drugs is urgently needed. Infection control strategies are also very important to limit the spread of multiresistant bacteria. Early diagnosis with imaging and tests for antigen or DNA is important for the management of fungal infections. High-risk patients should also receive prophylaxis. Viral infections are important causes of severe disease in patients having undergone allogeneic stem cell transplantation but do occur also in non-transplanted patients. Early diagnosis usually with tests for viral nucleic acids is the key for appropriate management. Prevention and treatment with antiviral drugs are available for some viruses especially herpesviruses.

Abdominal pain, unconsciousness, and skin rash after lung transplantation

Long-term success of lung transplantation is limited by allograft dysfunction and frequent infections. Varicella zoster virus infection (VZV) is one of the most common opportunistic infections among solid organ transplantation recipients. However the occurrence of visceral involvement or disseminated disease, as seen after bone marrow transplantation, is rare. We report a case of a 59-year-old woman who underwent double-lung transplantation with a fatal visceral and disseminated varicella zoster virus infection.

Comparative Efficacy and Safety of Different Antiviral Agents for Cytomegalovirus Prophylaxis in Allogeneic Hematopoietic Cell Transplantation: A Systematic Review and Meta-Analysis

Over the past 25 years, several randomized controlled trials have investigated the efficacy of different antiviral agents for cytomegalovirus (CMV) prophylaxis in allogeneic hematopoietic cell transplantation. We performed a systematic literature review, conventional meta-analysis, and network meta-analysis using a random-effects model and risk ratios (RRs) with corresponding 95% confidence intervals (CIs) as effect estimates. Fifteen randomized controlled trials were identified, including 7 different antiviral agents: acyclovir, ganciclovir, maribavir, brincidofovir, letermovir, valacyclovir, and vaccine. Twelve trials used placebo as comparator while 3 trials compared different antiviral agents. We found evidence for CMV disease and infection being significantly reduced by antiviral prophylaxis, with an RR of .66 (95% CI, .48 to .90) and .63 (95% CI, .50 to .79). Across the network, ganciclovir showed the best relative efficacy for CMV disease while letermovir provided first rank of being the best option for CMV infection. The risk for death was not significantly influenced by antiviral prophylaxis in the meta-analysis, with an RR of .92 (95% CI, .78 to 1.08), as well as in the network meta-analysis. In terms of safety, letermovir was at least similar in comparison with placebo and most agents while both letermovir and acyclovir showed significantly reduced risk for serious adverse events compared with ganciclovir, with RRs of .55 (95% CI, .30 to 1.00) for letermovir and .63 (95% CI, .42 to .93) for acyclovir. With a probability of 81%, letermovir appears to be the best option in terms of safety. Future randomized head-to-head comparisons are needed to evaluate the definite efficacy and safety of different prophylactic strategies.

Varicella Zoster Virus Reactivation in Adult Survivors of Hematopoietic Cell Transplantation: How Do We Best Protect Our Patients?

Reactivation of varicella zoster virus (VZV) remains a significant public health burden for long-term survivors of hematopoietic cell transplantation. Delayed immune reconstitution after transplantation due to immunosuppression, post-transplant therapies, poor engraftment, and graft-versus-host disease leave a large number of patients at risk for herpes zoster (shingles) and its highly morbid complications. Although prophylaxis with acyclovir or valacyclovir has reduced the incidence of VZV reactivation as long as prophylaxis is continued, the incidence of disease in the late post-transplant period or after stopping prophylaxis is greater in the hematopoietic cell transplantation population than the general public. Therefore, additional interventions beyond long-term use of prophylactic antivirals are required to suppress VZV. Vaccines to elicit VZV-specific immunity represent one method to enhance prevention of VZV reactivation, but care must be taken with live vaccines. Inactivated vaccines have been developed and require well-designed studies to determine their safety and efficacy in this high-risk population. Here, we report the available evidence for established and newly developed vaccines for VZV and discuss our view on their role in protecting our transplant survivors against VZV reactivation.

Herpes zoster incidence and cost in patients receiving autologous hematopoietic stem-cell transplant

OBJECTIVE

Among patients receiving autologous hematopoietic stem cell transplant (Auto-HSCT), this study estimated the incidence of herpes zoster (HZ), compared healthcare costs among patients with and without HZ, and evaluated antiviral prophylaxis (AP) use.

RESEARCH DESIGN AND METHODS

A retrospective study was conducted using data from a large health plan to identify patients ≥18 years with ≥1 claim for an Auto-HSCT procedure during 2006-2011 (n = 2,530). Patients were followed from date of Auto-HSCT until risk-end date, defined as development of HZ, end of enrollment, death, or December 31, 2011. HZ incidence was calculated as cases observed after Auto-HSCT, divided by accrued time-at-risk in person-years (PY). AP use and duration were defined by prescription fills. One-year medical and pharmacy costs were calculated as combined health plan and patient paid amounts.

MAIN OUTCOME MEASURES

HZ incidence and healthcare costs were calculated using administrative claims data.

RESULTS

Overall HZ incidence was 62.2/1,000 PY (95% CI = 54.3-70.9). Most (72.3%) patients were prescribed AP. During the first 90-days post-Auto-HSCT, patients without AP had increased incidence (151.6/1,000 PY, 95% CI = 88.3-242.6) compared to those prescribed AP pre- (30.9/1,000 PY, 95% CI = 11.3-67.2) or post-Auto-HSCT (33.0/1,000 PY, 95% CI = 13.3-67.9). Total adjusted mean 1-year all-cause healthcare costs were $74,875 for patients who developed HZ and $70,279 for patients who did not (difference = $4,596 (cost ratio = 1.07, 95% CI = 0.86-1.32, p = .566)).

CONCLUSIONS

HZ incidence was high, despite AP use. Mean annual healthcare costs were higher for patients with HZ, but the difference was not statistically significant. An effective vaccine against HZ could be useful in decreasing both incidence of and cost for HZ in this population.