Oral ganciclovir versus valganciclovir for cytomegalovirus prophylaxis in high-risk liver transplant recipients

Comparison of standard versus low-dose valganciclovir regimens for cytomegalovirus prophylaxis in high-risk liver transplant recipients

PURPOSE

The purpose of this study was to compare the safety and efficacy of two valganciclovir (VGCV) institutional dosing protocols for cytomegalovirus (CMV) prophylaxis in liver transplant (LT) recipients with CMV serotype donor +/recipient- (D+/R-).

METHODS

This was a single-center review of CMV D+/R- adult LT recipients who received VGCV 450 mg/day for 90 days (low-dose) or VGCV 900 mg/day for 180 days (standard-dose). The primary outcome was incidence of CMV disease at 1 year. Secondary outcomes included rates of CMV syndrome, end-organ disease, breakthrough infection, and resistance. Neutropenia, early discontinuation of VGCV, growth colony stimulating factors use (G-CSF), biopsy-proven rejection (BPAR), graft loss, and death at 1 year were analyzed.

RESULTS

Ninety-six CMV D+/R- LT recipients were included. Although no difference in CMV disease was observed (low-dose 26% vs. standard-dose 23%, p = 0.71), 75% of CMV infections in the low-dose group presented with end-organ disease. Ganciclovir (GCV) resistance was observed only in the low-dose group (n = 2). Significantly more patients in the standard-dose group developed neutropenia (low-dose 10% vs 60% standard-dose, p < 0.001). In the standard-dose group, 29% required early discontinuation of VGCV (vs. 5% in the low-dose group, p < 0.001), and 20% were treated with G-CSF. Both cohorts had similar rates of BPAR, graft loss, and death at 1 year.

CONCLUSIONS

VGCV 900 mg/day for 180 days had higher rates of hematologic adverse effects resulting in frequent treatment interruptions. However, the occurrence of two cases of GCV-resistant CMV disease raises concerns about routinely using low-dose VGCV prophylaxis.

Population pharmacokinetics of valganciclovir prophylaxis in paediatric and adult solid organ transplant recipients

AIM

Our aims were to quantify ganciclovir pharmacokinetics in paediatric and adult kidney, liver and lung transplant patients taking a range of valganciclovir doses to prevent herpes virus infections, including a 450 mg regimen, and to identify sources of pharmacokinetic variability.

METHOD

Plasma samples were collected at 2, 4, 8 and 12 weeks post-transplant and at 4, 6, 8 and 12 months post-transplant in subjects prescribed longer courses. Ganciclovir was measured by liquid chromatography/ultraviolet detection. Non-linear mixed effects modelling was used to analyze the concentration-time data and evaluate demographic and transplant-related covariates.

RESULTS

A two compartment model with first order absorption best described the data. Given the range of body sizes, clearance and volume of distribution terms were scaled using standard weight-based allometric exponents. Creatinine clearance was included on apparent oral clearance. Final estimates in a standard 70 kg individual for apparent oral clearance, central volume of distribution, intercompartmental clearance and peripheral volume of distribution were 14.5 l h(-1) , 87.5 l, 4.80 l h(-1) and 42.6 l, respectively. The median terminal half-life for kidney, liver and lung transplant recipients was 9.4, 9.5 and 8.2 h, respectively. Median exposure (i.e. AUC(0,∞) in subjects taking valganciclovir 900 mg or 450 mg once daily was 57.4 and 34.3 μg ml(-1)  h, respectively.

CONCLUSION

Allometric scaling allowed simultaneous analysis of data from children and adults. Ganciclovir pharmacokinetics were similar among kidney, liver and lung transplant recipients. Ganciclovir exposure after valganciclovir 450 mg once daily may be suboptimal in some individuals and requires evaluation along with virologic outcomes data.

Universal prophylaxis or preemptive strategy for cytomegalovirus disease after liver transplantation: a systematic review and meta-analysis

We systematically reviewed and meta-analyze the efficacy of universal prophylaxis (UP) and preemptive (PE) strategies (using ganciclovir or valganciclovir) in preventing cytomegalovirus (CMV) disease (CMD) among liver transplant recipients (LTRs). We performed an electronic search of MEDLINE, EMBASE and the Cochrane Database till December 2013. Studies that assessed UP or PE for preventing CMD in LTRs were included. The risk of bias was assessed using the Newcastle-Ottawa scale. The primary outcome was CMD, secondary outcomes being acute cellular rejection (ACR), graft loss (GL) and mortality. Due to the heterogeneity of comparative studies, an indirect comparison was performed. Pooled incidence rates with 95% confidence interval (CI) are calculated for each outcome using a random-effects model. Thirty-two studies involving 2456 LTRs were included. The majority of the studies were of low risk of bias. Irrespective of donor/recipient CMV sero-status, CMD was 10% with UP (95% CI: 6-14; I(2)  = 87%; 16 studies, n = 1581) and 7% with PE (95% CI: 3-10; I(2)  = 84%; 16 studies, n = 875) (mean difference 2.6; 95% CI: -3.25 to 8.45, p = 0.34). Likewise, ACR and mortality were similar with the two strategies. However, GL was significantly lower in the UP group, regardless of donor/recipient sero-status. In indirect comparison, the incidence of CMD, ACR and mortality in LTRs were similar with two strategies. Trials comparing the two strategies directly are needed.

Cytomegalovirus infection in liver transplant recipients: Updates on clinical management

Cytomegalovirus (CMV) infection is a common complication after liver transplantation, and it is associated with multiple direct and indirect effects. Management of CMV infection and disease has evolved over the years, and clinical guidelines have been recently updated. Universal antiviral prophylaxis and a pre-emptive treatment strategy are options for prevention. A currently-recruiting randomized clinical trial is comparing the efficacy and safety of the two prevention strategies in the highest risk D+R- liver recipients. Drug-resistant CMV infection remains uncommon but is now increasing in incidence. This highlights the currently limited therapeutic options, and the need for novel drug discoveries. Immunotherapy and antiviral drugs with novel mechanisms of action are being investigated, including letermovir (AIC246) and brincidofovir (CMX001). This article reviews the current state of CMV management after liver transplantation, including the updated practice guidelines, and summarizes the data on investigational drugs and vaccines in clinical development.

Prevention of cytomegalovirus following solid organ transplantation: a literature review

CMV is the most common opportunistic infection affecting SOT recipients. Although current strategies to prevent both CMV infection and disease have been effective, CMV related complications continue to occur, particularly late-onset CMV disease. This literature review article examines the benefits and disadvantages of different prevention modalities, and presents emerging strategies to better prevent CMV in organ transplant recipients.

Updated international consensus guidelines on the management of cytomegalovirus in solid-organ transplantation

Cytomegalovirus (CMV) continues to be one of the most common infections after solid-organ transplantation, resulting in significant morbidity, graft loss, and adverse outcomes. Management of CMV varies considerably among transplant centers but has been become more standardized by publication of consensus guidelines by the Infectious Diseases Section of The Transplantation Society. An international panel of experts was reconvened in October 2012 to revise and expand evidence and expert opinion-based consensus guidelines on CMV management, including diagnostics, immunology, prevention, treatment, drug resistance, and pediatric issues. The following report summarizes the recommendations.

Risk of cytomegalovirus disease in high-risk liver transplant recipients on valganciclovir prophylaxis: a systematic review and meta-analysis

Valganciclovir (VGC) was approved by the Food and Drug Administration in 2004 as cytomegalovirus (CMV) prophylaxis except for liver transplant recipients because of their high incidence of CMV disease with this drug. However, surveys have shown its common off-label use for CMV prophylaxis in liver transplant recipients. We aimed to evaluate the risk of CMV disease with VGC prophylaxis in liver transplant recipients. All studies that evaluated liver transplant recipients and used VGC (900 or 450 mg daily) for the prevention of CMV disease were included. Five controlled studies (n = 483) were pooled with a random effects model; five single-arm studies (n = 380) were pooled for the prevalence rate of CMV disease. The risk of CMV disease with VGC versus ganciclovir was 1.81 [95% confidence interval (CI) = 1.00-3.29, P = 0.05, I(2) = 0%]. For high-risk (donor-positive/recipient-negative) patients, the risk of CMV disease was 1.96 (95% CI = 1.05-3.67, P = 0.035, I(2) = 0%). The risk of CMV disease remained significant with 900 mg of VGC daily (P = 0.04) but not with 450 mg of VGC daily (P = 0.76). The risk of leukopenia with VGC was 1.87 (95% CI = 1.03-3.37, P = 0.04, I(2) = 0%). In single-arm trials, the overall CMV disease rate was 12% (95% CI = 9%-16%, P < 0.001), and the rate for high-risk patients was 20% (95% CI = 10%-38%, P = 0.002). In conclusion, 900 mg of VGC daily may not be safe as CMV prophylaxis in high-risk liver transplant recipients because of the significant 2-fold increase in the risk of CMV disease and the 1.9-fold increase in the risk of leukopenia. Alternative CMV prophylaxis should be used for liver transplant recipients.

Retrospective review of the incidence of cytomegalovirus infection and disease after liver transplantation in pediatric patients: comparison of prophylactic oral ganciclovir and oral valganciclovir

Cytomegalovirus (CMV) is the most common viral infection after solid organ transplantation (SOT). Safe and effective prophylactic regimens that decrease its incidence after SOT are essential for long-term graft survival. Although valganciclovir is not Food and Drug Administration-approved for CMV prophylaxis in liver transplant recipients, postmarketing studies have shown valganciclovir to be as effective as ganciclovir in high-risk adult patients undergoing SOT. Currently, data are lacking for pediatric liver transplantation. The purpose of this study was to compare the efficacy and safety of valganciclovir and ganciclovir for CMV infection prophylaxis in pediatric liver transplant recipients. This was a retrospective study of 56 pediatric liver transplant recipients who were prescribed either oral ganciclovir (n = 37) or valganciclovir (n = 19). Patients were followed until 200 days after transplantation or death. The primary outcome measure compared the rates of early-onset CMV infection and CMV disease in the 2 medication groups. Secondary outcome measures identified patient-specific factors that contributed to CMV acquisition and the incidence of late-onset CMV infection or disease. The rates of adverse drug effects and discontinuation were also evaluated. Early-onset CMV disease was documented in 0% of valganciclovir patients and in 5.4% of ganciclovir patients (P = 0.54). There were no statistically significant differences in the secondary outcomes. An increased incidence of late-onset CMV disease was seen in the valganciclovir group versus the ganciclovir group (22.2% versus 8.1%, P = 0.23). No differences in adverse events were reported. In conclusion, no statistically significant differences were found in the incidence of CMV infection or disease between patients receiving oral valganciclovir and patients receiving oral ganciclovir.

Viral factors influencing the outcome of human cytomegalovirus infection in liver transplant recipients

BACKGROUND

Cytomegalovirus (CMV) remains the leading viral cause of disease following orthotopic liver transplantation (OLT) despite the availability of antiviral agents for prophylaxis and therapy.

OBJECTIVE

Examine the viral factors that influence the outcome of CMV infection following valganciclovir prophylaxis or laboratory-guided preemptive therapy in OLT recipients.

STUDY DESIGN

The value of valganciclovir prophylaxis and laboratory-guided preemptive therapy for the prevention of CMV infection and disease was observed in 64 OLT recipients. Prophylaxis was given to all CMV seronegative recipients receiving a liver from a seropositive donor (D+R-; n=15), and all other recipients were randomised to receive either prophylaxis (n=24) or laboratory-guided preemptive therapy (n=25). Recipients were monitored for CMV DNAemia, viral load, emergence of antiviral resistant strains and co-infections.

RESULTS

CMV end-organ disease and antiviral resistant strains only occurred in D+R- recipients despite the use of prophylaxis in these patients. The D+R- recipients commencing prophylaxis immediately following transplantation had better outcomes compared to those for whom prophylaxis was delayed due to renal impairment. Prophylaxis reduced the incidence of CMV DNAemia, persistent infection, and high viral loads for CMV seropositive (D-R+and D+R+) recipients, but laboratory-guided preemptive therapy effectively controlled CMV infection and prevented disease in these OLT recipients.

CONCLUSION

Delaying the commencement of valganciclovir prophylaxis may be associated with worse outcomes for high-risk OLT recipients. Laboratory-guided pre-emptive therapy remains an alternative approach for seropositive recipients at lower risk of CMV disease.

Effectiveness of valganciclovir 900 mg versus 450 mg for cytomegalovirus prophylaxis in transplantation: direct and indirect treatment comparison meta-analysis

BACKGROUND

valganciclovir (VGC) 900 mg is approved for CMV prophylaxis, but it has been associated with 10%-40% leucopenia rate. We hypothesize that VGC 450 mg daily may be as effective as and safer than 900 mg daily.

METHODS

studies evaluating valganciclovir 900 mg and 450 mg daily against controls were evaluated. Direct comparisons were performed by random-effects models and indirect comparisons by the Bucher method.

RESULTS

twelve trials with VGC 900 mg (1543 patients) and 8 trials with VGC 450 mg (1531 patients) were included. The risk of CMV disease with VGC 900 mg versus controls was 1.06 (95% confidence interval [CI], .64-1.76; P = .81; I2=29%) and with VGC 450 mg vs controls .77 (95%CI, .49-1.18; P = .23; I2=24%). The risk of leucopenia was 5.24 (2.09-13.15; P = .0004; I2=44%) for VGC 900 mg versus controls and 1.58 (.96-2.61; P = .07; I2=36%) for VGC 450 mg versus controls; the risk for acute allograft rejection was 1.71 (.45, -6.50; P = .43) for VGC 900 mg and .80 (.50-1.28; P = .34) for VGC 450 mg. Adjusted indirect comparison between VGC 900 mg and VGC 450mg: the risk for CMV disease was not significantly different: odds ratio (OR), 1.38 (.84-2.25); P = .19; the risk of leucopenia was significantly increased with VGC 900 mg: 3.32 (1.76-6.26); P = .0002; and the risk of rejection was significantly increased with VGC 900 mg: 2.56 (1.50-4.53); P = .0005. Results remained consistent after adjustments by allograft, CMV control strategy, and immunosuppression.

CONCLUSIONS

valganciclovir 900 mg showed no superiority efficacy compared to controls (ganciclovir or preemptive) and equivalent efficacy to VGC 450 mg (statistical power: 94% and 97%, respectively) for CMV universal prophylaxis.VGC 900 mg was significantly associated with 3 times increase in the risk of leucopenia and 2 times increase in the risk of rejection compared with VGC 450 mg.

Valganciclovir is an effective prophylaxis for cytomegalovirus disease in liver transplant recipients

OBJECTIVES

Cytomegalovirus (CMV) infection is responsible for significant morbidity and mortality among solid organ transplant recipients. Prophylaxis using valganciclovir (VGCV) in orthotopic liver transplant (OLT) recipients is not approved by the Food and Drug Administration and its use is controversial. This study aimed to evaluate the effectiveness of VGCV in CMV prophylaxis in OLT recipients.

METHODS

We carried out a retrospective, single-centre study including all OLT procedures performed during 2005-2008. Patients with early death (at ≤ 30 days), without CMV serology or prophylaxis, or with follow-up of <1 year were excluded.

RESULTS

The overall incidence of CMV disease was 6% (n= 9). The ganciclovir (GCV) and VGCV groups had similar incidences of CMV disease (4.6% vs. 7.0%; P= 0.4) and similar distributions of disease presentation (CMV syndrome vs. tissue-invasive CMV; P= 0.4). Incidences of CMV infection, as well as disease presentation, were similar between the high-risk (CMV D+/R-) and non-high-risk groups (P= 0.16). Although acute cellular rejection occurred more frequently in patients who developed CMV disease (P= 0.005), overall survival in these patients did not differ from that in patients who did not develop CMV infection (P= 0.5).

CONCLUSIONS

Valganciclovir is an effective antiviral for the prevention of CMV disease in liver transplant recipients. Our data support its use in high-risk OLT patients.