Low-dose valganciclovir for cytomegalovirus prophylaxis in intermediate-risk liver transplantation recipients

Low-Dose Valganciclovir Prophylaxis Against Cytomegalovirus in Intermediate-Risk Liver and Dual-Abdominal Transplant Recipients

BACKGROUND

Low-dose valganciclovir (VGC) for cytomegalovirus (CMV) prophylaxis post-transplant has been employed due to cost and safety. The incidence of CMV disease in CMV intermediate-risk liver recipients at 1-year after standard-dose prophylaxis is approximately 5%. However, there are limited data on outcomes after using a "true" low-dose VGC prophylaxis regimen in liver and dual-abdominal transplant recipients as VGC was not dose-adjusted in all patients with impaired renal function in prior studies.

OBJECTIVE

The objective was to assess the incidence of CMV associated with low-dose VGC prophylaxis in CMV intermediate-risk liver, simultaneous pancreas-kidney (SPK), and simultaneous liver-kidney (SLK) recipients with creatinine clearance (CrCl) >60 mL/min.

METHODS

This was a retrospective review of CMV intermediate-risk liver, SPK, and SLK recipients with CrCl >60 mL/min transplanted January 2018 to June 2022 who received VGC 450 mg daily for prophylaxis. The primary outcome was incidence of CMV infection 6-months post-transplant.

RESULTS

Ninety-nine transplant recipients were included (79 liver, 11 SPK, 9 SLK). The primary outcome occurred in 13% of patients (liver 10%, SPK 36%, SLK 10%), including 1 case of CMV disease and 3 breakthrough infections. In addition, 6 patients experienced CMV infection between 6-months and 1-year. Recurrence occurred in 3 patients. There was no evidence of CMV resistance. Thirty patients experienced neutropenia within 1-year, 32 were prescribed granulocyte-colony stimulating factors, and 5 experienced thrombocytopenia. Two patients died due to graft-vs-host disease.

CONCLUSION AND RELEVANCE

Low-dose VGC prophylaxis led to comparable CMV infection rates at 6-months in CMV intermediate-risk liver and SLK recipients. However, as SPK recipients displayed higher rates of CMV infection, low-dose VGC should be avoided in this population.

Bilateral Cytomegalovirus Retinitis After Chimeric Antigen Receptor T-cell Therapy for B-cell Lymphoma

Cytomegalovirus (CMV) retinitis is commonly associated with immunosuppression and can cause irreversible vision loss. Chimeric antigen receptor T-cell (CAR-T) therapy has emerged as an effective cancer treatment option but requires immunosuppression, thereby increasing the possibility of acquiring opportunistic infections such as CMV. We present the case of a 76-year-old female with a history of hypertension and type 2 diabetes mellitus who initially presented with shortness of breath and was diagnosed with the activated B-cell subset of diffuse large B-cell lymphoma (DLBCL). She received multiple cycles of chemotherapy and experienced relapses with cardiac involvement. The patient developed vision loss in the right eye and was diagnosed with bilateral posterior vitritis. She underwent various treatments, including radiotherapy, systemic chemotherapy, cataract extraction, and vitrectomy. After CAR-T therapy, she developed bilateral CMV retinitis, confirmed through polymerase chain reaction testing and managed by valganciclovir. Overall, this case report describes the first reported case of bilateral CMV retinitis following CAR-T therapy for DLBCL. It emphasizes the need for early recognition and treatment of CMV retinitis to prevent permanent vision loss. The report also underscores the importance of regular ocular screening and consideration of prophylactic measures in patients undergoing CAR-T therapy.

Trough ganciclovir concentration as predictor of leukopenia in lung transplant recipients receiving valganciclovir prophylaxis

BACKGROUND

Valganciclovir is the first-line agent for Cytomegalovirus prophylaxis after lung transplantation. However, its use is associated with a relatively high risk of hematological toxicity. This study aimed to investigate the relationship between trough ganciclovir concentration and hematologic toxicity in lung transplantation patients receiving valganciclovir prophylaxis, and identify factors that affect ganciclovir pharmacokinetics in this population.

METHODS

This prospective observational study included 24 lung transplant patients receiving valganciclovir prophylaxis. The cutoff value of trough ganciclovir concentration was estimated using receiver operating characteristic analysis in leukopenia grade 3 and higher. Population pharmacokinetic analysis was performed using a nonlinear mixed-effects modeling program.

RESULTS

The trough ganciclovir concentration was significantly higher in the group with leukopenia grades 3 or higher than in the group with grades less than or equal to 2 (1605.7 ± 860.1 ng/mL [n = 3] vs. 380.5 ± 175.8 ng/mL (n = 21), p < .001). The cutoff value of trough ganciclovir concentration for predicting greater than or equal to grade 3 leukopenia was estimated as 872.0 ng/mL. Creatinine clearance and lung re-transplantation were found to have a significant impact on the total body clearance of valganciclovir. Ganciclovir clearance was decreased in patients with reduced creatine clearance or re-transplantation.

CONCLUSION

These results suggest that higher ganciclovir trough concentrations are associated with an increased risk of leukopenia grade 3 or higher, and that creatinine clearance and lung re-transplantation affected the pharmacokinetics of ganciclovir.

Reduced dosing versus full dosing valganciclovir for prophylaxis of cytomegalovirus in high-risk abdominal transplant recipients

BACKGROUND

Cytomegalovirus (CMV) is a common infection in abdominal transplant recipients (ATR). Prevention of CMV in the highest risk population (CMV IgG donor+/recipient-) is critical as CMV is associated with negative outcomes. Guideline recommended prophylactic valganciclovir dosing is 900 mg daily for 6 months in this population. However, reduced dosing strategies are utilized in practice.

METHODS

This single center, retrospective study in adult ATR compared full valganciclovir prophylactic dosing (900 mg daily for 6 months) to reduced dosing (900 mg daily for 3 months, then 450 mg daily for 3 months). The primary endpoint was incidence of CMV infection with viral load >1000 IU/mL. Secondary endpoints included incidence of CMV infection with viral load 200-1000 IU/mL, neutropenia, and leukopenia.

RESULTS

Incidence of CMV infection with viral load >1000 IU/mL (29% vs. 27%, p = 1) or CMV infection with viral load 200-1000 IU/mL (6% vs. 12%, p = .421) did not differ significantly between 68 ATR in reduced and full dosing groups, as well as incidence of leukopenia (94% vs. 97%, p = 1) and neutropenia (77% vs. 70%, p = .586).

CONCLUSIONS

There was no difference in the incidence of CMV infection, neutropenia, or leukopenia of the two dosing regimens, although time to CMV diagnosis was different.

Cytomegalovirus Disease as a Risk Factor for Invasive Fungal Infections in Liver Transplant Recipients under Targeted Antiviral and Antimycotic Prophylaxis

Cytomegalovirus (CMV) infection is the most common opportunistic infection that occurs following orthotopic liver transplantation (OLT). In addition to the direct infection-related symptoms, it also triggers an immunological response that may contribute to adverse clinical outcomes. CMV disease has been described as a predictor of invasive fungal infections (IFIs) but its role under an antiviral prophylaxis regimen is unclear.

METHODS

We retrospectively analyzed the medical records of 214 adult liver transplant recipients (LTRs). Universal antiviral prophylaxis was utilized in recipients with CMV mismatch; intermediate- and low-risk patients received pre-emptive treatment.

RESULTS

Six percent of patients developed CMV disease independent of their serostatus. The occurrence of CMV disease was associated with elevated virus load and increased incidence of leucopenia and IFIs. Furthermore, CMV disease was associated with higher one-year mortality and increased relapse rates within the first year of OLT.

CONCLUSIONS

CMV disease causes significant morbidity and mortality in LTRs, directly affecting transplant outcomes. Due to the increased risk of IFIs, antifungal prophylaxis for CMV disease may be appropriate. Postoperative CMV monitoring should be considered after massive transfusion, even in low-risk serostatus constellations. In case of biliary complications, biliary CMV monitoring may be appropriate in the case of CMV-DNA blood-negative patients.

Evaluating the Incidence and Risk Factors for Acute Cellular Rejection in a Steroid Sparing Liver Transplant Center

BACKGROUND

Corticosteroids has been the mainstay of immunosuppression (IMS) following liver transplant (LT). With the advent of more potent IMS, complete steroid withdrawal has become possible after LT. However, there is limited data regarding the incidence and risk factors for acute cellular rejection (ACR) in LT recipients on steroid sparing regimens.

OBJECTIVE

To identify the incidence and risk factors of ACR in LT recipients at an urban LT center utilizing a steroid-sparing IMS regimen.

METHODS

This was a single center retrospective study evaluating incidence of ACR in adults (>18 years) who received a LT between 01/01/2008 and 6/30/2019 at a steroid-sparing liver transplant center. Data between patients who had ACR and patients who did not were compared and risk factors were identified by multivariate logistic linear regression.

RESULTS

A total of 266 patients were included in this analysis, of which 18.4% experienced ACR within the first year of LT. Median time to first ACR was 134 (interquartile range [IQR]: 34-246) days. Black race (odds ratio [OR]: 4.39, P < 0.001), continued need for prednisone (OR: 2.80, P = 0.015) and cytomegalovirus (CMV) viremia (OR: 6.27, P < 0.001)) were independent risk factors for ACR. Tacrolimus use was associated with less ACR (OR: 0.33, P = 0.013).

CONCLUSION AND RELEVANCE

Steroid sparing regimens for IMS post-LT were not associated with an increased incidence of ACR when compared to reported ACR rates in literature. Potential risk factors for ACR include Black race, the use of prednisone maintenance IMS therapy, and CMV viremia.

Incidence and risk factors for the development of cytomegalovirus viremia in a steroid sparing liver transplant center

BACKGROUND

Cytomegalovirus (CMV) is a common opportunistic infection in patients after liver transplant (LT). Guidelines recommend 900mg daily of valganciclovir, however, valganciclovir commonly causes dose-dependent hematologic toxicities. Use of a low-dose valganciclovir (450mg) has been used to prevent these adverse effects, but the data regarding this dosing strategy is not as robust in a steroid sparing LT center.

METHODS

Retrospective chart review of adult LT recipients between January 1, 2008 and June 30, 2019. All patients received low-dose valganciclovir 450 mg PO daily for CMV prophylaxis. Primary outcome was the incidence of CMV viremia in LT recipients at 12 months post-LT. Secondary outcomes include time to CMV viremia, risk factors for the development of CMV viremia, and incidence of breakthrough CMV viremia while on valganciclovir prophylaxis.

RESULTS

A total of 266 patients were included. Overall, the majority were male (63.2%) and Caucasian (45.5%). The most common indication for transplant was decompensated cirrhosis (82%). The incidence of CMV at one year post-transplant was 7.9%. Independent risk factors included high risk status (OR 5.97, 95% CI 2.14-16.61, p = 0.001) as well as having an episode of rejection (OR 5.99, 95% CI 2.16-16.66, p = 0.001).

CONCLUSION

Low-dose valganciclovir can be effective in the prevention of CMV viremia in LT patients and may be a beneficial strategy for CMV prophylaxis in a steroid-sparing transplant center. Further studies may be needed to determine appropriate length of prophylaxis therapy for different risk groups. This article is protected by copyright. All rights reserved.

Safety of Valganciclovir 450 mg 3 Times Weekly for Cytomegalovirus Prophylaxis in Solid Organ Transplant Recipients Requiring Hemodialysis

Background

Valganciclovir is the most commonly used antiviral for cytomegalovirus (CMV) prophylaxis in solid organ transplant recipients. However, there are limited clinical outcomes-supported data available to guide valganciclovir dosing in patients on hemodialysis (HD). This study aimed to assess the safety of our institution's current dosing strategy of valganciclovir 450 mg 3 times weekly post-HD.

Methods

This was a single-center retrospective review of all adult nonkidney transplant recipients between May 2016 and June 2018. Patients with end-stage renal disease requiring HD for >28 days posttransplant receiving valganciclovir 450 mg 3 times weekly post-HD were matched with non-HD patients receiving valganciclovir prophylaxis dosed per renal function. The primary endpoints were incidence of leukopenia, neutropenia, and thrombocytopenia while on valganciclovir prophylaxis.

Results

A total of 465 nonkidney transplants were performed during the study period, with 37 patients included in the HD group who were matched to 111 control patients in the non-HD group. Liver transplant recipients comprised 84% and 72% of each group, with none being CMV D+/R-. The rates of leukopenia (51.4% vs 51.4%, P = 1.00), severe neutropenia (absolute neutrophil count <500 cells/µL, 15.8% vs 14.0%, P = .85), and thrombocytopenia (24.3% vs 20.7%, P = .64) were similar in both HD and non-HD groups. There were no cases of CMV infection while on valganciclovir prophylaxis in either group.

Conclusions

Valganciclovir 450 mg 3 times weekly was found to have similar rates of leukopenia, neutropenia, thrombocytopenia, and CMV infection in comparison to valganciclovir dosed per renal function in non-HD transplant recipients.

Pharmacokinetics, Pharmacodynamics, and Therapeutic Drug Monitoring of Valganciclovir and Ganciclovir in Transplantation

Ganciclovir and valganciclovir are first choice drugs for the prevention and treatment of cytomegalovirus infection and disease in solid organ and stem cell transplant recipients. Only a few studies on the pharmacokinetics and exposure/efficacy or exposure/safety relationships of ganciclovir and valganciclovir in transplant recipients have been published so far, and there are still controversies about the exposure parameter to use for therapeutic drug monitoring (TDM). We performed an extensive literature review of the clinical pharmacokinetics data, the exposure/effect relationships in terms of efficacy and safety, and the available tools for valganciclovir and ganciclovir TDM in adults and pediatrics transplant recipients. The pharmacokinetics of ganciclovir and valganciclovir is well described in adults and children, and a high interindividual variability is commonly observed. In contrast, the drug pharmacodynamics has been poorly described in adults and barely in children. The average 24-hour area under the concentration-time curve (AUC_0-24h ) seems to be the best predictor of efficacy and toxicity. The benefit of TDM remains controversial in adult patients but should be considered in children due to higher interindividual variability and lower probability of target attainment. Several bayesian estimators based on limited sampling strategies have been developed with this aim and may be used in clinical practice for the AUC-based individual dose adjustment of ganciclovir and valganciclovir.

Efficacy of low-dose valganciclovir in CMV R+ lung transplant recipients: a retrospective comparative analysis

Background

Cytomegalovirus (CMV) infection is extremely common after lung transplant and can be associated with significant morbidity and mortality. Current practice suggests the use of 900 mg daily of valganciclovir for CMV prophylaxis, but there is no literature assessing whether 450 mg daily of valganciclovir is sufficient in intermediate CMV risk lung transplant recipients. Therefore, we sought to assess the role of low-dose valganciclovir (LDV) versus high-dose valganciclovir (HDV) prophylaxis in intermediate-risk (R+) recipients.

Methods

We conducted a retrospective analysis on lung transplant recipients at the Norton Thoracic Institute in Phoenix, Arizona looking at intermediate-risk patients that received either valganciclovir 450 mg per day (LDV) or 900 mg/day (HDV). All patients were followed for 1 year post-transplant for incidence of CMV viremia. The primary outcome was the rate of CMV viremia as determined by a positive CMV polymerase chain reaction ([PCR] >2.7 log copies/mL). Secondary outcomes included rate of adverse events, acute cellular rejection, and mortality.

Results

The primary analysis included 103 patients (55 in the LDV group, 48 in the HDV group). In the LDV group, 9 patients (16.4%) developed CMV viremia compared to 4 (8.3%) in the HDV group (p=0.221) with no difference observed in adverse event rates between groups.

Conclusion

There was no statistical difference between groups for the primary outcome. However, the effect size demonstrated in this analysis may be of clinical relevance and valganciclovir 450 mg daily would not be recommended in intermediate risk lung transplant recipients at this time. To confirm our results, further prospective studies enrolling larger patient populations are necessary.

Risk Factors for Failure of Primary (Val)ganciclovir Prophylaxis Against Cytomegalovirus Infection and Disease in Solid Organ Transplant Recipients

Background

Rates and risk factors for cytomegalovirus (CMV) prophylaxis breakthrough and discontinuation were investigated, given uncertainty regarding optimal dosing for CMV primary (val)ganciclovir prophylaxis after solid organ transplantation (SOT).

Methods

Recipients transplanted from 2012 to 2016 and initiated on primary prophylaxis were followed until 90 days post-transplantation. A (val)ganciclovir prophylaxis score for each patient per day was calculated during the follow-up time (FUT; score of 100 corresponding to manufacturers’ recommended dose for a given estimated glomerular filtration rate [eGFR]). Cox models were used to estimate hazard ratios (HRs), adjusted for relevant risk factors.

Results

Of 585 SOTs (311 kidney, 117 liver, 106 lung, 51 heart) included, 38/585 (6.5%) experienced prophylaxis breakthrough and 35/585 (6.0%) discontinued prophylaxis for other reasons. CMV IgG donor+/receipient- mismatch (adjusted HR [aHR], 5.37; 95% confidence interval [CI], 2.63 to 10.98; P < 0.001) and increasing % FUT with a prophylaxis score <90 (aHR, 1.16; 95% CI, 1.04 to 1.29; P = .01 per 10% longer FUT w/ score <90) were associated with an increased risk of breakthrough. Lung recipients were at a significantly increased risk of premature prophylaxis discontinuation (aHR, 20.2 vs kidney; 95% CI, 3.34 to 121.9; P = .001), mainly due to liver or myelotoxicity.

Conclusions

Recipients of eGFR-adjusted prophylaxis doses below those recommended by manufacturers were at an increased risk of prophylaxis breakthrough, emphasizing the importance of accurate dose adjustment according to the latest eGFR and the need for novel, less toxic agents.