Safety and efficacy of tenofovir alafenamide in liver transplant recipients: A single center experience.

BACKGROUND: Tenofovir disoproxil fumarate (TDF) is frequently used for treatment of and prophylaxis against reactivation of hepatitis B virus (HBV) after liver transplant (LT). Because TDF can lead to renal impairment and a decrease in bone mineral density (BMD), the prodrug tenofovir alafenamide (TAF) may be considered a viable alternative with fewer adverse effects. Only limited information is available about the use of TAF for LT recipients. We report a European single-center experience with TAF as treatment for LT patients. METHODS: This retrospective analysis involved 29 LT recipients receiving standard immunosuppressants (mainly calcineurin inhibitors). Demographic and clinical data were documented at baseline upon switch to TAF and at various time points thereafter. RESULTS: None of the patients experienced HBV reactivation after the switch to TAF. Liver and renal function remained stable. Drug levels of immunosuppressive agents did not change significantly after the switch. After 1 year, 22 patients were still taking TAF; two patients had been lost to follow-up; one patient had died; and four patients had discontinued therapy because of TAF-related adverse effects. No serious adverse effects were reported. CONCLUSIONS: Tenofovir alafenamide exhibits high antiviral efficacy and a good safety profile for LT recipients. Still, the safety and tolerability of TAF for organ transplant patients should be evaluated in larger cohorts.

The Effect of Immunosuppression on Coagulation After Liver Transplantation.

Everolimus (EVR) is a mammalian target of rapamycin (mTOR) inhibitor commonly used for immunosuppression (IS) after liver transplantation (LT). However, there are concerns about whether mTOR inhibitors may move the hemostatic balance toward a higher likelihood of thrombosis. The present study aimed to investigate potential coagulation disorders after the administration of EVR. We evaluated 54 patients after conversion to an EVR-based IS regimen (n = 26) and compared those patients with patients who were switched to extended-release tacrolimus (TAC) but had never received EVR (n = 28). At baseline and again at 1 month and 6 months after conversion, we measured international normalized ratio, activated partial thromboplastin time, and anticoagulation and fibrinolysis factors, and we performed rotational thromboelastometry (ROTEM). Data were analyzed with a Mann-Whitney U test, a repeated-measure analysis of variance, and a Fisher's exact test. Statistical significance was set at the level of P ≤ 0.05. Plasma levels of von Willebrand factor, fibrinogen, and factor VIII were significantly higher than baseline levels at 1 month and 6 months after conversion of IS to EVR (P < 0.001); plasma levels of protein C, protein S, and plasminogen also increased significantly (P < 0.001). ROTEM confirmed a significant increase in maximum clot firmness in EXTEM, INTEM, and FIBTEM assays (P < 0.001). In all assays, maximum lysis was significantly lower than baseline levels at 1 month and 6 months after conversion to EVR. Patients converted to IS with extended-release TAC exhibited no significant changes in coagulation variables. Retrospective analysis showed a significantly higher incidence of thromboembolic complications among patients treated with EVR-based IS than among those treated with extended-release TAC (P < 0.01). In conclusion, the administration of EVR after LT seems to modify hemostasis to a procoagulant state. Thrombophilia screening before conversion may determine which patients will benefit from conversion to EVR-based IS.

Daclatasvir, Simeprevir and Ribavirin as a Promising Interferon-Free Triple Regimen for HCV Recurrence after Liver Transplant.

BACKGROUND: Recurrent hepatitis C infection after liver transplantation (LT) is associated with lower rates of graft and patient survival. METHODS: Here we describe the first use of daclatasvir, simeprevir, and ribavirin (RBV) as an all-oral triple regimen administered to 6 liver transplant recipients with recurrent hepatitis C, one with GT 1a and 5 with GT 1b. All patients were treated for 24 weeks. Trough levels of immunosuppression, laboratory measures, and potential adverse effects were closely monitored. RESULTS: For all patients, viral load became undetectable between treatment weeks 4 and 12. One patient experienced a viral breakthrough at the 10th week of treatment; this was associated with the selection of resistance-associated variants (D168Y in NS3 and ΔP32 in NS5A). For the other 5 patients, end-of-treatment response and for 4 patients SVR24 was achieved. Viremia recurred in one patient 4 weeks after the end of treatment, which was again associated with the selection of resistance-associated variants (D168V in NS3 and ΔP32 in NS5A). Clinical measures of liver function improved substantially for all patients. Adverse events were few and limited to moderate anemia caused by RBV. Importantly, adjustments to the immunosuppressant dosage were not required. CONCLUSIONS: The described regimen appears to be safe and effective for liver transplant patients and will be a promising treatment regimen for post-LT patients.

Comparison of Three Cellular Assays to Predict the Course of CMV Infection in Liver Transplant Recipients.

To estimate protection from cytomegalovirus (CMV) replication after solid organ transplantation, CMV serology has been considered insufficient and thus CMV immunity is increasingly assessed by cellular in vitro methods. We compared two commercially available IFN-γ ELISpot assays (T-Track CMV and T-SPOT.CMV) and an IFN-γ ELISA (QuantiFERON-CMV). Currently, there is no study comparing these three assays. The assays were performed in 56 liver transplant recipients at the end of antiviral prophylaxis and one month thereafter. In CMV high- or intermediate-risk patients the two ELISpot assays showed significant correlation (p < 0.0001, r > 0.6) but the correlation of the ELISpot assays with QuantiFERON-CMV was weaker. Results of both ELISpot assays were similarly predictive of protection from CMV-DNAemia ≥500 copies/mL [CMV pp65 T-SPOT.CMV at the end of prophylaxis: area under curve (AUC) = 0.744, cut-off 142 spot forming units (SFU), sensitivity set to 100%, specificity 46%; CMV IE-1 T-Track CMV at month 1: AUC = 0.762, cut-off 3.5 SFU, sensitivity set to 100%, specificity 59%]. The QuantiFERON-CMV assay was inferior, reaching a specificity of 23% when setting the sensitivity to 100%. In conclusion, both CMV-specific ELISpot assays appear suitable to assess protection from CMV infection/reactivation in liver transplant recipients.

Daily low-dose tacrolimus is a safe and effective immunosuppressive regimen during telaprevir-based triple therapy for hepatitis C virus recurrence after liver transplant.

BACKGROUND: Graft loss because of hepatitis C virus recurrence is a serious problem after liver transplantation (LT), and the response to pegylated interferon (PEG-IFN) and ribavirin (RBV) is poor. The significantly better response rates achieved with telaprevir (TVR)-based triple therapy have led to better graft and patient survival rates, but severe drug interactions may limit the usefulness of this therapy for LT patients. We report our single-center experience with a specially developed protocol that involved administering a low daily dose of tacrolimus (TAC) to a cohort of 17 patients with a recurrence of hepatitis C virus genotype 1 after LT. METHODS: Patients were treated with TVR, PEG-IFN, and RBV for 12 weeks, followed by 12 or 36 weeks of dual therapy with PEG-IFN and RBV. After TVR administration was initiated, the TAC dosage was skipped until trough levels began to decline; it was then administered at a dose of 0.1 mg once or twice daily. Tacrolimus trough levels and laboratory values were closely monitored during the TVR phase. RESULTS: Deviations in trough levels were avoided, thus preventing any clinically evident renal toxicity related to TAC. In addition, histologic studies performed at the end of therapy showed that no rejection episodes had occurred. All patients tolerated the medication. Sustained virologic response was documented for 10 of 17 patients (58%) 24 weeks after end of treatment. CONCLUSION: In conclusion, substantial dose reduction and daily administration of low doses of TAC compose a safe and efficient immunosuppressive regimen during TVR-based triple therapy.

Management of telaprevir-based triple therapy for hepatitis C virus recurrence post liver transplant.

AIM: To characterize management of telaprevir (TVR)-based triple therapy of hepatitis C virus (HCV) reinfection after liver transplantation (LT). METHODS: We retrospectively analyzed safety and efficacy of telaprevir - based triple therapy in a single center cohort of 19 patients with HCV genotype (GT) 1 recurrence after LT, with respect to factors possibly predicting sustained viral response (SVR) or non-SVR. All patients were treated with TVR, pegylated (PEG) and ribavirine (RBV) for 12 wk followed by a dual phase with PEG/RBV for 12 wk in 7 patients and for 36 wk in 5 patients. RESULTS: In total 11/19 (58%) of patients achieved a sustained response. All (11/11) SVR patients showed a rapid viral response at treatment weeks 4 and 11/14 rapid virological response (RVR) patients achieved SVR. Notably, all (7/7) patients who completed 48 wk of therapy and 80% (4/5) patients who completed 24 wk of therapy achieved SVR24. Treatment failure was significantly (P > 0.049) more frequent in GT1a infection (5/7) compared to GT1b (3/12) infection and was associated with emergence of resistance-associated mutations in the NS3 protease domain. Bilirubin level at baseline is also related to SVR (P > 0.030). None of the patients had to discontinue treatment due to side effects. CONCLUSION: RVR, GT and bilirubin are clearly related to achievement of SVR. Providing a thorough patient selection and monitoring, a full course of TVR-based triple therapy in LT patients is feasible and achieves high SVR rates.