Risk Assessment of Neutropenia during Low-Dose Valganciclovir Prophylaxis for Heart Transplant Recipients.

The aim of this study was to investigate whether low-dose valganciclovir (VGCV) prophylaxis for cytomegalovirus (CMV) infection increased the risk of developing neutropenia in heart transplant recipients (HTRs). Forty-three HTRs receiving VGCV were divided into two groups: those who received VGCV prophylaxis (n = 22) and those who did not (n = 21). Neutropenia was defined as an absolute neutrophil count ˂1500/µL and was monitored for approximately one year post-transplantation. In the prophylaxis group, 77.3% (17/22) of HTRs experienced neutropenia, which was significantly higher than that in the no prophylaxis group (42.9% [9/21], p = 0.031). No significant differences in the duration of VGCV administration and cumulative dose up to the first neutropenia episode were observed between the groups. Meanwhile, the cumulative dose of mycophenolate mofetil was significantly higher in the prophylaxis group than in the no prophylaxis group (p = 0.018); the daily maintenance dose and regularly measured area under the concentration-time curve (AUC) of mycophenolic acid did not significantly differ between groups. In conclusion, the risk of developing neutropenia was higher in HTRs receiving low-dose VGCV prophylaxis than it was in those not receiving prophylaxis, probably not attributed to dosing period and cumulative dose of VGCV until the onset of neutropenia.

Discontinuation of oral amphotericin B therapy does not influence the pharmacokinetics of tacrolimus in heart transplant patients.

OBJECTIVE: Amphotericin B (AMPH-B) is used to prevent opportunistic infections associated with immunosuppressive therapy after heart transplantation (HTx), while the blood concentrations of tacrolimus (TAC) are carefully controlled. Although AMPH-B has the potential to inhibit TAC metabolism in in vitro studies, its interaction with clinically used AMPH-B oral suspension has not been investigated. In the present study, we examined whether oral AMPH-B therapy influences the pharmacokinetics of TAC in HTx patients. MATERIALS AND METHODS: A retrospective study was performed at the National Cerebral and Cardiovascular Center in Japan. All patients with HTx enrolled in the study received standard triple-drug immunosuppression therapy including the regular release of TAC, mycophenolate mofetil, and prednisolone as well as prophylactic therapy with AMPH-B oral suspension. Patient characteristics and clinical laboratory data were collected from the electronic medical record system. Blood concentrations of TAC were used for pharmacokinetic analysis. RESULTS: A total of 14 patients were enrolled in the study. There were no statistically significant differences in the variables except for serum creatinine levels and eGFR before and after discontinuation of oral AMPH-B therapy. The dose and trough concentrations of TAC and the area under the time-concentration curve and apparent oral clearance calculated from its concentrations were not influenced by discontinuation of AMPH-B treatment. CONCLUSION: The prophylactic treatment with AMPH-B oral suspension did not influence the pharmacokinetics of TAC and was demonstrated as a safe and easy method to prevent early post-HTx fungal infection.

Influence of Induction Therapy Using Basiliximab With Delayed Tacrolimus Administration in Heart Transplant Recipients　- Comparison With Standard Tacrolimus-Based Triple Immunosuppression.

BACKGROUND: Appropriate indications and protocols for induction therapy using basiliximab have not been fully established in heart transplant (HTx) recipients. This study elucidated the influence of induction therapy using basiliximab along with delayed tacrolimus (Tac) initiation on the outcomes of high-risk HTx recipients.Methods and Results:A total of 86 HTx recipients treated with Tac-based immunosuppression were retrospectively reviewed. Induction therapy was administered to 46 recipients (53.5%) with impaired renal function, pre-transplant sensitization, and recipient- and donor-related risk factors (Induction group). Tac administration was delayed in the Induction group. Induction group subjects showed a lower cumulative incidence of acute cellular rejection grade ≥1R after propensity score adjustment, but this was not significantly different (hazard ratio [HR]: 0.63, 95% confidence interval [CI]: 0.37-1.08, P=0.093). Renal dysfunction in the Induction group significantly improved 6 months post-transplantation (P=0.029). The cumulative incidence of bacterial or fungal infections was significantly higher in the Induction group (HR: 10.6, 95% CI: 1.28-88.2, P=0.029). CONCLUSIONS: These results suggest that basiliximab-based induction therapy with delayed Tac initiation may suppress mild acute cellular rejection and improve renal function in recipients with renal dysfunction, resulting in its non-inferior outcome, even in high-risk patients, when applied to the appropriate recipients. However, it should be carefully considered in recipients at a high risk of bacterial and fungal infections.

Effect of Therapeutic Modification on Outcomes in Heart Transplantation Over the Past Two Decades　- A Single-Center Experience in Japan.

BACKGROUND: During these 2 decades (1999-2019), many therapeutic strategies have been developed in the field of heart transplant (HTx) to improve post-HTx outcomes. In the present study, 116 consecutive HTx adults between 1999 and 2019 were retrospectively reviewed to evaluate the influences of a therapeutic modification on post HTx outcomes.Methods and Results:Patient survival, functional status and hemodynamics after HTx and modification of therapeutic strategies were reviewed. The overall cumulative survival rate at 10 and 20 years post-HTx was 96.4 and 76.7%, respectively. There were no significant differences in survival rate or exercise tolerance after HTx between extracorporeal and implantable continuous flow-LVAD. Post-HTx patient survival in patients, irrespective of the donor risk factors such as donor age, low LVEF, history of cardiac arrest, was equivalent across cohorts, while longer TIT and higher inotrope dosage prior to procurement surgery were significant risk factors for survival. In 21 patients given everolimus (EVL) due to renal dysfunction, serum creatinine significantly decreased 1 year after initiation. In 22 patients given EVL due to transplant coronary vasculopathy (TCAV), maximum intimal thickness significantly decreased 3 years after initiation. CONCLUSIONS: The analysis of a 20-year single-center experience with HTx in Japan shows encouraging improved results when several therapeutic modifications were made; for example, proactive use of donor hearts declined by other centers and the use of EVL in patients with renal dysfunction and TCAV.

Drug interactions between tacrolimus and clotrimazole troche: a data mining approach followed by a pharmacokinetic study.

PURPOSE: This study investigated the effects of clotrimazole troche on the risk of transplant rejection and the pharmacokinetics of tacrolimus. METHODS: The data mining approach was used to investigate whether the use of clotrimazole increased the risk of transplant rejection in patients receiving tacrolimus therapy. Patient data were acquired from the US Food and Drug Administration's Adverse Event Reporting System (FAERS) from the first quarter of 2004 to the end of 2017. Next, we retrospectively investigated the effect of clotrimazole troche on tacrolimus pharmacokinetics in seven patients who underwent heart transplantation between March and December 2017. RESULTS: The FAERS subset data indicated a significant association between transplant rejection and tacrolimus with clotrimazole [reporting odds ratio 1.92, 95% two-sided confidence interval (95% CI) 1.43-2.58, information component 0.81, 95% CI 0.40-1.23]. The pharmacokinetic study demonstrated a significant correlation between trough concentration (C0) and area under the concentration-time curve of tacrolimus after discontinuation of clotrimazole (R2 = 0.60, P < 0.05) but not before its discontinuation. Furthermore, the median clearance/bioavailability of tacrolimus after discontinuation of clotrimazole was 2.2-fold greater than that before its discontinuation (0.27 vs. 0.59 L/h/kg, P < 0.05). The median C0 decreased from 10.7 ng/mL on the day after discontinuation of clotrimazole to 6.5 ng/mL at 1 day and 5.3 ng/mL at 2 days after its discontinuation. CONCLUSION: Immediate dose adjustments of tacrolimus may be beneficial to avoid transplant rejection when clotrimazole troche is added or discontinued.

De novo malignancy in heart transplant recipients: A single center experience in Japan.

BACKGROUND: Because of aggressive immunosuppression, heart transplant recipients have a high risk of de novo malignancy, which is a major cause of death and worse prognosis, regardless of the type. However, the impact of de novo malignancy on Japanese heart transplant recipients is unknown. METHODS: We analyzed 103 Japanese heart transplant recipients over 18-years-old at the time of transplantation between April 1999 and April 2017. Patient characteristics and prognosis were compared between heart transplant recipients with or without de novo malignancy after heart transplantation (HTx). Additionally, univariate and multivariate analyses for the risk factors of de novo malignancy after HTx were performed. RESULTS: De novo malignancy developed in 7 patients (6.8%; post-transplant lymphoproliferative disorders, n=3; Bowen's disease, n=1; colon cancer, n=2; bladder cancer, n=1). Follow-up time and previous antibody mediated rejection (AMR)≥grade 1 were risk factors of de novo malignancy after HTx in multivariate analysis (OR: 1.19, 95% CI: 1.00-1.42, p=0.043; and OR: 10.7, 95% CI: 1.37-83.68, p=0.038, respectively). History of malignancy was a potential risk factor, albeit not significant (OR: 23.05, 95% CI: 0.99-534.53, p=0.071). The survival rates in patients with de novo malignancy was significantly lower than in those without de novo malignancy (3-year survival rate: 100% versus 67%, p=0.0025). CONCLUSIONS: Long follow-up time and previous AMR≥grade 1 were risk factors of de novo malignancy after HTx. Japanese heart transplant recipients with de novo malignancy have worse prognosis; therefore, screening examinations are important for early diagnosis.