Tacrolimus exposure after liver transplantation in randomized controlled trials: too much for too long

Telemedicine based remote monitoring after liver transplantation: Feasible in a select group and a more stringent control of immunosuppression

Telemedicine gained interest in liver transplant patients but focused until now on the early post‐operative period. This prospective cohort study assessed feasibility, safety, and clinical beneficial effects of a telemedicine based remote monitoring program (TRMP) for the chronic follow‐up of adult liver transplant recipients. Between November 2017 and August 2019, a total of 87 of the 115 selected patients (76%) started the TRMP. Over the 2 years study period, none of the patients switched to standard follow‐up: 39/87 (45%) continued to do this autonomously and 48/87 (55%) stopped to report their data personally but communicated their lab values to the nurse. The other 28/115 (11%) patients who did not accept the TRMP continued the standard follow‐up. There was no difference in educational level between the three groups. Remote monitoring did not result in an increase in liver graft rejection and need of hospitalization. TRMP was associated with a higher number of tacrolimus level determinations and tacrolimus blood level concentrations could be kept lower. In conclusion, our results show that in patients with a stable clinical condition there is a high willingness to participate in TRMP and that this approach is safe. Remote monitoring allowed a stringent follow‐up of tacrolimus levels.

Liver transplantation: immunosuppression and oncology

PURPOSE OF REVIEW

Long-term survival of liver transplant recipients is threatened by increased rates of de-novo malignancy and recurrence of hepatocellular carcinoma (HCC), both events tightly related to immunosuppression.

RECENT FINDINGS

There is accumulating evidence linking increased exposure to immunosuppressants and carcinogenesis, particularly concerning calcineurin inhibitors (CNIs), azathioprine and antilymphocyte agents. A recent study including 219 HCC transplanted patients showed that HCC recurrence rates were halved if a minimization of CNIs was applied within the first month after liver transplant. With mammalian target of rapamycin (mTOR) inhibitors as approved immunosuppressants for liver transplant patients, pooled data from several retrospective studies have suggested their possible benefit for reducing HCC recurrence.

SUMMARY

Randomized controlled trials with sufficiently long follow-up are needed to evaluate the influence of different immunosuppression protocols in preventing malignancy after LT. Currently, early minimization of CNIs with or without mTOR inhibitors or mycophenolate seems a rational strategy for patients with risk factors for de-novo malignancy or recurrence of HCC after liver transplant. A deeper understanding of the immunological pathways of rejection and cancer would allow for designing more specific and safer drugs, and thus to prevent cancer after liver transplant.

Current strategies for immunosuppression following liver transplantation

BACKGROUND

New strategies for immunosuppression (IS) after liver transplantation (LTx) are in part responsible for the increased patient and graft survival seen over time. With a few basic exceptions-notably the continued use of steroids and calcineurin inhibitors (CNIs)-IS drugs and regimens being used today are different from those used 30 years ago. While graft loss due to acute or chronic rejection has become rare, the side effect burden of IS drugs exerts a significant toll on patients.

CONCEPTS/TRENDS

CNIs continue to form the backbone of IS regimens, although their use is hampered by nephrotoxicity and other adverse effects. Consequently, a variety of CNI reduction or withdrawal strategies have formed the basis of clinical trials or entered into clinical practice. These trials have included the use of everolimus, an mTOR inhibitor, and anti-interleukin-2 receptor antibodies. Basiliximab, as well as other lymphocyte nondepleting and depleting agents, have shown benefit in induction regimens.

SUMMARY

Along with steroid reduction or elimination, current strategies for IS after LTx continue to explore novel combinations of agents, with an aim toward striking a balance between diminution of rejection and the need for avoiding adverse effects of the IS drugs. Long-term maintenance strategies are also discussed in this review, as is development of tolerance and antibody-mediated rejection.

De novo sirolimus and reduced-dose tacrolimus versus standard-dose tacrolimus after liver transplantation: the 2000-2003 phase II prospective randomized trial

We studied whether the use of sirolimus with reduced-dose tacrolimus, as compared to standard-dose tacrolimus, after liver transplantation is safe, tolerated and efficacious. In an international multicenter, open-label, active-controlled randomized trial (2000-2003), adult primary liver transplant recipients (n=222) were randomly assigned immediately after transplantation to conventional-dose tacrolimus (trough: 7-15 ng/mL) or sirolimus (loading dose: 15 mg, initial dose: 5 mg titrated to a trough of 4-11 ng/mL) and reduced-dose tacrolimus (trough: 3-7 ng/mL). The study was terminated after 21 months due to imbalance in adverse events. The 24-month cumulative incidence of graft loss (26.4% vs. 12.5%, p=0.009) and patient death (20% vs. 8%, p=0.010) was higher in subjects receiving sirolimus. A numerically higher rate of hepatic artery thrombosis/portal vein thrombosis was observed in the sirolimus arm (8% vs. 3%, p=0.065). The incidence of sepsis was higher in the sirolimus arm (20.4% vs. 7.2%, p=0.006). Rates of acute cellular rejection were similar between the two groups. Early use of sirolimus using a loading dose followed by maintenance doses and reduced-dose tacrolimus in de novo liver transplant recipients is associated with higher rates of graft loss, death and sepsis when compared to the use of conventional-dose tacrolimus alone.

Reduced exposure to calcineurin inhibitors early after liver transplantation prevents recurrence of hepatocellular carcinoma

BACKGROUND & AIMS

Recurrence of hepatocellular carcinoma (HCC) is a major complication after liver transplantation (LT). The initial immunosuppression protocol may influence HCC recurrence, but the optimal regimen is still unknown.

METHODS

219 HCC consecutive patients under Milan criteria, who received an LT at 2 European centres between 2000 and 2010, were included. Median follow-up was 51 months (IQR 26-93). Demographic characteristics, HCC features, and immunosuppression protocol within the first month after LT were evaluated against HCC recurrence by using Cox regression.

RESULTS

In the explanted liver, 110 patients (50%) had multinodular HCC, and largest nodule diameter was 3±2.1cm. Macrovascular invasion was incidentally detected in 11 patients (5%), and microvascular invasion was present in 41 patients (18.7%). HCC recurrence rates were 13.3% at 3 years and 17.6% at 5 years. HCC recurrence was not influenced by the use/non-use of steroids and antimetabolites (p=0.69 and p=0.70 respectively), and was similar with tacrolimus or cyclosporine (p=0.25). Higher exposure to calcineurin inhibitors within the first month after LT (mean tacrolimus trough concentrations >10ng/ml or cyclosporine trough concentrations >300ng/ml), but not thereafter, was associated with increased risk of HCC recurrence (27.7% vs. 14.7% at 5 years; p=0.007). The independent predictors of HCC recurrence by multivariate analysis were: high exposure to calcineurin inhibitors defined as above (RR=2.82; p=0.005), diameter of the largest nodule (RR=1.31; p<0.001), microvascular invasion (RR=2.98; p=0.003) and macrovascular invasion (RR=4.57; p=0.003).

CONCLUSIONS

Immunosuppression protocols with early CNI minimization should be preferred in LT patients with HCC in order to minimize tumour recurrence.