Induction therapy with rabbit antithymocyte globulin versus basiliximab after kidney transplantation: a health economic analysis from a German perspective

The use of lymphocyte-depleting antibodies in specific populations of kidney transplant recipients: A systematic review and meta-analysis

BACKGROUND

Recommendations of the use of antibody induction treatments in kidney transplant recipients (KTR) are based on moderate quality and historical studies. This systematic review aims to reevaluate, based on actual studies, the effects of different antibody preparations when used in specific KTR subgroups.

METHODS

We searched MEDLINE and CENTRAL and selected randomized controlled trials (RCT) and observational studies looking at different antibody preparations used as induction in KTR. Comparisons were categorized into different KTR subgroups: standard, high risk of rejection, high risk of delayed graft function (DGF), living donor, and elderly KTR. Two authors independently assessed the risk of bias.

RESULTS

Thirty-seven RCT and 99 observational studies were finally included. Compared to anti-interleukin-2-receptor antibodies (IL2RA), anti-thymocyte globulin (ATG) reduced the risk of acute rejection at two years in standard KTR (RR 0.74, 95%CI 0.61-0.89) and high risk of rejection KTR (RR 0.55, 95%CI 0.43-0.72), but without decreasing the risk of graft loss. We did not find significant differences comparing ATG vs. alemtuzumab or different ATG dosages in any KTR group.

CONCLUSIONS

Despite many studies carried out on induction treatment in KTR, their heterogeneity and short follow-up preclude definitive conclusions to determine the optimal induction therapy. Compared with IL2RA, ATG reduced rejection in standard-risk, highly sensitized, and living donor graft recipients, but not in high DGF risk or elderly recipients. More studies are needed to demonstrate beneficial effects in other KTR subgroups and overall patient and graft survival.

Evidence of Interleukin-2-Receptor-Antibody Induction in Low-Risk Living Donor Kidney Transplantation: A Single-Center Pilot Study

BACKGROUND

The recommended standard immunosuppressive therapy for renal transplant recipients comprises an initial induction therapy mainly with an interleukin-2-receptor antibody (IL2-RA) and a triple maintenance therapy. With tacrolimus and mycophenolate acid it is unknown whether IL2-RA application affects the short- and long-term results. This question is addressed in the present analysis.

METHODS

From July 2007 to June 2019 a total of 127 living donor kidney transplant recipients meeting the center-specific definition of immunologic low risk situation (first transplantation, HLA-mismatch ≤3, panel reactive antibody ≤10%) were identified. In 83 recipients with a first-degree relationship to the donor we omitted the IL2-RA induction (IL2-RA-). The remaining 44 recipients, mostly not first-degree relatives, served as controls (IL2-RA+). Biopsy-proven acute rejection and long-term patient and graft survival rates were compared.

RESULTS

Biopsy-proven acute rejection rates after 3 months were similar in both groups with 4.8% (IL2-RA-) vs 13.7% (IL2-RA+; P = .0937), including borderline rejection rates of 18.0% (IL2-RA-) vs 18.3% (IL2-RA+; P = 1.000), respectively. Ten-year long-term survival rates were comparable between the IL2-RA- and the IL2-RA+ group with 95.6% vs 93.5% (patient survival; P = .5465) and 92.1% vs 90.6% (death-censored graft survival; P = .8893).

CONCLUSION

For low-risk living donor kidney transplant recipients with first-degree relationship to the donor, it is safe to omit induction therapy with IL2-RA.

The use of induction therapy in liver transplantation is highly variable and is associated with posttransplant outcomes

The use of induction immunosuppression in liver transplantation (LT) remains controversial. This was a retrospective cohort study of adult, first-time liver-alone recipients (N = 69 349) at 114 US centers between 2005 and 2018 using data from the United Network for Organ Sharing. The comparative effectiveness of nondepleting and depleting induction (NDI and DI) was assessed. Overall, 27% of recipients received induction with 65.7% of the variance in the receipt of induction being attributed to transplant center alone. NDI and DI were associated with a lower risk of death/graft failure compared to no induction (adjusted hazard ratio 0.90 [95% confidence interval (CI): 0.86-0.95] and 0.91 [95% CI: 0.85-0.97], respectively; P < .001). In nondialysis recipients at the mean transplant estimated glomerular filtration rate (eGFR), NDI was associated with an adjusted gain in eGFR by 6 months of +3.8 mL/min per 1.73 m² and DI of +3.33 mL/min per 1.73 m² compared to no induction (P < .001). Recipients with lower eGFR at LT had greater predicted improvement in eGFR (interaction P < .001). Only NDI was associated with a reduced risk of acute rejection in the first year post-LT (odds ratio 0.87, 95% CI: 0.8-0.94). Significant variability in induction practices exists, with center being a major determinant. The absolute incremental benefits of NDI and DI over no induction were small.

Low Total Dose of Anti-Human T-Lymphocyte Globulin (ATG) Guarantees a Good Glomerular Filtration Rate after Liver Transplant in Recipients with Pretransplant Renal Dysfunction

We aimed to evaluate the safety and efficacy of low doses of anti-T-lymphocyte globulin (ATG)-based immunosuppression in preserving renal function and preventing liver rejection in liver transplant (LT) recipients with pretransplant renal dysfunction. We designed a prospective single-center cohort study analyzing patients with pre-LT renal dysfunction defined as eGFR<60 mL/min/1.73m2, who underwent induction therapy with ATG (ATG group, n=20). This group was compared with a similar retrospective cohort treated with basiliximab (BAS group, n=20). An economic analysis between both induction therapies was also undertaken. In the ATG group, 45% and 50% of patients had recovered their renal function without acute cellular rejection (ACR) episodes at day 7 and 1 month after LT, respectively, versus 40% and 55% of patients in the BAS group (p=1). Renal function improved in both groups over time and no differences between groups were observed regarding one-year eGRF and one-year probability of ACR. Cost per patient of the ATG course was 403€ (r: 126-756) versus 2,524€ of the basiliximab course (p=0.001). In conclusion, induction with low dose of ATG or basiliximab in patients with pretransplant renal dysfunction is a good strategy for preserving posttransplant renal function; however the use of low-dose ATG resulted in a substantial reduction in drug costs. This trail is registered with ClinicalTrials.gov number: NCT01453218.

Does Rabbit Antithymocyte Globulin (Thymoglobuline®) Have a Role in Avoiding Delayed Graft Function in the Modern Era of Kidney Transplantation?

Delayed graft function (DGF) increases the risk of graft loss by up to 40%, and recent developments in kidney donation have increased the risk of its occurrence. Lowering the risk of DGF, however, is challenging due to a complicated etiology in which ischemia-reperfusion injury (IRI) leads to acute tubular necrosis. Among various strategies explored, the choice of induction therapy is one consideration. Rabbit antithymocyte globulin (rATG [Thymoglobuline]) has complex immunomodulatory effects that are relevant to DGF. In addition to a rapid and profound T-cell depletion, rATG inhibits leukocyte migration and adhesion. Experimental studies of rATG have demonstrated attenuated IRI-related tissue damage in reperfused tissues, consistent with histological evidence from transplant recipients. Starting rATG intraoperatively instead of postoperatively can improve kidney graft function and reduce the incidence of DGF. rATG is effective in preventing acute rejection in kidney transplant recipients at high immunological risk, supporting delayed calcineurin inhibitor (CNI) introduction which protects the graft from early insults. A reduced rate of DGF has been reported with rATG (started intraoperatively) and delayed CNI therapy compared to IL-2RA induction with immediate CNI in patients at high immunological risk, but not in lower-risk patients. Overall, induction with rATG induction is the preferred choice for supporting delayed introduction of CNI therapy to avoid DGF in high-risk patients but shows no benefit versus IL-2RA in lower-risk individuals. Evidence is growing that intraoperative rATG ameliorates IRI, and it seems reasonable to routinely start rATG before reperfusion.