Tacrolimus versus cyclosporine after lung transplantation: a prospective, open, randomized two-center trial comparing two different immunosuppressive protocols

CLINICAL LUNG AND HEART/LUNG TRANSPLANTATION

Tacrolimus versus Cyclosporine after Lung Transplantation: A Prospective, Open, Randomized Two-Center Trial Comparing Two Different Immunosuppressive Protocols Hendrik Treede, MD,a Walter Klepetko, MD,b Hermann Reichenspurner, MD, PhD,a Andreas Zuckermann, MD,b Bruno Meiser, MD,a Tudor Birsan, MD,b Wilfried Wisser, MD,b Bruno Reichert, MD,a and the Munich and Vienna Lung Transplant Group Background: The need for better immunosuppressive protocols after lung transplantation led us to investigate tacrolimus (Tac) in combination with mycophenolate mofetil (MMF) and steroids or cyclosporine (CsA) in combination with MMF and steroids in a prospective, open, randomized trial after lung transplantation. Methods: Between September 1997 and April 1999, 50 lung transplant recipients were randomized to receive either Tac (n ⫽ 26) or CsA (n ⫽ 24) in combination with MMF and steroids. All patients underwent induction therapy with rabbit antithymocyte globulin (ATG) for 3 days. Freedom from acute rejection (AR), patient survival, infection episodes, and side effects were monitored. Results: There was no difference in patient demographics between the two groups. Sixmonth and 1-year survival was similar (84.6% and 73.1% in the Tac group vs 83.3% and 79.2% in the CsA group). Freedom from AR at 6 months and 1 year after lung transplantation was slightly higher in the Tac group (57.7% and 50% vs 45.8% and 33.3%, p ⫽ not significant [n.s.]), whereas the number of treated rejection episodes per 100 patient days in the Tac group was significantly lower (0.225 vs 0.426, p ⬍ .05). Four patients in the CsA group had to be switched to Tac. Two patients in the CsA group had to be retransplanted. Incidence of infections was similar in both groups with a trend toward more fungal infections in the Tac group (n ⫽ 7 vs n ⫽ 1, p ⫽ n.s.). Conclusions: The combination of Tac and MMF seems to have slightly higher immunosuppressive potential compared with CsA and MMF. The effectiveness of Tac as a rescue agent is not paralleled with undue signs of overimmunosuppression. J Heart Lung Transplant 2001;20:511–517. From the aLudwig-Maximilians-University, Munich, Germany; and bUniversity of Vienna, Vienna, Austria Presented at the annual meeting of the International Society for Heart and Lung Transplantation, San Francisco, CA, April 1999. Submitted March 14, 2000; accepted January 16, 2001. Reprint requests: Hermann Reichenspurner, MD, Department of Cardiac Surgery, University Hospital Grosshadern, Mar-

chioninistrasse 15, D-81377 Munich, Germany. Telephone: ⫹49-89-7095-3450. Fax: ⫹49-89-7095-3465. E-mail: hcr@hch. med.uni-muenchen.de Copyright © 2001 by the International Society for Heart and Lung Transplantation. 1053-2498/01/$–see front matter PII S1053-2498(01)00244-3

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ince the first lung transplantation in Toronto in 1986 much effort has been made to improve patient survival rates by reducing the incidence of rejection episodes and infections after lung transplantation. Nevertheless, the long-term outcome is worse when compared with other procedures such as heart or kidney transplantation. Actual ISHLT statistics have reported 1- and 3-year patient survival rates of 72.4% and 55.7%, respectively, after lung transplantation for the period between 1995 and 1998.1 Obliterative bronchiolitis (OB) is still the limiting factor for long-term survival and quality of life reflecting the need for better immunosuppressive regimens. Randomized studies conducted at the University of Pittsburgh have demonstrated a lower incidence of acute rejection episodes and a lower rate of OB for patients treated with tacrolimus (Tac) compared with cyclosporine (CsA) when combined with azathioprine (Aza).2–5 Studies at our center and the University of California showed even lower rates of acute rejection (AR) after lung transplantation for tacrolimus combined with mycophenolate mofetil (MMF), offering a similar safety profile.6,21 The positive effect of MMF was also demonstrated after heart transplantation.7 In the present study we report the results of a prospective, open, randomized, two-center trial comparing two novel immunosuppressive protocols after lung transplantation: Tac in combination with MMF and steroids versus CsA in combination with MMF and steroids. The aim of the study was to compare the efficacy and safety of both immunosuppressive protocols in a relatively small patient population to obtain data that could justify an extensive multi-center trial, thus fulfilling all requirements of a statistically proper sample size estimation. Therefore, the statistical power of the present study is relatively low, and the predictive value is limited. For assessment of efficacy, freedom from AR was the primary end-point. Secondary end-points were infections, patient survival rates, and side effects.

PATIENTS AND METHODS Patient Population Between September 1997 and April 1999, 50 lung transplant recipients were randomized to receive either Tac (n ⫽ 26) or CsA (n ⫽ 24) in combination with MMF and steroids. Randomization was performed in a 1:1 fashion with regard to a similar distribution of cytomegalovirus (CMV) mismatches (D⫹/R⫺) in both groups. Informed consent was obtained from each patient and the study was ap-

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TABLE I Demographic and baseline characteristics of lung transplant recipients Cyclosporine ⴙ Tacrolimus ⴙ mycophenolate mycophenolate mofetil mofetil (n ⴝ 26) (n ⴝ 24) Age (years) Mean Range

47 ⫾ 13 24–66

53 ⫾ 8 39–65

Male (%)

42

65

45.8 20.8 8.4 4.2 12.6

23.1 61.5 3.8 0 3.8

4.2

0

0 4.2

3.8 3.8

Diagnosis (%) Pulmonary fibrosis Emphysema Cystic fibrosis Lymphangiomyomatosis Pulmonary hypertension Obliterative bronchiolitis after bone marrow transplantation Sarcoidosis ␣-AT-deficiency Transplantation (%) Single lung Double lung Median follow-up (days)

42 58

50 50

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525

proved by an ethics committee (institutional review board) under consideration of the Declaration of Helsinki. Details of the recipient cohorts are shown in Table I. The two treatment groups were no different with regard to age, gender, diagnosis, and transplant procedure.

Surgical Procedures Forty-six percent (n ⫽ 23) of the transplants were single-lung procedures performed through a lateral thoracotomy, and 54% (n ⫽ 27) were double-lung procedures performed through a bilateral thoracotomy in a sequential mode using subsequent singlelung ventilation.

Immunosuppressive Regimen Patients in the Tac group received intravenous tacrolimus at a dose of 0.05 mg/kg per day immediately after surgery, and were then switched to oral tacrolimus at a dose of 0.1 to 0.3 mg/kg per day after extubation. Target whole-blood trough levels were 12 to 15 ng/ml (immunoflourescence absorption method). Patients in the CsA group also received

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intravenous CsA immediately after surgery at a dose of 2 mg/kg per day. After extubation they were switched to oral CsA at a dose of 3 to 5 mg/kg per day with target whole-blood trough levels of 250 to 300 ng/ml (monospecific, Syva method, Behring assay). MMF was initiated via a nasogastric tube at a dose of 2 g/day and was switched to oral administration after extubation. Dose adjustments were done in the presence of clinical side effects (e.g., leuko- or thrombopenia, gastrointestinal symptoms, etc.). Prednisone was started in both groups at a postoperative dose of 0.3 mg/kg per day and tapered to 0.15 mg/kg per day within the first 6 weeks after transplantation. All patients received induction therapy with rat antithymocyte globulin (RATG; Pasteur Merieux MSD, Leimen, Germany) for the first 3 post-operative days.

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FIGURE 1 Survival rates after pulmonary

transplantation. Survival data in the CsA group include 2 re-transplanted patients and 4 patients switched to Tac.

Diagnosis of Acute Rejection Daily chest X-ray and daily cytoimmunologic monitoring8 of the peripheral blood for the first 3 post-operative weeks and weekly pulmonary function tests helped to detect acute rejection episodes. We used cytoimmunologic monitoring as a wellestablished method combining morphologic quantitation of activated lymphocytes and immunoblasts with immunophenotyping of peripheral blood to differentiate between rejection and infection. Transbronchial biopsy was performed in cases in which deterioration was evident by chest X-ray or pulmonary function testing. Diagnosis of acute rejection was based on histologic or clinical signs, such as chest X-ray or pulmonary function tests in combination with an observed activation within the cytoimmunologic monitoring and required exclusion of any other complication (e.g., infection) and a positive response to anti-rejection therapy.

Anti-Rejection Therapy In case of diagnosis of acute rejection, bolus treatment with methylprednisolone was administered at a dose of 500 mg/day for 3 to 5 consecutive days. Resistant rejections were treated with a second bolus of methylprednisolone. Steroid-resistant rejections required a switch to the alternative immunosuppressive regimen.

Infection Prophylaxis All patients received infection prophylaxis with intravenous antibiotics started intraoperatively. A CMV prophylaxis with ganciclovir was administered

for a period of 3 months. In case of positive microbiologic findings in the explanted lungs the antibiotic prophylaxis was adapted to the anti-biogram.

Statistical Analysis Actuarial survival and freedom from event curves were calculated by Kaplan–Meier analysis and compared statistically using the log-rank test. Group mean values were compared using Student’s t-test.

RESULTS Follow-Up Median follow-up was 525 days in the Tac/MMF group and 511 days in the CsA/MMF group. Follow-up was calculated until day of recent examination or death or re-transplantation or switch of immunosuppressive regimen. Calculation of patient survival time included re-transplanted and switched patients (intent-to-treat analysis). Follow-up was complete in all patients.

Survival Rates Six-month and 1-year survival rates were 84.6% and 73.1% in the Tac/MMF group versus 83.3% and 79.2% in the CsA/MMF group, respectively (p ⫽ n.s.; Figure 1). Causes of death were sepsis (n ⫽ 3), fungal infections (n ⫽ 2), tuberculosis (n ⫽ 1), intracerebral bleeding (n ⫽ 1), and CMV pneumonia (n ⫽ 1) in the Tac/MMF group. Causes of death in the CsA/MMF group were sepsis (n ⫽ 1), bacterial pneumonia (n ⫽ 1), fungal infection (n ⫽ 1),

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FIGURE 4 Episodes of acute rejection per 100 patient days.

FIGURE 2 The rate of freedom from acute rejection for the two treatment groups.

severe acute rejection (n ⫽ 1), and obliterative bronchiolitis (n ⫽ 1).

Acute and Chronic Rejection Freedom from acute rejection at 6 months and 1 year post-transplantation was slightly higher in the Tac/MMF group (57.7% and 50% in the Tac/MMF group vs 45.8% and 33.3% in the CsA/MMF group; p ⫽ n.s.; Figure 2). Comparison of freedom from second (recurrent) rejection showed no difference (96.2% and 84.6% in the Tac/MPA group vs 87.5% and 83.3% in the CsA/MPA group; p ⫽ n.s.; Figure 3). The occurrence of acute rejection episodes per

100 patient days was significantly higher in the cyclosporine group compared with the tacrolimus group (0.426 ⫾ 0.540 AR/100 patient days vs 0.225 ⫾ 0.307 AR/100 patient days; p ⬍ .05; Figure 4). A total of 4 patients from the CsA/MMF group required a switch to Tac/MMF to control ongoing rejection, whereas no patient in the Tac group required a switch to CsA. Switch was successful in 3 patients, whereas 1 patient showed a slower, but ongoing, progression of obliterative bronchiolitis (bronchiolitis obliterans syndrome [BOS] stage III) and died 8 months after the switch. Two patients in each group developed BOS during the follow-up (Tac/MMF: first patient, BOS I 90 days post-transplant; second patient, BOS I 400 days post-transplant with progression to BOS III during the follow-up period; CsA/MMF: first patient, BOS I at day 120 with progression to BOS III as mentioned earlier; second patient, BOS I 450 days post-transplant with progression to BOS III during the follow-up period). Two patients from the CsA group had to be re-transplanted on day 22 and day 50, respectively, due to early unspecific graft failure and ongoing rejection. One re-transplantation was successful, but the latter patient died from pneumonia 6 weeks after the operation.

Infections

FIGURE 3 The rate of freedom from the second (recurrent) acute rejection for the two treatment groups.

Incidence and causes of infections are shown in Table II. There was no difference in the incidence of bacterial and viral infections in either group, but there was a trend toward more fungal infections in the Tac/MPA group (n ⫽ 7 vs n ⫽ 1, p ⫽ n.s.)—also accounting for 2 late deaths in this group compared with 1 late death for this reason in the CsA/MMF

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TABLE II Incidence and causes of infections Episodes/100 patient days Total Bacterial Viral Fungal

Cyclosporine ⴙ mycophenolate mofetil

Tacrolimus ⴙ mycophenolate mofetil

0.41 0.28 0.10 0.03

0.47 0.26 0.13 0.08

group. The incidence of fungal infections per 100 patient days was also slightly higher in the Tac/MMF group compared with the CsA/MMF group, although the difference was not statistically significant (0.08 vs 0.03, p ⫽ n.s.).

Side Effects At 1 year post-transplantation, mean creatinine levels were comparable between the groups (1.22 mg/dl in the Tac/MMF group vs 1.31 mg/dl in the CsA/MMF group, p ⫽ n.s.), and there was no apparent incidence of renal dysfunction in the patient cohort as defined by a serum creatinine level ⬎2.0 mg/dl. None of the patients required hemofiltration or hemodialysis after post-operative day 30 in the follow-up period. At 1 year after transplantation, 30% of the patients in the CsA/MMF group and 12% in the Tac/MMF group developed arterial hypertension and required anti-hypertensive therapy on a regular basis. Fifty percent of the patients in the CsA/MMF group compared with 27% in the Tac/MMF group required statin therapy, presenting with cholesterol levels ⱖ300 mg/dl. New-onset diabetes mellitus, defined as a need for anti-diabetic medication for a period of ⬎3 months, was observed in the Tac group only (3 patients ⫽ 11.5%).

DISCUSSION As previously reported, MMF seems to have an additional immunosuppressive efficacy when combined with tacrolimus or cyclosporine. Compared with azathioprine it has been reported to reduce significantly the rate of acute rejection in kidney transplantation,9,10 heart transplantation,11,12 and lung transplantation.6,21 In comparison to historic reports of Tac or CsA combined with azathioprine the incidence of acute rejection episodes in the early post-operative period has been reported to be favorably reduced for both drugs when combined with MMF.4,5 A recent randomized trial in heart trans-

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plant patients showed that routine monitoring of mycophenolate acid (MPA) levels, the active metabolite of MMF, led to optimized patient management, minimized acute rejection episodes, and thus to improved efficacy of the immunosuppressive therapy.19 Measurements of MPA levels were routinely undertaken in our study and doses were adjusted in the presence of clinical side effects. Patients who undergo refractory acute rejection are known to be at higher risk for the development of obliterative bronchiolitis as a manifestation of chronic rejection.13 A reduced incidence of acute rejection episodes and refractory rejection might result in a reduced incidence of OB. In our trial, 92% of the patients in both groups were free from OB 1 year after transplantation. Further follow-up is required to determine the longer term effect of both immunosuppressive regimens on the development of OB. The results of this study demonstrate the Tac/ MMF regimen to be more efficacious compared with CsA/MMF treatment. The rate of freedom from acute rejection was slightly higher in the Tac/MMF group at 6 months and at 1 year after transplantation; that is, we found a significantly lower incidence of acute rejection per 100 patient days in the Tac/MMF group than in the CsA/MMF group. Earlier studies in liver transplantation reported similar results showing that tacrolimus was associated with fewer rejection episodes and prolonged graft survival when compared with CsA.20 Consistent with other studies14,15 tacrolimus proved to be an effective rescue agent in lung transplantation. Three of 4 patients in the CsA/ MMF group who required a switch to Tac because of ongoing rejection were successfully converted and, additionally, no episodes of refractory acute rejection were observed in the Tac group. The relatively higher immunosuppressive potential of tacrolimus did not lead to a significantly increased number of infections. Therefore, our patients did not seem to be over-immunosuppressed. The incidence of bacterial and viral infections was similar in both groups, but a trend toward more fungal infections in the Tac/MMF group was observed (n ⫽ 7 vs n ⫽ 1, p ⫽ n.s.). This is consistent with the results of an earlier study published by the University of Pittsburgh that reported a significantly higher risk for fungal infections in tacrolimustreated patients after lung transplantation when compared with cyclosporine.4 Although we found no significant signs of overimmunosuppression, caution should be paid to the

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elevated incidence and severity of fungal infections in the Tac/MMF group, which accounted for 2 late deaths. Therefore, frequent screening for fungal infections (especially Aspergillus) is strongly recommended, especially in Tac-treated patients, so that antifungal treatment can be initiated if required. During 1 year of follow-up none of the patients developed renal insufficiency (defined as a serum creatinine level ⬎2.0 mg/dl). Mean creatinine levels at 1 year after transplantation were similar in both groups and only slightly elevated. Patients in the cyclosporine group had a greater need for antihypertensive agents and statins, which is a common finding with administration of cyclosporine.22–24 Another difference between the two treatments was the development of diabetes mellitus after transplantation. Three patients in the Tac/MMF group developed new-onset diabetes mellitus compared with none in the CsA/MMF group. Tacrolimus and cyclosporine are both known to increase the risk for diabetes mellitus, and steroids have an additional effect.16 Earlier kidney and liver transplantation studies reported a higher risk for patients receiving tacrolimus compared with cyclosporine,17,18 which was also demonstrated in our patients. Our experience with Tac in combination with azathioprine in lung transplantation showed that the effect was often reversible by reducing the Tac dosage. Whether this is also true for the combination with MMF needs to be confirmed. In conclusion, the addition of MMF to tacrolimus or cyclosporine results in a more efficacious immunosuppressive regimen. With regard to the prevention and treatment of acute rejection tacrolimus seems to be more potent than cyclosporine. The effectiveness of tacrolimus as a rescue agent is not paralleled with undue signs of over-immunosuppression. However, caution should be paid to the incidence and severity of fungal infections in the tacrolimus group. Effects on the development of obliterative bronchiolitis need to be confirmed with longer term follow-up. REFERENCES 1. Hosenpud JD. The Registry of the International Society of Heart and Lung Transplantation: sixteenth official report— 1999. J Heart Lung Transplant 1999;18(7):611–26. 2. Griffith BP, Hardesty RL, Armitage JM, et al. Acute rejection of lung allograft with various immunosuppressive protocols. Ann Thorac Surg 1992;54:846. 3. Griffith BP, Bando K, Hardesty R, et al. A prospective randomized trial of FK506 versus cyclosporine after human pulmonary transplantation. Transplantation 1994;57:848 –51.

The Journal of Heart and Lung Transplantation May 2001 4. Keenan RJ, Konishi H, Kawai A, et al. Clinical trial of tacrolimus versus cyclosporin in lung transplantation. Ann Thorac Surg 1995;60:580 –5. 5. Keenan RJ, Dauber JH, Iacono AT, et al. Long term follow up clinical trial of tacrolimus versus cyclosporin for lung transplantation. J Heart Lung Transplant 1998:17(1):58. 6. Reichenspurner H, Kur F, Treede H, et al. Optimization of an immunosuppressive protocol after lung transplantation. Transplantation 1999;68:67–71. ¨ berfuhr P, Martin S, et al. Single-center 7. Meiser BM, U randomized trial comparing tacrolimus (FK506) and cyclosporin in the prevention of acute myocardial rejection. J Heart Lung Transplant 1998;17(8):782– 8. 8. Reichenspurner H, Ertel W, Hammer C, et al. Immunologic monitoring of heart transplant patients under cyclosporin immunosuppression. Transplant Proc 1984;16:1251– 4. 9. European Mycophenolate Mofetil Cooperative Study Group. Placebo controlled study of mycophonolate mofetil combined with cyclosporin and corticosteroids for prevention of acute rejection. Lancet 1995;345:1321. 10. Vanrenterghem Y, Squifflet JP, Forsythe J, et al. Co-administration of tacrolimus and mycophenolate mofetil in cadaveric renal transplant recipients. Transplant Proc 1998;30(4): 1290 –1. 11. Costanzo MR, on behalf of the Mycophenolate Mofetil Cooperative Study Investigators. Results of the randomized trial of mycophenolate mofetil vs azathioprine in heart transplantation. Proceedings from the 16th annual meeting of the American Society of Transplant Physicians. Abstract 9. 1997:87. 12. Meiser BM, Pfeiffer M, Schmidt D, et al. Combination therapy with tacrolimus and mycophenolate mofetil following cardiac transplantation: importance of mycophenolic acid therapeutic drug monitoring. J Heart Lung Transplant 1999; 18(2):143–9. 13. Bando K, Paradis IL, Komatsu K, et al. Analysis of time dependent risks for infection, rejection and death after pulmonary transplantation. J Thorac Cardiovasc Surg 1995; 109:49 –59. 14. Knoop C, Antoine M, Vachie´ry JL, et al. FK506 rescue therapy for irreversible airway rejection in heart–lung transplant recipients: report of five cases. Transplant Proc 1994; 26:3240 –1. 15. Kesten S, Chaparro C, Scavuzzo M, et al. Tacrolimus as rescue therapy for bronchiolitis obliterans syndrome. J Heart Lung Transplant 1997;16:905–912. 16. Jindal RM. Post-transplant diabetes mellitus—a review. Transplantation 1994;58:1289 –98. 17. Golling M, Lehmann T, Senninger N, et al. Tacrolimus reduction improves glucose metabolism and insulin secretion following liver transplantation. Presented at second international conference on New Trends in Clinical and Experimental Immunosuppression, Geneva, Switzerland. Abstract. 1996:68. 18. Mu ¨hlbacher F. 12-month results of the European tacrolimus kidney study. Adv Immunosuppression 1996;4(3):2. 19. Meiser BM, Pfeiffer M, Schmidt D, et al. Combination therapy with macrolimus and mycophenolate mofetil following cardiac transplantation: importance of mycophenolic acid therapeutic drug monitoring. J Heart Lung Transplant 1999; 18(2):143–9. 20. Hadley S, Samore MH, Lewis WD, et al. Major infectious

The Journal of Heart and Lung Transplantation Volume 20, Number 5 complications after orthotopic liver transplantation and comparison of outcomes in patients receiving cyclosporine or FK506 as primary immunosuppression. Transplantation 1995;59(6):851–9. 21. Ross DJ, Waters PF, Levine M, et al. Mycophenolate mofetil versus azathioprine immunosuppressive regimens after lung transplantation: preliminary experience. J Heart Lung Transplant 1998;17(8):768 –74. 22. Thiel G, Bock A, Spondlin M, et al. Long term benefits and

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risks of cyclosporin A (Sandimmun)—an analysis at 10 years. Transplant Proc 1994;26(5):2493– 8. 23. Atger V, Cambillau M, Guillemain R, et al. Serum lipid abnormalities in heart transplant recipients: predominance of HDL2-like particles in the HDL pattern. Artherosclerosis 1990;81(2):103–10. 24. Spencer CM, Goa KL, Gillis JC. Tacrolimus. An update of ist pharmacology and clinical efficacy in the management of organ transplantation. Drugs 1997;54(6):925–75.