Blood Cells, Molecules and Diseases 53 (2014) 157–160
Contents lists available at ScienceDirect
Blood Cells, Molecules and Diseases journal homepage: www.elsevier.com/locate/bcmd
Pilot study using tacrolimus rather than cyclosporine plus antithymocyte globulin as an immunosuppressive therapy regimen option for severe aplastic anemia in adults Xianmin Zhu, Jun Guan, Jinhuan Xu, Jia Wei, Lijun Jiang, Jin Yin, Lei Zhao, Yicheng Zhang ⁎ Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
a r t i c l e
i n f o
Article history: Submitted 3 August 2013 Revised 8 August 2013 Accepted 21 January 2014 Available online 13 June 2014 (Communicated by R. I. Handin, M.D., 21 January 2014) Keywords: Adults Severe aplastic anemia Immunosuppressive therapy Tacrolimus Antithymocyte globulin
a b s t r a c t Severe aplastic anemia (SAA), which is considered to be an immune-mediated destruction of bone marrow stem cells with pancytopenia and hypoplasia, can be successfully treated with immunosuppressive therapy or hematopoietic stem cell transplantation (HSCT). Between January 2009 and December 2012, thirteen patients diagnosed with SAA were treated with tacrolimus plus rabbit antithymocyte globulin (ATG)-based immunosuppressive therapy (IST). The outcomes were then compared with our previous data for twenty-four patients administered with cyclosporine (CsA) plus rabbit ATG-based IST. All 37 cases accepted methylpredenisolone and recombinant human granulocyte colony-stimulating factor (rhG-CSF) from the first day that rabbit ATG was initiated. A total of 7 (54%) of the 13 patients in the tacrolimus group and 10 (42%) of the 24 cases in the ATG + CsA group achieved the criteria for complete response (CR); the partial response (PR) rate was 31% in the tacrolimus group and 33% in the ATG + CsA group. The median follow-up duration of the tacrolimus group and ATG + CsA group patients was 28 months and 27 months, respectively. Two patients in the tacrolimus group who were red blood cell- and platelet transfusion-dependent died, one of sepsis and the other of cerebral hemorrhage, whereas one patient died from serious infection on the 5th day after ATG was initiated in the ATG + CsA group. No clonal transformation to paroxysmal nocturnal hemoglobinuria (PNH) was observed in either group. Our data provide a possibility of using tacrolimus as part of an IST regimen for SAA in adults who have no opportunity of HSCT from human leukocyte antigen (HLA)-matched sibling donors. © 2014 Elsevier Inc. All rights reserved.
Introduction Severe aplastic anemia (SAA) is a life-threatening bone marrow failure disorder characterized by bone marrow aplasia and peripheral blood pancytopenia [1]. In most cases, the bone marrow failure is attributed to the autoimmune destruction of hematopoietic stem cells [2]. Patients diagnosed with SAA often die of infection, bleeding, or complications from severe anemia [3]. Immunosuppressive therapy (IST) and hematopoietic stem cell transplantation (HSCT) are currently the two major treatments for patients diagnosed with SAA [4,5]. In general, the outcomes of HSCT for SAA are better in children than in adults, accompanied with a better overall survival and fewer chances of graftversus-host disease [6,7]. However, most patients diagnosed with SAA lack an HLA-histocompatible sibling; thus, IST is regarded as a primary consideration for the treatment of SAA. Antithymocyte globulin (ATG) plus cyclosporine (CsA) are administered as the standard IST [8]. ⁎ Corresponding author at: Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jie-Fang Avenue, Wuhan 430030, China. E-mail address: [email protected] (Y. Zhang).
http://dx.doi.org/10.1016/j.bcmd.2014.04.008 1079-9796/© 2014 Elsevier Inc. All rights reserved.
As the most widely used IST for patients diagnosed with SAA, CsA has some troublesome effects that can lead to reduced therapy compliance, including hirsutism and gingival hyperplasia, along with such potential toxicity as nephrotoxicity and neurotoxicity, hypertension, electrolyte disturbance, and dyslipidemia [9]. Tacrolimus, a widely used calcineurin inhibitor, can be substituted for CsA in some cases, such as Acute Severe Colitis (ASC) [10], HSCT [11,12], and solid organ transplantation [13–15]. Additionally, Tacrolimus has a better bioavailability than cyclosporine and thus may be used for oral treatment, and its toxicity profile is appealing. However, fewer studies have been reported to support its use in adult SAA [10]. Here, we first describe the use of tacrolimus substituted for CsA as a uniform IST regimen in combination with ATG for the treatment of 13 adults diagnosed with SAA. Materials and methods Sample A total of 13 newly diagnosed patients with SAA in our department from January 2009 to December 2012 were reviewed. The inclusion
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criteria were as follows: 1) patients of different ages were included who had not received immunosuppressive therapy protocols, such as CSA; 2) patients without past history of basic diseases of the heart, liver, kidney, and lung; 3) patients with active infections were excluded or completely controlled before the regular treatment was initiated; 4) HIV patients and pregnant and lactating women were excluded. The patients were confirmed as SAA according to the following criteria: 1) severe clinical manifestations and signs; 2) meeting at least twothirds of the following hemogram-reticulocyte count ≤ 15,000/μl, absolute neutrophil count (ANC) ≤ 500/μl, and platelet count ≤ 20,000/μl; 3) seriously low hyperplasia bone marrow. Written informed consent was obtained from all patients, and the collection of clinical data was in accordance with the Declaration of Helsinki.
platelet transfusions. No response (NR) was defined as still transfusion dependent or satisfying the criteria for SAA. Death was classified according to the longest follow-up period. The incidence of paroxysmal nocturnal hemoglobinuria (PNH) clones was examined by the flow cytometric analysis of CD55- and CD59-expressing neutrophils or red blood cells. Statistical analysis The median values and frequencies for the categorical data were described by descriptive analyses. Estimates of the survival functions were calculated using the method of Kaplan and Meier. The analyses were performed using SPSS version 17.0 for Windows (SPSS, Inc., Chicago, IL).
Treatment regimen Results All 13 patients received a new IST regimen: tacrolimus combined with ATG was substituted for CsA plus ATG. Tacrolimus was used at a concentration of 0.1 mg/kg, with the final plasma concentration maintained at 8–12 ng/mL for at least one year. All patients gradually stopped the treatment with tacrolimus in the third year when their conditions were improving. However, one patient refused to stop the therapy with tacrolimus, even though his condition was well controlled; no obvious side effects were observed or influenced his quality of life during the follow-up observation. A skin test for rabbit ATG was performed to assess allergic hypersensitivity. Rabbit ATG was administered at a dosage of 3.5 mg/kg/day, with a duration of 5 days. Methylprednisolone was started on the first day and ATG was initiated and maintained at a dose of 1 mg/kg/day for 14 days to prevent serum sickness and then tapered down over the subsequent 7 days. Treatment with recombinant human granulocyte colony-stimulating factor (rhG-CSF) was considered as a supportive therapy at a dose of 5 mg/kg/day for a short course until the ANC achieved 500/μl. The concrete dosage and administration are shown in Table 1. Component blood transfusion was performed according to the personal characteristics, as follows: red blood cells (RBCs) were transfused when Hb ≤ 50 g/L and platelet transfusions were performed at a count ≤ 10 × 109/L with the presentation of bleeding or fever. Preventive administration against fungal infections was conducted when ANC ≤ 0.3 × 109/L and treatments against common infections with antibiotic drugs were necessary with fever. Effect evaluations The endpoint was defined according to the responses exhibited after 12 weeks of tacrolimus treatment. The following criteria should be fulfilled for a complete response (CR), ANC N 1.5 × 109/L, hemoglobin N 100 g/L, and platelet counts N 100 × 109/L. A partial response (PR) was considered when the hemogram no longer satisfied the criteria for SAA but was still insufficient to meet the criteria for CR. The concrete criteria were defined as follows: the ANC count increased to more than 0.5 × 109/L, the hemoglobin level increased to more than 80 g/L, and the platelet count was greater than 20 × 109/L or independent of Table 1 Summary of tacrolimus plus ATG based-IST regimen.
Tacrolimus ATG Methylpredenisolone G-CSF
Dose
Route
Frequency
Duration
0.1 mg/kg 3.5 mg/kg 1 mg/kg 5 mg/kg
IV/PO IV IV IM
BID Qday Qday Qday
Days 1– N 365a Days 1–5 Days 1–14 Day 1 until ANC N 500
IST: immunosuppressive therapy; ATG: antithymocyte globulin; IV: intravenously; PO: by mouth; BID: twice-daily; Qday: once-daily; G-CSF: granulocyte colony-stimulating factor; IM: intramuscular injection; ANC: absolute neutrophil count. a The final plasma concentration of tacrolimus should be maintained at 8–12 ng/mL for one year at least.
Thirteen patients with SAA diagnosed between 2009 and 2012 who had no opportunity for HSCT underwent tacrolimus-based IST. All of these patients were compared to a previous study on ATG + CsAbased IST at our institution between 2004 and 2011, a study of 24 SAA patients who all accepted a standard treatment of combined ATG and CsA [16]. The median age of the confirmed patients in the tacrolimus group was 26, and the median observation time of these cases was 844 days (range: 108 to 1335 days). Of the 13 cases, 7 (54%) patients in the tacrolimus group achieved the criteria for CR compared to 10 (42%) of the 24 cases in the ATG + CsA group, a group for which the median follow-up was 27 months. Basic information, the follow-up observation time, responses, and efficacy outcomes are shown in Table 2 for the tacrolimus group. The median follow-up among the cases of CR in the tacrolimus group was approximately 975 days. Compared to 8 (33%) patients achieving the criteria for PR in the ATG + CsA group, 4 (31%) patients met the criteria for PR in the tacrolimus group. The total effective rate of tacrolimus treatment in 13 patients was 85% (Fig. 1). During follow-up, two patients in the tacrolimus group died, one of sepsis and one of cerebral hemorrhage, 108 days and 806 days later, respectively, and both were red blood cell and platelet transfusion dependent. In addition, one patient died from serious infection on the 5th day after the initiation of ATG therapy in the ATG + CsA group. One patient showed a slightly transient hyperkalemia and recovered when the dosage of tacrolimus was adjusted. Gingival hyperplasia was observed in an additional patient during the long-term maintenance therapy with tacrolimus. In our previous ATG + CsA group, prior to the ATG + CsA-based IST, 18 (75%) cases of fever were reported, including 10 with definite infection foci, and broad-spectrum antibiotics were immediately initiated in all 18 cases. A total of 18 patients were diagnosed with fungal infection, including one patient with combined pulmonary tuberculosis after IST. The patients gradually achieved remission after standardized anti-infective therapy was administered. In addition, perianal abscess still occurred in 2 patients with ATG + CsA therapy, even though all strictly continued with 1:5000 potassium permanganate sitz bath. Data on other common complications, such as hirsutism and serum creatinine, were not recorded in the present study. Neither group showed relapse nor clonal transformation. Due to the small sample size, a meaningful statistical analysis was not performed on these data. Discussion As a standard initial IST for SAA in adults, horse ATG and CsA results in hematologic recovery in 60% to 70% of patients and has shown excellent long-term survival responses in a few large prospective studies in the United Stated, Europe, and Japan [5,17–21]. These findings compare favorably with the total effective rate of 75% based on our initial reported experience with CsA-based IST in adult SAA [16]. The present study
X. Zhu et al. / Blood Cells, Molecules and Diseases 53 (2014) 157–160
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Table 2 Basic information, follow-up observation time and outcomes of adults with SAA treated by tacrolimus-based IST.
1 2 3 4 5 6 7 8 9 10 11 12 13
Gender
Age
Diagnosis
ANC (/uL)
Plt (/uL)
Hb (g/dl)
Follow-up time (day)
Response
Transfusion
Male Female Female Female Male Male Male Male Female Male Male Female Female
23 17 25 15 53 26 22 44 32 19 48 42 36
SAA SAA SAA SAA SAA SAA SAA SAA SAA SAA SAA SAA SAA
300 250 462 377 130 420 510 200 120 106 570 350 170
11,000 6000 15,000 18,000 9000 7000 12,000 8000 15,000 7000 18,000 11,000 18,000
62 65 83 71 55 68 79 58 72 47 77 88 49
1335+ 1292+ 1266+ 108 1194+ 1086+ 975+ 844+ 806 589+ 323+ 305+ 208+
CR CR CR Death PR PR CR CR Death CR PR CR PR
– – – RBC, Pt RBC – – – RBC, Pt – – – –
RBC: red blood cell; Pt: platelet; CR: complete response; PR: partial response.
of 37 SAA patients treated with IST showed CR and PR rates of greater than 75%, with a robust function with regard to both tacrolimus- and CsA-based therapies. Compared to the previously reported clonal transformation rates of approximately 10% for CsA-based IST [20,22–25], no clonal transformation to PNH or MDS/AML was observed in either of our groups. A recent study on pediatric SAA reported that tacrolimus could be used as an alternative to cyclosporine in the maintenance phase of IST, with 88% PR; in this eight-case study, one case failed to response to IST-based therapy and subsequently underwent successful unrelated cord blood HSCT, and one patient showed PNH transformation, as detected using flow cytometry [28]. In contrast to CsA, tacrolimus was well tolerated and demonstrated a weak link to hirsutism and gingival hyperplasia [26], with a better bioavailability for oral treatment [10]. In comparison to the side effects observed in the above-mentioned tacrolimus group in pediatric SAA, including hypertension, anemia, and alopecia, there were no apparent complications in our cases, except for one case of slight hyperkalemia, which recovered to normal when the dosage was reduced by half, and another with a complication manifested as gingival hyperplasia. However, nearly all of the cases of pediatric SAA treated with CsA showed hirsutism and gingival hyperplasia, along with more common infectious diseases [26]. Tacrolimus proved to be 10–100 times more effective than cyclosporine with regard to immunosuppressive actions. However, tacrolimus always involves some well-established effects, such as nephrotoxic, diabetogenic, neurological, and cardiovascular effects, and has often been associated with several common side effects, including tremor, headache, diarrhea, hypertension, nausea, and renal dysfunction in addition to hyperkalemia, hypomagnesemia, hypophosphatemia, and diabetes mellitus [9,27]. Regardless, with decreased rates of infection and malignancy, tacrolimus has exhibited much more safety and less impact on renal function and blood pressure than cyclosporine [28].
Although no case relapsed in the two groups, obvious limitations were observed, thereby influencing the evaluation of long-term outcomes. The first one limitation was the relatively short follow-up periods, with a median follow-up period of 28 months and 27 months, respectively, in the tacrolimus group and ATG + CsA group. A second limitation was the relatively small sample size, particularly in the tacrolimus group. Third, and most importantly, was the lack of a concurrently randomized control group, as our study utilized a historical control. The well-known disadvantages related to the use of a historical control, such as selection bias and time bias, were considered, and great efforts were made to reduce the potential bias included in this work. In the previous ATG + CsA group, the patients were selected according to enrollment criteria aimed at a domestic population, and identical criteria for the tacrolimus group were used to limit the selection bias. However, subtle differences actually existed in the effect evaluations between the two groups: an absolutely normal hemogram needed to be maintained after ATG treatment and last a period of 12 months in the ATG + CsA group, whereas the endpoint of CR achieved in the tacrolimus group was 12 weeks after therapy. Additionally, we designed more strict guidelines to rule out infection before the subjects received tacrolimus. Other criteria were identical, as mentioned above. Because there was no obvious improvement in the survival time, any potential time bias was diminished. Although limitations existed in our research, it is undeniable that tacrolimus, which is extensively used as IST in HSCT and solid organ transplantation, can be applied in adult SAA as an applicable alternative to CsA and an effective complement to an IST regimen when a human leukocyte antigen (HLA)-matched sibling donor is unavailable. In general, further investigation should be conducted in such groups to reveal the relationship between the safety and efficacy of tacrolimus used as IST in adults with SAA by expanding the sample size and extending the duration of follow-up. Conclusion This pilot study reveals the possibility that tacrolimus plus antithymocyte globulin may offer high efficiency in the treatment of patients with SAA, with a concomitant decrease in side effects. Thus, tacrolimus may be considered as an alternative to cyclosporine as part of an IST regimen for patients with SAA when HLA-matched sibling donors are not available. Author contributions
Fig. 1. Kaplan–Meier estimates of relapse-free survival among patients with SAA treated with tacrolimus plus antithymocyte globulin.
X.Z. and Y.Z. were the primary designers and take principal responsibility for this manuscript. X.Z. and J.G. collected and analyzed the data. X.Z. wrote the paper. J.G. assisted in the statistical analysis. J.W., J.X., and
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L.J. analyzed the data and improved the paper. The remaining authors were responsible for the patients' clinical management. Acknowledgments This study was supported by grant nos. 30971293 and 30670897 from the National Natural Science Foundation of China. We are grateful for the previous profiles in SAA provided by Huang Lifang, Ph.D. We also thank the patients and the family members for their consent to participate in this work. References [1] Norbert Frickhofen, Hermann Heimpel, P. Joachim, Kaltwasser, Hubert Schrezenmeier, Antithymocyte globulin with or without cyclosporin A: 11-year follow-up or a randomized trial comparing treatments of aplastic anemia, Blood 101 (2003) 1236–1242. [2] Robert A. Brodsky, Allen R. Chen, Donna Dorr, Ephraim J. Fuchs, Carol Ann Huff, Leo Luznik, et al., High-dose cyclophosphamide for severe aplastic anemia: long-term follow-up, Blood 115 (2010) 2136–2141. [3] André Tichelli, Hubert Schrezenmeier, Gérard Socié, Judith Marsh, Andrea Bacigalupo, Ulrich Dührsen, et al., A randomized controlled study in patients with newly diagnosed severe aplastic anemia receiving antithymocyte globulin (ATG), cyclosporine, with or without G-CSF: a study of the SAA Working Party of the European Group for Blood and Marrow Transplantation, Blood 117 (2011) 4434–4441. [4] R.A. Brodsky, R.J. Jones, Aplastic anaemia, Lancet 365 (2005) 1647–1656. [5] N.S. Young, R.T. Calado, P. Scheinberg, Current concepts in the pathophysiology and treatment of aplastic anemia, Blood 108 (2006) 2509–2519. [6] M.M. Horowitz, Current status of allogeneic bone marrow transplantation in acquired aplastic anemia, Semin. Hematol. 37 (2000) 30–42. [7] L. Ades, J.Y. Mary, M. Robin, C. Ferry, R. Porcher, Hélène Esperou, et al., Long-term outcome after bone marrow transplantation for severe aplastic anemia, Blood 103 (2004) 2490–2497. [8] N. Frickhofen, S.J. Rosenfeld, Immunosuppressive treatment of aplastic anemia with antithymocyte globuilin and cyclosporine, Semin. Hematol. 37 (2000) 56–68. [9] L.J. Scott, K. McKeage, S.J. Keam, G.L. Plosker, Tacrolimus: a further update of its use in the management of organ transplantation, Drugs 63 (2003) 1247–1297. [10] Bosmat Dayan, Dan Turner, Role of surgery in severe ulcerative colitis in the era of medical rescue therapy, World J. Gastroenterol. 18 (2012) 3833–3838. [11] V. Ratanatharathorn, R.A. Nash, D. Przepiorka, S.M. Devine, J.L. Klein, D. Weisdorf, et al., Phase III study comparing methotrexate and tacrolimus (prograf, FK506) with methotrexate and cyclosporine for graft-versus-host disease prophylaxis after HLA-identical sibling bone marrow transplantation, Blood 92 (1998) 2303–2314. [12] R.A. Nash, J.H. Antin, C. Karanes, J.W. Fay, B.R. Avalos, A.M. Yeager, et al., Phase 3 study comparing methotrexate and tacrolimus with methotrexate and cyclosporine for prophylaxis of acute graft-versus-host disease after marrow transplantation from unrelated donors, Blood 96 (2000) 2062–2068. [13] E.M. Haddad, V.C. McAlister, E. Renouf, R. Malthaner, M.S. Kjaer, L.L. Gluud, et al., Cyclosporin versus tacrolimus for liver transplanted patients, Cochrane Database Syst. Rev. 4 (2006) CD005161 (Online).
[14] R. Trompeter, G. Filler, N.J. Webb, A.R. Watson, D.V. Milford, G. Tyden, et al., Randomized trial of tacrolimus versus cyclosporine microemulsion in renal transplantation, Pediatr. Nephrol. 17 (2002) 141–149. [15] D.O. Taylor, M.L. Barr, B. Radovancevic, D.G. Renlund, R.M. Mentzer Jr., F.W. Smart, et al., A randomized, multicenter comparison of tacrolimus and cyclosporine immunosuppressive regimens in cardiac transplantation: decreased hyperlipidemia and hypertension with tacrolimus, J. Heart Lung Transplant. 18 (1999) 336–345. [16] Huang Lifang, Luo Lin, Sun Hanying, et al., Analysis of the therapeutic effect of ATG combined with cyclosporine in 24 cases with severe aplastic anemia, J. Intern. Intensive Med. 17 (2011) 348–350. [17] N. Frickhofen, J.P. Kaltwasser, H. Schrezenmeier, A. Raghavachar, H.G. Vogt, F. Herrmann, et al., Treatment of aplastic anemia with antilymphocyte globulin and melthylprednisolone with or without cyclosporine: the German Aplastic Anemia Study Group, N. Engl. J. Med. 324 (1991) 1297–1304. [18] S.J. Rosenfeld, J. Kimball, D. Vining, N.S. Young, Intensive immunosuppression with antithymocyte globulin and cyclosporine as treatment for severe acquired aplastic anemia, Blood 85 (1995) 3058–3065. [19] M. Fuhrer, S. Burdach, W. Ebell, H. Gadner, R. Haas, J. Harbott, et al., Relapse and clonal disease in children with aplastic anemia (AA) after immunosuppressive therapy (IST): the SAA 94 experience. German/Austrian Pediatric Aplastic Anemia Working Group, Klin. Padiatr. 210 (1998) 173–179. [20] S. Kojima, S. Hibi, Y. Kosaka, Immunosuppressive therapy using antithymocyte globulin, cyclosporine, and danazol with or without human granulocyte colony-stimulating factor in children with acquired aplastic anemia, Blood 96 (2009) 2049–2054. [21] A. Bacigalupo, B. Bruno, P. Saracco, E.Di. Bona, A. Locasciulli, F. Locatelli, et al., Antilymphocyte globulin, cyclosporine, prednisolone, and granulocyte colony-stimulating factor for severe aplastic anemia: an update of the GITMO/EBMT study on 100 patients. European Group for Blood and Marrow Transplantation (EBMT) Working Party on Severe Aplastic Anemia and the Gruppo Italiano Trapianti di Midolio Osseo (GITMO), Blood 95 (2009) 1931–1934. [22] P. Scheinberg, C.O. Wu, O. Nunez, et al., Long-term outcome of pediatric patients with severe aplastic anemia treated with antithymocyte globulin and cyclosporine, J. Pediatr. 153 (2008) 814–819. [23] M. Fuhrer, U. Rampf, I. Baumann, A. Faldum, C. Niemeyer, G.J. Schaub, et al., Immunosuppressive therapy for aplastic anemia in children: a more severe disease predicts better survival, Blood 106 (2005) 2102–2104. [24] P. Saracco, P. Quarello, A.P. Iori, M. Zecca, D. Longoni, J. Svahn, et al., Cyclosporin A response and dependence in children with acquired aplastic anemia: a multicentre retrospective study with long-term observation follow-up, Br. J. Haematol. 140 (2008) 197–205. [25] B. Pongtanakul, P.K. Das, K. Charpentier, Y. Dror, Outcome of children with aplastic anemia treated with immunosuppressive therapy, Pediatr. Blood Cancer 50 (2008) 52–57. [26] Abdulrahman Alsultan, Neil A. Goldenberg, Nicole Kaiser, Taru Hays, Tacrolimu as an alternative to cyclosporine in the maintenance phase of immunosuppressive therapy for severe aplastic anemia in children, Pediatr. Blood Cancer 52 (2009) 626–630. [27] Terrence Colin Keaney, Tina Bhutani, Priya Sivanesan, Grace D. Bandow, Sari Beth Weinstein, Lawrence C.C. Cheung, et al., Open-label, pilot study examining sequential therapy with oral tacrolimus and topical tacrolimus for severe atopic dermatitis, J. Am. Acad. Dermatol. 67 (2012) 636–641. [28] I.H. Klein, A. Abrahams, T. Van Ede, R.J. Hene, H.A. Koomans, G. Ligtenberg, et al., Different effects of tacrolimus and cyclosporine on renal hemodynamics and blood pressure in healthy subjects, Transplantation 73 (2002) 732–736.
Contents lists available at ScienceDirect
Blood Cells, Molecules and Diseases journal homepage: www.elsevier.com/locate/bcmd
Pilot study using tacrolimus rather than cyclosporine plus antithymocyte globulin as an immunosuppressive therapy regimen option for severe aplastic anemia in adults Xianmin Zhu, Jun Guan, Jinhuan Xu, Jia Wei, Lijun Jiang, Jin Yin, Lei Zhao, Yicheng Zhang ⁎ Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
a r t i c l e
i n f o
Article history: Submitted 3 August 2013 Revised 8 August 2013 Accepted 21 January 2014 Available online 13 June 2014 (Communicated by R. I. Handin, M.D., 21 January 2014) Keywords: Adults Severe aplastic anemia Immunosuppressive therapy Tacrolimus Antithymocyte globulin
a b s t r a c t Severe aplastic anemia (SAA), which is considered to be an immune-mediated destruction of bone marrow stem cells with pancytopenia and hypoplasia, can be successfully treated with immunosuppressive therapy or hematopoietic stem cell transplantation (HSCT). Between January 2009 and December 2012, thirteen patients diagnosed with SAA were treated with tacrolimus plus rabbit antithymocyte globulin (ATG)-based immunosuppressive therapy (IST). The outcomes were then compared with our previous data for twenty-four patients administered with cyclosporine (CsA) plus rabbit ATG-based IST. All 37 cases accepted methylpredenisolone and recombinant human granulocyte colony-stimulating factor (rhG-CSF) from the first day that rabbit ATG was initiated. A total of 7 (54%) of the 13 patients in the tacrolimus group and 10 (42%) of the 24 cases in the ATG + CsA group achieved the criteria for complete response (CR); the partial response (PR) rate was 31% in the tacrolimus group and 33% in the ATG + CsA group. The median follow-up duration of the tacrolimus group and ATG + CsA group patients was 28 months and 27 months, respectively. Two patients in the tacrolimus group who were red blood cell- and platelet transfusion-dependent died, one of sepsis and the other of cerebral hemorrhage, whereas one patient died from serious infection on the 5th day after ATG was initiated in the ATG + CsA group. No clonal transformation to paroxysmal nocturnal hemoglobinuria (PNH) was observed in either group. Our data provide a possibility of using tacrolimus as part of an IST regimen for SAA in adults who have no opportunity of HSCT from human leukocyte antigen (HLA)-matched sibling donors. © 2014 Elsevier Inc. All rights reserved.
Introduction Severe aplastic anemia (SAA) is a life-threatening bone marrow failure disorder characterized by bone marrow aplasia and peripheral blood pancytopenia [1]. In most cases, the bone marrow failure is attributed to the autoimmune destruction of hematopoietic stem cells [2]. Patients diagnosed with SAA often die of infection, bleeding, or complications from severe anemia [3]. Immunosuppressive therapy (IST) and hematopoietic stem cell transplantation (HSCT) are currently the two major treatments for patients diagnosed with SAA [4,5]. In general, the outcomes of HSCT for SAA are better in children than in adults, accompanied with a better overall survival and fewer chances of graftversus-host disease [6,7]. However, most patients diagnosed with SAA lack an HLA-histocompatible sibling; thus, IST is regarded as a primary consideration for the treatment of SAA. Antithymocyte globulin (ATG) plus cyclosporine (CsA) are administered as the standard IST [8]. ⁎ Corresponding author at: Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jie-Fang Avenue, Wuhan 430030, China. E-mail address: [email protected] (Y. Zhang).
http://dx.doi.org/10.1016/j.bcmd.2014.04.008 1079-9796/© 2014 Elsevier Inc. All rights reserved.
As the most widely used IST for patients diagnosed with SAA, CsA has some troublesome effects that can lead to reduced therapy compliance, including hirsutism and gingival hyperplasia, along with such potential toxicity as nephrotoxicity and neurotoxicity, hypertension, electrolyte disturbance, and dyslipidemia [9]. Tacrolimus, a widely used calcineurin inhibitor, can be substituted for CsA in some cases, such as Acute Severe Colitis (ASC) [10], HSCT [11,12], and solid organ transplantation [13–15]. Additionally, Tacrolimus has a better bioavailability than cyclosporine and thus may be used for oral treatment, and its toxicity profile is appealing. However, fewer studies have been reported to support its use in adult SAA [10]. Here, we first describe the use of tacrolimus substituted for CsA as a uniform IST regimen in combination with ATG for the treatment of 13 adults diagnosed with SAA. Materials and methods Sample A total of 13 newly diagnosed patients with SAA in our department from January 2009 to December 2012 were reviewed. The inclusion
158
X. Zhu et al. / Blood Cells, Molecules and Diseases 53 (2014) 157–160
criteria were as follows: 1) patients of different ages were included who had not received immunosuppressive therapy protocols, such as CSA; 2) patients without past history of basic diseases of the heart, liver, kidney, and lung; 3) patients with active infections were excluded or completely controlled before the regular treatment was initiated; 4) HIV patients and pregnant and lactating women were excluded. The patients were confirmed as SAA according to the following criteria: 1) severe clinical manifestations and signs; 2) meeting at least twothirds of the following hemogram-reticulocyte count ≤ 15,000/μl, absolute neutrophil count (ANC) ≤ 500/μl, and platelet count ≤ 20,000/μl; 3) seriously low hyperplasia bone marrow. Written informed consent was obtained from all patients, and the collection of clinical data was in accordance with the Declaration of Helsinki.
platelet transfusions. No response (NR) was defined as still transfusion dependent or satisfying the criteria for SAA. Death was classified according to the longest follow-up period. The incidence of paroxysmal nocturnal hemoglobinuria (PNH) clones was examined by the flow cytometric analysis of CD55- and CD59-expressing neutrophils or red blood cells. Statistical analysis The median values and frequencies for the categorical data were described by descriptive analyses. Estimates of the survival functions were calculated using the method of Kaplan and Meier. The analyses were performed using SPSS version 17.0 for Windows (SPSS, Inc., Chicago, IL).
Treatment regimen Results All 13 patients received a new IST regimen: tacrolimus combined with ATG was substituted for CsA plus ATG. Tacrolimus was used at a concentration of 0.1 mg/kg, with the final plasma concentration maintained at 8–12 ng/mL for at least one year. All patients gradually stopped the treatment with tacrolimus in the third year when their conditions were improving. However, one patient refused to stop the therapy with tacrolimus, even though his condition was well controlled; no obvious side effects were observed or influenced his quality of life during the follow-up observation. A skin test for rabbit ATG was performed to assess allergic hypersensitivity. Rabbit ATG was administered at a dosage of 3.5 mg/kg/day, with a duration of 5 days. Methylprednisolone was started on the first day and ATG was initiated and maintained at a dose of 1 mg/kg/day for 14 days to prevent serum sickness and then tapered down over the subsequent 7 days. Treatment with recombinant human granulocyte colony-stimulating factor (rhG-CSF) was considered as a supportive therapy at a dose of 5 mg/kg/day for a short course until the ANC achieved 500/μl. The concrete dosage and administration are shown in Table 1. Component blood transfusion was performed according to the personal characteristics, as follows: red blood cells (RBCs) were transfused when Hb ≤ 50 g/L and platelet transfusions were performed at a count ≤ 10 × 109/L with the presentation of bleeding or fever. Preventive administration against fungal infections was conducted when ANC ≤ 0.3 × 109/L and treatments against common infections with antibiotic drugs were necessary with fever. Effect evaluations The endpoint was defined according to the responses exhibited after 12 weeks of tacrolimus treatment. The following criteria should be fulfilled for a complete response (CR), ANC N 1.5 × 109/L, hemoglobin N 100 g/L, and platelet counts N 100 × 109/L. A partial response (PR) was considered when the hemogram no longer satisfied the criteria for SAA but was still insufficient to meet the criteria for CR. The concrete criteria were defined as follows: the ANC count increased to more than 0.5 × 109/L, the hemoglobin level increased to more than 80 g/L, and the platelet count was greater than 20 × 109/L or independent of Table 1 Summary of tacrolimus plus ATG based-IST regimen.
Tacrolimus ATG Methylpredenisolone G-CSF
Dose
Route
Frequency
Duration
0.1 mg/kg 3.5 mg/kg 1 mg/kg 5 mg/kg
IV/PO IV IV IM
BID Qday Qday Qday
Days 1– N 365a Days 1–5 Days 1–14 Day 1 until ANC N 500
IST: immunosuppressive therapy; ATG: antithymocyte globulin; IV: intravenously; PO: by mouth; BID: twice-daily; Qday: once-daily; G-CSF: granulocyte colony-stimulating factor; IM: intramuscular injection; ANC: absolute neutrophil count. a The final plasma concentration of tacrolimus should be maintained at 8–12 ng/mL for one year at least.
Thirteen patients with SAA diagnosed between 2009 and 2012 who had no opportunity for HSCT underwent tacrolimus-based IST. All of these patients were compared to a previous study on ATG + CsAbased IST at our institution between 2004 and 2011, a study of 24 SAA patients who all accepted a standard treatment of combined ATG and CsA [16]. The median age of the confirmed patients in the tacrolimus group was 26, and the median observation time of these cases was 844 days (range: 108 to 1335 days). Of the 13 cases, 7 (54%) patients in the tacrolimus group achieved the criteria for CR compared to 10 (42%) of the 24 cases in the ATG + CsA group, a group for which the median follow-up was 27 months. Basic information, the follow-up observation time, responses, and efficacy outcomes are shown in Table 2 for the tacrolimus group. The median follow-up among the cases of CR in the tacrolimus group was approximately 975 days. Compared to 8 (33%) patients achieving the criteria for PR in the ATG + CsA group, 4 (31%) patients met the criteria for PR in the tacrolimus group. The total effective rate of tacrolimus treatment in 13 patients was 85% (Fig. 1). During follow-up, two patients in the tacrolimus group died, one of sepsis and one of cerebral hemorrhage, 108 days and 806 days later, respectively, and both were red blood cell and platelet transfusion dependent. In addition, one patient died from serious infection on the 5th day after the initiation of ATG therapy in the ATG + CsA group. One patient showed a slightly transient hyperkalemia and recovered when the dosage of tacrolimus was adjusted. Gingival hyperplasia was observed in an additional patient during the long-term maintenance therapy with tacrolimus. In our previous ATG + CsA group, prior to the ATG + CsA-based IST, 18 (75%) cases of fever were reported, including 10 with definite infection foci, and broad-spectrum antibiotics were immediately initiated in all 18 cases. A total of 18 patients were diagnosed with fungal infection, including one patient with combined pulmonary tuberculosis after IST. The patients gradually achieved remission after standardized anti-infective therapy was administered. In addition, perianal abscess still occurred in 2 patients with ATG + CsA therapy, even though all strictly continued with 1:5000 potassium permanganate sitz bath. Data on other common complications, such as hirsutism and serum creatinine, were not recorded in the present study. Neither group showed relapse nor clonal transformation. Due to the small sample size, a meaningful statistical analysis was not performed on these data. Discussion As a standard initial IST for SAA in adults, horse ATG and CsA results in hematologic recovery in 60% to 70% of patients and has shown excellent long-term survival responses in a few large prospective studies in the United Stated, Europe, and Japan [5,17–21]. These findings compare favorably with the total effective rate of 75% based on our initial reported experience with CsA-based IST in adult SAA [16]. The present study
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Table 2 Basic information, follow-up observation time and outcomes of adults with SAA treated by tacrolimus-based IST.
1 2 3 4 5 6 7 8 9 10 11 12 13
Gender
Age
Diagnosis
ANC (/uL)
Plt (/uL)
Hb (g/dl)
Follow-up time (day)
Response
Transfusion
Male Female Female Female Male Male Male Male Female Male Male Female Female
23 17 25 15 53 26 22 44 32 19 48 42 36
SAA SAA SAA SAA SAA SAA SAA SAA SAA SAA SAA SAA SAA
300 250 462 377 130 420 510 200 120 106 570 350 170
11,000 6000 15,000 18,000 9000 7000 12,000 8000 15,000 7000 18,000 11,000 18,000
62 65 83 71 55 68 79 58 72 47 77 88 49
1335+ 1292+ 1266+ 108 1194+ 1086+ 975+ 844+ 806 589+ 323+ 305+ 208+
CR CR CR Death PR PR CR CR Death CR PR CR PR
– – – RBC, Pt RBC – – – RBC, Pt – – – –
RBC: red blood cell; Pt: platelet; CR: complete response; PR: partial response.
of 37 SAA patients treated with IST showed CR and PR rates of greater than 75%, with a robust function with regard to both tacrolimus- and CsA-based therapies. Compared to the previously reported clonal transformation rates of approximately 10% for CsA-based IST [20,22–25], no clonal transformation to PNH or MDS/AML was observed in either of our groups. A recent study on pediatric SAA reported that tacrolimus could be used as an alternative to cyclosporine in the maintenance phase of IST, with 88% PR; in this eight-case study, one case failed to response to IST-based therapy and subsequently underwent successful unrelated cord blood HSCT, and one patient showed PNH transformation, as detected using flow cytometry [28]. In contrast to CsA, tacrolimus was well tolerated and demonstrated a weak link to hirsutism and gingival hyperplasia [26], with a better bioavailability for oral treatment [10]. In comparison to the side effects observed in the above-mentioned tacrolimus group in pediatric SAA, including hypertension, anemia, and alopecia, there were no apparent complications in our cases, except for one case of slight hyperkalemia, which recovered to normal when the dosage was reduced by half, and another with a complication manifested as gingival hyperplasia. However, nearly all of the cases of pediatric SAA treated with CsA showed hirsutism and gingival hyperplasia, along with more common infectious diseases [26]. Tacrolimus proved to be 10–100 times more effective than cyclosporine with regard to immunosuppressive actions. However, tacrolimus always involves some well-established effects, such as nephrotoxic, diabetogenic, neurological, and cardiovascular effects, and has often been associated with several common side effects, including tremor, headache, diarrhea, hypertension, nausea, and renal dysfunction in addition to hyperkalemia, hypomagnesemia, hypophosphatemia, and diabetes mellitus [9,27]. Regardless, with decreased rates of infection and malignancy, tacrolimus has exhibited much more safety and less impact on renal function and blood pressure than cyclosporine [28].
Although no case relapsed in the two groups, obvious limitations were observed, thereby influencing the evaluation of long-term outcomes. The first one limitation was the relatively short follow-up periods, with a median follow-up period of 28 months and 27 months, respectively, in the tacrolimus group and ATG + CsA group. A second limitation was the relatively small sample size, particularly in the tacrolimus group. Third, and most importantly, was the lack of a concurrently randomized control group, as our study utilized a historical control. The well-known disadvantages related to the use of a historical control, such as selection bias and time bias, were considered, and great efforts were made to reduce the potential bias included in this work. In the previous ATG + CsA group, the patients were selected according to enrollment criteria aimed at a domestic population, and identical criteria for the tacrolimus group were used to limit the selection bias. However, subtle differences actually existed in the effect evaluations between the two groups: an absolutely normal hemogram needed to be maintained after ATG treatment and last a period of 12 months in the ATG + CsA group, whereas the endpoint of CR achieved in the tacrolimus group was 12 weeks after therapy. Additionally, we designed more strict guidelines to rule out infection before the subjects received tacrolimus. Other criteria were identical, as mentioned above. Because there was no obvious improvement in the survival time, any potential time bias was diminished. Although limitations existed in our research, it is undeniable that tacrolimus, which is extensively used as IST in HSCT and solid organ transplantation, can be applied in adult SAA as an applicable alternative to CsA and an effective complement to an IST regimen when a human leukocyte antigen (HLA)-matched sibling donor is unavailable. In general, further investigation should be conducted in such groups to reveal the relationship between the safety and efficacy of tacrolimus used as IST in adults with SAA by expanding the sample size and extending the duration of follow-up. Conclusion This pilot study reveals the possibility that tacrolimus plus antithymocyte globulin may offer high efficiency in the treatment of patients with SAA, with a concomitant decrease in side effects. Thus, tacrolimus may be considered as an alternative to cyclosporine as part of an IST regimen for patients with SAA when HLA-matched sibling donors are not available. Author contributions
Fig. 1. Kaplan–Meier estimates of relapse-free survival among patients with SAA treated with tacrolimus plus antithymocyte globulin.
X.Z. and Y.Z. were the primary designers and take principal responsibility for this manuscript. X.Z. and J.G. collected and analyzed the data. X.Z. wrote the paper. J.G. assisted in the statistical analysis. J.W., J.X., and
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L.J. analyzed the data and improved the paper. The remaining authors were responsible for the patients' clinical management. Acknowledgments This study was supported by grant nos. 30971293 and 30670897 from the National Natural Science Foundation of China. We are grateful for the previous profiles in SAA provided by Huang Lifang, Ph.D. We also thank the patients and the family members for their consent to participate in this work. References [1] Norbert Frickhofen, Hermann Heimpel, P. Joachim, Kaltwasser, Hubert Schrezenmeier, Antithymocyte globulin with or without cyclosporin A: 11-year follow-up or a randomized trial comparing treatments of aplastic anemia, Blood 101 (2003) 1236–1242. [2] Robert A. Brodsky, Allen R. Chen, Donna Dorr, Ephraim J. Fuchs, Carol Ann Huff, Leo Luznik, et al., High-dose cyclophosphamide for severe aplastic anemia: long-term follow-up, Blood 115 (2010) 2136–2141. [3] André Tichelli, Hubert Schrezenmeier, Gérard Socié, Judith Marsh, Andrea Bacigalupo, Ulrich Dührsen, et al., A randomized controlled study in patients with newly diagnosed severe aplastic anemia receiving antithymocyte globulin (ATG), cyclosporine, with or without G-CSF: a study of the SAA Working Party of the European Group for Blood and Marrow Transplantation, Blood 117 (2011) 4434–4441. [4] R.A. Brodsky, R.J. Jones, Aplastic anaemia, Lancet 365 (2005) 1647–1656. [5] N.S. Young, R.T. Calado, P. Scheinberg, Current concepts in the pathophysiology and treatment of aplastic anemia, Blood 108 (2006) 2509–2519. [6] M.M. Horowitz, Current status of allogeneic bone marrow transplantation in acquired aplastic anemia, Semin. Hematol. 37 (2000) 30–42. [7] L. Ades, J.Y. Mary, M. Robin, C. Ferry, R. Porcher, Hélène Esperou, et al., Long-term outcome after bone marrow transplantation for severe aplastic anemia, Blood 103 (2004) 2490–2497. [8] N. Frickhofen, S.J. Rosenfeld, Immunosuppressive treatment of aplastic anemia with antithymocyte globuilin and cyclosporine, Semin. Hematol. 37 (2000) 56–68. [9] L.J. Scott, K. McKeage, S.J. Keam, G.L. Plosker, Tacrolimus: a further update of its use in the management of organ transplantation, Drugs 63 (2003) 1247–1297. [10] Bosmat Dayan, Dan Turner, Role of surgery in severe ulcerative colitis in the era of medical rescue therapy, World J. Gastroenterol. 18 (2012) 3833–3838. [11] V. Ratanatharathorn, R.A. Nash, D. Przepiorka, S.M. Devine, J.L. Klein, D. Weisdorf, et al., Phase III study comparing methotrexate and tacrolimus (prograf, FK506) with methotrexate and cyclosporine for graft-versus-host disease prophylaxis after HLA-identical sibling bone marrow transplantation, Blood 92 (1998) 2303–2314. [12] R.A. Nash, J.H. Antin, C. Karanes, J.W. Fay, B.R. Avalos, A.M. Yeager, et al., Phase 3 study comparing methotrexate and tacrolimus with methotrexate and cyclosporine for prophylaxis of acute graft-versus-host disease after marrow transplantation from unrelated donors, Blood 96 (2000) 2062–2068. [13] E.M. Haddad, V.C. McAlister, E. Renouf, R. Malthaner, M.S. Kjaer, L.L. Gluud, et al., Cyclosporin versus tacrolimus for liver transplanted patients, Cochrane Database Syst. Rev. 4 (2006) CD005161 (Online).
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