Moderators: Heather A. Nyman, Pharm.D., BCPS Clinical Pharmacist, Dialysis, University of Utah Dialysis Program, Salt Lake City, Utah

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1 Immunology/Transplantation and Nephrology PRNs Focus Session Long-term Management of the Renal Transplant Recipient Activity No L01-P (Knowledge-Based Activity) Monday, October 17 1:30 p.m. 3:30 p.m. Convention Center: Rooms 319 & 320 Moderators: Heather A. Nyman, Pharm.D., BCPS Clinical Pharmacist, Dialysis, University of Utah Dialysis Program, Salt Lake City, Utah and Angela Q. Maldonado, Pharm.D., BCPS Clinical Assistant Professor of Pharmacotherapy, Washington State University; Kidney Transplant Pharmacist, Providence Hospital, Spokane, Washington Agenda 1:30 p.m. Introduction and Welcome 1:40 p.m. Mineral and Bone Disorder in Chronic Kidney Disease and Kidney Transplantation Timothy M. Clifford, Pharm.D., BCPS Clinical Pharmacist Specialist Transplant/Critical Care; Assistant Adjunct Professor, Pharmacy and Surgery, University of Kentucky, Lexington, Kentucky 2:15 p.m. Anemia Pre- and Post-renal Transplant Shouldn t the Allograft Be the Cure? Joanna Q. Hudson, Pharm.D., FASN, BCPS Associate Professor, The University of Tennessee, Departments of Clinical Pharmacy & Medicine (Nephrology), Memphis, Tennessee 2:50 p.m. The Pharmacokinetics and Pharmacodynamics of Drug Dosing in the Renal Allograft Recipient Ali Olyaei, Pharm.D. Professor of Medicine, Director of Clinical Research, Division of Nephrology and Hypertension, Oregon State University/Oregon Health & Sciences University, Portland, Oregon 3:25 p.m. Closing Remarks Faculty Conflict of Interest Disclosures Timothy M. Clifford: no conflicts to disclose. Joanna Q. Hudson: speaker s bureau for Amgen. Ali Olyaei: no conflicts to disclose. Annual Meeting Long-term Management of the Renal Transplant Recipient 1

2 Learning Objectives 1. Discuss the pathophysiology of mineral and bone disorder (MBD)in the CKD patient. 2. Discuss the prevalence of MBD in the kidney transplant recipient. 3. Describe the methods of diagnosing MBD, goals of management and monitoring parameters. 4. Recommend non-pharmacological and pharmacological treatment of MBD. 5. Discuss the pathophysiology of anemia both pre- and post-renal transplant. 6. Describe the goals of therapy and pharmacological management of anemia. 7. Describe the conflicting data on target hemoglobin with the use of erythropoiesis stimulating agents. 8. Describe the various methods of estimating GFR in the renal allograft recipient. 9. Discuss the use of potentially nephrotoxic medications in the renal allograft recipient and how to minimize nephrotoxicity. 10. Discuss how the varying degree of renal insufficiency affects the pharmacokinetics and pharmacodynamics of the immunosuppressants. Self-Assessment Questions Self-assessment questions are available online at Annual Meeting Long-term Management of the Renal Transplant Recipient 2

3 Anemia Pre- and Post-Renal Transplant Shouldn t the Allograft Be the Cure? Conflicts of Interest Speaker s Bureau for Amgen Joanna Hudson, Pharm.D., BCPS, FASN Associate Professor Departments of Clinical Pharmacy & Medicine (Nephrology) The University of Tennessee Memphis, TN Objectives Erythropoiesis in CKD Discuss the pathophysiology of anemia both pre- and post-renal transplant Bone Marrow Erythropoietin Iron Circulation Describe the goals of therapy and pharmacological management of anemia Describe the conflicting data on target hemoglobin with the use of erythropoiesis stimulating agents Stem Cell BFU-E CFU-E Proerythroblast Reticulocyte Time to Mature Cell Development (days) RBCs JH Brook et al. Iron Metabolism in Health and Disease. 1 st edition. London, England: W.B. Saunders; ietin (U/liter) Plasma Erythropoi Response to RBC Mass Normal Kidney Function Patients with Anemia and Normal Blood Donors Normal Blood Donors Patients with Anemia Hematocrit Erslev AJ. N Engl J Med. 1991;324: ietin (U/liter) Plasma Erythropoi Kidney Disease Patients on Dialysis Patients with Kidneys Patients without Kidneys Hematocrit Contributing Factors of Anemia Associated With CKD Erythropoietin deficiency & resistance Chronic blood loss Shortened RBC lifespan from 120 to ~60 days Iron losses (iron deficiency) GI bleeding Reduced intake & absorption Malnutrition Inflammatory conditions Hemodilution Secondary Hyperparathyroidism Other disease states (e.g. cancer, HIV) Long-term Management of the Renal Transplant Recipient 3

4 Body Iron Distribution and Pathways: Hemodialysis Patient Clinical and Economic Impact of Anemia Tissue Reticuloendothelial stores (low) ferritin 50 to 800 Transferrin Absorption 0.5 mg/day Gut Increased Mortality, Increased LVH 1-3 Decreased Quality of Life 4 Increased Hospitalization and Length of Stay 5 32 mg/day 200 mg 1.5 mg = 50 µg/% (20% sat) Erythroid marrow 36 mg/day Red blood cells 1500 mg (Hct 30) Adapted from Bothwell et al. Iron Metabolism in Man. 2nd ed Loss: 1 mg/day Loss: 4 mg/day Net loss: 4.5 mg/day 1. Harnett et al. Am J Kidney Dis. 1995;25(4 suppl 1):S3-S7. 2. Ma et al. J Am Soc Nephrol. 1999;10: Levin et al. Am J Kidney Dis. 1996;27: Strippoli et al. J Am Soc Nephrol. 2004;15: Jones et al. Kidney Int. 2004;65: e Risk *Relativ Lower HCT Associated With Increased Mortality in ESRD Patients All-cause death Cardiac-related related death < 27% 27% to < 30% 30% to < 33% 33% to < 36% *After adjustment for medical diseases. Ma et al. J Am Soc Nephrol ;10: Hct N = 75,283 Anemia Post Transplant At time of kidney transplantation almost all patients have anemia of CKD Post-transplantation anemia (PTA) is estimated to occur in 30-40% of patients Anemia usually resolves by 3-6 months, but some patients have late PTA defined as anemia 6 to 12 months after transplant Use of ESAs in kidney transplant recipients is relatively low Mechanisms of PTA Decreased RBC Production Drug induced (immunosuppressants, ACEIs/ARBs, antimicrobial agents) Allograft dysfunction and rejection Erythropoietin resistance (iron deficiency, infections, aplastic anemia) Loss of RBCs Surgical blood loss GI blood loss Frequent phlebotomy Mechanisms of PTA Increased RBC destruction Immune-mediated hemolysis (immunosuppression, PTLD) Microangiopathic hemolytic anemia (tacrolimus, cyclosporine, sirolimus) Nonimmune hemolysis (G6PD deficiency dapsone, trim/sufla, hemoglobinopathies) Other factors Donor and recipient factors Limitations of iron indices in transplant population Elevated hepcidin levels Long-term Management of the Renal Transplant Recipient 4

5 Immunosuppressive Medications and Anemia Antimetabolite medications (azathioprine, MMF, mycophenolic acid) bone marrow suppression mtor inhibitors (sirolimus, everolimus) myelosuppression and other mechanisms Hemolytic anemia with sirolimus and the calcineurin inhibitors tacrolimus and cyclosporine Role of Hepcidin in Iron Metabolism Hormone produced primarily in the liver Principal regulator or iron absorption and distribution into tissues hepcidin blocks iron absorption hepcidin increases iron absorption Iron deficiency, Increased erythropoiesis Hepcidin Hepcidin Inflammation, Increased iron stores Prevalence of PTA Prevalence of PTA Male Mild: Hb > g/dl Moderate: Hb > g/dl Severe: Hb 11 g/dl Vanrenterghem et al. Am J Transplant 2003;3:835. Female Hb > g/dl Hb > g/dl Hb 10 g/dl ESA therapy was used in 5.2% of patients overall and in 18% of patients with severe anemia. Vanrenterghem et al. Am J Transplant 2003;3:835. Prevalence of PTA Association with GFR Mix et al. Am J Transplant 2003;3:1426. Among pts with Hct < 30% 36% had iron studies 46% received iron 40% ESA Mix et al. Am J Transplant 2003;3:1426. Long-term Management of the Renal Transplant Recipient 5

6 Consequences in Transplant? Anemia significantly associated with mortality (hazard ratio 1.69; 95% CI ) 1 graft failure (hazard ratio 2.47; 95% CI ) 1 Left ventricular growth 2 Anemia not related to all-cause mortality but associated with 25% risk of allograft loss (hazard ratio 1.25; 95% CI ) 3 Consequences in Transplant? Not a clear consensus than anemia is associated with increased mortality and adverse CV events in transplant population Anemia may not directly cause adverse outcomes in transplant population, but may be a marker for an underlying pathologic process 1 Molnar et al. Am J Transplant 2007;7: Rigatto et al. J Am Soc Nephrol 2003;14: Winkelmayer et al. Nephrol Dial Transplant 2006;21:3559. Goals in Transplant Patient Approach to Prevention and Treatment QUALITY OF LIFE TRANSFUSIONS RISK OF ALLOGRAFT LOSS Perioperatively: Consider iron for patients with transferrin saturation < 20% and serum ferritin < 200 ng/ml Consider ESA therapy when benefit outweighs risk Balance goals while minimizing the risks of treatment. K/DOQI Guidelines for Anemia Management in the Transplant Population Recommend that treatment guidelines for anemia in the general CKD population be followed in the transplant population ESAs Early Post-transplantation Studies support that ESAs are effective in correcting anemia, although higher doses may be required compared to doses pre-transplant ESAs Late Post-transplantation ESAs are effective and do not likely accelerate a decline in renal function May contribute to hypertension Am J Kidney Dis. 2006;47(suppl 3):S1-S146. Guidelines for Anemia of CKD CKD diagnosis Hb <12 g/dl (females) Hb <13.5 g/dl (males) Hb < 1 g/dl 4 weeks after dose change Increase doses by 25% Evaluate RBC, reticulocytes, iron parameters Normal Erythropoietic Stimulating Agent (ESA) Measure Hb every week until stable, then every 4 weeks Iron deficient No Correct iron deficiency (oral, parenteral) Anemia corrected Hb > 1 g/dl in 2 wk period Decrease doses dose by 25% Adapted from: National Kidney Foundation. Am J Kidney Dis. 2001;37(suppl 1):S182-S237, Am J Kidney Dis. 2006;47(suppl 3):S1-S146 and Epoetin PI June Long-term Management of the Renal Transplant Recipient 6

7 What is known about ESAs in the transplant population? ESA therapy post-transplant shortens time to achieve higher hematocrit and improves QOL 1,2 Observational studies in kidney transplant show evidence of increase mortality with Hb levels above 12.5 g/dl 3 Medicare reimbursement polices affect therapy Questions about ESAs in the transplant population? Can we apply data from ESA studies in CKD population? When do we start treatment and how aggressive should we be? What is the target Hb? 1 Van Loo et al. Nephrol Dial Transplant 1996;11: McDevitt et al. Am J Transplant 2005;5: Heinze et al. BMJ 2009;339:b4018. Mean monthly hemoglobin & mean EPO dose per week Concerns with ESAs and Target Hb in CKD United States Renal Data System (USRDS) 2006 Annual Data Report Safety Information on ESAs: Supporting Studies WARNINGS: Increased Mortality and Serious Cardiovascular Events CHOIR Trial Primary endpoints: time to composite death, MI, stroke, death, CHF hospitalization 1432 patients enrolled Study Patients Sponsor Published Besarab et al 1 Epoetin alfa Cardiac disease on hemodialysis Amgen 1998 Target Hb (g/dl) 14 ± 1 * vs 10 ± assigned to high-hb group 717 assigned to low-hb group (13.5 g/dl) (11.3 g/dl) CHOIR 2 Epoetin alfa CREATE 3 Epoetin beta Anemia associated with CKD not on dialysis Anemia associated with CKD not on dialysis 1. Besarab A, et al. N Engl J Med. 1998;339: Singh AK, et al. N Engl J Med. 2006;355: Drüke, et al. N Eng J Med 2006:355: Ortho Biotech/ J & J F. Hoffmann La Roche * vs g/dl vs g/dl CHOIR = Correction of Hemoglobin and Outcomes in Renal Insufficiency CREATE = Cardiovascular Risk Reduction by Early Anemia Treatment with Epoetin Beta 312 completed 36 months or withdrew at study termination without having primary event 125 had a primary event 278 withdrew before early termination of study 131 required renal replacement therapy (RRT) 147 withdrew for other reasons 349 completed 36 months or withdrew at study termination without having primary event 97 had a primary event 271 withdrew before early termination of study 111 required RRT 160 withdrew for other reasons Singh AK, et al. N Engl J Med. 2006;355: Long-term Management of the Renal Transplant Recipient 7

8 CHOIR Study Singh AK, et al N Engl J Med. 2006;355(20): Primary Composite End Point N = High-hemoglobin group ability of site Event Proba Compos Low-hemoglobin group Month 222 composite events (death, MI, hospitalization for CHF, stroke) High-Hb (13.5 g/dl): 125 events (18%) Low-Hb (11.3 g/dl): 97 events (14%) Hazard ratio (HR) = 1.34; 95% Confidence Interval (CI), 1.03 to 1.74 (P = 0.03) CREATE Study 603 patients with CKD stage 3 or 4 randomly assigned to 1 of 2 groups: Epoetin beta therapy targeted to Hb g/dl Epoetin beta therapy targeted to Hb g/dl Primary endpoint was time to first cardiovascular asc eventent Secondary endpoints were LVMI, QOL, and progression of CKD Drüeke TB, et al, for the CREATE Investigators. N Engl J Med. 2006;355(20): Hemoglo obin (g/dl) Median Hemoglobin Levels in the Intention-to-Treat Population During the Study Months Group 1 (n=301) Group 2 (n=302) Drüeke, T. et al., N Engl J Med 2006;355: Event-Free Survival (%) Time to Primary End Point of First Cardiovascular Event Group 2 Lower Hb Group 1 Higher Hb 58 events in group 1 vs. 47 events in group 2 Hazard ratio 0.78; 95% CI 0.53 to 1.14; P = Month Drüeke, T. et al., N Engl J Med 2006;355: CREATE Study Meta-Analysis of CKD Trials There was no difference between the groups in the primary endpoint, LVMI, or progression of CKD QOL increased significantly ifi in both groups, but was significantly better in the higher Hb group compared with the lower Hb group at yr 1 p= Drüeke TB, et al, for the CREATE Investigators. N Engl J Med. 2006;355(20): Phrommintiku, Haas, Elsik, Krum. Lancet 2007; 369: Long-term Management of the Renal Transplant Recipient 8

9 FDA Reaction to Safety Information on ESAs FDA issued warning in late 2006 regarding new risks associated with use of ESAs FDA changed labeling for ESA on March 9, 2007 The use of ESAs may increase the risk for death and for serious cardiovascular events when dosed to achieve a target hemoglobin of >12 g/dl Black Box Warning for ESAs in CKD Renal failure: Patients experienced greater risks for death and serious cardiovascular events when administered erythropoiesisstimulating agents (ESAs) to target higher versus lower hemoglobin levels (13.5 vs g/dl; 14 vs. 10 g/dl) in two clinical studies. Individualize dosing to achieve and maintain hemoglobin levels within the range of 10 to 12 g/dl. FDA recommends using the lowest dose of ESAs that will gradually raise the hemoglobin concentration to the lowest level sufficient to avoid the need for blood transfusion FDA Web page. Information for healthcare professionals: erythropoiesis stimulating agents (ESA). Available at: Accessed April 5, Epogen PI, Amgen Inc. - August 2008 K/DOQI Update of Hb Target TREAT: Trial to Reduce Cardiovascular Events with Aranesp (Darbepoetin alfa) Therapy Lower limit of Hb (Recommendation) Upper limit of Hb (Guideline) Adequate Hb In dialysis and nondialysis CKD patients receiving ESA therapy, the selected Hb target should generally be in the range of g/dl In dialysis and nondialysis CKD patients receiving ESA therapy, the Hb target should not be above 13 g/dl Strength of evidence = moderate Study Population Hb 11 g/dl GFR ml/min Type 2 DM TSat 15% Hypothesis: Treatment of anemia with darbepoetin reduces the risk of mortality and cardiovascular events and ESRD in patients with CKD and type 2 diabetes N = 4038 N = 2012 N = 2026 Darbepoetin Group (Target Hb 13 g/dl) Design randomized (1:1), double blind, controlled Control Group Placebo group subjects could receive darbepoetin when Hb < 9 g/dl KDOQI. Am J Kidney Dis. 2007;50: Pfeffer et al. N Eng J Med 2009;361: TREAT Endpoints Primary Endpoints Time to: Composite outcome of death from any cause or a CV event defined as: Nonfatal myocardial infarction Congestive heart failure Stroke Hospitalization for myocardial ischemia TREAT End Points Composite of death or ESRD Secondary Endpoints Time to: Death Death from CV causes Rate of decline in egfr Change in patient reported fatigue (FACT-fatigue) Pfeffer et al. N Eng J Med 2009;361: Pfeffer et al. N Eng J Med 2009;361: Median Hb 12.5 ( ) 12.8) in darbepoetin group; 10.6 ( ) in placebo group (p<0.0001). Long-term Management of the Renal Transplant Recipient 9

10 TREAT TREAT failed to meet its primary objectives of demonstrating a reduction in all-cause mortality, CV morbidity, or ESRD and in time to all-cause mortality or ESRD. There was an almost two-fold increase in risk of stroke (5% in treatment arm vs. 2.6% in placebo arm) Among darbepoetin treated subjects with a past history of cancer, there were more deaths due to all causes and due to cancer compared with the control group FDA Urges Lower Doses of Anemia Drugs Reported that the FDA "said that three drugs that had been widely used to treat anemia in both kidney and cancer patients were so dangerous to the heart that doctors should consider avoiding the medicines altogether in some patients and using less of them in others." The FDA "concluded that there were no risk-free doses of Epogen (epoetin alfa), Aranesp (darbepoetin alfa) and Procrit (epoetin alfa), and that doctors should use the medicines only in patients suffering from severe anemia. New York Times (6/24/2011) Most Recent Black Box Warning for ESAs in CKD Chronic Kidney Disease: In controlled trials, patients experienced greater risks for death, serious adverse cardiovascular reactions, and stroke when administered erythropoiesisstimulating agents (ESAs) to target a hemoglobin level of greater than 11 g/dl. No trial has identified a hemoglobin target level, ESA dose, or dosing strategy that does not increase these risks. Use the lowest Epogen dose sufficient to reduce the need for red blood cell (RBC) transfusions. Physicians and patients should weigh the possible benefits of decreasing transfusions against the increased risks of death and other serious cardiovascular adverse events. For patients with CKD on dialysis: Labeling of ESAs Initiate Epogen treatment when the hemoglobin level is less than 10 g/dl. If the hemoglobin level approaches or exceeds 11 g/dl, reduce or interrupt the dose For patients with CKD not on dialysis: Consider initiating Epogen treatment only when the hemoglobin level is less than 10 g/dl and the following considerations apply: The rate of hemoglobin decline indicates the likelihood of requiring a RBC transfusion and, Reducing the risk of alloimmunization and/or other RBC transfusion-related risks is a goal If the hemoglobin level exceeds 10 g/dl, reduce or interrupt the dose of Epogen, and use the lowest dose of Epogen sufficient to reduce the need for RBC transfusions. Epogen PI, Amgen Inc. June 2011 Epogen PI, Amgen Inc. June 2011 Questions Are negative outcomes associated with ESAs specifically or Hb level or both? What is the Hb level at which QOL is maximixed, yet risk is minimized? Is iron a contributing factor or would increased use be supported to achieve target Hb without increased use of ESAs? What to do with conflicting FDA warnings and K/DOQI anemia guidelines? Considerations in the Transplant Population Consider the risk of CV events and stroke in transplant recipients before initiating an ESA If blood transfusions are likely to be needed given the decline in Hb consider potential benefit of ESAs at low Hb (< 10 g/dl?) Until further guidance is available in the transplant population consider recommendations for ESA use in CKD patients not on dialysis Long-term Management of the Renal Transplant Recipient 10

11 Summary Anemia of CKD is prevalent in patients post-kidney transplant and a problem many practitioners will be faced with given the increase in the population with ESRD. Iron supplementation and ESAs are essential for treatment of anemia of CKD; however, practitioners need to be cognizant of the limitations in using these agents. Recent evidence of mortality risk associated with higher Hb in select populations has raised many questions about the current strategies for anemia management. Whether the same risks of ESA use observed in the CKD population apply to kidney transplant patients has not been determined; however, there is enough information on ESAs to justify caution when making treatment decisions for individuals with anemia post transplant. Long-term Management of the Renal Transplant Recipient 11