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Monitoring and treatment iron overload in thalassaemia. Professor John Porter Red Cell Disorders Unit University College London Hospitals and UCL j.porter@ucl.ac.uk. M onitoring and treatment iron overload in thalassaemia. Professor John Porter Red Cell Disorders Unit
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Monitoring and treatment iron overload in thalassaemia Professor John Porter Red Cell Disorders Unit University College London Hospitals and UCL j.porter@ucl.ac.uk
Monitoring and treatment iron overloadin thalassaemia Professor John Porter Red Cell Disorders Unit University College London Hospitals and UCL j.porter@ucl.ac.uk
Outline • What are the treatment and monitoring options available for iron overload in Thalassaemia Major • On what are guidelines about ferritin targets based and should we be more ambitious? • What are the goals of chelation treatment ? • How can monitoring help to achieve these goals? • What can be achieved ?- a personal perspective
Monitoring options • Iron loading rate • Serum ferritin • Liver Iron concentration • Cardiac evaluation – function & T2* • Endocrine evaluation – growth, function & MRI • Adherence and quality of life
Highly variable iron excretion is required tobalance transfusional iron loading in Thalassaemia Major • Iron accumulation from transfusion in TM (n = 586) • 233mls/kg/y blood (if Hct 0.6) • about 40 units/year for a 70 kg person • 0.4 ± 0.11 mg/kg/day (mean) of iron • < 0.3mg /kg day 19% of patients • 0.3-0.5 mg/kg/day 61% • > 0.5 mg/kg/day 20% Cohen,Glimm and Porter. Blood 2008;111:583-7
Dosing to balance iron transfusional rate D eferoxamine Average transfusion iron intake thalassaemia Average transfusion iron intake SCD Studies 107 and 108 0.8 Deferasirox 0.7 0.6 0.5 Mean total body iron excretion ± SD (mg Fe/kg/day) 0.4 0.3 0.2 0.1 Actual doses (mg/kg/day) 0 0 5 10 15 20 25 30 Deferasirox Deferoxamine (5 days/week) 0 10 20 30 40 50 60 Cohen AR, et al. Blood. 2008;111:583-7.
Change in LIC at low defarasirox doses in NTDT • mean loading rate 0.01 mg/kg/day (primarily from increased GI absorption) LIC change (mg/g dry wt) from baseline Ferritin change (ng/ml) from baseline Taher, Porter,. et al Blood (2012) , 120, 970-7, But at 10mg/kg/day, the mean LIC increased at 1y in TM with mean loading rate 0.4mg/kg/day Cappellini et al, Blood. 2006;107:3455-3462
Use serum ferritin measures to achieve harmless body iron levels? • Clear evidence linking long-term ferritin control to outcome • Convenience and low cost • Permit frequent repeated measurements • Allows early trend recognition • Ferritin trend is increasing; • focus on adherence • consider dose increase • chelator regime change • Ferritin trend decreasing • If rapid, dose adjust to minimise risks of over chelation for ‘soft landing’ • If levels already low- dose reduction to allow maintenance of current level
Limitations of just using serum ferritin ? • Variability in LIC accounts for only 57% of variability in serum ferritin 1 • Raised by inflammation or tissue damage • Lowered by vitamin C deficiency 2 • Origin of serum ferritin differs above values of 4K 3 • Relationship of ferritin to body iron (LIC) varies in different diseases • Low relative to LIC in ThalIntermedia4 • (hepatocellular > macrophages) • Higher and variable in SCD 5 • Relationship of ferritin to LIC differs with different chelators,6,7 • Brittenham et al, Am J Hematol 1993;42:81-5 • Chapman et al, J ClinPathol 1982;35:487-91. • Worwood, M. 1980 Br J Haematol 46,409-16 • Origa, Hamatologica 2007, 92 583 • 5. Porter & Huehns, ActaHaematologica • Fischer et al. Brit J Haem 2003, 121 938-948 • Ai LeenAng, et al, Blood, 201, 116, Abstract 4246.
Why monitor& control liver iron ? • Ferritin alone may not reflect true body iron and chelation trends • LIC predicts total body storage iron in TM1 • Absence of pathology • heterozygotes of HH where liver levels < 7 mg/g dry weight • Liver pathology • abnormal ALT if LIC > 17 mg/g dry weight2 • liver fibrosis progression if LIC > 16 mg/g dry weight3 • Cardiac pathology at high levels • Increased LIC linked to risk of cardiac iron in unchelated patients 2,6 • LIC >15 mg/g dry weight association with cardiac death • all of 15/53 TM patients who died4 • improvement of subclinical cardiac dysfunction with venesectionalone post-BMT5 AngelucciE, et al. N Engl J Med. 2000;343:327-31. Jensen PD, et al. Blood. 2003;101:91-6. AngelucciE, et al. Blood. 2002;100:17-21. BrittenhamGM, et al. N Engl J Med. 1994;331:567-73. MariottiE, et al. Br J Haematol. 1998;103:916-21. Buja LM, Roberts WC. Am J Med. 1971;51:209-21 ALT = alanine aminotransferase; BMT = bone marrow transplantation.
Low Heart T2* inreases risk of low LVEF 90 80 70 60 50 40 30 20 10 0 LVEF (%) Severe cardiac iron Minimal liver iron Severe liver iron Minimal cardiac iron 0 20 40 60 80 Heart T2* (ms) LVEF = left ventricular ejection fraction. Anderson et al. Eur Heart J. 2001;22:2171.
Relationship between cardiac T2* and cardiac failure 0.6 0.5 0.4 0.3 0.2 0.1 0 0 30 60 90 120 150 180 210 240 270 300 330 360 < 6 ms 6–8 ms Proportion of patients developing cardiac failure 8–10 ms > 10 ms Follow-up time (days) Kirk P, et al. Circulation. 2009;120:1961-8.
Other Approaches to assessing Iron overload • Effects on specific organs • Other Organs • Endocrine screening- assessment of function • Growth monitoring, bone age • Role of MRI screening of pancreas 1, 2? • Measurement of NTBI/LPI • Predictive value of response 3 Au WY, et al. Haematologica. 2008;93:785. Noetzli LJ, et al. Blood. 2009;114:4021-6. 3. AydinokY, et al. . Haematologica, 2012, 97,6, 835-41
Au WY, et al. Haematologica. 2008;93:785. MRI and assessment of endocrine complications in Thalassaemia Major – = not analysed; EF = ejection fraction; NS = not significant; Pan = pancreatic; Pit = pituitary; SIR = signal intensity ratio of pituitary to muscle. *p < 0.05; **p < 0.01; ***p < 0.001. n=180 • Cardiac MRI T2* correlates with endocrine dysfunction • Pancreatic T2* poor correlation with diabetes • Pituitary T2 correlates with multiple endocrine dysfunctions
Assessment – when? Observation Frequency Expense Iron intake rate Each transfusion Chelation dose & frequency 3 monthly Growth & sexual development 6 monthly children Liver function 3 monthly Sequential ferritin 3 monthly GTT, thyroid, Ca metab Yearly in adults Liver iron Yearly from age 8-10 Heart function Yearly from age 8-10 Heart iron (T2*) Yearly from age 8-10
Goals of chelation therapy • Prevention of iron mediated damage • Balance input and output - iron balance • Achieve harmless levels of body iron safely • Rescue • patients with high levels of body iron • patients with high levels of cardiac iron • patients with heart dysfunction
Chelation regimes • DFO monotherapy • Sc 8-12h • continuous (sc or iv) • Deferiprone monotherapy • po 3 x daily • Combined Deferiprone and DFO • Deferiprone daily with DFO nocte n x week • Deferiprone daily + DFO at same time • Deferasirox monotherapy • New combinations and drugs
‘Harmless body iron levels’ ?what are guidelines based on ? • Experience with thalassaemia major • Experience with DFO • Control of ferritin and LIC • links to risk of cardiac disease • risk of under and over chelation
Guidelines with DFO therapy • Begin • after 10–20 blood transfusions • or when serum ferritin > 1,000 µg/L • Dose adults 40-60mg/kg 8-12h nocte minimum 5x/wk • Maintain • serum ferritin < 2,500 µg/L (1,000 µg/L recommended) • LIC < 7 mg/g dry weight • Intensify dose or frequency if • if severe iron overload • High ferritin values persistently > 2,500 µg/L • High liver iron > 15 mg/g dry weight • or significant cardiac disease • Significant cardiac dysrhythmias • Evidence of failing ventricular function • Evidence of severe cardiac iron loading • Reduce dose if • Ferritin <1000µg/L • Ratio of mean daily dose (mg/kg) / ferritin >0.025
Guidelines based on Risks of over-chelation with DFO • Risks of starting too early • effects on growth • effects on bones, especially < 3 years of age1,2 • Risks of too high a dose • growth affected: > 70 mg/kg/day, normalized ≤ 40 mg/kg/day3 • skeletal/bones: > 70 mg/kg in children1 • eyes: visual symptoms > 80 mg/kg/day4 • otoxicity4,5 • Risks at low iron loads • effects on growth: patients had mean ferritin of 1,300 µg/L3 • otoxicity: with serum ferritin < 2,000 µg/L or when ratio dose/ferritin too high5 • neurotoxicity in non-iron-overloaded RA patients at low doses6 • ocular toxicity in dialysis patient7 1. Olivieri NF, et al. Am J PediatrHematolOncol. 1992;14:48-56. 2. Brill PW, et al. Am.J.Roentgenol. 1991;156:561-5. 3. Piga A, et al. Eur J Haematol. 1998;40:380-1. 4. Olivieri NF, et al. N Engl J Med. 1986;314:869-73. 5. Porter JB, et al. Br J Haematol. 1989;73:403-9. 6. Blake DR, et al. Q J Med. 1985;56:345-55. 7. Rubinstein M, et al. Lancet. 1985;325:817-8.
DFO Chelation therapy has improved patient survival in TM 1985–1997 1.00 1980–1984 1975–1979 1970–1974 0.75 Birth cohort Survival probability 0.50 1965–1969 1960–1964 0.25 (p < 0.00005) 0 0 5 10 15 20 25 30 Age (years) Borgna-Pignatti C, et al. Haematologica. 2004;89:1187-93.
Decline in complications withiron chelation Patients with β-thalassaemia major born after 1960 (N = 977) *DFO i.m., 1975; †DFO s.c., 1980. In 1995, 121 patients switched to deferiprone (censored at this time) Borgna-Pignatti C, et al. Haematologica. 2004;89:1187-93.
Is there a risk of over-chelation with other chelation regimes?How low can we go? • How is risk of chelator toxicity related to • Absolute chelator dose • Dose in relation to • Body iron load • Transfusional iron loading rate • Rate of decrease of load with chelation
Do DFP doses >75mg/kg/d affect tolerability? Unwanted Effect Dose dependence? GI distrurbances 3-24% at 75mg/kg (1-3) 66% at 100mg/kg (n=29) (4) Neutropaenia insufficient human numbers Agranulocytosis insufficient human numbers Thrombocyopenia age <6y (7/44) ? dose effect (5) Arthropathy ? improved arthropathy at 50mg/kg (6) Neurotoxicity Yes with unintended large doses 1. Al Rafae Brit J Haematol, 1995;91:224-9.2. Ceci A, et al. Br J Haematol. 2002;118: 330-6. 3. Cohen AR, et al. Br J Haematol. 2000;108:305-12. 4. Pennell DJ, et al. Blood. 2006;107:3738-44 5. Naithani et al, Eur J Haematol. 2005 ;74:217-20 6. Lucal et a, Ceylon Med, 45, 71-4.J 2000 .
Low serum ferritin without toxicity with long-term combined therapy • 53 patients 5-7y on DFO 20-60mg/kg/day and deferiprone 75mg/kg/day ‘individually tailored’ • Ferritin bl3421µg/L - 87 µg/L at 5-7y • T2* bl28ms - 38 ms at 5-7y • LIC bl12.7 - 0.8mg/g dry wt at 5-7y • GTT normalbl 23% - 64% at 5-7y • Thyroxinereplacement bl34% - 20% at 5-7y • Secondary amen bl19/26 - 3/19 spontaneous ovulation • No toxicity Farmaki et al presentation at ITC 2008 FC07 Pg. 92 Farmaki et al Br J Haematol, 466-75 (2010)
Year 1 Year 2 Year 3 Year 4 Year 5 Experience with serum ferritin < 1,000 μg/L • % of patients achieving serum ferritin < 1,000 µg/L Years The incidence of drug-related AEs did not appear to increase during the periods after serum ferritin levels first decreased < 1,000 μg/L 174 adult and paediatric patients (out of 474) were chelated to serum ferritin levels < 1,000 μg/L Porter JB, et al. Blood. 2008;112:[abstract 5423].
Safety profile of serum ferritin <1000 μg/L • The incidence of drug-related adverse events did not appear to increase during the periods after serum ferritin levels first decreased < 1,000 μg/L • Safety profile was similar to patients with serum ferritin levels > 1,000 μg/L • No increase in the proportion of patients with creatinine increases > 33% above baseline and ULN or with ALTs > 10 x ULN ALT = alanine transaminase. Porter JB, et al. Blood. 2008;112:[abstract 5423].
Combined chelation therapy with DFX and DFO in transfusion-dependent thalassaemia Aim: to explore safety and efficacy of combined deferasirox and DFO in patients with transfusion-dependent thalassaemia who had failed standard chelation therapy with single drug (US24T) 15 patients enrolled and randomized into 3 equally sized groups Group AAdultsLIC <15 mg/g dry wt Group C8–18 yearsLIC >5 mg/g drywt Group BAdultsLIC >15 mg/g dry wt Duration of therapy: 52 weeks Deferasirox 20–30 mg/kg/day DFO 35–50 mg/kg/infusion infused 3–7 days/week Lal, Porter, et al. Blood. 2010;116:[abstract 4269].
3 2,000 1,500 2 1,000 1 500 0 0 DFX + DFO:improvements in iron overload Cardiac improvements (in three patients who had T2* < 20 ms at baseline) • T2* < 20 ms at baseline (6.5–19.5 ms): improved +2.43 ms (8.8–21.3 ms) (p= 0.027) • LVEF < 60% at baseline (47.4–58.1%): improved to 60.6–64.4% • Median LPI decreased: 0.87 µM to 0.05 µM (p= 0.004) LIC NTBI Serum ferritin 15 43% (p = 0.008) p < 0.001 48% (p = 0.003) 10 Median serum ferritn (μg/L) Median plasma NTBI (µM) Median LIC (mg/g) 5 0 BL 1 year BL 1 year DFO DFO + deferasirox LPI = labile plasma iron. Lal A, et al. Blood. 2010;116:[abstract 4269].
DFX + DFO:improvements in iron overload Lal, Porter et al Blood.CellsMol Dis. 2012 in press.
34-year-old female with TM, 2 units of packed red blood cells, every 20 days Deferoxamine – failed to comply T2* liver 1.1 ms, cardiac T2* 9.4 ms serum ferritin > 2,800 µg/L Deferasirox, 20 mg/kg for 12 months liver T2* 3.33 ms, cardiac T2* 10.6 ms Deferasirox 30 mg/kg for 24 months liver 7.81 ms, cardiac T2* 13.8 ms serum ferritin 2,080 µg/L Deferasirox 30 mg/kg/day + deferiprone 75 mg/kg/day for 12 months serum ferritin 397 μg/L liver T2* 15.3 ms, cardiac T2* 21.1 ms 25 20 15 10 5 0 DFP + DFX?A patient case Combination MRI T2* (ms) Cardiac Liver 2005 2006 2007 2008 2009 2010 Year Serum ferritin 3,000 2,500 2,000 Serum ferritin (µg/L) 1,500 1,000 500 0 2005 2006 2007 2008 2009 2010 Year Voskaridou E, et al. Br J Haematol. 2011;154:654-6.
Patient selection 16 TM > 20 years old Either intolerance to DFO or ‘inconvenience to DFO’ Serum ferritin > 500 µg/L > 1 iron overload complication (clinical or laboratory) Treatment: up to 2 years of DFX (20–25 mg/kg/day) + DFP (75–100 mg/kg/day) Outcome Reversal of cardiac dysfunction in 2/4 Mean LVEF increased significantly GTT improved in 2/8 with impaired GTT Improvement in gonadal function Tolerability No serum creatinine > ULN No agranulocytosis, neutropenia, thrombocytopenia 3/15 (20%) minor GI disturbance DFP + DFX GTT = glucose tolerance test. * p < 0.001 Farmaki, et al. Blood Cells Mol Dis. 2011;47;33-40.
How has chelation therapy and monitoring impacted on outcome in transfusion dependent thalassaemia- a local perspective in UK
Treatment of Thalassaemia Major in the UK 1960 → 1970 → 1980 → 1990 → 2005 • Cardiac failure secondary to cardiac iron overload is reported as the leading cause of death amongst patients with TM • Survival substantially improved with introduction of iron chelation therapy but despite this by 2000, 50% UK patients died before the age of 35 in 20001. • CMR introduced in London 1999 – what impact has this had • Cohort of 121 patients monitored and treated at UCLH/Whittinton since 1999 1980 – SC desferoxamine standard of care 1987 – Deferiprone 1964 – IM desferoxamine 1999 – CMR Deferasirox 1984 – Bone marrow transplant initiated
Chelation regimes DFP + DFO DFX DFP DFX DFO DFO DFP + DFO DFP + DFO DFP DFP 2010
70 60 50 40 30 20 10 0 T2* ≤ 20 ms T2* < 10 ms Impact of a decade of cardiac MRI assessment on cardiac T2* Cohort of 132 patients from UCLH/Whittington hospitals p < 0.001 60 Baseline Median 9 years follow-up Proportion of patients (%) p < 0.001 23 17 7 Thomas AS, et al. Blood. 2010;116:[abstract 1011].
Mortality • Total of 8 deaths amongst 132 patients: • 2 female, 6 male • median age at death 35.6 years (range 27.3-48.4) • None directly related to myocardial iron • Mortality rate 1.65 / 1000 patient y (95% CI 0.71-3.24) • Previous reports from UK thalassaemia registry: • 1980-1999: 12.7 deaths / 1000 patient y 2 • 2000-2003: 4.3 deaths / 1000 patient y 3 1. Thomas AS, et al. Blood. 2010;116:[abstract 1011] 2 Modell et al , Lancet 355:2051-2, 2000 3. Modell et al , J. Cardiovas Magnetic Resonance, 2008
Causes of Death and cardiac MRI • Cardiac MRI at death, n = 8 • T2* > 20ms • 3 pt with hepatitis C complications • 1 sudden death • T2* 10-20ms • 1 pt with meningitis • 1 pt with cancer • T2* < 10ms • 2 pt with sepsis
Chelator regime at death • DFO (n= 4) • DFP (n= 2) • Combination DFP + DFO ( n= 1) • DFX ( n= 1)
Causes of death in β-thalassaemia major in the UK 100 90 80 70 60 50 40 30 20 10 0 1950–1959 1960–1969 1970–1979 1980–1989 1990–1999 2000–2003 This cohort Hepatitis C complications Other/unknown Malignancy Infection BMT complication Anaemia Iron overload Patients (%) Mortality rates per cohort Use of modern iron chelation therapy and regular CMR monitoring has dramatically reduced the iron overload-related mortality in the Red-cell Disorders Unit Adapted from UK Thalassaemia Registry data from Modell B, et al. J Cardiovasc Magn Reson. 2008;10:42.Thomas AS, et al. Blood. 2010;116:[abstract 1011]. BMT = bone marrow transplantation;CMR = cardiac magnetic resonance imaging
Optimal Outcome - What else do we need ? • Optimal monitoring and intensification for high risk patients • Recognition that chronic diseases pose special challenges which require targeted resources • Rapidaccess to free care • Staff with expert knowledge & experience • Continuity of care (especially staff) • Systemsorganized to allow best care with minimum disruption to ordinary life • Identity (a ‘unit’) for patients allowing a focus for care but not isolated from hospital • Multidisciplinaryteam with integrated clinics & investigations AND
Conclusions • With modern chelation regimes, used alone or in combination and when applied with modern monitoring techniques, excellent survival can be obtained • The challenge over the next decade will to be to improve quality of life in an ageining population by; • Further decreasing morbidities associated with thalassaemia and iron overload • Further improving infrastructure and delivery of care to thalassaemia patients inside and outside treatment ‘centres’
What can be achieved with transfusion, chelation and optimal monitoring Then andNow
A decade of cardiac monitoring with modern chelation therapies for TM, UCLH/Whittington • Cohort of 132 patients received 1st CMR 1999-2000 • 109 of these available for long term CMR FU • Follow up median 9.2 years (range 7.0-10.6) • Minimum CMR follow up of 7 y • Median age at 1st CMR 27.9 years (range 7.7-49.5) • 58 female, 51 male
Variables studied • % Patients with evidence of myocardial iron • At 1st CMR • At latest CMR • Survival in cohort with baseline CMR 1999-2000 • Cause of death • T2* at death • Modes of chelation • At baseline • At latest follow up • At death • Number of switches in chelator
Causes of Death by cardiac MRI • Cardiac MRI at death, n = 8 • T2* > 20ms • 3 pt with hepatitis C complications • 1 sudden death • T2* 10-20ms • 1 pt with meningitis • 1 pt with cancer • T2* < 10ms • 2 pt with sepsis
Changes in Chelation 69% changed chelator at least once based on: • Iron assessment • Ferritin trend • LIC trend • m T2* trend • Side effects/tolerability • Adherence or patient preference • Availability of new chelators: trials/funding decisions