From www.bloodjournal.org by guest on June 4, 2018. For personal use only .
`
`.v
`
`RED CELLS
`
`Randomized controlled trial of deferiprone or deferoxamine in beta-thalassemia
`major patients with asymptomatic myocardial siderosis
`Dudley J. Pennell , Vasili Berdoukas, Markissia Karagiorga, Vasili Ladis, Antonio Piga, Athanassios Aessopos, Efstathios D. Gotsis,
`Mark A. Tanner, Gill C. Smith, Mark A. Westwood, Beatrix Wonke, and Renzo Galanello
`
`Most deaths in beta-thalassemia major
`result from cardiac complications due to
`iron overload. Differential effects on myo(cid:173)
`cardial siderosis may exist between differ(cid:173)
`ent chelators. A randomized controlled
`trial was performed in 61 patients previ(cid:173)
`ously maintained on subcutaneous defer(cid:173)
`oxamine. The primary end point was the
`change in myocardial siderosis {myocar(cid:173)
`dial T2*) over 1 year in patients main(cid:173)
`tained on subcutaneous deferoxamine or
`those switched to oral deferiprone mono(cid:173)
`therapy. The dose of deferiprone was 92
`mg/kg/d and deferoxamine was 43 mg/kg
`
`for 5.7 d/wk. Compliance was 94% ± 5.3%
`and 93% ± 9.7% (P = .81), respectively.
`The improvement In myocardial T2* was
`significantly greater for deferiprone than
`deferoxamine (27% vs 13%; P = .023).
`Left ventricular ejection fraction increased
`significantly more in the deferiprone(cid:173)
`treated group (3.1 % vs 0.3% absolute
`units; P = .003). The changes in liver iron
`level (-0.93 mg/g dry weight vs -1.54
`mg/g dry weight; P = .40) and serum fer(cid:173)
`ritin level (-181 µg/L vs -466 µg/L;
`P = .1 6), respectively, were not signifi(cid:173)
`cantly different between groups. The most
`
`frequent adverse events were transient
`gastrointestinal symptoms for deferiprone(cid:173)
`treated patients and local reactions at the
`infusion site for deferoxamine. There were
`no episodes of agranulocytosis. Deferiprone
`monotherapy was significantly more effec(cid:173)
`tive than deferoxamine over 1 year in improv(cid:173)
`ing asymptomatic myocardial siderosis in
`beta-thalassemia major. (Blood. 2006;107:
`3738-3744)
`
`© 2006 by The American Society of Hematology
`
`Introduction
`
`Iron-induced heart failure and arrhythmia are the most common
`causes of death in beta-thalassemia major, accounting for up lo
`71 % o f deaths in older series1·3 and 67% of deaths in a more recent
`report, despite improvements in overall survival.4 There is a need
`therefore to identify myocardial siderosis early and improve
`treatments for heart complications. Myocardial siderosis can be
`identified by cardiovascular magnelic resonance (CMR) measure(cid:173)
`ment of myocardial T2*, which is highly sensitive to tissue iron
`concentration, and this has been validated in the United Kingdom5·6
`and independently in the United States.7 Palients having increased
`myocardial siderosis have been shown to be at increased risk of left
`ventricul ar (LV) systolic and diastolic dysfunction,5·7-9 arrhyth(cid:173)
`mias,7 and heart fai lure.5·10 In one series, patients presenting with
`heart failure had a ~ean T2* of 5.1 ms, 11 which is substantially
`below the normal lower limit of26 his,5 and another series showed
`89% of patients presenting in heart failure having a T2* less than
`l 0 ms. 10 Myocardial T2* in non- iron loaded individuals is not
`affected by impaired LV function, age, or infarction. 12 The T2*
`technique is fast13 and is highly reproducible between different MR
`scanners.5· 14•17 T2* calibration has been achieved for the liver in
`humans and5•1s in the heart in animals 19 and wi ll soon be available
`
`for the human heart. 20 Therefore, myocardi al T2* can currently be
`used to determine changes in human myocardial iron but not the
`absolute myocardial iron concentration. The T2* technique shows
`improvement in myocardial sidcrosis in response to intravenous
`deferoxamine treatment in acute heart failure, 11 and a case(cid:173)
`controlled study found significantly less myocardial siderosis and
`improved LV ejection fraction (EF) in tbalassemia patients treated
`with deferiprone compared with deferoxamine. 21 These data sug(cid:173)
`gest that myocardi al T2* has value for comparing the cardiac
`efficacy of chelators. We therefore compared these 2 treatments as
`monotherapy in a prospective multicenter. randomized, controlled
`trial , using the change over 1 year in myocardial T2* as the primary
`outcome measure to determine whether deferiprone had superior
`cardiac efficacy compared with deferoxamine.
`
`Patients, materials, and methods
`
`Patient recruitment
`
`This open-label trial was conducted in 4 centers in Italy and Greece. All
`patients had homozygous beta-thalassemia major, were regularly transfu sed
`
`From the National Heart and Lung Institute, Imperial College, London, United
`Kingdom; Royal Brompton Hospital, London, United Kingdom; Aghia Sophia
`Children's Hospital, Athens. Greece: Aghia Sophia Children's Hospital,
`University of Athens, Athens, Greece: Centro Microcitemie, University of
`Torino, Torino, Italy; Laikon Hospital, University of Athens, Athens, Greece;
`Institute Euromedica-Encephalos. Athens. Greece; Whittington Hospital,
`London, United Kingdom: and Ospedale Regionale per le Microcitemie,
`Cagliari, Italy.
`
`Several of the authors (D.J.P. , V.B., A.P .. E.D.G., A.G.) have declared a
`financial interest in Apotex, whose product, deferiprone, was studied in the
`present work. Several of the authors (D.J.P .. A.P., R.G.) have declared a
`financial interest in Nov~rtis, whose product, deferoxamine, was studied in the
`present work.
`
`Reprints: Dudley Pennell, Professor of Cardiology, Royal Brampton Hospital,
`Sydney Street, London SW3 SNP, United Kingdom; e-mail: d.pennell@ic.ac.uk.
`
`Submitted July 22, 2005; accepted December 1, 2005. Prepublished online as
`Blood First Edition Paper, December 13, 2005; DOI 10.1182/blood-
`2005-07-2948.
`
`The publication costs of this article were defrayed in part by page charge
`payment. Therefore, and solely to indicate this fact, this article is hereby
`marked "advertisement" in accordance with 18 U.S.C. section 1734.
`
`Supported by Apotex Research Inc.
`
`© 2006 by The American Society of Hematology
`
`3738
`
`~--
`
`BLOOD, 1MAY2006 · VOLUME 107, NUMBER 9
`
`1 of 8
`
`Taro Pharmaceuticals, Ltd.
`Exhibit 1057
`
`

`

`From www.bloodjournal.org by guest on June 4, 2018. For personal use only.
`
`BLOOD, 1MAY2006 ·VOLUME 107, NUMBER 9
`
`HEART CHELATION RCT
`
`3739
`
`and chelated with subcutaneous deferoxamine monotherapy, and had no
`symptoms of heart failure prior to screening. The mean dose of deferox(cid:173)
`amine in the randomized patients prior to entry into the trial was 39 :!: 8
`mg/kg/d for 5.7 d/wk (equivalent to 32 mg/kg/d). Patients aged 18 years or
`older were screened (n = 160) and selected if the myocardial T2* was
`abnormal(< 20 ms) but not severe (< 8 ms) and if the LY EF was greater
`than 56%. No patient with symptomatic heart failure was eligible for the
`trial. This rationale excluded patients with no significant cardiac siderosis
`and allowed patients with severe myocardial siderosis or LY dysfunction to
`receive the best current clinical management. Sixty-one patients were
`randomized (Figure I). The reasons for screening failure (n = 99) were
`usually a myocardial T2* outside the required range ( < 8 ms in 11 % ; > 20
`ms in 76%) . Additional less common exclusions were LY EF Jess than 56%
`(2%); li ver enzymes greater than 3 limes upper limit (3%); unsuitable
`psychological condition (I%); age younger than 18 or older than 36 years
`(8%); claustrophobia (3%); pretransfusion hemoglobin (Hb) level Jess than
`90 g/L (9 g/dL; 3%); refused or unable to participate (7%). Eighteen
`patients failed more than one criterion. Each center's ethics committee
`approved the study and patients gave signed informed consent. Secondary
`trial end points included cardiac volumes and function , liver iron concentra(cid:173)
`tion (LIC), and serum fcrritin concentrations.
`
`Cardiovascular magnetic resonance
`
`The T2* sequence was installed in Athens (GE CYi: GE Healthcare,
`Slough. United Kingdom) and Cagliari (GE Signa. Echo-speed; GE
`Healthcare). Validation at each site included scanning of phantoms of
`known T2* value, the scanning of 5 patients at each site twice for local
`reproducibility, and rescanning within 3 days after flying to London for
`comparison with a reference scanner (Siemens Sonata; Siemens, Erlangen,
`Germany). We predefined a limit of acceptabi li ty of 15% variation in T2*
`for each site compared with London. The variability compared with London
`was 9.7% in Athens and 1.6% in Cagliari. Site interstudy variability was
`3.5% and 2.4%, respectively. These results 15 and full details of the T2* MR
`sequence have been published.13 Myocardial T2* was analyzed using
`dedicated software (Thalassemia-Tools; Cardiovascular Imaging Solutions,
`London, Unjted Kingdom) with consistent regions of interest in the
`ventricular septum which avoid susceptibility artefacts,s.22 as previously
`described. 13·14 Cardiac volumes were acquired using contiguous steady(cid:173)
`state free-precession short-axis cines from base to apex,2J a technique with
`excellent reproducibility. 24 Measurements were scheduled for 3 to IO days
`after transfusions. A core laboratory in London analyzed all CM R scans
`using dedicated software (CMRtools; \:<fdiovascular Imaging Solutions).
`All measurements were made in Londop by 2 reviewers in consensus who
`were blinded to treatment allocation. Trial analyses were not fed back to the
`centers during the trial.
`
`Other iron measurements
`
`UC was assessed at baseline and 12 months using a superconducting
`quantum interference device (SQUID).25 All the measurements were
`centralized at the Turin University facility (Model 5700 3-Channel SQUID;
`Tristan Technologies, San Diego. CA).26 Prior to the start of the trial.
`SQUID was considered the best noninvasive technique for measuring liver
`iron level. Serum ferritin concentration was measured at baseline and every
`3 months. Serum was separated, labeled. and stored frozen at -20°C until
`
`Figure 1. Screening, randomization, completion, and withdrawal patient num(cid:173)
`bers.
`
`being shipped to a central laboratory. where it was measured by micropar(cid:173)
`ticle enzyme immunoassay (AXSYM System: Abbou Diagnostics, Abboll
`Park, IL).
`
`Safety assessments
`
`Patients were monitored weekly for absolute neutrophil count (ANC) and
`any adverse events. Serum alanine transaminase (ALT) levels were
`measured quarterly. serum zinc levels were measured at baseline and every
`6 months, and serum creatinine levels were measured at baseline and
`12 months.
`
`Statistical analysis
`
`The statistical analysis plan was defined prior to breaking the randomization
`code and locking of the database of the study. All continuous parameters
`were analyzed using the 2-sample t test. using a P value of .05 as the
`threshold for statistical significance. Since tissue iron is linearly related to
`the inverse of T2*, trus measure was log transformed prior to analysis to
`linearize the relationship and provide an unbiased estimate of relative
`change from baseline for both treatm~nts. Data are presented as mean plus
`or minus standard deviation (SD). except for the T2* data, which used the
`geometric mean (antilog of the mean of the log data) plus or minus the
`I], where MSE is the
`coefficient of variation (CV), defined as y[eMSE -
`mean square error (equivalent to the variance of the mean in log scale).
`Proportions of patients between the treatment groups were compared by the
`Fisher exact test. Trend analysis over time for ferritin and ALT data were
`performed using repeated-measure analysis of variance (ANOYA: MIXED
`in SAS, SAS Institute, Cary. NC). Sample size calculations indicated that in
`the single-center setting. 32 patients would show a 5% difference in
`myocardial T2* between drugs for a type I error of 0.05 and a power of
`80%. This sample size was increased to 60 to allow for reproducibility
`deterioration in the multicenter setting and to allow for 20% dropouts. All
`analyses presented are based on intemion to treat. Last observation carried
`forward was used to fill in the missing data for withdrawn patients in the
`efficacy analyses. Deferiprone compliance was measured using the Medica(cid:173)
`tion Event Monitoring System device (Aardex, Zug, Switzerland) and
`calculated as the percent of openings with an interval longer than 4 hours
`recorded, divided by number of doses prescribed. Deferoxamine compli(cid:173)
`ance was calculated as the percentage of completed infusions. as deter(cid:173)
`mined by the Crono pumps, divided by the number of infusions prescribed.
`Statistical analysis was performed using SAS Institute (for PC, release 8.2).
`
`Results
`
`Patient characterization
`
`The baseline characteristics are shown in Table 1. The groups were
`well matched for the primary end point of myocardial si derosis.
`Matching was good for most other measures includi ng liver iron
`level and transfusional iron input, but significant differences were
`present for the serum ferritin level , hemoglobin level, and white
`cell count.
`The target dose for subcutaneous deferoxamine was 50 mg/kg/d
`for at least 5 days _per week. The actual dose prescribed for
`deferoxamine was 43 mg/kg for 5.7 d/wk (equivalent to 35 mg/kg/d
`for 7 days per week). This is equal to the recommended dose of 35
`mg/kg/d for stable patients with si milar ferritin levels from the
`product data sheet and slightly higher than the 40 mg/kg/d for 5
`dlwk from clinical recommendations,27 though lower than the
`maximal dose sometimes used in clinical practice. Oral deferiprone
`was initiated at 75 mg/kg/d and increased to the target of 100
`mg/kg/d. The actual prescribed dose of deferiprone was 92
`mg/kg/d. Compliance was similar (deferiprone 94% :t 5.3%; defer(cid:173)
`oxamine 93% :t 9.7 %; P = .81 ). Five patients withdrew, 3 taking
`deferoxamine ( 1, deterioration of cardiac function; 2, personal
`
`2 of 8
`
`Taro Pharmaceuticals, Ltd.
`Exhibit 1057
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`

`

`From www.bloodjournal.org by guest on June 4, 2018. For personal use only.
`
`3740
`
`PENNELL et al
`
`BLOOD, 1 MAY2006 · VOLUME 107, NUMBER 9
`
`Table 1. Descriptive statistics of the treatment groups at baseline
`
`No. randomized(%)
`Age, y
`Sex, no. (%)
`Male
`Female
`Ethnicity, no. (%)
`Greek
`Italian
`Race, no. (%)
`White
`Heart measures
`Myocardial T2•, ms (CV%)
`End-diastolic volume, ml
`End-systolic volume, ml
`Ejection fraction, %
`Iron measures
`liver iron concentration, µg/l
`Serum ferritin level, µg/l
`No. with serum ferritin levels above 2500 µg/l (%)
`Blood measures
`Transfusional iron input, ml/kg/year
`Hemoglobin level, g/l
`Total white blood cell count, x 109/l
`Corrected white blood cell count, x 109/l
`Absolute neutrophil count, x 109/l
`Platelet count, x 109/l
`Liver measure
`Alanine transaminase, U/l
`Hepatitis C-positive, no.(%)
`Yes
`No
`HIV-positive, no.(%)
`Yes
`No
`Splenectomy, n o. (%)
`Yes
`No
`Other biochemistry
`C reatinine level. µM
`Zinc level, µM
`Weight, kg
`
`, I
`
`Defer iprone
`
`29 (48)
`25.1 ;!; 3.8
`
`15 (52)
`14 (48)
`
`16 (55)
`13 (45)
`
`29 (100)
`
`13.0(32)
`134 ;!; 32
`43 :!: 14
`69.7 ;!; 5.4
`
`6.16 :!: 6.0
`1791 ;!; 1029
`5 (17)
`
`152 :!: 43.4
`105 • 12.0
`
`7.86 :!: 3.39
`7.68 :!: 2.96
`4.26 :!: 1.62
`318 :!: 129
`
`37.7 :!: 32.1
`
`18 (62)
`11 (38)
`
`0 (0)
`29 (100)
`
`4 (14)
`25 (86)
`
`7 1.0 :!. 12.5
`13.0 :!: 3.6
`57.7 ::!: 7.9
`
`Deferoxam in e
`
`32 (52)
`26.2 :!: 4 .7
`
`16 (50)
`16 (50)
`
`18 (56)
`14 (44)
`
`32 (100)
`
`13.3 (30)
`132 :!: 23
`41:!:13
`68.4 ;!; 4.9
`
`6.32 :!: 5.8
`2795 ;!; 2441
`13 (41)
`
`144 .. 44.4
`113 • 11 .9
`11.5 :!: 9.42
`9.79 ;!; 4.49
`5.10 :!: 2.28
`318 ;!; 159
`
`52.2 :!: 33.8
`
`16 (50)
`16 (50)
`
`0 (0)
`32 (100)
`
`11 (34)
`21 (66)
`
`69.1.!: 12.8
`13.3 :!: 2.3
`60.6 ::!: 13.2
`
`p
`
`NA
`.33
`.99
`
`.99
`
`.99
`
`.77
`.81
`.51
`.34
`
`.92
`.039
`.055
`
`.52
`.023
`.047
`.033
`.11
`.99
`
`.093
`.44
`
`NA
`
`.079
`
`.56
`.78
`.30
`
`Data are shown as number(%) or mean :!: SD, except for the myocardial T2". which is shown as geometric mean and coefficient of variation (CV).
`NA indicates not applicable.
`
`reasons) and 2 taking deferiprone (elevated li ver enzymes, which in
`I case was probably caused by cytomegalovirus hepatitis with
`increased lgM levels to CMY that fell but with negative polymer(cid:173)
`ase chain reaction [PCR)).
`
`Myocardial T2•
`
`Myocardial TI* rose with deferiprone at 6 and 12 months co 15.4
`ms (+18%; CV 38%; P< .00 1) and 16.5 ms (-'-27%; CY 38%;
`P < .00 I). The myocardial TI* rose with deferoxamine at 6 and 12
`monchs to 14.4 ms (+9%; CY 37%; P = .003) and 15.0 ms
`( + 13%; CY 39%; P < .00 1). The difference in the change between
`drugs was significant at 6 months (ratio of geometric mean, 1.09;
`P = .040) and at 12 months (ratio, 1.12; P = .023; Figure 2). A rise
`in TI* and EF was seen in 19 (66%) deferiprone-treated patients
`and 14 (45%) deferoxamine-treated patients.
`Because of the baseline di fferences between groups in serum
`ferritin level, white cell count, and hemoglobin level, further
`analysis of these factors and their interaction with the outcome of
`the primary end point was perfonned. The predefined statistical
`
`plan called for parametric analysis of the serum ferritin level, but
`o n inspection of the data, we found 2 extreme outliers in the
`dcferoxamine-treated group with fcrritin values of 9259 and 9300
`µg/L, and the Shapiro-Wilk test indicated that the group was not
`normally distributed (P < .00 1). Accordingly, a log transformation
`was applied and this was successfu l in nonnalizing the ferritin data
`(P = .76). In addition, the differences in white cell count and
`hemoglobi n level were examined, as both were significamly higher
`in the deferoxamin~·treated group. These di fferences appear to
`have resulted from the difference in the number of splcnectomizcd
`patients in the 2 therapy arms (34% in the deferoxamine-trcated
`group vs 14% in the deferiprone-treated group). The splenecto·
`mized patients had significantly higher corrected white cell counts
`than nonsplenectomized patients (P < .00 I ). Data review showed
`4 splenectomized patients in the deferoxamine-treated group had
`baseline corrected white cell counts greater than 20 X I 09/L. The
`larger number of splenectomized patients in the deferoxamine(cid:173)
`treated group could also explain the higher hemoglobin level in the
`deferoxamine-treated group because of decreased red blood cell
`
`3 of 8
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`

`From www.bloodjournal.org by guest on June 4 , 2018. For personal use only.
`
`BLOOD, 1 MAY 2006 · VOLUME 107, NUMBER 9
`
`HEART CHELATION RCT
`
`3741
`
`(RBC) consumption to maintain the same hemoglobin level despite
`similar mean transfusional input between the 2 groups ( 151.6 :!: 43.4
`mUkg/y in the deferiprone-treated group vs 144.3 :!: 44.4 ml.Jkg/y
`in the defcroxamine-treated group; P = .52). Therefore, we con(cid:173)
`ducted a multivariate analysis o f the effect on the myocardial T2*
`of baseline differences in log serum ferritin level and splenectomy
`status. This showed that the baseline ferritin level does not have a
`significant impact on the improvement in T2* (P = .66), but
`splenectomy was significantly predictive (P = .002). Thus splenec(cid:173)
`tomized patients exhibited greater T2* improvement than nonsple(cid:173)
`nectomized patients. The anti log of the esti mated effect size
`1sso = 1.20), which is equal to the ratio of geometric mean
`(e0
`-
`between splenectomized and nonsplenectomized patients, ind icates
`that the splenectomized patients were 20% better in improving T2*
`than nonsplenectomized patients. After controlling for the basel ine
`ferri tin values and the splcnectomy status, the difference in T2*
`favoring deferiprone remained significant and its significance was
`substantially greater (P = .002). Since the deferoxamine-treated
`group had more splenectomized patients than the deferipronc(cid:173)
`treated group, an even greater difference in mean change from
`baseline in T2* in favor of deferiprone would have been expected
`had there been an equal number of spl enectomized patients in the 2
`treatment groups.
`
`Cardiac function and volumes
`
`At 12 months, there was a significant difference favoring de(cid:173)
`feriprone for reduction in end-systolic volume (-6.4 :!: 6.8 mL vs
`- 0.6 :!: 7.9 mL; P = .004) and a borderline difference in reduction
`of end-di astolic volume (-7.8 :!: 13 mL vs -1.2 :!: 13 mL;
`P = .060). The EF rose with deferiprone by absolute units of
`
`2.0% :!: 2.7% at 6 months ( P < .001) and 3.1% = 3.6% at 12
`(P < .001). The EF rose with deferoxamine by
`months
`0.52% :!: 3.5% at 6 months (P = .42) and 0.32% :!: 3.4% at 12
`months (P = .66). The difference in the change between gro ups
`was borderline at 6 months (P = .074) and significant at I 2 months
`(P = .003; Figure 3). The percent change in T2* and EF with
`deferiprone was significantly correlated (r2 = 0.21; P = .012),
`although this was relative ly weak an~ not useful to predict the EF
`change from the change. in T2*. T\;Clfe was no correlation with
`deferoxamine (r2 = 0.036; P = .49).
`
`18
`
`17
`
`- - n creriprone
`·-<:>· Derero~~mlne
`................... . .
`
`] 15
`1:
`" " f:. I~
`... .e.
`
`13
`
`12
`
`B~selinc
`
`- - ,
`6 months
`12 months
`Figure 2. The change in myocardial T2• at 6 and 12 months was significantly
`greater in the patients taking deferiprone rather than deferoxamine. In lhis
`analysis, 29 deferiprone-treated patients and 31 deferoxamine-treated patients are
`included ( 1 deferoxamine-treated patient was excluded because T2" and ejection
`fraction were not measured at 6 and 12 months, and the 4 dropouts were included
`using last observation carried over). The vertical axis shows the geometric mean of
`T2". Standard error bars are shown.
`
`~
`
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`
`6 months
`
`12 months
`Figure 3. The change in left ventricular (LV) ejection fraction at 12 months was
`significantly greater in the patients taking deferiprone rather than deferox(cid:173)
`amine. In lhis analysis, 29 deferiprone-treated patients and 31 deferoxamine·treated
`patients are included (1 deferoxamine·treated patient was excluded because r2· and
`ejection fraction were not measured at 6 and 12 months, and the 4 dropouts were
`included using last observation earned over). Standard error bars are shown.
`
`Other iron measures
`
`One patient in the deferiprone-treated group did not have an UC at
`basel ine and there were 3 patients (I defcriprone and 2 deferox(cid:173)
`amine) who did not have an LIC val ue at 12 months. The last
`observation carried over technique could not be used for those 3
`patients and they were excluded from the analysis at I 2 months.
`Therefore, LIC was assessed in 27 and 30 patients for the
`deferiprone- and deferoxamine-treated groups, respectively. LIC
`fell with deferiprone by 0.93 :!: 2.9 mg/g dry weight at I 2 months
`(-I 0. I%; P = .11) compared with a fall with deferoxamine by
`1.54 :!: 2.5 mg/g dw at 12 months (-24.4%; P = .002). The
`difference between groups at I 2 months was not significant
`(P = .40). The change in ferrilin level at 6 months with deferiprone
`and deferoxamine was 151 :!: 7 13 µg/L and -314 :!: 921 µg/L
`(P = .033 between groups) and at I 2 months - 18 I ± 826 µg/L
`and -466 ± 739 µg/L (-
`l 0.1 % and - I 6. 7% change from base(cid:173)
`line values, respectively; P = . I 6 between groups). There was no
`difference in trend of serum fe rritin level over time between groups
`(P = .4 1).
`
`Vital signs
`
`Weight gai n was greater with deferiprone at 6 months ( 1.6 :!: I .8 kg
`vs -0.22 :!: 2.7 kg; P = .004) and at 12 months (2.2 :!: 3.0 kg vs
`0.1 :!: 2.7 kg; P = .004). There were no significant differences
`between groups in other vital signs.
`
`Other laboratory measures
`
`The difference between the deferiprone- and deferoxamine-treated
`groups in change of ALT level at 12 monihs was not significant
`(22.9 :!: 48.6 U/L vs 4.7 :!: 38.2 U/L; P = . I I). This includes the 2
`patients who dropped o'ut for increased serum enzyme levels. There
`was no significant difference in trend of ALT level o ver time
`between groups (P = .32). The difference in percentage of patients
`wi th ALT greater than twice the upper limit was not significant at
`baseline or at 12 months.
`There was no significant difference between groups in the
`change of zinc level at I 2 months (-0.80 :!: 2.8 µM vs 0.23 :!: 2.3
`µM; P = . I 2). There was no significant difference between groups
`in the change in creatinine level at 12 months (3.24 :::: 10.5 µM vs
`0.06 :!: I 2.7 µM; P = .29). There were no signifi cant differences
`between groups in other laboratory data, including ANC.
`
`4 of 8
`
`Taro Pharmaceuticals, Ltd.
`Exhibit 1057
`
`

`

`From www.bloodjournal.org by guest on June 4, 2018. For personal use only.
`
`3742
`
`PENNELLetal
`
`Adverse events
`
`The most frequent adverse events with deferiprone were gastroin(cid:173)
`testinal symptoms (nausea, vomiting, or abdominal pain), which
`occurred in 19 (66%) patients. These usually occurred in the first
`weeks of treatment, were mild to moderate, and usually resolved
`within a median of 3 days (range, 1-17 days) without discontinua(cid:173)
`tion or decreasing the dose of deferiprone. Deferoxamine adverse
`events included reactions at the infusion site, which occurred in 12
`(38%) patients. Joint problems, including pain and/or swelling,
`occurred in 8 (28%) deferiprone-treated patients and in 6 (19%)
`deferoxamine-treated patients (P = .30). Nine (31 %) deferiprone(cid:173)
`treated patients reported increased appetite (P < .001 ). One epi(cid:173)
`sode of neutropenia (I.O J X 109 neutrophils/L) occurred in one
`deferiprone-treated patient. The event resolved within 3 days
`(2.69 X 109 neutrophils/L) without discontinuation or decreasing
`the dose of deferiprone. There were no episodes of agranulocytosis.
`
`Discussion
`
`Heart disease, which results from myocardial iron deposition
`associated with lifelong blood transfusions and increased gut iron
`uptake, is the most common cause of death in beta-thalassemia
`major. Recently, it has become possible to target therapy for
`myocardial siderosis using myocardial T2*, allowing comparison
`of the myocardial efficacy of iron chelators. Usi ng myocardial T2*,
`continuous intravenous deferoxamine has been shown to reduce
`myocardial siderosis in acute heart failure, 11 although iron clear(cid:173)
`ance was considerably slower from heart than liver. In the current
`trial , all screened patients had no cardiac symptoms and were
`receiving chronic deferoxamine monotherapy, and those who were
`subsequently randomized either continued deferoxamine at an
`increased dose ( +4 mg/kg/d; P = .00 I) followi ng entry into the
`trial with standardization of treatment or were switched to de(cid:173)
`feriprone monotherapy. We found a significant reduction in our
`primary trial end point of myocardial siderosis in the deferoxamine(cid:173)
`treated group (T2* increased by 13% at 12 months; P < .001),
`which probably resulted from the i~creased dose of deferoxamine
`and/or improved compliance. D~spite this improvement in the
`control group, the deferiprone-treated group showed superior
`efficacy in reducing myocardial siderosis (T2* increased by 27% at
`12 months, P < .00 I; P = .023 vs deferoxamine-treated group at
`12 months). These data accord with a previous retrospective study
`showing lower myocardial iron with deferiprone.21 Although the
`clinical efficacy of raising myocardial T2* for asymptomatic
`patients remains to be determined, it would appear that reduced
`levels of myocardial iron are a favorable response.
`The deferiprone-treated group also exhibited significant improve(cid:173)
`ment in secondary trial end points compared with deferoxamine,
`with a reduced end-systolic volume and increased EF. In this trial,
`we excluded patients with an EF less than 56% by CMR, which is
`the lower limit for healthy nonanemic subjects.28 We believed this
`was sufficient evidence that significant LY systolic dysfunction was
`present and that the best current medical treatment should be
`offered outside the trial setting. However, "nonnal" cardiac vol(cid:173)
`umes and function in thalassemia are not well defi ned. Compared
`with healthy nonanemic subjects, thalassemia patients" hearts have
`larger end-diastolic volumes and increased cardiac output,7.29.30
`which allows for increased perfusion for tissue oxygenation
`requirements. In addition, the ejection fraction in thalassemia
`major patients with no iron loading (T2* > 20 ms) is higher than in
`
`BLOOD, 1MAY2006 · VOLUME 107, NUMBER 9
`
`controls with a lower limit of up to 63%.s.7.30 Thus, because the EF
`in thalassemia without myocardial siderosis is higher than in
`heal thy nonanemic individuals, we believe that our trial included
`patients with subclinical LY dysfunction. The increase in EF seen
`in this trial accords with this view and suggests that deferiprone
`was effective in relieving this dysfunction. Reduced EF is linked
`with adverse survival not only in thalassemia31 but also in coronary
`artery disease32 and heart fai lure,33 and improved prognosis occurs
`with treatments that improve EF.34·35 Deferiprone also reduced
`end-systolic volume, another prognostic parameter in large36 and
`normal-sized hearts.37 Heart fail ure treatments known to improve
`prognosis reduce the end-systolic volume,38 although this has not
`been shown directly in thalassemia patients. These prospective
`randomized data are also consistent with a previous srndy showing
`significantly superior EF with deferiprone.21
`It therefore appears that deferiprone could reduce the risk of
`progression to iron-related cardiomyopathy by removing more
`cardiac iron than subcutaneous deferoxamine, and the LY function
`and volume improvements in patients with subclinical LY dysfunc(cid:173)
`tion could yield prognostic benefit. Lower levels of myocardial
`siderosis would allow an increased reserve fo r any future periods of
`iron loading and the potential for greater resistance to catastrophic
`heart failure that can be seen in thalassemia patients with intercur(cid:173)
`rent infection. These interpretations accord with longitudinal
`srndies of EF in thalassemia31 and previous retrospective survival
`data using deferiprone or deferoxamine.39 With more than 4 years
`of follow-up, cardiac dysfunction was newly diagnosed in 4% of
`the deferiprone-treated patients and 20% of the deferoxamine(cid:173)
`treated patients (P = .007). This was accompanied by no deaths
`with deferiprone but 3 cardiac-related deaths with deferoxamine.
`These findings suggest differences in the in vivo myocardial
`efficacy of these drugs. Deferoxami ne is an important chelator042
`but is a large positively charged molecule, relatively lipophobic,
`and one that undergoes conformation change on binding of iron,
`which may lead to intracellular trapping.43 These properties
`potentially limit its ability to chelate intracellular iron, unless there
`is an active excretion pathway, as postulated for deferoxamine in
`hepatocytes.43·44 By contrast, deferiprone is a small, neutral mole(cid:173)
`cule with greater lipophilicity and therefore has significantly
`greater potential to chelate intracellular iron .45.46 This suggests that
`dcferiprone may have preferential access to intracellular iron in
`tissues such as the myocardium, and in vitro and animal data
`support this hypothesis.47 Because of these variations in action,
`combination therapy with these chelators, for which there is
`supportive in vitro47 and clinical evidence,48 may be attractive.
`Combination therapy is being subjected to a further randomized
`controlled trial for cardiac efficacy.49
`Three previous randomized trials have compared the myocar(cid:173)
`dial effects of chelators. Maggio et al50 compared deferiprone (75
`mg/kg/d) with deferoxami ne (50 mg/kg/d for 5 d/wk). No differ(cid:173)
`ence was found between groups in serum ferritin level or T2-
`weighted myocardi~I signal intensity ratio (SIR). Peng et aJ51
`compared deferiprone (75 mg/kg/d) with deferoxamine (50 mg/
`kg/d for 2: 5 d/wk). Deferiprone resulted in a significantly larger
`improvement in SIR and EF. Galia et a152 compared deferiprone (75
`mg/kg/d) with deferoxamine (50 mg/kg/d for 6 d/wk). No signifi(cid:173)
`cant differences between groups were demonstrated in myocardial
`SIR or EF. Our current trial differs from these reports in several
`ways that might