Mycophenolate mofetil 500-mg tablet under fasting conditions: Single-dose, randomized-sequence, open-label, four-way replicate crossover, bioequivalence study in healthy subjects

Clinical Therapeutics/Volume 32, Number 3, 2010

556 Volume 32 Number 3

Accepted for publication October 29, 2009.doi: 10.1016/j.clinthera.2010.03.0080149-2918/$ - see front matter

© 2010 Excerpta Medica Inc. All rights reserved.

AbsTrACTBackground: Mycophenolate mofetil (MMF), a pro-

drug of mycophenolic acid (MPA), is an immunosuppres-sive agent indicated for the prophylaxis of organ rejection in allogeneic kidney, heart, or liver transplant recipients. The European regulatory authorities require bioequiva-lence studies for the marketing of generic products.

Objective: The aim of this study was to assess the bioequivalence of a generic (test) and branded (refer-ence) formulation of MMF 500 mg and MPA.

Methods: This single-center, single-dose, randomized, open-label, 4-way crossover study was conducted at Anapharm’s Clinical Research Facility, Québec, Québec, Canada. Healthy volunteers aged 18 to 55 years were eligible. Subjects were assigned to receive, in random-ized order, a single dose of the test and reference for-mulations of MMF 500 mg under fasting conditions. Because the study design was 4-way replicate, there were 2 test periods and 2 reference periods. The 4 study periods were each separated by a 14-day washout period. Blood samples were collected over a period of 12 hours after administration for the deter-mination of MMF pharmacokinetic properties, and over 48 (±0.5) hours, for MPA properties. Con-centrations of the analytes were determined by reverse LC and detected using LC-MS/MS. Pharmacokinetic parameters were calculated from MMF and MPA concentration data using noncompartmental analysis. Cmax and AUC0–t were the primary evaluation criteria, while AUC0–∞ was a secondary parameter. The drugs were to be considered bioequivalent if the 90% CIs for the test/reference ratios of natural logarithm–transformed values of these parameters (obtained using

ANOVA) were between 80% and 125%, per European regulations for bioequivalence. Tolerability was moni-tored using physical examination, including vital sign measurements, laboratory analysis, and adverse-events (AE) monitoring (including patient interview).

Results: A total of 103 subjects were enrolled (64 men, 39 women; 101 white, 2 black; mean [SD] age, 38 [10] years; weight, 68.2 [9.1] kg). The 90% CIs were as follows: MMF, Cmax, 85.94% to 106.63%; AUC0–t, 91.94% to 102.20%; and AUC0–∞, 93.15% to 105.48%; MPA, Cmax, 92.03% to 105.82%; AUC0–t, 97.42% to 100.59%; and AUC0–∞, 96.96% to 100.90%. These values met with the regulatory definition of bioequivalence. A total of 148 AEs were reported (68 in subjects who received the test treat-ment and 80 in subjects who received the reference treatment). The most commonly reported AEs were procedural pain (13/102 [12.7%] and 10/101 [9.9%] with the test and reference formulations, respectively), procedural site reaction (12 [11.8%] and 4 [4.0%]), and somnolence (7 [6.9%] and 14 [13.9%]).

Conclusions: The generic and branded formula-tions of MMF 500 mg met the European regulatory criteria for assuming bioequivalence, based on the rate and extent of absorption of a single dose under fasting conditions. Both formulations were well tolerated in these healthy volunteers. (Clin Ther. 2010;32:556–574) © 2010 Excerpta Medica Inc.

Mycophenolate Mofetil 500-mg Tablet Under Fasting Conditions: Single-Dose, Randomized-Sequence, Open-Label, Four-Way Replicate Crossover, Bioequivalence Study in Healthy Subjects

Susana Almeida, MSc1,2; Augusto Filipe, MSc1; Rita Neves, MSc1; Ana Cristina Franco Spínola, MSc1; Mario Tanguay3; Jordi Ortuño4; Anna Farré, MSc4; and Alex Torns4

1Medical Department, Grupo Tecnimede, Sociedade Tecnico-Medicinal S.A., Sintra, Portugal; 2Department of Pharmacology and Therapeutics, Universidad Autònoma de Barcelona, Barcelona, Spain; 3Anapharm, Montreal, Québec, Canada; and 4Anapharm Europe S.L., Barcelona, Spain

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terohepatic recirculation, secondary increases in plas-ma MPA concentrations might be observed at ~4 to 12 hours after the administration of MMF.3 A negli-gible amount of the initial dose is excreted as MPA in the urine.1 The mean apparent t1/2 of MPA ranges between 11 and 19 hours.2 The European regulatory criteria require testing for bioequivalence of generic and branded formulations for the marketing approval of generic formulations.

The present study aimed to assess the bioequivalence of a generic (test) and a branded (reference) formula-tion of MMF 500 mg and its active metabolite.

sUbJECTs AND METhoDsstudy Protocol

An independent ethics committee (Institutional Review Board Services, Aurora, Ontario, Canada) approved the clinical study protocol, and a letter of no objection was obtained from Canadian authorities. This single-center, single-dose, randomized, open-label, 4-way crossover study was conducted in accor-dance with the Declaration of Helsinki4 and the Guideline for Good Clinical Practice,5 and written informed consent was obtained from each participant before study commencement. The clinical part of the study was conducted at Anapharm’s Clinical Research Facility (Québec, Québec, Canada) and the bioana-lytic part at Anapharm Europe S.L. facility (Barcelona, Spain).

subjectsHealthy volunteers were recruited from the com-

munities of Québec, Montréal, and Trois-Rivières, Canada. Men and women aged 18 to 55 years with a body mass index (BMI) between 20 and 27 kg/m2

were eligible.Volunteers who smoked >9 cigarettes per day, were

unable to provide consent, had illness or surgery within 4 weeks before administration of the study medication; had abnormal findings on ECG or vital sign measurement, or laboratory testing for hepatitis B or C or HIV at screening; had a history of signifi-cant use of alcohol or drugs within 1 year before the screening visit; had a history of an allergic reaction to food or drugs or used drugs known to induce or in-hibit hepatic drug metabolism within 14 days before administration of the study medication; or had used a prescription or over-the-counter medication within 7 days before administration of the study medication

Key words: AUC, bioequivalence, Cmax, pharmaco-kinetic, mycophenolate mofetil, mycophenolic acid, MMF, MPA.

INTroDUCTIoNMycophenolate mofetil (MMF) is an immunosuppres-sant indicated for the prophylaxis of organ rejection in allogeneic kidney, heart, or liver transplant recipi-ents. The recommended dosage ranges between 1 and 1.5 g BID (total daily dose, 2–3 g).1 Plasma drug con-centrations may be monitored as deemed appropriate for the purpose of dose adjustments.

The active metabolite of MMF, mycophenolic acid (MPA), is a potent, selective, uncompetitive and re-versible inhibitor of inosine monophosphate dehydro-genase. MPA inhibits the de novo pathway of guano-sine nucleotide synthesis without incorporation into DNA. Because T- and B-lymphocytes are critically de-pendent for their proliferation on de novo synthesis of purines, whereas other cell types can use salvage path-ways, MPA has more potent cytostatic effects on lym-phocytes than on other cells.1

Following oral administration, MMF is absorbed and undergoes presystemic metabolism to the active metabolite, MPA. As evidenced by suppression of acute rejection following renal transplantation, the immunosuppressant activity of MMF is correlated with MPA concentration. The mean absolute bioavailabili-ty of oral MMF (expressed in terms of MPA exposure) is 94%.1 As per the product information,1 MMF is not measurable systemically in plasma following oral administration. However, the development of more sensitive bioanalytic assay allows the detection of par-ent compound in plasma, even though the concentra-tions are <1% that of MPA. MPA is highly bound to plasma albumin (97%).1 When MMF was orally admin-istered to healthy volunteers, Tmax was ~0.5 to 2 hours.2

Although the systemic exposure of MPA is not signifi-cantly different when MMF is administered with or without food,1 peak concentrations are decreased by ~40% when administered with food.1

MPA is metabolized in the liver to form the phe-nolic glucuronide of MPA (MPAG), which is not phar-macologically active. MPAG is highly (82%) protein bound and is excreted in the urine. During renal dys-function, MPAG concentrations increase and compete with MPA for protein binding. This fact allows for higher blood MPA concentrations.3 As a result of en-


Clinical Therapeutics

(macroscopic examination, pH, specific gravity, protein, glucose, ketones, bilirubin, occult blood and cells, nitrite, urobilinogen, and leukocytes), and mi-croscopic examination (performed on abnormal find-ings). For serum and urinary pregnancy testing, Gamma-Dynacare Medical Laboratories (Québec, Québec, Canada) was used as the clinical laboratory facility. The remaining diagnostic tests were conducted at Anapharm Clinical Laboratory (Québec, Québec, Canada). Both clinical laboratories are certified for internal and external quality control by independent organizations (College of American Pathologists, Northfield, Illinois; Société québécoise de biologie Clinique, Québec, Québec, Canada; and Laboratoire de santé publique, Québec, Québec, Canada).

Seated blood pressure (BP) and heart rate were measured before study drug administration and ~24 and 48 hours after administration in each study pe-riod. Vital sign measurements were repeated at least once as soon as possible after the initial scheduled measurement under the following conditions: systol-ic BP (SBP) <90 or >140 mm Hg, diastolic BP (DBP) <50 or >90 mm Hg, and/or heart rate <50 or >100 beats/min.

study Drug AdministrationSubjects were enrolled by the qualified investigator

or the medical subinvestigator. On arrival at the clini-cal facility for the first study period, subjects were assigned numbers that corresponded to a randomiza-tion code generated by Anapharm (Canada) using SAS version 8.2 (SAS Institute Inc., Cary, North Carolina). The computer-generated sequence ensured equal dis-tribution of treatments at multiples of 4, the block size, from the list of subjects’ assignments, after ran-dom definition of the starting value. The randomiza-tion scheme was unavailable to the Bioanalytical Divi-sion of Anapharm Europe S.L. until completion of the clinical and analytic phases. The scheme was separat-ed into 3 groups by the clinical staff to account for technical restrictions. The study design was a 4-way replicate (2 test and 2 reference periods). The investi-gator and clinical staff were blinded to treatment as-signment until after subjects qualified as eligible for the study. The pharmacist was unblinded to the ran-domization scheme but had no role in the conduct of the study.

After a supervised overnight fast of ≥10 hours, at 6 am and 7:10 am, subjects were administered, per the

were excluded. Volunteers were also excluded if they had a history of gastrointestinal abnormalities or un-resolved symptoms; liver or kidney disease; neurologic, cardiovascular, pulmonary, hematologic, immuno-logic, psychiatric, or endocrine/metabolic disease; an activated renin-angiotensin system; a history or pres-ence of azotemia and/or oliguria, anuria, biliary ob-struction, gout, or uric calculi; an untreated hereditary deficiency of hypoxanthine-guanine-phosphoribosyl transferase such as Lesch-Nyhan syndrome; or a his-tory of latent or active tuberculosis or exposure to endemic areas within 8 weeks before purified protein derivative (PPD) skin testing at screening. A PPD test result indicating possible tuberculosis infection (≥5 mm) was also a cause for exclusion. Volunteers were excluded if they had received a depot injection or an implant of any drug within 3 months before the administration of study medication, or immunization with a live attenuated vaccine 1 month before dosing or planned vaccination during the course of the study; had any active infection; or had history of or active malignancy.

Subjects were considered eligible for enrollment in this study based on medical and medication histories, demographic and clinical data (including sex, age, race, ethnicity, weight, height, and BMI), vital sign measurements, 12-lead ECG, physical examination, urinary drug screen (E-Z Split Key cup kit [Innovacon, Inc., San Diego, California]), urinalysis for ampheta-mine, barbiturates, benzodiazepines, cocaine, ecstasy, marijuana, methadone, methamphetamine, opiate, and phencyclidine, serum pregnancy testing (female sub-jects), and clinical laboratory testing (hematology, biochemistry, urinalysis, HIV, hepatitis C virus antibod-ies, and hepatitis B surface antigen).

study DesignThe study design was 4-way replicate (ie, 2 test

periods and 2 reference periods). Clinical laboratory analysis was conducted at the time of the screening and poststudy procedures. Hematology and urinary pregnancy testing were also conducted before study periods 2, 3, and 4. Laboratory testing included he-matology (complete blood count with differential, hemoglobin, and hematocrit), biochemistry (albumin, alkaline phosphatase, alanine aminotransferase, aspar-tate aminotransferase, blood urea nitrogen, calcium, chloride, glucose, phosphorus, potassium, creatinine, sodium, total bilirubin, and total protein), urinalysis

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10 minutes at 4°C. Plasma was separated into 2 aliquots, which were flash-frozen at –80°C and subsequently transferred to a –80°C (–65°C to –90°C) freezer, pending shipment to the analytic facility.

At the end of the study, the frozen plasma aliquots (1 of 2) from the clinical facility, together with an in-ventory list and sufficient dry ice to maintain the ali-quots in a frozen state for ≥72 hours, were sent to the bioanalytic facility. The second set of aliquots was kept in the clinical facility and was to be sent only on request from the bioanalytic facility. The plasma ali-quots were received at the analytic facility in good condition and still frozen.

MMF and a deuterated analogue of MMF as inter-nal standard (MMF-d4, Toronto Research Chemicals, Toronto, Ontario, Canada) and MPA and a cyclopro-pane analogue of MPA as internal standard (MPA cyclopropane analogue, Synfine Research, Richmond Hill, Ontario, Canada) were measured using reverse LC-MS/MS.

MMF was extracted from an aliquot of human EDTA plasma using solid-phase extraction. Plasma samples were vortex-mixed and centrifuged at 3000 rpm (1900g) for 5 minutes at 4°C. Aliquots of plasma were collected into borosilicated tubes in samples of 200 µL each; 200 µL of Milli-Q water (Millipore, Billerica, Mas-sachusetts) containing internal standard and 800 µL of acetic acid were added. Samples were mixed for ~30 seconds and extracted using solid-phase extrac-tion with MCX oasis plates (Waters Corporation, Milford, Massachusetts). The extracted samples were eluted using 400 µL of acetonitrile/ammonium hy-droxide 95/5 vol/vol as elution solution and evapo-rated completely under a stream of nitrogen at 60°C on a TurboVap LV concentrator (Zymark Corpora-tion, Hopkinton, Massachusetts). The residues were reconstituted in 200 µL of reconstitution solution (mobile phase) (ammonium formate 1 mM [pH 3]/methanol [40/60 vol/vol]). MMF and its internal stan-dard were measured using LC-MS/MS. The separation was performed on a reversed-phase column (Zorbax SB-C18, 4.6 × 50 mm, 5-µm particle size; Agilent Tech-nologies, Santa Clara, California). The chromatographic separation was isocratically performed at room tem-perature at a flow rate of 1 mL/min.

MPA was extracted from an aliquot of human EDTA plasma using solid-phase extraction. Plasma samples were vortex-mixed and centrifuged at 3000 rpm (1900g) for 5 minutes at 4°C. Aliquots of plasma were col-

randomization scheme, a single dose of the test* (batch no. 4210701; expiration, November 2009) or reference† (batch no. M1764; expiration, April 2010) formulation of MMF 500 mg (1 oral film-coated tab-let) with 240 mL of water. A mouth check was per-formed for compliance verification per the protocol. Subjects fasted subsequently for a period of ≥4 hours. Smoking was prohibited from 2 hours before to 4 hours after administration and was controlled and docu-mented during each study period to ensure that sub-jects who were light smokers did not exceed the daily quantity of cigarettes authorized by the study proto-col (ie, <10 cigarettes per day).

blood sample Collection and AnalysisTreatment phases were separated by a washout

period of 14 days. For the measurement of MMF con-centrations in the plasma, blood samples were col-lected before and at 5, 10, 20, 30, 40, 50, 60, 75, 90, 105, 120, 135, and 150 minutes and 3, 4, 6, 7, 8, and 12 hours after study drug administration in each pe-riod. For MPA measurement, blood samples were col-lected before and 6, 10, 20, 30, 40, 50, 60, 75, 90, 105, 120, 135, and 150 minutes and 3, 4, 6, 7, 8, 12, 16, 24, 36 (±0.5), and 48 (±0.5) hours after study drug administration.

In each period a total of twenty 4-mL samples were obtained for the pharmacokinetic assessment of MMF; twenty-four 3-mL samples were obtained for the pharmacokinetic assessment of MPA. The total blood volume, including that collected for eligibility and tolerability purposes, did not exceed 659 mL. When deemed appropriate by the clinic staff, a dead-volume intravenous catheter was used for blood collection to avoid multiple skin punctures; otherwise, blood sam-ples were collected using direct venipuncture.

The dead-volume catheters were used to prevent clotting without the need for additives. Samples col-lected with this type of catheter did not require flush-ing of the lines after blood draws or discard of any volume before collection. A tube containing EDTA k2 was attached to the catheter and the blood was al-lowed to fill the tube. After blood collection, a clean stylet was inserted. The blood samples were cooled in an ice bath and centrifuged at 3000 rpm (~1900g) for

*Manufactured by Grupo Tecnimede, Sintra, Portugal.† Trademark: CellCept® (Roche Registration Ltd., Welwyn Garden City, United Kingdom).



curacy and precision ranged from 90.60% to 95.39% and 0.95% to 6.49%, respectively. The quality control means of recovery of MMF were 90.57%, 86.99%, and 89.14%, and for internal standard MMF-d4, the mean recovery was 87.12%. Both analyses were con-ducted using a robotic liquid handling system (Multi-PROBE II EX, PerkinElmer Inc., Waltham, Massachu-setts). No significant interferences were observed in tested matrices for MMF and MMF-d4.

The method for the determination of MPA concentra-tions showed a good linearity (r ≥ 0.9945) and allowed the quantification of MPA in human EDTA plasma within a range of 49.99 pg/mL to 19,955.00 ng/mL. The LLOQ was set at 19.95 ng/mL, with a signal-to-noise ratio of 124, in which accuracy and precision were 102.72% and 2.99%, respectively, when ana-lyzed 6 times. Between-run accuracy and precision ranged from 92.64% to 102.35% and 2.36% to 3.10%, respectively. Within-run accuracy and precision were 89.24% to 101.14% and 1.65% to 3.82%, respec-tively. The quality control means of recovery of MPA were 81.32%, 84.23%, and 84.76%, and for internal standard (MPA cyclopropane analogue), the mean recovery was 104.46%. Both analyses were conducted using the MultiPROBE II EX robotic liquid handling system. No significant interferences were observed in tested matrices for MPA and MPA cyclopropane analogue.

Pharmacokinetic and bioequivalence AnalysesTmax, AUC0–∞, ke, and t1/2 were determined for MMF

and MPA for informational purposes. The mean (SD), %CV, range, median, and interquartile range (IQR) of the plasma MMF and MPA concentrations were calcu-lated for the AUC0–t, AUC0–∞, Cmax, residual area, Tmax, elimination t1/2, ke, time at which ln-linear ke calcula-tion began, and time of last quantifiable concentra-tion. Pharmacokinetic calculations were made using Bioequiv version 3.50, a proprietary software developed and tested for bioequivalence studies at Anapharm, which performs noncompartmental analyses of phar-macokinetic parameters and statistical analyses (via SAS release 8.02, SAS Institute Inc.) according to the FDA,2

Health Product and Food Branch of “Health Canada,”7

and guidance from the European Agency for the Evaluation of Medicinal Products.8,9

Bioequivalence was assessed from the 90% CIs of the geometric ratios of the least squares means, obtained us-ing ANOVA of the ln-transformed Cmax and AUC0–t

lected into borosilicated tubes in samples of 50 µL each. One hundred microliters of Milli-Q water con-taining internal standard and 900 µL of buffer solution (phosphate trisodium, 100 mM, pH 12) was added. Samples were finally mixed for ~10 seconds and ex-tracted using solid-phase extraction with MAX oasis plates (Waters Corporation). The extracted samples were eluted using 400 µL of acetonitrile/formic acid (95/5 vol/vol) as elution solution and then evaporated completely under a stream of nitrogen at 60°C on a TurboVap LV concentrator (Zymark Corporation). The residues were reconstituted in 400 µL of reconsti-tution solution (ammonium formate 1 mM /methanol [32/68 vol/vol], formic acid 0.15%). Concentrations of MMA and its internal standard (MMA cyclopro-pane analogue) were measured using LC-MS/MS. The separation was performed on a reversed-phase col-umn (Zorbax SB-C18, internal diameter, 4.6 × 50 mm; 5-µm particle size; Agilent Technologies). The mo-bile phase was ammonium formate 1 mM/methanol (32/68 vol/vol), formic acid 0.15%. The chromatographic separation was isocratically performed at room tem-perature at a flow rate of 1 mL/min.

For both compounds (MMF and MPA), the modu-lar liquid chromatographic system was made up of an HTC-PAL autosampler (CTC Analytics AG, Zwingen, Switzerland), a high-pressure binary pump 1200 series (Agilent Technologies), and an API4000 spectrometer (MDS Sciex, Concord, Ontario, Canada).

The sample analysts were blinded to the randomi-zation scheme. Bioanalysis was performed under the Guideline for Good Laboratory Practice6 and the bio-analytical process validated according to US Food and Drug Administration (FDA) Guidance for Industry Bioanalytical Method Validation,2 therefore taking into consideration the study of linearity, precision, and ac-curacy intra-assay and interassay, selectivity, lower limit of quantitation (LLOQ), recovery, matrix effect, ionic suppression, dilution integrity, and stability un-der different conditions.

The method for MMF determination showed good linearity (r ≥ 0.9975) and allowed the quantification of MMF in human EDTA plasma within the range of 20.02 to 4004.00 pg/mL. The LLOQ was set at 19.90 pg/mL, with a signal-to-noise ratio of 35, where precision and accuracy were 102.86% and 4.77%, respectively, when analyzed 6 times. The between-run accuracy and precision ranged from 95.14% to 96.09% and 5.14% to 6.60%, respectively. The within-run ac-

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<0.05. Intrasubject %CVs were estimated for each formulation. Subject-by-formulation variance was al-so estimated. The ratio of geometric and means (A/B) 90% CIs were calculated for Cmax, AUC0–t, AUC0–∞and using the estimate statement. Nontransformed data of Tmax, elimination t1/2, and ke were also ana-lyzed using PROC MIXED.

rEsULTsstudy Population

Of the 103 subjects included in the tolerability population (64 men, 39 women; 101 white, 2 black; mean [SD] age, 38 [10] years; weight, 68.2 [9.1] kg), 100 constituted the pharmacokinetic population (Fig-ure 1 and Table I). Two participants withdrew use of the test drug in period 1 (1 to whom the clinical staff was unable to insert a catheter, and 1 due to mild herpes simplex virus infection considered unrelated to the drug). One participant withdrew during use of the reference drug in period 1 due to personal reasons. Two participants discontinued use of the test drug in period 2 (1 due to cough, which was considered mod-erate and possibly related to the drug, and 1 due to personal reasons). One participant was withdrawn during use of the reference drug in period 2 because the clinical staff was unable to insert a catheter. Four volunteers discontinued use of the test drug in period 3: 1 due to cellulite at the fifth finger of the left hand (judged moderate and deemed unrelated to the drug), 1 due to personal reasons, 1 due to absence from pe-riod 4, and 1 due to absence from period 3. Two par-ticipants withdrew use of reference drug in period 3: 1 was absent for period 4 and 1 withdrew due to con-current medication required for cystitis that was con-sidered moderate and possibly related to the drug.

Pharmacokinetic PropertiesThe mean plasma concentrations are plotted in

Figures 2 and 3, and the main pharmacokinetic pa-rameters appear in Tables II and III. No statistically significant differences in pharmacokinetic or bioavail-ability properties of MMF or MPA were detected be-tween the 2 formulations.

After the first administration of oral MMF 500 mg, mean (SD) Cmax values of 2858.90 (3183.75) and 2920.48 (2623.40) pg/mL with the test and reference formulations, respectively, were attained at median (IQR) Tmax of 0.500 (0.500) and 0.500 (0.167) hours. Mean AUC0–t and AUC0–∞ of 2145.67 (1636.45) and

for MMF and MPA. Per the European regulations for bioequivalence,8 the test and reference drugs were to be considered bioequivalent if the 90% CIs were within the range of 80% to 125%.

Tolerability AnalysisFor tolerability analysis, vital signs were measured

and laboratory testing was conducted. Vital signs measured at screening and after the clinical portion of the study was completed included seated SBP and DBP, heart rate, respiratory rate, and oral body tem-perature. Vital signs measured before and ~24 and 48 hours after study drug administration in each pe-riod were seated SBP and DBP and heart rate.

An adverse event (AE) was considered clinically sig-nificant if, based on medical judgment regarding the health of and tolerability in the subject, it led to a sub-stantial intervention, such as withdrawal from the clini-cal trial, stopping of study medication/investigational product treatment, dose reduction, or the need for sig-nificant additional concurrent therapy (eg, emergency department visit, antibiotic therapy for an infection, intravenous fluids used for dehydration).

statistical AnalysisA nonparametric Wilcoxon test was used for the

determination of statistically significant differences be-tween the 2 formulations for both MMF and MPA.

Sample size was estimated, with intrasubject %CVs for Cmax and AUC0–t of 23% and 49%, respectively, and an expected ratio between 0.91 and 1.10 taken into consideration. It was calculated that 92 subjects were required to show bioequivalence at a power of ≥80%, but the study was designed with 104 subjects, which accounted for possible dropouts.

Subjects were included in the pharmacokinetic analyses if they had completed ≥1 test and 1 reference study period. Subjects were included in the tolerability population if they received ≥1 dose of the test or refer-ence formulation.

For both MMF and MPA, ln-transformed Cmax, AUC0–t, and AUC0–∞ were analyzed using PROC MIXED in SAS. Therefore, the covariates in the lin-ear mixed-effects model included group, sequence, sequence*group, period (group), treatment, and treatment*group as fixed factors. Subject was entered into the model as a random effect. For all analyses, effects were considered statistically significant if the probability associated with F (test/reference ratio) was



After the first oral administration, the mean (SD) of MPA Cmax values were 14,965.96 (6407.22) and 15,884.98 (6380.70) ng/mL for the test and reference formulations, respectively. The median (IQR) Tmaxvalues were 0.667 (0.333) and 0.500 (0.333) hours. Mean AUC0–t and AUC0–∞ values were 29,712.19 (8301.24) and 33,111.54 (10,317.02) ng/mL/h with the test formulation and 29,888.52 (7982.68) and 33,187.01 (9945.36) ng/mL/h with the reference for-mulation (Table III).

After the second oral administration of MMF 500 mg, mean (SD) MPA Cmax values were 14,549.20 (6101.50) and 14,683.17 (6671.67) ng/mL with the

2376.53 (1711.93) pg/mL/h with the test formulation and 2225.99 (1552.87) and 2375.66 (1756.72) pg/mL/h with the reference formulation were attained (Table II).

After the second administration of oral MMF 500 mg, mean (SD) Cmax values of 3151.25 (3846.64) and 3037.23 (3104.52) pg/mL with the test and refer-ence formulations, respectively, were attained at me-dian (IQR) Tmax values of 0.500 (0.333) and 0.667 (0.333) hours. Mean AUC0–t and AUC0–∞ values were 2405.59 (1825.76) and 2462.04 (1547.46) pg/mL/h with the test formulation and 2394.89 (1674.35) and 2691.21 (2156.06) pg/mL/h with the reference formu-lation (Table II).

Discontinuedtreatment (n = 2) Catheter could not be inserted (n = 1) Infection (n = 1)

Discontinuedtreatment (n = 1) Catheter could not be inserted (n = 1)

Discontinuedtreatment (n = 4) Loss to follow-up (n = 2) AE (n = 1) Personal reasons (n = 1)

Received reference formulation

(n = 52)

Received testformulation

(n = 51)


(n = 49)

Received testformulation and

completed the study(n = 47)

Discontinuedtreatment (n = 1) Personal reasons (n = 1)

Discontinuedtreatment (n = 2) Cough (n = 1) Personal reasons (n = 1)

Discontinuedtreatment (n = 2) AE (n = 1) Loss to follow-up (n = 1)

Perio

d 2

Perio

d 1

Perio

d 3

Perio

d 4

Assessed for eligibility(N = 194)

Excluded (n = 91) Did not meet inclusion criteria (n = 44) Refused to participate (n = 2) Other reasons (n = 45)

Randomized(n = 103)

Received test formulation

(n = 51)


(n = 49)

Received test formulation

(n = 48)

Received reference formulation and

completed the study(n = 44)

Enro

llmen

t

Figure 1. Disposition of the subjects in this bioavailability study of a 500-mg dose of a generic formulation (test; manufactured by Grupo Tecnimede, Sintra, Portugal) and a branded formulation (reference; trademark: CellCept®, Roche Registration Ltd., Welwyn Garden City, United Kingdom) of mycophe-nolate mofetil. AE = adverse event.

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both the MMF and MPA profiles. In another subject, a lag time in absorption was found after the first ad-ministration of the reference formulation and the second administration of the test formulation. Second-ary elevation of MPA plasma concentration at ~4 to 12 hours, which has been attributed to enterohepatic recirculation,10 was shown in that subject’s plasma concentration–time curve. A multiple-peak profile was evident in 1 subject’s MMF and MPA curves (Figure 4).

bioequivalenceThe mean ratios and the 90% CIs of the ln-trans-

formed values of Cmax, AUC0–t, and AUC0–∞ are pre-sented in Table IV. For MMF, these values were 95.73 pg/mL (85.94–106.63), 96.93 pg/mL/h (91.94–102.20), and 99.12 pg/mL/h (93.15–105.48), respec-tively. For MPA, these values were 98.68 ng/mL (92.03–105.82), 98.99 ng/mL/h (97.42–100.59), and 98.91 ng/mL/h (96.96–100.90). These CIs were within the regulatory ranges for bioequivalence.

TolerabilityA total of 148 treatment-emergent AEs (TEAEs)

were reported in 66 of the 103 subjects (64.1%) in-cluded in the tolerability population. The breakdown by treatment group is as follows: 68 TEAEs reported in 43 of 102 subjects (42.2%) who received ≥1 dose of the test formulation, and 80 TEAEs were reported in 48 of 101 subjects (47.5%) who received ≥1 dose of the reference formulation (Table V).

The most commonly reported AEs were procedural pain (13/102 [12.7%] and 10/101 [9.9%] with the test and reference formulations, respectively), proce-dural site reacton (12 [11.8%] and 4 [4.0%]), and somnolence (7 [6.9%] and 14 [13.9%]).

Of the 148 TEAEs reported, 125 were rated as mild and 23 were rated as moderate. The relationships of 54 TEAEs were considered possibly related, 8 as re-motely possibly related, and 86 as unrelated to the study drug.

No deaths or serious AEs were reported during this study. Clinically significant AEs were cystitis, her-pes simplex, cellulitis, and respiratory tract infection (1 subject [1%] each). The health of these subjects was not considered to be at risk during the study.

Vital sign measurements and laboratory testing on conclusion of the clinical portion of the study found no significant changes in any subject’s state of health.

test and reference formulations, respectively. The median (IQR) Tmax values were 0.667 (0.283) and 0.667 (0.500) hours. Mean AUC0–t and AUC0–∞ were 29,444.85 (8075.52) and 32,195.74 (10,077.77) ng/mL/h with the test formulation and 29,910.48 (8292.20) and 33,375.82 (10,007.80) ng/mL/h with the reference for-mulation (Table III). The residual area obtained with both the test and reference products for the parent com-pound was <20% (mean, <10%).

Figure 4 shows individual concentration–time curves for MMF and MPA in 3 individuals after the administration of the test and reference formulations. One subject had a single peak absorption pattern in

Table I. Baseline demographic characteristics of clinical trial subjects.

Pharmacokinetic Tolerability Population Population Characteristic (n = 100) (n = 103)

Age, y Mean (SD) 38 (10) 38 (10) Range 20–55 20–55 Median 40 39

Age group, no. (%) 18–<40 y 51 (51.0) 53 (51.5) 40–<65 y 49 (49.0) 50 (48.5)

Sex, no. (%) Male 62 (62.0) 64 (62.1) Female 38 (38.0) 39 (37.9)

Race, no. (%) White 98 (98.0) 101 (98.1) Black 2 (2.0) 2 (1.9)

Height, cm Mean (SD) 168.4 (9.00) 168.3 (9.00) Range 150.0–188.0 150.0–188.0 Median 169.3 169.0

Weight, kg Mean (SD) 68.2 (9.1) 68.2 (9.1) Range 47.0–94.8 47.0–94.8 Median 68.3 68.4

BMI, kg/m2

Mean (SD) 24.0 (1.8) 24.0 (1.8) Range 20.0–26.9 20.0–26.9 Median 24.3 24.3

BMI = body mass index.



and MPA both as highly variable drugs because after the 4-way replicate study, the intrasubject %CV for Cmax was >30% with both analytes (63.83% and 33.47%, respectively).14

MPA pharmacokinetic variability patterns have previously been described in adult kidney transplant recipients.10 Data from the present study were consis-tent with those from that report10 and extend to healthy individuals, supporting that the pharmaco-kinetic properties of MMF might be erratic, as indi-cated by the intrasubject %CVs for Cmax and by the individual concentration–time curves.

The concentration–time curve absorption phase of the study design was considered well characterized, and the sampling scheme was considered adequate for the determination of AUC0–t and Cmax (ie, of sufficient duration to fully assess the elimination phase of MMF and MPA) given that the residual area with both the test and reference products was <20% (mean, <10%).

Elimination t1/2 for MPA was in line with data found in previously published literature (ie, between 11 and

DIsCUssIoNMMF, an inactive prodrug of MPA, is absorbed from the gastrointestinal tract, undergoing presystemic de-esterification to become MPA, the active moiety. MMF has been reported as undetectable in plasma after oral administration.10,12 However, the development of a more sensitive bioanalytical assay allows the detec-tion of the parent compound in plasma, even though concentrations are <1% that of MPA. Accordingly, this study was able to detect MMF in plasma and to characterize its main pharmacokinetic parameters. With both MMF and MPA, Tmax, AUC0–∞, ke, and t1/2were determined for informational purposes. On nonparametric Wilcoxon testing, no statistically sig-nificant differences in MMF or MPA were detected between treatments.

MPA pharmacokinetics have been described as complex and erratic, with large between- and within-subject variability (>30%).2,3,10 The data obtained from the present study are consistent with that from previously published reports3,13 and characterize MMF

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Figure 2. Mean plasma mycophenolate mofetil (MMF) concentrations obtained after single 500-mg dose administration of a generic formulation (test; manufactured by Grupo Tecnimede, Sintra, Portugal) and a branded formulation (reference; trademark: CellCept®, Roche Registration Ltd., Welwyn Garden City, United Kingdom).

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ever, the health of these subjects was not considered to have been at risk during the study.

Bioequivalence studies with replicate design are scarce based on a PubMed search, using the key terms bioequivalence and replicate. This study design allowed the assessment of true intrasubject %CVs of the test or reference formulation when using a 4-period crossover scheme, and the assessment of true within-subject %CV of both formulations, when the full replicate design was applied. Despite the fact that this study design reduced the number of sub-jects exposed to the drug, by increasing the duration of exposure, it was more time consuming than the standard 2-way crossover approach, involved a larger volume of blood samples taken per subject, and increased the dropout rate (with longer study periods).15,16

The facts that the study medication was adminis-tered as a single dose and the dose administered was 500 mg (compared with the ≥1-g dose recommended by the manufacturer) might explain the low rates of

19 hours),10 reinforcing the adequate concentration–time curve characterization and optimum selection of the washout period of 14 days, which was considered adequate to allow complete elimination of the drug be-fore subsequent dosing, avoiding carryover effects. Hence, no predose carryover concentrations were ob-served in periods 2, 3, or 4.

The study design was considered adequate to detect a significant difference between the test and reference formulations in cases in which the 90% CIs obtained for AUC0–t, AUC0–∞, and Cmax were within the Euro-pean regulatory requirements for bioequivalence, 80% to 125%.8,9 No statistically significant differ-ences were found between the 2 formulations in the tested population. No sequence, period, or treatment effects were verified for AUC0–t, AUC0–∞, or Cmax. The 2 formulations met the European regulatory criteria for bioequivalence in terms of rate and extent of absorption.8,9

No deaths or serious AEs were reported during this study. Three clinically significant AEs occurred; how-

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Figure 3. Mean plasma mycophenolic acid (MPA) concentrations obtained after single 500-mg dose adminis-tration of a generic formulation (test; manufactured by Grupo Tecnimede, Sintra, Portugal) and a branded formulation (reference; trademark: CellCept®, Roche Registration Ltd., Welwyn Garden City, United Kingdom) of the inactive prodrug mycophenolate mofetil.

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herapeuticsTable II. Pharmacokinetic properties of generic (test)* and branded (reference)† oral formulations of mycophenolate mofetil 500 mg after first and second administration in healthy subjects under fasting conditions.

Test Reference

No. of No. of Parameter Patients Mean (SD) Median %CV IQR Patients Mean (SD) Median %CV IQR

First administration AUC0–t, pg/mL/h 100 2145.67 (1636.45) 1706.50 76.27 1460.40 100 2225.99 (1552.87) 1833.72 69.76 1608.48 AUC0–∞, pg/mL/h 80 2376.53 (1711.93) 1978.16 72.03 1428.55 77 2375.66 (1756.72) 1928.77 73.95 1587.12 Residual area, % 80 5.59 (5.65) 3.55 101.00 5.45 77 5.06 (5.37) 3.23 106.29 4.11 Cmax, pg/mL 100 2858.90 (3183.75) 1882.41 111.36 20,14.47 100 2920.48 (2623.40) 2188.15 89.83 2330.98 Tmax, h 100 – 0.500 – 0.500 100 – 0.500 – 0.167 t1/2, h 80 2.29 (1.73) 1.89 75.30 1.83 77 1.98 (1.35) 1.63 68.19 1.63 ke, 1/h 80 0.4855 (0.3563) 0.3666 73.38 0.3921 77 0.5282 (0.3418) 0.4249 64.70 0.4544

Second administration AUC0–t, pg/mL/h 93 2405.59 (1825.76) 1806.58 75.90 1659.45 95 2394.89 (1674.35) 1941.58 69.91 1316.12 AUC0–∞, pg/mL/h 68 2462.04 (1547.46) 1978.77 62.85 1631.59 75 2691.21 (2156.06) 2072.79 80.11 1392.79 Residual area, % 68 5.69 (6.68) 3.24 117.39 4.36 75 6.03 (7.84) 3.32 130.15 4.04 Cmax, pg/mL 93 3151.25 (3846.64) 2133.16 122.07 2178.86 95 3037.23 (3104.52) 2352.18 102.22 2359.51 Tmax, h 93 – 0.500 – 0.333 95 – 0.667 – 0.333 t1/2, h 68 2.58 (1.93) 2.08 75.04 2.10 75 2.24 (1.57) 1.82 70.00 1.80 ke, 1/h 68 0.4577 (0.3718) 0.3326 81.24 0.2952 75 0.4625 (0.3201) 0.3816 69.20 0.3834

IQR = interquartile range.*Manufactured by Grupo Tecnimede, Sintra, Portugal. † Trademark: Cellcept® (Roche Registration Ltd., Welwyn Garden City, United Kingdom).

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Table III. Pharmacokinetic properties of generic (test)* and branded (reference)† oral formulations of mycophenolic acid 500 mg after first and second administration in healthy subjects under fasting conditions.

Test Reference

No. of No. of Parameter Patients Mean (SD) Median %CV IQR Patients Mean (SD) Median %CV IQR

First administration AUC0–t, ng/mL/h 100 29,712.19 (8301.24) 28,984.99 27.94 10,162.76 100 29,888.52 (7982.68) 28,155.84 26.71 11,811.79 AUC0–∞, ng/mL/h 82 33,111.54 (10,317.02) 31,507.91 31.16 11,998.93 80 33,187.01 (9945.36) 31,311.98 29.97 12,727.83 Residual area, % 82 10.09 (7.93) 7.98 78.58 6.66 80 9.43 (6.09) 7.94 64.59 5.61 Cmax, ng/mL 100 14,965.96 (6407.22) 14,459.65 42.81 6681.55 100 15,884.98 (6380.70) 15,686.30 40.17 8746.42 Tmax, h 100 – 0.667 – 0.333 100 – 0.500 – 0.333 t1/2, h 82 16.33 (6.33) 15.50 38.79 7.65 80 16.29 (6.31) 14.84 38.72 5.34 ke, 1/h 82 0.0486 (0.0177) 0.0447 36.45 0.0231 80 0.0478 (0.0162) 0.0467 33.98 0.0158

Second administration AUC0–t, ng/mL/h 95 29,444.85 (8075.52) 28,792.60 27.43 12,024.80 93 29,910.48 (8292.20) 29,188.79 27.72 10,127.63 AUC0–∞, ng/mL/h 82 32,195.74 (10,077.77) 12,024.80 31.30 13,612.31 80 33,375.82 (10,007.80) 32,349.62 29.99 13,811.60 Residual area, % 82 8.77 (5.16) 7.62 58.87 6.12 80 9.57 (6.31) 7.59 65.89 7.05 Cmax, ng/mL 95 14,549.20 (6101.50) 14,003.26 41.94 7913.76 93 14,683.17 (6671.67) 14,427.30 45.44 8554.34 Tmax, h 95 – 0.667 – 0.283 93 – 0.667 – 0.500 t1/2, h 82 15.88 (5.86) 14.51 36.87 7.02 80 16.19 (5.64) 15.58 34.85 6.90 ke, 1/h 82 0.0492 (0.0168) 0.0478 34.13 0.0232 80 0.0484 (0.0187) 0.0445 38.66 0.0215

IQR = interquartile range. * Manufactured by Grupo Tecnimede, Sintra, Portugal. † Trademark: CellCept® (Roche Registration Ltd., Welwyn Garden City, United Kingdom).



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Figure 4. (A and B) Two selected individual plasma concentration–time curves after single 500-mg dose administration of a generic formulation (test; manufactured by Grupo Tecnimede, Sintra, Portugal) and branded formulation (reference; trademark: CellCept®, Roche Registration Ltd., Welwyn Garden City, United Kingdom) of mycophenolate mofetil (MMF).

(continued)

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Figure 4 (continued). Two selected individual plasma concentration–time curves after single 500-mg dose administration of a generic formulation (test; manufactured by Grupo Tecnimede, Sintra, Portugal) and branded formulation (reference; trademark: CellCept®, Roche Registration Ltd., Welwyn Garden City, United Kingdom) of (C) mycophenolate mofetil (MMF) and of its active metabolite, (D) myco-phenolic acid (MPA).

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Figure 4 (continued). (E and F) Two selected individual plasma concentration–time curves of the active me-tabolite mycophenolic acid (MPA) after single 500-mg dose administration of a generic formulation (test; manufactured by Grupo Tecnimede, Sintra, Portugal) and branded formulation (reference; trademark: CellCept®, Roche Registration Ltd., Welwyn Garden City, United Kingdom) of myco-phenolate mofetil.

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Table IV. Mean treatment ratios for the pharmacokinetic properties of generic (test)* and branded (reference)† oral formulations of mycopheno-late mofetil (MMF) 500 mg and its active metabolite, mycophenolic acid (MPA), after f irst and second administration in healthy subjects under fasting conditions.‡

MMF MPA

WS %CV§ WS %CV§

Parameter Test Reference Ratio (90% CI), % Test Reference Ratio (90% CI), %

AUC0–t 28.90 pg ⋅ h/mL 25.44 pg ⋅ h/mL 96.93 pg ⋅ h/mL (91.94–102.20) 9.51 ng ⋅ h/mL 9.49 ng ⋅ h/mL 98.99 ng ⋅ h/mL (97.42–100.59)

AUC0–∞ 20.18 pg ⋅ h/mL 29.04 pg ⋅ h/mL 99.12 pg ⋅ h/mL (93.15–105.48) 11.07 ng ⋅ h/mL 9.30 ng ⋅ h/mL 98.91 ng ⋅ h/mL (96.96–100.90)

Cmax 63.83 pg/mL 61.04 pg/mL 95.73 pg/mL (85.94–106.63) 33.47 ng/mL 48.83 ng/mL 98.68 mL (92.03–105.82)

WS = within subject. * Manufactured by Grupo Tecnimede, Sintra, Portugal. † Trademark: CellCept® (Roche Registration Ltd., Welwyn Garden City, United Kingdom). ‡ Values calculated using natural logarithm–transformed data. § Intrasubject values.



Table V. Characterization of the adverse events after the administration of generic (test)* and branded (reference)† oral formulations of mycophenolate mofetil (MMF) 500 mg in healthy subjects under fasting conditions. Values are number (%) of subjects.‡§

Test Reference System Organ Class/Preferred Term∥ (n = 102) (n = 101)

Cardiac disorders 1 (1.0) Palpitations 0 1 (1.0)

Gastrointestinal disorders 2 (2.0) 4 (4.0) Nausea 1 (1.0) 2 (2.0) Diarrhea 1 (1.0) 1 (1.0) Upper abdominal pain 0 1 (1.0) Oral pain 0 1 (1.0)

General disorders and administration site conditions 1 (1.0) 2 (2.0) Chest discomfort 1 (1.0) 0 Fatigue 0 2 (2.0)

Infections and infestations 5 (4.9) 1 (1.0) Cellulitis 1 (1.0) 0 Herpes simplex 1 (1.0) 0 Oral herpes 1 (1.0) 0 Respiratory tract infection 1 (1.0) 0 Rhinitis 1 (1.0) 0 Cystitis 0 1 (1.0)

Injury, poisoning, and procedural complications 26 (25.5) 19 (18.8) Procedural pain 13 (12.7) 10 (9.9) Procedural site reaction 12 (11.8) 4 (4.0) Postprocedural hematoma 3 (2.9) 4 (4.0) Postprocedural swelling 1 (1.0) 2 (2.0) Skin laceration 1 (1.0) 2 (2.0) Thermal burn 1 (1.0) 1 (1.0) Procedural dizziness 1 (1.0) 0 Animal bite 1 (1.0) 0 Contusion 0 1 (1.0)

Vital signs and laboratory parameters 5 (4.9) 6 (5.9) Blood pressure decreased 2 (2.0) 4 (4.0) Heart rate decreased 1 (1.0) 1 (1.0) Heart rate increased 1 (1.0) 1 (1.0) White blood cell count increased 1 (1.0) 0

Musculoskeletal and connective tissue disorders 1 (1.0) 3 (2.9) Back pain 1 (1.0) 1 (1.0) Musculoskeletal pain 0 2 (2.0)

Nervous system disorders 11 (10.8) 22 (21.8) Somnolence 7 (6.9) 14 (13.9) Headache 4 (3.9) 8 (7.9) Dizziness 1 (1.0) 0 Hypoesthesia 0 1 (1.0) Neuralgia 0 1 (1.0)

(continued)

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http://www.fda.gov/downloads/Drugs/Guidance Compl ianceRegulator yInformation/Guidances/UCM070107.pdf. Accessed October 7, 2009.

3. Franco Spinola AC, Almeida S, Filipe A, Neves R. Limita-tions of Non-Magic Bullets Compounds in Bioequivalence Assessment. How Can This Enhance Knowledge Towards the Development of Generic Products. The Mycophenolate Mofetil Case. http://www.ehrlich-2008.org/Programm_final.pdf. Accessed October 7, 2009.

4. World Medical Association (WMA). World Medical As-sociation Declaration of Helsinki—Ethical Principles for Medical Research Involving Human Subjects. http://www.wma.net/en/30publications/10policies/b3/index.html. Accessed October 7, 2009.

5. European Medicines Agency for the Evaluation of Medici-nal Products (EMEA). ICH Topic E 6 (R1). Guideline for Good Clinical Practice. http://www.emea.europa.eu/pdfs/human/ich/013595en.pdf. Accessed October 7, 2009.

6. The Spanish Agency of Medicinal and Sanitary Products. Royal Decree 822 of May 28, 1993, that Establishes the Principles of Good Laboratory Practice and Chemical Ap-plication in the Accomplishment of Nonclinical Studies on Substances and Products. http://www.aemps.es/actividad/legislacion/espana/docs/RCL_1993_1646Vigente.pdf. Accessed March 4, 2010.

7. Health Canada. Guidance for Industry: Conduct and Analysis of Bioavailability and Bioequivalence Studies—Part A: Oral Dosage Formulations Used for Systemic Effects. http://www.hc-sc.gc.ca/dhp-mps/prodpharma/

gastrointestinal disturbances and blood dyscrasias found in this study.

CoNCLUsIoNsIn this open-label study in healthy subjects, the test and reference formulations of MMF 500-mg tablets met the European regulatory definition of bioequiva-lence based on the rate and extent of absorption of a single dose under fasting conditions. Both formula-tions were well tolerated.

ACkNowLEDgMENTsAll of the authors are employees or vendors of Grupo Tecnimede, the manufacturer of the test product used in this study. The authors have indicated that they have no other conflicts of interest regarding the con-tent of this article.

rEFErENCEs1. The European Agency for the Evaluation of Medicinal

Products (EMEA). European Public Assessment Report. Mycophenolate Mofetil, Cellcept. http://www.emea. europa.eu/humandocs/PDFs/EPAR/Cellcept/emea- combined-h82en.pdf. Accessed October 7, 2009.

2. US Dept of Health and Human Services, Food and Drug Administration, Center for Drug Evaluation and Research (CDER), Center for Veterinary Medicine (CVM). Guidance for Industry. Bioanalytical Method Validation.

Respiratory, thoracic, and mediastinal disorders 1 (1.0) 2 (2.0) Pharyngolaryngeal pain 1 (1.0) 2 (2.0)

Skin and subcutaneous tissue disorders 2 (2.0) 2 (2.0) Erythema 1 (1.0) 1 (1.0) Skin lesion 1 (1.0) 0 Pruritus 0 1 (1.0)

Vascular disorders 1 (1.0) 1 (1.0) Hot flush 1 (1.0) 1 (1.0)

Total 43 (42.2) 48 (47.5)

* Manufactured by Grupo Tecnimede, Sintra, Portugal. † Trademark: CellCept® (Roche Registration Ltd., Welwyn Garden City, United Kingdom). ‡ Each subject was counted only once in each adverse-event category, regardless of the number of occurrences. § Some patients had >1 adverse event. ∥ Medical Dictionary for Regulatory Activities.11

Table V (continued).

Test Reference System Organ Class/Preferred Term∥ (n = 102) (n = 101)



lency assessment, pros and cons: Bioavailabilities of the antidiabetic drugs pioglitazone and glimepiride present in a fixed-dose combina-tion formulation. J Clin Pharmacol. 2007;47:806–816.

EUFEPS BABP Network open discus-sion: Revised European guidelines on bioequivalence. Bonn, Germany: January 14–15, 2009.

16. Karim A, Zhao Z, Slater M, et al. Replicate study design in bioequiva-

applic-demande/guide-ld/bio/bio- a-eng.php. Accessed October 7, 2009.

8. Committee for Proprietary Medicinal Products (CPMP). Draft Guideline on the investigation of bioequivalence (CPMP/EWP/QWP/1401/98R). http://www.emea.europa.eu/pdfs/human/ewp/056095en.pdf. Ac-cessed October 7, 2009.

9. Therapeutics Goods Administration (TGA). CPMP Guideline—As Adopt- ed in Australia by the TGA—With Amendment. Note for Guidance on the Investigation of Bioavailability and Bioequivalence (CPMP/EWP/QWP/1401/98). http://www.tga.gov.au/DOCS/pdf/euguide/ewp/ 140198entga.pdf. Accessed October 7, 2009.

10. Staatz CE, Tett SE. Clinical pharma-cokinetics and pharmacodynamics of mycophenolate in solid organ transplant recipients. Clin Pharmaco- kinet. 2007;46:13–58.

11. US Food and Drug Administration. Medical Dictionary for Regulatory Activities. http://www.meddramsso.com/MSSOWeb/index.htm. Accessed October 7, 2009.

12. Armstrong VW, Tenderich G, Ship-kova M, et al. Pharmacokinetics and bioavailability of mycophenolic acid after intravenous administration and oral administration of myco-phenolate mofetil to heart transplant recipients. Ther Drug Monit. 2005; 27:315–321.

13. Levesque E, Benoit-Biancamano MO, Delage R, et al. Pharmacokinetics of mycophenolate mofetil and its glucuronide metabolites in healthy volunteers. Pharmacogenomics. 2008; 9:869–879.

14. Blume HH, Midha KK. Bio- International 92, conference on bioavailability, bioequivalence, and pharmacokinetic studies. J Pharm Sci. 1993;82:1186–1189.

15. Spínola AC, Almeida S, Filipe A, Neves R. Highly variable drugs and highly variable drug products. Briefing on regulatory and scientific perspectives.

Address correspondence to: Susana Almeida, Medical Department, Grupo Tecnimede, Sociedade Tecnico-Medicinal S.A., Zona Industrial da Abrunheira, R. da Tapada Grande, n.°2 Abrunheira, 2710-089 Sintra, Portugal. E-mail: [email protected]

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Mycophenolate mofetil 500-mg tablet under fasting conditions: Single-dose, randomized-sequence, open-label, four-way replicate crossover, bioequivalence study in healthy subjects