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HIGHLIGHTS OF PRESCRIBING INFORMATION These highlights do not include all the information needed to use ARICEPT safely and effectively. See full prescribing information for ARICEPT.
ARICEPT®^ (donepezil hydrochloride) tablets, for oral use ARICEPT ODT (donepezil hydrochloride) orally disintegrating tablets Initial U.S. Approval: 1996
------------------------------INDICATIONS AND USAGE------------------------ ARICEPT is an acetylcholinesterase inhibitor indicated for the treatment of dementia of the Alzheimer’s type. Efficacy has been demonstrated in patients with mild, moderate, and severe Alzheimer’s Disease (1)
------------------------DOSAGE AND ADMINISTRATION----------------------
- Mild to Moderate Alzheimer’s Disease: 5 mg to 10 mg once daily (2.1)
- Moderate to Severe Alzheimer’s Disease: 10 mg to 23 mg once daily (2.2)
------------------------DOSAGE FORMS AND STRENGTHS-------------------
- Tablets: 5 mg, 10 mg, and 23 mg (3)
- Orally Disintegrating Tablets (ODT): 5 mg and 10 mg (3)
----------------------------------CONTRAINDICATIONS--------------------------- Known hypersensitivity to donepezil hydrochloride or to piperidine derivatives (4)
-------------------------WARNINGS AND PRECAUTIONS---------------------
- Cholinesterase inhibitors are likely to exaggerate succinylcholine-type muscle relaxation during anesthesia (5.1)
- Cholinesterase inhibitors may have vagotonic effects on the sinoatrial and atrioventricular nodes manifesting as bradycardia or heart block (5.2)
- ARICEPT can cause vomiting. Patients should be observed closely at initiation of treatment and after dose increases (5.3) - Patients should be monitored closely for symptoms of active or occult gastrointestinal (GI) bleeding, especially those at increased risk for developing ulcers (5.4) - The use of ARICEPT in a dose of 23 mg once daily is associated with weight loss (5.5) - Cholinomimetics may cause bladder outflow obstructions (5.6) - Cholinomimetics are believed to have some potential to cause generalized convulsions (5.7) - Cholinesterase inhibitors should be prescribed with care to patients with a history of asthma or obstructive pulmonary disease (5.8) ------------------------------ADVERSE REACTIONS------------------------------- Most common adverse reactions in clinical studies of ARICEPT are nausea, diarrhea, insomnia, vomiting, muscle cramps, fatigue, and anorexia (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Eisai Inc. at 1-888-274-2378 (fax 1-201-746-3207) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. ------------------------------DRUG INTERACTIONS------------------------------- - Cholinesterase inhibitors have the potential to interfere with the activity of anticholinergic medications (7.1) - A synergistic effect may be expected with concomitant administration of succinylcholine, similar neuromuscular blocking agents, or cholinergic agonists (7.2) -----------------------USE IN SPECIFIC POPULATIONS------------------------ Pregnancy: Based on animal data, may cause fetal harm (8.1) See 17 for PATIENT COUNSELING INFORMATION and FDA- approved patient labeling. Revised: 12/
FULL PRESCRIBING INFORMATION: CONTENTS*
1 INDICATIONS AND USAGE 2 DOSAGE AND ADMINISTRATION 2.1 Dosing in Mild to Moderate Alzheimer’s Disease 2.2 Dosing in Moderate to Severe Alzheimer’s Disease 2.3 Administration Information 3 DOSAGE FORMS AND STRENGTHS 4 CONTRAINDICATIONS 5 WARNINGS AND PRECAUTIONS 5.1 Anesthesia 5.2 Cardiovascular Conditions 5.3 Nausea and Vomiting 5.4 Peptic Ulcer Disease and GI Bleeding 5.5 Weight Loss 5.6 Genitourinary Conditions 5.7 Neurological Conditions: Seizures 5.8 Pulmonary Conditions 6 ADVERSE REACTIONS 6.1 Clinical Trials Experience 6.2 Postmarketing Experience 7 DRUG INTERACTIONS 7.1 Use with Anticholinergics 7.2 Use with Cholinomimetics and Other Cholinesterase Inhibitors
8 USE IN SPECIFIC POPULATIONS 8.1 Pregnancy 8.2 Lactation 8.4 Pediatric Use 8.5 Geriatric Use 8.6 Lower Weight Individuals 10 OVERDOSAGE 11 DESCRIPTION 12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action 12.3 Pharmacokinetics 13 NONCLINICAL TOXICOLOGY 13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility 13.2 Animal Toxicology and/or Pharmacology 14 CLINICAL STUDIES 14.1 Mild to Moderate Alzheimer’s Disease 14.2 Moderate to Severe Alzheimer’s Disease 16 HOW SUPPLIED/STORAGE AND HANDLING 16.1 ARICEPT (^) Tablets 16.2 ARICEPT ODT 17 PATIENT COUNSELING INFORMATION *Sections or subsections omitted from the full prescribing information are not listed.
FULL PRESCRIBING INFORMATION
1 INDICATIONS AND USAGE
ARICEPT is indicated for the treatment of dementia of the Alzheimer’s type. Efficacy has been demonstrated in patients with mild, moderate, and severe Alzheimer’s disease.
2 DOSAGE AND ADMINISTRATION 2.1 Dosing in Mild to Moderate Alzheimer’s Disease The recommended starting dosage of ARICEPT is 5 mg administered once per day in the evening, just prior to retiring. The maximum recommended dosage of ARICEPT in patients with mild to moderate Alzheimer’s disease is 10 mg per day. A dose of 10 mg should not be administered until patients have been on a daily dose of 5 mg for 4 to 6 weeks.
2.2 Dosing in Moderate to Severe Alzheimer’s Disease The recommended starting dosage of ARICEPT is 5 mg administered once per day in the evening, just prior to retiring. The maximum recommended dosage of ARICEPT in patients with moderate to severe Alzheimer’s disease is 23 mg per day. A dose of 10 mg should not be administered until patients have been on a daily dose of 5 mg for 4 to 6 weeks. A dose of 23 mg per day should not be administered until patients have been on a daily dose of 10 mg for at least 3 months.
2.3 Administration Information ARICEPT should be taken in the evening, just prior to retiring. ARICEPT can be taken with or without food.
The ARICEPT 23 mg tablet should not be split, crushed, or chewed.
Allow ARICEPT ODT to dissolve on the tongue and follow with water.
3 DOSAGE FORMS AND STRENGTHS ARICEPT is supplied as film-coated, round tablets containing 5 mg, 10 mg, or 23 mg of donepezil hydrochloride.
- The 5 mg tablets are white. The strength, in mg (5), is debossed on one side and ARICEPT is debossed on the other side.
- The 10 mg tablets are yellow. The strength, in mg (10), is debossed on one side and ARICEPT is debossed on the other side.
- The 23 mg tablets are reddish. The strength, in mg (23), is debossed on one side, and ARICEPT is debossed on the other side.
ARICEPT ODT is supplied as round tablets containing either 5 mg or 10 mg of donepezil hydrochloride.
- The 5 mg orally disintegrating tablets are white. The strength, in mg (5), is debossed on one side and ARICEPT is debossed on the other side.
- The 10 mg orally disintegrating tablets are yellow. The strength, in mg (10), is debossed on one side and ARICEPT is debossed on the other side.
4 CONTRAINDICATIONS ARICEPT is contraindicated in patients with known hypersensitivity to donepezil hydrochloride or to piperidine derivatives.
5.8 Pulmonary Conditions Because of their cholinomimetic actions, cholinesterase inhibitors should be prescribed with care to patients with a history of asthma or obstructive pulmonary disease.
6 ADVERSE REACTIONS The following serious adverse reactions are described below and elsewhere in the labeling:
- Cardiovascular Conditions [see Warnings and Precautions (5.2)]
- Nausea and Vomiting [see Warnings and Precautions (5.3)]
- Peptic Ulcer Disease and GI Bleeding [see Warnings and Precautions (5.4)]
- Weight Loss [see Warnings and Precautions (5.5)]
- Genitourinary Conditions [see Warnings and Precautions (5.6)]
- Neurological Conditions: Seizures [see Warnings and Precautions (5.7)]
- Pulmonary Conditions [see Warnings and Precautions (5.8)]
6.1 Clinical Trials Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
ARICEPT has been administered to over 1,700 individuals during clinical trials worldwide. Approximately 1200 of these patients have been treated for at least 3 months and more than 1,000 patients have been treated for at least 6 months. Controlled and uncontrolled trials in the United States included approximately 900 patients. In regards to the highest dose of 10 mg/day, this population includes 650 patients treated for 3 months, 475 patients treated for 6 months, and 116 patients treated for over 1 year. The range of patient exposure is from 1 to 1,214 days.
Mild to Moderate Alzheimer’s Disease
Adverse Reactions Leading to Discontinuation The rates of discontinuation from controlled clinical trials of ARICEPT due to adverse reactions for the ARICEPT 5 mg/day treatment groups were comparable to those of placebo treatment groups at approximately 5%. The rate of discontinuation of patients who received 7-day escalations from 5 mg/day to 10 mg/day was higher at 13%.
The most common adverse reactions leading to discontinuation, defined as those occurring in at least 2% of patients and at twice or more the incidence seen in placebo patients, are shown in Table 1.
Table 1. Most Common Adverse Reactions Leading to Discontinuation in Patients with Mild to Moderate Alzheimer’s Disease
Adverse Reaction Placebo (n=355) %
5 mg/day ARICEPT (n=350) %
10 mg/day ARICEPT (n=315) % Nausea 1 1 3 Diarrhea 0 <1 3 Vomiting <1 <1 2
Most Common Adverse Reactions
The most common adverse reactions, defined as those occurring at a frequency of at least 5% in patients receiving 10 mg/day and twice the placebo rate, are largely predicted by ARICEPT’s cholinomimetic effects. These include nausea, diarrhea, insomnia, vomiting, muscle cramp, fatigue, and anorexia. These adverse reactions were often transient, resolving during continued ARICEPT treatment without the need for dose modification.
There is evidence to suggest that the frequency of these common adverse reactions may be affected by the rate of titration. An open-label study was conducted with 269 patients who received placebo in the 15- and 30-week studies. These patients were titrated to a dose of 10 mg/day over a 6-week period. The rates of common adverse reactions were lower than those seen in patients titrated to 10 mg/day over one week in the controlled clinical trials and were comparable to those seen in patients on 5 mg/day.
See Table 2 for a comparison of the most common adverse reactions following one and six week titration regimens.
Table 2. Comparison of Rates of Adverse Reactions in Mild to Moderate Patients Titrated to 10 mg/day over 1 and 6 Weeks No titration One week titration
Six week titration Adverse Reaction
Placebo (n=315) %
5 mg/day (n=311) %
10 mg/day (n=315) %
10 mg/day (n=269) % Nausea 6 5 19 6 Diarrhea 5 8 15 9 Insomnia 6 6 14 6 Fatigue 3 4 8 3 Vomiting 3 3 8 5 Muscle cramps 2 6 8 3 Anorexia 2 3 7 3
Table 3 lists adverse reactions that occurred in at least 2% of patients in pooled placebo-controlled trials who received either ARICEPT 5 mg or 10 mg and for which the rate of occurrence was greater for patients treated with ARICEPT than with placebo. In general, adverse reactions occurred more frequently in female patients and with advancing age.
Table 3. Adverse Reactions in Pooled Placebo-Controlled Clinical Trials in Mild to Moderate Alzheimer’s Disease Adverse Reaction Placebo (n=355) %
ARICEPT
(n=747) % Percent of Patients with any Adverse Reaction
Nausea 6 11 Diarrhea 5 10 Headache 9 10
Table 4 lists adverse reactions that occurred in at least 2% of patients in pooled placebo-controlled trials who
received ARICEPT 5 mg or 10 mg and for which the rate of occurrence was greater for patients treated with ARICEPT than with placebo. Table 4. Adverse Reactions in Pooled Controlled Clinical Trials in Severe Alzheimer’s Disease Body System/Adverse Reaction Placebo (n=392) %
ARICEPT
(n=501)
- Percent of Patients with any Adverse Reaction %
- Accident
- Infection
- Diarrhea
- Anorexia
- Vomiting
- Nausea
- Insomnia
- Ecchymosis
- Headache
- Hypertension
- Pain
- Back Pain
- Eczema
- Hallucinations
- Hostility
- Increase in Creatine Phosphokinase
- Nervousness
- Fever
- Chest Pain <1
- Confusion
- Dehydration
- Depression
- Dizziness
- Emotional Lability
- Hemorrhage
- Hyperlipemia <1
- Personality Disorder
- Somnolence
- Syncope
- Urinary Incontinence
Moderate to Severe Alzheimer’s Disease (ARICEPT 23 mg/day)
ARICEPT 23 mg/day has been administered to over 1300 individuals globally in clinical trials. Approximately 1050 of these patients have been treated for at least three months and more than 950 patients have been treated for at least six months. The range of patient exposure was from 1 to over 500 days.
Adverse Reactions Leading to Discontinuation
The rate of discontinuation from a controlled clinical trial of ARICEPT 23 mg/day due to adverse reactions was higher (19%) than for the 10 mg/day treatment group (8%). The most common adverse reactions leading to discontinuation, defined as those occurring in at least 1% of patients and greater than those occurring with 10 mg/day are shown in Table 5.
Table 5. Most Common Adverse Reactions Leading to Discontinuation in Patients with Moderate to Severe Alzheimer’s Disease
Adverse Reaction
23 mg/day ARICEPT (n=963) %
10 mg/day ARICEPT (n=471) % Vomiting 3 0 Diarrhea 2 0 Nausea 2 0 Dizziness 1 0
The majority of discontinuations due to adverse reactions in the 23 mg group occurred during the first month of treatment.
Most Common Adverse Reactions with ARICEPT 23 mg/day
The most common adverse reactions, defined as those occurring at a frequency of at least 5%, include nausea, diarrhea, vomiting, and anorexia.
Table 6 lists adverse reactions that occurred in at least 2% of patients who received 23 mg/day of ARICEPT and at a higher frequency than those receiving 10 mg/day of ARICEPT in a controlled clinical trial that compared the two doses. In this study, there were no important differences in the type of adverse reactions in patients taking ARICEPT with or without memantine.
Table 6. Adverse Reactions in a Controlled Clinical Trial in Moderate to Severe Alzheimer’s Disease Adverse Reaction 23 mg/day ARICEPT (n=963) %
10 mg/day ARICEPT (n=471) % Percent of Patients with any Adverse Reaction
Nausea 12 3 Vomiting 9 3
Data
Animal Data Oral administration of donepezil to pregnant rats and rabbits during the period of organogenesis did not produce any teratogenic effects at doses up to 16 mg/kg/day (approximately 6 times the maximum recommended human dose [MRHD] of 23 mg/day on a mg/m^2 basis) and 10 mg/kg/day (approximately 7 times the MRHD on a mg/m^2 basis), respectively. Oral administration of donepezil (1, 3, 10 mg/kg/day) to rats during late gestation and throughout lactation to weaning produced an increase in stillbirths and reduced offspring survival through postpartum day 4 at the highest dose. The no-effect dose of 3 mg/kg/day is approximately equal to the MRHD on a mg/m^2 basis.
8.2 Lactation
Risk Summary There are no data on the presence of donepezil or its metabolites in human milk, the effects on the breastfed infant, or on milk production.
The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for ARICEPT and any potential adverse effects on the breastfed infant from ARICEPT or from the underlying maternal condition.
8.4 Pediatric Use The safety and effectiveness in pediatric patients have not been established.
8.5 Geriatric Use Alzheimer’s disease is a disorder occurring primarily in individuals over 55 years of age. The mean age of patients enrolled in the clinical studies with ARICEPT was 73 years; 80% of these patients were between 65 and 84 years old, and 49% of patients were at or above the age of 75. The efficacy and safety data presented in the clinical trials section were obtained from these patients. There were no clinically significant differences in most adverse reactions reported by patient groups ≥ 65 years old and < 65 years old.
8.6 Lower Weight Individuals In the controlled clinical trial, among patients in the ARICEPT 23 mg treatment group, those patients weighing < 55 kg reported more nausea, vomiting, and decreased weight than patients weighing 55 kg or more. There were more withdrawals due to adverse reactions as well. This finding may be related to higher plasma exposure associated with lower weight.
10 OVERDOSAGE Because strategies for the management of overdose are continually evolving, it is advisable to contact a Poison Control Center to determine the latest recommendations for the management of an overdose of any drug.
As in any case of overdose, general supportive measures should be utilized. Overdosage with cholinesterase inhibitors can result in cholinergic crisis characterized by severe nausea, vomiting, salivation, sweating, bradycardia, hypotension, respiratory depression, collapse, and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved. Tertiary anticholinergics such as atropine may be used as an antidote for ARICEPT overdosage. Intravenous atropine sulfate titrated to effect is recommended: an initial dose of 1.0 to 2.0 mg IV with subsequent doses based upon clinical response. Atypical responses in blood pressure and heart rate have been reported with other cholinomimetics when co-administered
with quaternary anticholinergics such as glycopyrrolate. It is not known whether ARICEPT and/or its metabolites can be removed by dialysis (hemodialysis, peritoneal dialysis, or hemofiltration).
Dose-related signs of toxicity in animals included reduced spontaneous movement, prone position, staggering gait, lacrimation, clonic convulsions, depressed respiration, salivation, miosis, tremors, fasciculation, and lower body surface temperature.
11 DESCRIPTION
ARICEPT (donepezil hydrochloride) is a reversible inhibitor of the enzyme acetylcholinesterase, known chemically as (±)-2, 3-dihydro-5, 6-dimethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1 H -inden-1-one hydrochloride. Donepezil hydrochloride is commonly referred to in the pharmacological literature as E2020. It has an empirical formula of C 24 H 29 NO 3 HCl and a molecular weight of 415.96. Donepezil hydrochloride is a white crystalline powder and is freely soluble in chloroform, soluble in water and in glacial acetic acid, slightly soluble in ethanol and in acetonitrile, and practically insoluble in ethyl acetate and in n-hexane.
ARICEPT is available for oral administration in film-coated tablets containing 5, 10, or 23 mg of donepezil hydrochloride.
Inactive ingredients in 5 mg and 10 mg tablets are lactose monohydrate, corn starch, microcrystalline cellulose, hydroxypropyl cellulose, and magnesium stearate. The film coating contains talc, polyethylene glycol, hypromellose, and titanium dioxide. Additionally, the 10 mg tablet contains yellow iron oxide (synthetic) as a coloring agent.
Inactive ingredients in 23 mg tablets include ethylcellulose, hydroxypropyl cellulose, lactose monohydrate, magnesium stearate, and methacrylic acid copolymer, Type C. The film coating includes ferric oxide, hypromellose 2910, polyethylene glycol 8000, talc, and titanium dioxide.
ARICEPT ODT tablets are available for oral administration. Each ARICEPT ODT tablet contains 5 or 10 mg of donepezil hydrochloride. Inactive ingredients are carrageenan, mannitol, colloidal silicon dioxide, and polyvinyl alcohol. Additionally, the 10 mg tablet contains ferric oxide (yellow) as a coloring agent.
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Current theories on the pathogenesis of the cognitive signs and symptoms of Alzheimer’s disease attribute some of them to a deficiency of cholinergic neurotransmission.
Donepezil hydrochloride is postulated to exert its therapeutic effect by enhancing cholinergic function. This is accomplished by increasing the concentration of acetylcholine through reversible inhibition of its hydrolysis by acetylcholinesterase. There is no evidence that donepezil alters the course of the underlying dementing process.
12.3 Pharmacokinetics
analysis of plasma donepezil concentrations measured in patients with Alzheimer’s disease indicates that gender and race (Japanese and Caucasians) did not affect the clearance of ARICEPT to an important degree.
Body Weight There was a relationship noted between body weight and clearance. Over the range of body weight from 50 kg to 110 kg, clearance increased from 7.77 L/h to 14.04 L/h, with a value of 10 L/hr for 70 kg individuals.
Drug Interactions
Effect of ARICEPT on the Metabolism of Other Drugs No in vivo clinical trials have investigated the effect of ARICEPT on the clearance of drugs metabolized by CYP 3A4 (e.g., cisapride, terfenadine) or by CYP 2D6 (e.g., imipramine). However, in vitro studies show a low rate of binding to these enzymes (mean Ki about 50-130 μM), that, given the therapeutic plasma concentrations of donepezil (164 nM), indicates little likelihood of interference. Based on in vitro studies, donepezil shows little or no evidence of direct inhibition of CYP2B6, CYP2C8, and CYP2C19 at clinically relevant concentrations.
Whether ARICEPT has any potential for enzyme induction is not known. Formal pharmacokinetic studies evaluated the potential of ARICEPT for interaction with theophylline, cimetidine, warfarin, digoxin, and ketoconazole. No effects of ARICEPT on the pharmacokinetics of these drugs were observed.
Effect of Other Drugs on the Metabolism of ARICEPT Ketoconazole and quinidine, strong inhibitors of CYP450 3A and 2D6, respectively, inhibit donepezil metabolism in vitro. Whether there is a clinical effect of quinidine is not known. Population pharmacokinetic analysis showed that in the presence of concomitant CYP2D6 inhibitors donepezil AUC was increased by approximately 17% to 20% in Alzheimer’s disease patients taking ARICEPT 10 and 23 mg. This represented an average effect of weak, moderate, and strong CYP2D6 inhibitors. In a 7-day crossover study in 18 healthy volunteers, ketoconazole (200 mg q.d.) increased mean donepezil (5 mg q.d.) concentrations (AUC0-24 and Cmax) by 36%. The clinical relevance of this increase in concentration is unknown.
Inducers of CYP 3A (e.g., phenytoin, carbamazepine, dexamethasone, rifampin, and phenobarbital) could increase the rate of elimination of ARICEPT.
Formal pharmacokinetic studies demonstrated that the metabolism of ARICEPT is not significantly affected by concurrent administration of digoxin or cimetidine.
An in vitro study showed that donepezil was not a substrate of P-glycoprotein.
Drugs Highly Bound to Plasma Proteins Drug displacement studies have been performed in vitro between this highly bound drug (96%) and other drugs such as furosemide, digoxin, and warfarin. ARICEPT at concentrations of 0.3-10 micrograms/mL did not affect the binding of furosemide (5 micrograms/mL), digoxin (2 ng/mL), and warfarin (3 micrograms/mL) to human albumin. Similarly, the binding of ARICEPT to human albumin was not affected by furosemide, digoxin, and warfarin.
13 NONCLINICAL TOXICOLOGY 13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility No evidence of carcinogenic potential was obtained in an 88-week carcinogenicity study of donepezil conducted in mice at oral doses up to 180 mg/kg/day (approximately 40 times the maximum recommended
human dose [MRHD] of 23 mg/day on a mg/m^2 basis), or in a 104-week carcinogenicity study in rats at oral doses up to 30 mg/kg/day (approximately 13 times the MRHD on a mg/m^2 basis).
Donepezil was negative in a battery of genotoxicity assays ( in vitro bacterial reverse mutation, in vitro mouse lymphoma tk , in vitro chromosomal aberration, and in vivo mouse micronucleus).
Donepezil had no effect on fertility in rats at oral doses up to 10 mg/kg/day (approximately 4 times the MRHD on a mg/m^2 basis) when administered to males and females prior to and during mating and continuing in females through implantation.
13.2 Animal Toxicology and/or Pharmacology In an acute dose neurotoxicity study in female rats, oral administration of donepezil and memantine in combination resulted in increased incidence, severity, and distribution of neurodegeneration compared with memantine alone. The no-effect levels of the combination were associated with clinically relevant plasma donepezil and memantine levels.
The relevance of this finding to humans is unknown.
14 CLINICAL STUDIES
14.1 Mild to Moderate Alzheimer’s Disease The effectiveness of ARICEPT as a treatment for mild to moderate Alzheimer’s disease is demonstrated by the results of two randomized, double-blind, placebo-controlled clinical investigations in patients with Alzheimer’s disease (diagnosed by NINCDS and DSM III-R criteria, Mini-Mental State Examination ≥ 10 and ≤ 26 and Clinical Dementia Rating of 1 or 2). The mean age of patients participating in ARICEPT trials was 73 years with a range of 50 to 94. Approximately 62% of patients were women and 38% were men. The racial distribution was white 95%, black 3%, and other races 2%.
The higher dose of 10 mg did not provide a statistically significantly greater clinical benefit than 5 mg. There is a suggestion, however, based upon order of group mean scores and dose trend analyses of data from these clinical trials, that a daily dose of 10 mg of ARICEPT might provide additional benefit for some patients. Accordingly, whether or not to employ a dose of 10 mg is a matter of prescriber and patient preference.
Study Outcome Measures In each study, the effectiveness of treatment with ARICEPT was evaluated using a dual outcome assessment strategy.
The ability of ARICEPT to improve cognitive performance was assessed with the cognitive subscale of the Alzheimer’s Disease Assessment Scale (ADAS-cog), a multi-item instrument that has been extensively validated in longitudinal cohorts of Alzheimer’s disease patients. The ADAS-cog examines selected aspects of cognitive performance including elements of memory, orientation, attention, reasoning, language, and praxis. The ADAS-cog scoring range is from 0 to 70, with higher scores indicating greater cognitive impairment. Elderly normal adults may score as low as 0 or 1, but it is not unusual for non-demented adults to score slightly higher.
The patients recruited as participants in each study had mean scores on the ADAS-cog of approximately 26 points, with a range from 4 to 61. Experience based on longitudinal studies of ambulatory patients with mild to moderate Alzheimer’s disease suggest that scores on the ADAS-cog increase (worsen) by 6-12 points per year. However, smaller changes may be seen in patients with very mild or very advanced disease since the ADAS-cog is not uniformly sensitive to change over the course of the disease. The annualized rate of decline in the placebo patients participating in ARICEPT trials was approximately 2 to 4 points per year.
Weeks of Drug Treatment Placebo
0 6 12 18 24 30
Mean (±SE)
ADAS-cog Change from Baseline
**- 3
Placebo Aricept 5 mg/day^ Aricept 10 mg/day
Improvement^ Clinical
ClinicalDecline
Baseline
Weeks of Drug Treatment Placebo
0 6 12 18 24 30
Mean (±SE)
ADAS-cog Change from Baseline
**- 3
Placebo Aricept 5 mg/day^ Aricept 10 mg/day
Improvement^ Clinical
ClinicalDecline
Baseline
Figure 2 illustrates the cumulative percentages of patients from each of the three treatment groups who had attained the measure of improvement in ADAS-cog score shown on the X axis. Three change scores (7-point and 4-point reductions from baseline or no change in score) have been identified for illustrative purposes, and the percent of patients in each group achieving that result is shown in the inset table.
The curves demonstrate that both patients assigned to placebo and ARICEPT have a wide range of responses, but that the active treatment groups are more likely to show greater improvements. A curve for an effective treatment would be shifted to the left of the curve for placebo, while an ineffective or deleterious treatment would be superimposed upon or shifted to the right of the curve for placebo.
Figure 2. Cumulative Percentage of Patients Completing 24 Weeks of Double-blind Treatment with Specified Changes from Baseline ADAS-cog Scores. The Percentages of Randomized Patients who Completed the Study were: Placebo 80%, 5 mg/day 85%, and 10 mg/day 68%.
Placebo Aricept 5 mg/day Aricept 10 mg/day Placebo Aricept 5 mg/day Aricept 10 mg/day Placebo Aricept 5 mg/day Aricept 10 mg/day
Effects on the CIBIC-plus Figure 3 is a histogram of the frequency distribution of CIBIC-plus scores attained by patients assigned to each of the three treatment groups who completed 24 weeks of treatment. The mean drug-placebo differences for these groups of patients were 0.35 points and 0.39 points for 5 mg/day and 10 mg/day of ARICEPT, respectively. These differences were statistically significant. There was no statistically significant difference between the two active treatments.
Figure 3. Frequency Distribution of CIBIC-plus Scores at Week 24.
CIBIC-plus Rating
Percentage of Patients
0
10
20
30
40
50
MarkedlyImprovedModeratelyImproved MinimallyImproved ChangeNo MinimallyWorse ModeratelyWorse MarkedlyWorse
Placebo
Aricept 5 mg/day Aricept 10 mg/day
CIBIC-plus Rating
Percentage of Patients
0
10
20
30
40
50
MarkedlyImprovedModeratelyImproved MinimallyImproved ChangeNo MinimallyWorse ModeratelyWorse MarkedlyWorse
Placebo
Aricept 5 mg/day Aricept 10 mg/day
Fifteen-Week Study
In a study of 15 weeks duration, patients were randomized to receive single daily doses of placebo or either 5 mg/day or 10 mg/day of ARICEPT for 12 weeks, followed by a 3-week placebo washout period. As in the 30-week study, to avoid acute cholinergic effects, the 10 mg/day treatment followed an initial 7-day treatment with 5 mg/day doses.
Effects on the ADAS-cog Figure 4 illustrates the time course of the change from baseline in ADAS-cog scores for all three dose groups over the 15 weeks of the study. After 12 weeks of treatment, the differences in mean ADAS-cog change scores for the ARICEPT treated patients compared to the patients on placebo were 2.7 and 3.0 points each, for the 5 and 10 mg/day ARICEPT treatment groups, respectively. These differences were statistically significant. The effect size for the 10 mg/day group may appear to be slightly larger than that for 5 mg/day. However, the differences between active treatments were not statistically significant.
Figure 4. Time-course of the Change from Baseline in ADAS-cog Score for Patients Completing the 15-week Study.
0 3 6 9 12 15
**- 4
- 3
- 2
- 1** 0 1 2 3 Weeks of Drug Treatment Placebo
Mean (±SE)
ADAS-cog Change from Baseline
(^) Clinical Improvement
ClinicalDecline
Baseline
Placebo Aricept 5 mg/day^ Aricept 10 mg/day
0 3 6 9 12 15
**- 4
- 3
- 2
- 1** 0 1 2 3 Weeks of Drug Treatment Placebo
Mean (±SE)
ADAS-cog Change from Baseline
(^) Clinical Improvement
ClinicalDecline
Baseline
Placebo Aricept 5 mg/day^ Aricept 10 mg/day
Following 3 weeks of placebo washout, scores on the ADAS-cog for both the ARICEPT treatment groups increased, indicating that discontinuation of ARICEPT resulted in a loss of its treatment effect. The duration of this placebo washout period was not sufficient to characterize the rate of loss of the treatment effect, but the 30- week study (see above) demonstrated that treatment effects associated with the use of ARICEPT abate within 6 weeks of treatment discontinuation.
14.2 Moderate to Severe Alzheimer’s Disease
The effectiveness of ARICEPT in the treatment of patients with moderate to severe Alzheimer’s disease was established in studies employing doses of 10 mg/day and 23 mg/day. Results of a controlled clinical trial in moderate to severe Alzheimer’s Disease that compared ARICEPT 23 mg once daily to 10 mg once daily suggest that a 23 mg dose of ARICEPT provided additional benefit.
Swedish 6 Month Study (10 mg/day)
The effectiveness of ARICEPT as a treatment for severe Alzheimer’s disease is demonstrated by the results of a randomized, double-blind, placebo-controlled clinical study conducted in Sweden (6 month study) in patients with probable or possible Alzheimer’s disease diagnosed by NINCDS-ADRDA and DSM-IV criteria, MMSE: range of 1-10. Two hundred and forty eight (248) patients with severe Alzheimer’s disease were randomized to ARICEPT or placebo. For patients randomized to ARICEPT, treatment was initiated at 5 mg once daily for 28 days and then increased to 10 mg once daily. At the end of the 6 month treatment period, 90.5% of the ARICEPT treated patients were receiving the 10 mg/day dose. The mean age of patients was 84.9 years, with a range of 59 to 99. Approximately 77% of patients were women, and 23% were men. Almost all patients were Caucasian. Probable Alzheimer’s disease was diagnosed in the majority of the patients (83.6% of ARICEPT treated patients and 84.2% of placebo treated patients).
Study Outcome Measures The effectiveness of treatment with ARICEPT was determined using a dual outcome assessment strategy that evaluated cognitive function using an instrument designed for more impaired patients and overall function through caregiver-rated assessment. This study showed that patients on ARICEPT experienced significant improvement on both measures compared to placebo.
The ability of ARICEPT to improve cognitive performance was assessed with the Severe Impairment Battery (SIB). The SIB, a multi-item instrument, has been validated for the evaluation of cognitive function in patients with moderate to severe dementia. The SIB evaluates selective aspects of cognitive performance, including elements of memory, language, orientation, attention, praxis, visuospatial ability, construction, and social interaction. The SIB scoring range is from 0 to 100, with lower scores indicating greater cognitive impairment.
Daily function was assessed using the Modified Alzheimer’s Disease Cooperative Study Activities of Daily Living Inventory for Severe Alzheimer’s Disease (ADCS-ADL-severe). The ADCS-ADL-severe is derived from the Alzheimer’s Disease Cooperative Study Activities of Daily Living Inventory, which is a comprehensive battery of ADL questions used to measure the functional capabilities of patients. Each ADL item is rated from the highest level of independent performance to complete loss. The ADCS-ADL-severe is a subset of 19 items, including ratings of the patient’s ability to eat, dress, bathe, use the telephone, get around (or travel), and perform other activities of daily living; it has been validated for the assessment of patients with moderate to severe dementia. The ADCS-ADL-severe has a scoring range of 0 to 54, with the lower scores indicating greater functional impairment. The investigator performs the inventory by interviewing a caregiver, in this study a nurse staff member, familiar with the functioning of the patient.
Effects on the SIB Figure 7 shows the time course for the change from baseline in SIB score for the two treatment groups over the 6 months of the study. At 6 months of treatment, the mean difference in the SIB change scores for ARICEPT treated patients compared to patients on placebo was 5.9 points. ARICEPT treatment was statistically significantly superior to placebo.
Figure 7. Time Course of the Change from Baseline in SIB Score for Patients Completing 6 Months of Treatment.
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Figure 8 illustrates the cumulative percentages of patients from each of the two treatment groups who attained the measure of improvement in SIB score shown on the X-axis. While patients assigned both to ARICEPT and to placebo have a wide range of responses, the curves show that the ARICEPT group is more likely to show a greater improvement in cognitive performance.
Figure 8. Cumulative Percentage of Patients Completing 6 Months of Double-blind Treatment with Particular Changes from Baseline in SIB Scores.
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Figure 9. Time Course of the Change from Baseline in ADCS-ADL-Severe Score for Patients Completing 6 Months of Treatment.
