ADVERSE REACTIONS SECTION.


6 ADVERSE REACTIONS. Most common adverse reactions in clinical studies of donepezil hydrochloride tablets are nausea, diarrhea, insomnia, vomiting, muscle cramps, fatigue, and anorexia (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Torrent Pharma Inc. at 1-800-912-9561 or FDA at 1-800-FDA-1088, or www.fda.gov/medwatch.. The following serious adverse reactions are described below and elsewhere in the labeling:oCardiovascular Conditions [see Warnings and Precautions (5.2)] oNausea and Vomiting [see Warnings and Precautions (5.3)] oPeptic Ulcer Disease and GI Bleeding [see Warnings and Precautions (5.4)] oGenitourinary Conditions [see Warnings and Precautions (5.6)] oNeurological Conditions: Seizures [see Warnings and Precautions (5.7)] oPulmonary Conditions [see Warnings and Precautions (5.8)]. oCardiovascular Conditions [see Warnings and Precautions (5.2)] oNausea and Vomiting [see Warnings and Precautions (5.3)] oPeptic Ulcer Disease and GI Bleeding [see Warnings and Precautions (5.4)] oGenitourinary Conditions [see Warnings and Precautions (5.6)] oNeurological Conditions: Seizures [see Warnings and Precautions (5.7)] oPulmonary 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 drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Donepezil hydrochloride tablets have been administered to over 1,700 individuals during clinical trials worldwide. Approximately 1,200 of these patients have been treated for at least months and more than 1,000 patients have been treated for at least 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 months, 475 patients treated for months, and 116 patients treated for over year. The range of patient exposure is from to 1,214 daysMild to Moderate Alzheimers Disease Adverse Reactions Leading to Discontinuation The rates of discontinuation from controlled clinical trials of donepezil hydrochloride tablets due to adverse reactions for the donepezil hydrochloride tablets 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 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 Alzheimers Disease Adverse ReactionPlacebo(n=355)%5 mg/dayDonepezil Hydrochloride Tablets(n=350)%10 mg/day Donepezil Hydrochloride Tablets(n=315)%Nausea 1 Diarrhea <1 Vomiting <1 <1 Most Common Adverse ReactionsThe most common adverse reactions, defined as those occurring at frequency of at least 5% in patients receiving 10 mg/day and twice the placebo rate, are largely predicted by donepezil hydrochloride tablets cholinomimetic effects. These include nausea, diarrhea, insomnia, vomiting, muscle cramp, fatigue and anorexia. These adverse events were often transient, resolving during continued donepezil hydrochloride tablets 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 dose of 10 mg/day over 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 mg/day. See Table for 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 and 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 5 19 Diarrhea 8 15 Insomnia 6 14 Fatigue 4 3 Vomiting 3 5 Muscle cramps 6 3 Anorexia 3 3 Table lists adverse reactions that occurred in at least 2% of patients in pooled placebo-controlled trials who received either donepezil hydrochloride tablets mg or 10 mg and for which the rate of occurrence was greater for patients treated with donepezil hydrochloride tablets 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 Alzheimers Disease Adverse ReactionPlacebo(n=355)%Donepezil Hydrochloride Tablets(n=747)%Percent of Patients with any Adverse Reaction 7274Nausea 11 Diarrhea 10 Headache 10 Insomnia 9 Pain, various locations 9 Dizziness 8 Accident 7 Muscle Cramps 6 Fatigue 5 Vomiting 5 Anorexia 4 Ecchymosis 4 Abnormal Dreams 3 Depression <1 Weight Loss 3 Arthritis 2 Frequent Urination 2 Somnolence <1 Syncope 2 Severe Alzheimers Disease (Donepezil hydrochloride tablets mg/day and 10 mg/day)Donepezil hydrochloride tablets has been administered to over 600 patients with severe Alzheimers disease during clinical trials of at least months duration, including three double-blind, placebo-controlled trials, two of which had an open label extension.Adverse Reactions Leading to Discontinuation The rates of discontinuation from controlled clinical trials of donepezil hydrochloride tablets due to adverse reactions for the donepezil hydrochloride tablets patients were approximately 12% compared to 7% for placebo patients. The most common adverse reactions leading to discontinuation, defined as those occurring in at least 2% of donepezil hydrochloride tablets patients and at twice or more the incidence seen in placebo, were anorexia (2% vs. 1% placebo), nausea (2% vs. <1% placebo), diarrhea (2% vs. 0% placebo) and urinary tract infection (2% vs. 1% placebo). Most Common Adverse Reactions The most common adverse reactions, defined as those occurring at frequency of at least 5% in patients receiving donepezil hydrochloride tablets and at twice or more the placebo rate, are largely predicted by donepezil hydrochloride tablets cholinomimetic effects. These include diarrhea, anorexia, vomiting, nausea, and ecchymosis. These adverse reactions were often transient, resolving during continued donepezil hydrochloride tablets treatment without the need for dose modification. Table lists adverse reactions that occurred in at least 2% of patients in pooled placebo-controlled trials who received donepezil hydrochloride tablets mg and 10 mg and for which the rate of occurrence was greater for patients treated with donepezil hydrochloride tablets than with placebo.Table 4. Adverse Reactions in Pooled Controlled Clinical Trials in Severe Alzheimers Disease Body System/Adverse Reaction Placebo(n=392)%Donepezil Hydrochloride Tablets(n=501)% Percent of Patients with any Adverse Reaction 73 81 Accident 12 13 Infection 11 Diarrhea 10 Anorexia 8 Vomiting 8 Nausea 6 Insomnia 5 Ecchymosis 5 Headache 4 Hypertension 3 Pain 3 Back Pain 3 Eczema 3 Hallucinations 3 Hostility 3 Increase in Creatine Phosphokinase 3 Nervousness 3 Fever 2 Chest Pain <1 Confusion 2 Dehydration 2 Depression 2 Dizziness 2 Emotional Lability 2 Hemorrhage 2 Hyperlipemia <1 Personality Disorder 2 Somnolence 2 Syncope 2 Urinary Incontinence 2 6.2 Postmarketing Experience. The following adverse reactions have been identified during post-approval use of donepezil hydrochloride tablets. Because these reactions are reported voluntarily from population of uncertain size, it is not always possible to reliably estimate their frequency or establish causal relationship to drug exposure. Abdominal pain, agitation, aggression, cholecystitis, confusion, convulsions, hallucinations, heart block (all types), hemolytic anemia, hepatitis, hyponatremia, neuroleptic malignant syndrome, pancreatitis, rash, rhabdomyolysis, QTc prolongation, and torsade de pointes.

ANIMAL PHARMACOLOGY & OR TOXICOLOGY SECTION.


13.2 Animal Toxicology andor 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.

INDICATIONS & USAGE SECTION.


1 INDICATIONS AND USAGE. Donepezil hydrochloride tablets, USP are an acetylcholinesterase inhibitor indicated for the treatment of dementia of the Alzheimers type. Efficacy has been demonstrated in patients with mild, moderate, and severe Alzheimers Disease (1). Donepezil hydrochloride tablets, USP are indicated for the treatment of dementia of the Alzheimers type. Efficacy has been demonstrated in patients with mild, moderate, and severe Alzheimers disease.

INFORMATION FOR PATIENTS SECTION.


17 PATIENT COUNSELING INFORMATION. Advise the patient to read the FDA-approved patient labeling (Patient Information).Instruct patients and caregivers to take donepezil hydrochloride tablets only once per day, as prescribed.Instruct patients and caregivers that donepezil hydrochloride tablets can be taken with or without food.Advise patients and caregivers that donepezil hydrochloride tablets may cause nausea, diarrhea, insomnia, vomiting, muscle cramps, fatigue, and decreased appetite.Advise patients to notify their healthcare provider if they are pregnant or plan to become pregnant.Manufactured by:TORRENT PHARMACEUTICALS LTD., INDIA.Manufactured for:TORRENT PHARMA INC., Basking Ridge, NJ 07920.Distributed By:MAJOR(R) PHARMACEUTICALS17177 Laurel Park Dr., Suite 233Livonia, MI 481528073530 Revised January 2019. DONEPEZIL HYDROCHLORIDE TABLETS PATIENT PACKAGE INSERT Donepezil Hydrochloride (doe-NEP-e-zil HYE-droe-KLOR-ide) Tablets, USPRx OnlyoTablets: mg and 10 mg Read this Patient Information that comes with donepezil hydrochloride tablets before you start taking it and each time you get refill. There may be new information. This leaflet does not take the place of talking with your doctor about Alzheimers disease or treatment for it. If you have questions, ask the doctor or pharmacist. What are donepezil hydrochloride tablets Donepezil hydrochloride tablets come as donepezil hydrochloride film-coated tablets in dosage strengths of mg and 10 mg.Donepezil hydrochloride tablets are prescription medicine to treat mild, moderate and severe Alzheimers disease. Donepezil hydrochloride tablets can help with mental function and with doing daily tasks. Donepezil hydrochloride tablet does not work the same in all people. Some people may: oSeem much better oGet better in small ways or stay the same oGet worse over time but slower than expected oNot change and then get worse as expected Donepezil hydrochloride tablet does not cure Alzheimers disease. All patients with Alzheimers disease get worse over time, even if they take donepezil hydrochloride tablets. Donepezil hydrochloride tablets have not been approved as treatment for any medical condition in children. Who should not take donepezil hydrochloride tablets Do not take donepezil hydrochloride tablets if you are allergic to any of the ingredients in donepezil hydrochloride tablets or to medicines that contain piperidines. Ask your doctor if you are not sure. See the end of this leaflet for list of ingredients in donepezil hydrochloride tablets. What should tell my doctor before taking donepezil hydrochloride tablets Tell the doctor about all of your present or past health problems and conditions. Include: Any heart problems including problems with irregular, slow, or fast heartbeats Asthma or lung problems seizure Stomach ulcers Difficulty passing urine Liver or kidney problems Trouble swallowing tablets Present pregnancy or plans to become pregnant. It is not known if donepezil hydrochloride tablets can harm an unborn baby. oPresent breast-feeding. It is not known if donepezil hydrochloride passes into breast milk. Talk to your doctor about the best way to feed your baby if you take Donepezil hydrochloride tablets.Tell the doctor about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal products. Donepezil hydrochloride tablets and other medicines may affect each other. Be particularly sure to tell the doctor if you take aspirin or medicines called nonsteroidal anti-inflammatory drugs (NSAIDs). There are many NSAID medicines, both prescription and non-prescription. Ask the doctor or pharmacist if you are not sure if any of your medicines are NSAIDs. Taking NSAIDs and donepezil hydrochloride tablets together may make you more likely to get stomach ulcers.Donepezil hydrochloride tablets taken with certain medicines used for anesthesia may cause side effects. Tell the responsible doctor or dentist that you take donepezil hydrochloride tablets before you have: osurgery omedical procedures odental surgery or procedures. Know the medicines that you take. Keep list of all your medicines. Show it to your doctor or pharmacist before you start new medicine. How should you take donepezil hydrochloride tablets Take donepezil hydrochloride tablets exactly as prescribed by the doctor. Do not stop donepezil hydrochloride tablets or change the dose yourself. Talk with your doctor first.o Take donepezil hydrochloride tablets one time each day. Donepezil hydrochloride tablets can be taken with or without food.o If you miss dose of donepezil hydrochloride tablets, just wait. Take only the next dose at the usual time. Do not take doses at the same time.o If donepezil hydrochloride tablets are missed for days or more, talk with your doctor before starting again.o If you take too much donepezil hydrochloride tablets at one time, call your doctor or poison control center, or go to the emergency room right away.What are the possible side effects of donepezil hydrochloride tablets Donepezil hydrochloride tablets may cause the following serious side effects:o slow heartbeat and fainting. This happens more often in people with heart problems. Call your doctor right away if you feel faint or lightheaded while taking donepezil hydrochloride tablets.o more stomach acid. This raises the chance of ulcers and bleeding. The risk is higher for patients who have had ulcers, or take aspirin or other NSAIDs.o worsening of lung problems in people with asthma or other lung disease.o seizures.o difficulty passing urine.Call your doctor right away if you have: ofainting. oheartburn or stomach pain that is new or wont go away. onausea or vomiting, blood in the vomit, dark vomit that looks like coffee grounds. obowel movements or stools that look like black tar. onew or worse asthma or breathing problems. oseizures. odifficulty passing urine. The most common side effects of donepezil hydrochloride tablets are: onausea odiarrhea onot sleeping well ovomiting omuscle cramps ofeeling tired onot wanting to eat These side effects may get better after you take donepezil hydrochloride tablets for while. This is not complete list of side effects with donepezil hydrochloride tablets. For more information, ask your doctor or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. How should donepezil hydrochloride tablets be stored Store donepezil hydrochloride tablets at 20 to 25C (68 to 77F); excursions permitted to 15 to 30C (59 to 86F). [see USP Controlled Room Temperature]. Keep donepezil hydrochloride tablets and all medicines out of the reach of children. General information about donepezil hydrochloride tablets Medicines are sometimes prescribed for conditions that are not mentioned in this Patient Information Leaflet. Do not use donepezil hydrochloride tablets for condition for which it was not prescribed. Do not give donepezil hydrochloride tablets to other people, even if they have the same symptoms or condition. It may harm them.This leaflet summarizes the most important information about donepezil hydrochloride tablets. If you would like more information, talk with your doctor. You can ask your pharmacist or doctor for information about donepezil hydrochloride tablets that is written for health professionals. For more information, call 1-800-912-9561.What are the ingredients in donepezil hydrochloride tablets Active ingredient: donepezil hydrochloride, USPInactive ingredients: Donepezil hydrochloride5 mg and 10 mg film-coated tablets: lactose monohydrate, magnesium stearate, maize starch (Zea mays and microcrystalline cellulose. The film coating contains hypromellose, polyethylene glycol, talc and titanium dioxide. Additionally, the 10 mg tablet contains ferric oxide red and ferric oxide yellow as coloring agents.This Medication Guide has been approved by the US Food and Drug Administration.Manufactured by:TORRENT PHARMACEUTICALS LTD., INDIA.Manufactured for:TORRENT PHARMA INC., Basking Ridge, NJ 07920.Distributed By:MAJOR(R) PHARMACEUTICALS17177 Laurel Park Dr., Suite 233Livonia, MI 481528073531 Revised January 2019. oTablets: mg and 10 mg oSeem much better oGet better in small ways or stay the same oGet worse over time but slower than expected oNot change and then get worse as expected oPresent breast-feeding. It is not known if donepezil hydrochloride passes into breast milk. Talk to your doctor about the best way to feed your baby if you take Donepezil hydrochloride tablets.. osurgery omedical procedures odental surgery or procedures. o Take donepezil hydrochloride tablets exactly as prescribed by the doctor. Do not stop donepezil hydrochloride tablets or change the dose yourself. Talk with your doctor first.. Take donepezil hydrochloride tablets one time each day. Donepezil hydrochloride tablets can be taken with or without food.. If you miss dose of donepezil hydrochloride tablets, just wait. Take only the next dose at the usual time. Do not take doses at the same time.. If donepezil hydrochloride tablets are missed for days or more, talk with your doctor before starting again.. If you take too much donepezil hydrochloride tablets at one time, call your doctor or poison control center, or go to the emergency room right away.. slow heartbeat and fainting. This happens more often in people with heart problems. Call your doctor right away if you feel faint or lightheaded while taking donepezil hydrochloride tablets.. more stomach acid. This raises the chance of ulcers and bleeding. The risk is higher for patients who have had ulcers, or take aspirin or other NSAIDs.. worsening of lung problems in people with asthma or other lung disease.. seizures.. difficulty passing urine.. ofainting. oheartburn or stomach pain that is new or wont go away. onausea or vomiting, blood in the vomit, dark vomit that looks like coffee grounds. obowel movements or stools that look like black tar. onew or worse asthma or breathing problems. oseizures. odifficulty passing urine. onausea odiarrhea onot sleeping well ovomiting omuscle cramps ofeeling tired onot wanting to eat o Donepezil hydrochloride5 mg and 10 mg film-coated tablets: lactose monohydrate, magnesium stearate, maize starch (Zea mays and microcrystalline cellulose. The film coating contains hypromellose, polyethylene glycol, talc and titanium dioxide. Additionally, the 10 mg tablet contains ferric oxide red and ferric oxide yellow as coloring agents.. logo. logo.

CARCINOGENESIS & MUTAGENESIS & IMPAIRMENT OF FERTILITY SECTION.


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 86 times the maximum recommended human dose [MRHD] of 10 mg/day on mg/m2 basis), or in 104-week carcinogenicity study in rats at oral doses up to 30 mg/kg/day (approximately 29 times the MRHD on mg/m2 basis).Donepezil was negative in 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 10 times the MRHD on mg/m2 basis) when administered to males and females prior to and during mating and continuing in females through implantation.

CLINICAL PHARMACOLOGY SECTION.


12 CLINICAL PHARMACOLOGY. 12.1 Mechanism of Action. Current theories on the pathogenesis of the cognitive signs and symptoms of Alzheimers disease attribute some of them to 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. Pharmacokinetics of donepezil are linear over dose range of to 10 mg given once daily. The rate and extent of absorption of donepezil hydrochloride tablets are not influenced by food. Donepezil hydrochloride ODT mg and 10 mg are bioequivalent to donepezil hydrochloride mg and 10 mg tablets, respectively. The elimination half life of donepezil is about 70 hours, and the mean apparent plasma clearance (Cl/F) is 0.13 to 0.19 L/hr/kg. Following multiple dose administration, donepezil accumulates in plasma by to fold, and steady state is reached within 15 days. The steady state volume of distribution is 12 to 16 L/kg. Donepezil is approximately 96% bound to human plasma proteins, mainly to albumins (about 75%) and alpha1 acid glycoprotein (about 21%) over the concentration range of to 1000 ng/mL. Donepezil is both excreted in the urine intact and extensively metabolized to four major metabolites, two of which are known to be active, and number of minor metabolites, not all of which have been identified. Donepezil is metabolized by CYP 450 isoenzymes 2D6 and 3A4 and undergoes glucuronidation. Following administration of 14C-labeled donepezil, plasma radioactivity, expressed as percent of the administered dose, was present primarily as intact donepezil (53%) and as 6-O-desmethyl donepezil (11%), which has been reported to inhibit AChE to the same extent as donepezil in vitro and was found in plasma at concentrations equal to about 20% of donepezil. Approximately 57% and 15% of the total radioactivity was recovered in urine and feces, respectively, over period of 10 days, while 28% remained unrecovered, with about 17% of the donepezil dose recovered in the urine as unchanged drug. Examination of the effect of CYP2D6 genotype in Alzheimers patients showed differences in clearance values among CYP2D6 genotype subgroups. When compared to the extensive metabolizers, poor metabolizers had 31.5% slower clearance and ultra-rapid metabolizers had 24% faster clearance. Hepatic Disease In study of 10 patients with stable alcoholic cirrhosis, the clearance of donepezil hydrochloride was decreased by 20% relative to 10 healthy age- and sex-matched subjects. Renal DiseaseIn study of 11 patients with moderate to severe renal impairment (ClC 18 mL/min/1.73 m2) the clearance of donepezil hydrochloride did not differ from 11 age- and sex-matched healthy subjects. Age No formal pharmacokinetic study was conducted to examine age-related differences in the pharmacokinetics of donepezil hydrochloride. Population pharmacokinetic analysis suggested that the clearance of donepezil in patients decreases with increasing age. When compared with 65-year old subjects, 90-year old subjects have 17% decrease in clearance, while 40-year old subjects have 33% increase in clearance. The effect of age on donepezil clearance may not be clinically significant. Gender and Race No specific pharmacokinetic study was conducted to investigate the effects of gender and race on the disposition of donepezil hydrochloride. However, retrospective pharmacokinetic analysis and population pharmacokinetic analysis of plasma donepezil concentrations measured in patients with Alzheimers disease indicates that gender and race (Japanese and Caucasians) did not affect the clearance of donepezil hydrochloride to an important degree. Body weight There was 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 value of 10 L/hr for 70 kg individuals.Drug Interactions Effect of Donepezil Hydrochloride Tablets on the Metabolism of Other Drugs No in vivo clinical trials have investigated the effect of donepezil hydrochloride tablets 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 low rate of binding to these enzymes (mean Ki about 50 to 130 uM), 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 donepezil hydrochloride tablets have any potential for enzyme induction is not known. Formal pharmacokinetic studies evaluated the potential of donepezil hydrochloride tablets for interaction with theophylline, cimetidine, warfarin, digoxin and ketoconazole. No effects of donepezil hydrochloride tablets on the pharmacokinetics of these drugs were observed.Effect of Other Drugs on the Metabolism of Donepezil Hydrochloride TabletsKetoconazole and quinidine, strong inhibitors of CYP450 3A and 2D6, respectively, inhibit donepezil metabolism in vitro. Whether there is 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 Alzheimers disease patients taking donepezil hydrochloride tablets 10 mg. This represented an average effect of weak, moderate, and strong CYP2D6 inhibitors. In 7-day crossover study in 18 healthy volunteers, ketoconazole (200 mg q.d.) increased mean donepezil (5 mg q.d.) concentrations (AUC0 to 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 donepezil hydrochloride tablets.Formal pharmacokinetic studies demonstrated that the metabolism of donepezil hydrochloride tablets is not significantly affected by concurrent administration of digoxin or cimetidine.An in vitro study showed that donepezil was not substrate of P-glycoprotein.Drugs Highly Bound to Plasma ProteinsDrug displacement studies have been performed in vitro between this highly bound drug (96%) and other drugs such as furosemide, digoxin, and warfarin. Donepezil hydrochloride at concentrations of 0.3 to 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 donepezil hydrochloride to human albumin was not affected by furosemide, digoxin and warfarin.

CLINICAL STUDIES SECTION.


14 CLINICAL STUDIES. 14.1 Mild to Moderate Alzheimers Disease. The effectiveness of donepezil hydrochloride tablets as treatment for mild to moderate Alzheimers disease is demonstrated by the results of two randomized, double-blind, placebo-controlled clinical investigations in patients with Alzheimers disease (diagnosed by NINCDS and DSM III-R criteria, Mini-Mental State Examination >= 10 and <= 26 and Clinical Dementia Rating of or 2). The mean age of patients participating in donepezil hydrochloride tablets trials was 73 years with 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 statistically significantly greater clinical benefit than mg. There is suggestion, however, based upon order of group mean scores and dose trend analyses of data from these clinical trials, that daily dose of 10 mg of donepezil hydrochloride tablets might provide additional benefit for some patients. Accordingly, whether or not to employ dose of 10 mg is matter of prescriber and patient preference.Study Outcome Measures In each study, the effectiveness of treatment with donepezil hydrochloride tablets was evaluated using dual outcome assessment strategy. The ability of donepezil hydrochloride tablets to improve cognitive performance was assessed with the cognitive subscale of the Alzheimers Disease Assessment Scale (ADAS-cog), multi-text instrument that has been extensively validated in longitudinal cohorts of Alzheimers 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 to 70, with higher scores indicating greater cognitive impairment. Elderly normal adults may score as low as 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 range from to 61. Experience based on longitudinal studies of ambulatory patients with mild to moderate Alzheimers disease suggest that scores on the ADAS-cog increase (worsen) by to 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 donepezil hydrochloride tablets trials was approximately to points per year. The ability of donepezil hydrochloride tablets to produce an overall clinical effect was assessed using Clinicians Interview-Based Impression of Change that required the use of caregiver information, the CIBIC-plus. The CIBIC-plus is not single instrument and is not standardized instrument like the ADAS-cog. Clinical trials for investigational drugs have used variety of CIBIC formats, each different in terms of depth and structure. As such, results from CIBIC-plus reflect clinical experience from the trial or trials in which it was used and cannot be compared directly with the results of CIBIC-plus evaluations from other clinical trials. The CIBIC-plus used in donepezil hydrochloride tablets trials was semi-structured instrument that was intended to examine four major areas of patient function: General, Cognitive, Behavioral and Activities of Daily Living. It represents the assessment of skilled clinician based upon his/her observations at an interview with the patient, in combination with information supplied by caregiver familiar with the behavior of the patient over the interval rated. The CIBIC-plus is scored as seven-point categorical rating, ranging from score of 1, indicating markedly improved, to score of 4, indicating no change to score of 7, indicating markedly worse. The CIBIC-plus has not been systematically compared directly to assessments not using information from caregivers (CIBIC) or other global methods. Thirty-Week Study In study of 30 weeks duration, 473 patients were randomized to receive single daily doses of placebo, mg/day or 10 mg/day of donepezil hydrochloride tablets. The 30-week study was divided into 24-week double-blind active treatment phase followed by 6-week single-blind placebo washout period. The study was designed to compare mg/day or 10 mg/day fixed doses of donepezil hydrochloride tablets to placebo. However, to reduce the likelihood of cholinergic effects, the 10 mg/day treatment was started following an initial 7-day treatment with mg/day doses. Effects on the ADAS-cog Figure illustrates the time course for the change from baseline in ADAS-cog scores for all three dose groups over the 30 weeks of the study. After 24 weeks of treatment, the mean differences in the ADAS-cog change scores for donepezil hydrochloride tablets treated patients compared to the patients on placebo were 2.8 and 3.1 points for the mg/day and 10 mg/day treatments, respectively. These differences were statistically significant. While the treatment effect size may appear to be slightly greater for the 10 mg/day treatment, there was no statistically significant difference between the two active treatments. Following weeks of placebo washout, scores on the ADAS-cog for both the donepezil hydrochloride tablets treatment groups were indistinguishable from those patients who had received only placebo for 30 weeks. This suggests that the beneficial effects of donepezil hydrochloride tablets abate over weeks following discontinuation of treatment and do not represent change in the underlying disease. There was no evidence of rebound effect weeks after abrupt discontinuation of therapy.Figure 1. Time-course of the Change from Baseline in ADAS-cog Score for Patients Completing 24 Weeks of Treatment.Figure 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 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 donepezil hydrochloride tablets have wide range of responses, but that the active treatment groups are more likely to show the greater improvements. 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%, mg/day 85%, and 10 mg/day 68%.Effects on the CIBIC-plusFigure is 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 mg/day and 10 mg/day of donepezil hydrochloride tablets, 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.Fifteen-Week Study In study of 15 weeks duration, patients were randomized to receive single daily doses of placebo or either mg/day or 10 mg/day of donepezil hydrochloride tablets for 12 weeks, followed by 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 mg/day doses. Effects on the ADAS-Cog Figure 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 donepezil hydrochloride tablets treated patients compared to the patients on placebo were 2.7 and 3.0 points each, for the and 10 mg/day donepezil hydrochloride tablets 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 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.Following weeks of placebo washout, scores on the ADAS-cog for both the donepezil hydrochloride tablets treatment groups increased, indicating that discontinuation of donepezil hydrochloride tablets resulted in 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 donepezil hydrochloride tablets abate within weeks of treatment discontinuation. Figure illustrates the cumulative percentages of patients from each of the three treatment groups who attained the measure of improvement in ADAS-cog score shown on the axis. The same three change scores, (7-point and 4-point reductions from baseline or no change in score) as selected for the 30-week study have been used for this illustration. The percentages of patients achieving those results are shown in the inset table. As observed in the 30-week study, the curves demonstrate that patients assigned to either placebo or to donepezil hydrochloride tablets have wide range of responses, but that the donepezil hydrochloride tablets treated patients are more likely to show greater improvements in cognitive performance. Figure 5. Cumulative Percentage of Patients with Specified Changes from Baseline ADAS-cog Scores. The Percentages of Randomized Patients Within Each Treatment Group Who Completed the Study Were: Placebo 93%, mg/day 90%, and 10 mg/day 82%.Effects on the CIBIC-plusFigure is histogram of the frequency distribution of CIBIC-plus scores attained by patients assigned to each of the three treatment groups who completed 12 weeks of treatment. The differences in mean scores for donepezil hydrochloride tablets treated patients compared to the patients on placebo at Week 12 were 0.36 and 0.38 points for the mg/day and 10 mg/day treatment groups, respectively. These differences were statistically significant.Figure 6. Frequency Distribution of CIBIC-plus Scores at Week 12.In both studies, patient age, sex and race were not found to predict the clinical outcome of donepezil hydrochloride tablets treatment. fig.1. Figure 2. Figure 3. 5. figure 5. figure 6. 14.2 Moderate to Severe Alzheimers Disease. The effectiveness of donepezil hydrochloride tablets in the treatment of patients with moderate to severe Alzheimers Disease was established in studies employing doses of 10 mg/day.Swedish Month Study (10 mg/day)The effectiveness of donepezil hydrochloride tablets as treatment for severe Alzheimers disease is demonstrated by the results of randomized, double-blind, placebo-controlled clinical study conducted in Sweden (6 month study) in patients with probable or possible Alzheimers disease diagnosed by NINCDS-ADRDA and DSM-IV criteria, MMSE: range of to 10. Two hundred and forty eight (248) patients with severe Alzheimers disease were randomized to donepezil hydrochloride tablets or placebo. For patients randomized to donepezil hydrochloride tablets, treatment was initiated at mg once daily for 28 days and then increased to 10 mg once daily. At the end of the month treatment period, 90.5% of the donepezil hydrochloride tablets treated patients were receiving the 10 mg/day dose. The mean age of patients was 84.9 years, with range of 59 to 99. Approximately 77 of patients were women, and 23 were men. Almost all patients were Caucasian. Probable Alzheimers disease was diagnosed in the majority of the patients (83.6% of donepezil hydrochloride tablets treated patients and 84.2% of placebo treated patients). Study Outcome Measures The effectiveness of treatment with donepezil hydrochloride tablets was determined using 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 donepezil hydrochloride tablets experienced significant improvement on both measures compared to placebo. The ability of donepezil hydrochloride tablets to improve cognitive performance was assessed with the Severe Impairment Battery (SIB). The SIB, multi-text 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 to 100, with lower scores indicating greater cognitive impairment.Daily function was assessed using the Modified Alzheimers Disease Cooperative Study Activities of Daily Living Inventory for Severe Alzheimers Disease (ADCS-ADL-severe). The ADCS-ADL-severe is derived from the Alzheimers Disease Cooperative Study Activities of Daily Living Inventory, which is comprehensive battery of ADL questions used to measure the functional capabilities of patients. Each ADL text is rated from the highest level of independent performance to complete loss. The ADCS-ADL-severe is subset of 19 texts, including ratings of the patients 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 scoring range of to 54, with the lower scores indicating greater functional impairment. The investigator performs the inventory by interviewing caregiver, in this study nurse staff member, familiar with the functioning of the patient. Effects on the SIB Figure shows the time course for the change from baseline in SIB score for the two treatment groups over the months of the study. At months of treatment, the mean difference in the SIB change scores for donepezil hydrochloride tablets treated patients compared to patients on placebo was 5.9 points. Donepezil hydrochloride tablets treatment was statistically significantly superior to placebo. Figure 7. Time Course of the Change from Baseline in SIB Score for Patients Completing Months of Treatment.Figure 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 donepezil hydrochloride tablets and to placebo have wide range of responses, the curves show that the donepezil hydrochloride tablets group is more likely to show greater improvement in cognitive performance. Figure 8. Cumulative Percentage of Patients Completing Months of Double-blind Treatment with Particular Changes from Baseline in SIB Scores.Effects on the ADCS-ADL-severe Figure illustrates the time course for the change from baseline in ADCS-ADL-severe scores for patients in the two treatment groups over the months of the study. After months of treatment, the mean difference in the ADCS-ADL-severe change scores for donepezil hydrochloride tablets treated patients compared to patients on placebo was 1.8 points. Donepezil hydrochloride tablets treatment was statistically significantly superior to placebo. Figure 10 shows the cumulative percentages of patients from each treatment group with specified changes from baseline ADCS-ADL-severe scores. While both patients assigned to donepezil hydrochloride tablets and placebo have wide range of responses, the curves demonstrate that the donepezil hydrochloride tablets group is more likely to show smaller decline or an improvement. Figure 10. Cumulative Percentage of Patients Completing Months of Double-blind Treatment with Particular Changes from Baseline in ADCS-ADL-Severe Scores.Japanese 24-Week Study (10 mg/day)In study of 24 weeks duration conducted in Japan, 325 patients with severe Alzheimers disease were randomized to doses of mg/day or 10 mg/day of donepezil, administered once daily, or placebo. Patients randomized to treatment with donepezil were to achieve their assigned doses by titration, beginning at mg/day, and extending over maximum of weeks. Two hundred and forty eight (248) patients completed the study, with similar proportions of patients completing the study in each treatment group. The primary efficacy measures for this study were the SIB and CIBIC-plus. At 24 weeks of treatment, statistically significant treatment differences were observed between the 10 mg/day dose of donepezil and placebo on both the SIB and CIBIC-plus. The mg/day dose of donepezil showed statistically significant superiority to placebo on the SIB, but not on the CIBIC-plus.. Figure 7. Figure 8. Figure 9. Figure 10.

CONTRAINDICATIONS SECTION.


4 CONTRAINDICATIONS. oKnown hypersensitivity to donepezil hydrochloride or to piperidine derivatives (4). oKnown hypersensitivity to donepezil hydrochloride or to piperidine derivatives (4). Donepezil hydrochloride tablets are contraindicated in patients with known hypersensitivity to donepezil hydrochloride or to piperidine derivatives.

DESCRIPTION SECTION.


11 DESCRIPTION. Donepezil hydrochloride is reversible inhibitor of the enzyme acetylcholinesterase, known chemically as (+-)-2, 3-dihydro-5, 6-dimethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-inden-1-one hydrochloride. Donepezil hydrochloride is commonly referred to in the pharmacological literature as E2020. It has an empirical formula of C24H29NO3HCl and molecular weight of 415.96. Donepezil hydrochloride, USP is 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.Donepezil hydrochloride is available for oral administration in film-coated tablets containing or 10 mg of donepezil hydrochloride, USP.Inactive ingredients in mg and 10 mg tablets are lactose monohydrate, magnesium stearate, maize starch (Zea mays) and microcrystalline cellulose. The film coating contains hypromellose, polyethylene glycol, talc and titanium dioxide. Additionally, the 10 mg tablet contains ferric oxide red and ferric oxide yellow as coloring agents. str.

DOSAGE & ADMINISTRATION SECTION.


2 DOSAGE AND ADMINISTRATION. oMild to Moderate Alzheimers Disease: mg to 10 mg once daily (2.1)oModerate to Severe Alzheimers Disease: 10 mg once daily (2.2). oMild to Moderate Alzheimers Disease: mg to 10 mg once daily (2.1). oModerate to Severe Alzheimers Disease: 10 mg once daily (2.2). 2.1 Dosing in Mild to Moderate Alzheimers Disease. The recommended starting dosage of donepezil hydrochloride tablets is mg administered once per day in the evening, just prior to retiring. The maximum recommended dosage of donepezil hydrochloride tablets in patients with mild to moderate Alzheimers disease is 10 mg per day. dose of 10 mg should not be administered until patients have been on daily dose of mg for to weeks.. 2.2 Dosing in Moderate to Severe Alzheimers Disease. The recommended starting dosage of donepezil hydrochloride tablets is mg administered once per day in the evening, just prior to retiring. dose of 10 mg should not be administered until patients have been on daily dose of mg for to weeks.. 2.3 Administration Information. Donepezil hydrochloride tablets should be taken in the evening, just prior to retiring. Donepezil hydrochloride tablets can be taken with or without food.

DOSAGE FORMS & STRENGTHS SECTION.


3 DOSAGE FORMS AND STRENGTHS. oTablets: mg and 10 mg (3). oTablets: mg and 10 mg (3). Donepezil hydrochloride tablets are supplied as film-coated, round tablets containing mg or 10 mg of donepezil hydrochloride.oThe mg tablets are white to off white, circular, biconvex, film coated tablets debossed with on one side and plain on other side.oThe 10 mg tablets are peach colored, circular, biconvex, film coated tablets debossed with 10 on one side and plain on other side.. oThe mg tablets are white to off white, circular, biconvex, film coated tablets debossed with on one side and plain on other side.. oThe 10 mg tablets are peach colored, circular, biconvex, film coated tablets debossed with 10 on one side and plain on other side.

DRUG INTERACTIONS SECTION.


7 DRUG INTERACTIONS. oCholinesterase inhibitors have the potential to interfere with the activity of anticholinergic medications (7.1).oA synergistic effect may be expected with concomitant administration of succinylcholine, similar neuromuscular blocking agents, or cholinergic agonists (7.2).. oCholinesterase inhibitors have the potential to interfere with the activity of anticholinergic medications (7.1).. oA synergistic effect may be expected with concomitant administration of succinylcholine, similar neuromuscular blocking agents, or cholinergic agonists (7.2).. 7.1 Use with Anticholinergics. Because of their mechanism of action, cholinesterase inhibitors have the potential to interfere with the activity of anticholinergic medications. 7.2 Use with Cholinomimetics and Other Cholinesterase Inhibitors. synergistic effect may be expected when cholinesterase inhibitors are given concurrently with succinylcholine, similar neuromuscular blocking agents, or cholinergic agonists such as bethanechol.

GERIATRIC USE SECTION.


8.5 Geriatric Use. Alzheimers disease is disorder occurring primarily in individuals over 55 years of age. The mean age of patients enrolled in the clinical studies with donepezil hydrochloride tablets 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 events reported by patient groups >= 65 years old and 65 years old.

HOW SUPPLIED SECTION.


16 HOW SUPPLIED/STORAGE AND HANDLING. 16.1 Donepezil Hydrochloride Tablets. Donepezil hydrochloride tablets, USP mg are white to off white, circular, biconvex, film coated tablets debossed with on one side and plain on other side.Carton of 100 tablets (10 tablets each blister pack 10) NDC 0904-6477-61 Donepezil hydrochloride tablets, USP 10 mg are peach colored, circular, biconvex, film coated tablets debossed with 10 on one side and plain on other side.Carton of 100 tablets (10 tablets each blister pack 10) NDC 0904-6478-61Storage: Store at 20 to 25C (68 to 77F); excursions permitted to 15 to 30C (59 to 86F). [see USP Controlled Room Temperature].

MECHANISM OF ACTION SECTION.


12.1 Mechanism of Action. Current theories on the pathogenesis of the cognitive signs and symptoms of Alzheimers disease attribute some of them to 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.

NONCLINICAL TOXICOLOGY SECTION.


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 86 times the maximum recommended human dose [MRHD] of 10 mg/day on mg/m2 basis), or in 104-week carcinogenicity study in rats at oral doses up to 30 mg/kg/day (approximately 29 times the MRHD on mg/m2 basis).Donepezil was negative in 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 10 times the MRHD on mg/m2 basis) when administered to males and females prior to and during mating and continuing in females through implantation.. 13.2 Animal Toxicology andor 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.

OVERDOSAGE SECTION.


10 OVERDOSAGE. Because strategies for the management of overdose are continually evolving, it is advisable to contact 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 possibility and may result in death if respiratory muscles are involved. Tertiary anticholinergics such as atropine may be used as an antidote for donepezil hydrochloride tablets 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 donepezil hydrochloride 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.

PACKAGE LABEL.PRINCIPAL DISPLAY PANEL.


Package/Label Display Panel Donepezil Hydrochloride Tablets, USP5 mg100 Tablets. carton label.

PEDIATRIC USE SECTION.


8.4 Pediatric Use. The safety and effectiveness in pediatric patients have not been established.

PHARMACOKINETICS SECTION.


12.3 Pharmacokinetics. Pharmacokinetics of donepezil are linear over dose range of to 10 mg given once daily. The rate and extent of absorption of donepezil hydrochloride tablets are not influenced by food. Donepezil hydrochloride ODT mg and 10 mg are bioequivalent to donepezil hydrochloride mg and 10 mg tablets, respectively. The elimination half life of donepezil is about 70 hours, and the mean apparent plasma clearance (Cl/F) is 0.13 to 0.19 L/hr/kg. Following multiple dose administration, donepezil accumulates in plasma by to fold, and steady state is reached within 15 days. The steady state volume of distribution is 12 to 16 L/kg. Donepezil is approximately 96% bound to human plasma proteins, mainly to albumins (about 75%) and alpha1 acid glycoprotein (about 21%) over the concentration range of to 1000 ng/mL. Donepezil is both excreted in the urine intact and extensively metabolized to four major metabolites, two of which are known to be active, and number of minor metabolites, not all of which have been identified. Donepezil is metabolized by CYP 450 isoenzymes 2D6 and 3A4 and undergoes glucuronidation. Following administration of 14C-labeled donepezil, plasma radioactivity, expressed as percent of the administered dose, was present primarily as intact donepezil (53%) and as 6-O-desmethyl donepezil (11%), which has been reported to inhibit AChE to the same extent as donepezil in vitro and was found in plasma at concentrations equal to about 20% of donepezil. Approximately 57% and 15% of the total radioactivity was recovered in urine and feces, respectively, over period of 10 days, while 28% remained unrecovered, with about 17% of the donepezil dose recovered in the urine as unchanged drug. Examination of the effect of CYP2D6 genotype in Alzheimers patients showed differences in clearance values among CYP2D6 genotype subgroups. When compared to the extensive metabolizers, poor metabolizers had 31.5% slower clearance and ultra-rapid metabolizers had 24% faster clearance. Hepatic Disease In study of 10 patients with stable alcoholic cirrhosis, the clearance of donepezil hydrochloride was decreased by 20% relative to 10 healthy age- and sex-matched subjects. Renal DiseaseIn study of 11 patients with moderate to severe renal impairment (ClC 18 mL/min/1.73 m2) the clearance of donepezil hydrochloride did not differ from 11 age- and sex-matched healthy subjects. Age No formal pharmacokinetic study was conducted to examine age-related differences in the pharmacokinetics of donepezil hydrochloride. Population pharmacokinetic analysis suggested that the clearance of donepezil in patients decreases with increasing age. When compared with 65-year old subjects, 90-year old subjects have 17% decrease in clearance, while 40-year old subjects have 33% increase in clearance. The effect of age on donepezil clearance may not be clinically significant. Gender and Race No specific pharmacokinetic study was conducted to investigate the effects of gender and race on the disposition of donepezil hydrochloride. However, retrospective pharmacokinetic analysis and population pharmacokinetic analysis of plasma donepezil concentrations measured in patients with Alzheimers disease indicates that gender and race (Japanese and Caucasians) did not affect the clearance of donepezil hydrochloride to an important degree. Body weight There was 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 value of 10 L/hr for 70 kg individuals.Drug Interactions Effect of Donepezil Hydrochloride Tablets on the Metabolism of Other Drugs No in vivo clinical trials have investigated the effect of donepezil hydrochloride tablets 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 low rate of binding to these enzymes (mean Ki about 50 to 130 uM), 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 donepezil hydrochloride tablets have any potential for enzyme induction is not known. Formal pharmacokinetic studies evaluated the potential of donepezil hydrochloride tablets for interaction with theophylline, cimetidine, warfarin, digoxin and ketoconazole. No effects of donepezil hydrochloride tablets on the pharmacokinetics of these drugs were observed.Effect of Other Drugs on the Metabolism of Donepezil Hydrochloride TabletsKetoconazole and quinidine, strong inhibitors of CYP450 3A and 2D6, respectively, inhibit donepezil metabolism in vitro. Whether there is 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 Alzheimers disease patients taking donepezil hydrochloride tablets 10 mg. This represented an average effect of weak, moderate, and strong CYP2D6 inhibitors. In 7-day crossover study in 18 healthy volunteers, ketoconazole (200 mg q.d.) increased mean donepezil (5 mg q.d.) concentrations (AUC0 to 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 donepezil hydrochloride tablets.Formal pharmacokinetic studies demonstrated that the metabolism of donepezil hydrochloride tablets is not significantly affected by concurrent administration of digoxin or cimetidine.An in vitro study showed that donepezil was not substrate of P-glycoprotein.Drugs Highly Bound to Plasma ProteinsDrug displacement studies have been performed in vitro between this highly bound drug (96%) and other drugs such as furosemide, digoxin, and warfarin. Donepezil hydrochloride at concentrations of 0.3 to 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 donepezil hydrochloride to human albumin was not affected by furosemide, digoxin and warfarin.

PREGNANCY SECTION.


8.1 Pregnancy. Risk SummaryThere are no adequate data on the developmental risks associated with the use of donepezil in pregnant women. In animal studies, developmental toxicity was not observed when donepezil was administered to pregnant rats and rabbits during organogenesis, but administration to rats during the latter part of pregnancy and throughout lactation resulted in increased stillbirths and decreased offspring survival at clinically relevant doses [see Data]. In the U.S. general population, the estimated background risks of major birth defects and miscarriage in clinically recognized pregnancies are 2% to 4% and 15% to 20%, respectively. The background risks of major birth defects and miscarriage for the indicated population are unknown.DataAnimal DataOral 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 16 times the maximum recommended human dose [MRHD] of 10 mg/day on mg/m2 basis) and 10 mg/kg/day (approximately 20 times the MRHD on mg/m2 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 at the highest dose. The no-effect dose of mg/kg/day is approximately times the MRHD on mg/m2 basis.

SPL UNCLASSIFIED SECTION.


Donepezil hydrochloride tablets, USP are indicated for the treatment of dementia of the Alzheimers type. Efficacy has been demonstrated in patients with mild, moderate, and severe Alzheimers disease.

USE IN SPECIFIC POPULATIONS SECTION.


8 USE IN SPECIFIC POPULATIONS. Pregnancy: Based on animal data, may cause fetal harm (8.1). 8.1 Pregnancy. Risk SummaryThere are no adequate data on the developmental risks associated with the use of donepezil in pregnant women. In animal studies, developmental toxicity was not observed when donepezil was administered to pregnant rats and rabbits during organogenesis, but administration to rats during the latter part of pregnancy and throughout lactation resulted in increased stillbirths and decreased offspring survival at clinically relevant doses [see Data]. In the U.S. general population, the estimated background risks of major birth defects and miscarriage in clinically recognized pregnancies are 2% to 4% and 15% to 20%, respectively. The background risks of major birth defects and miscarriage for the indicated population are unknown.DataAnimal DataOral 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 16 times the maximum recommended human dose [MRHD] of 10 mg/day on mg/m2 basis) and 10 mg/kg/day (approximately 20 times the MRHD on mg/m2 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 at the highest dose. The no-effect dose of mg/kg/day is approximately times the MRHD on mg/m2 basis. 8.2 Lactation. Risk SummaryThere 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 mothers clinical need for donepezil and any potential adverse effects on the breastfed infant from donepezil 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. Alzheimers disease is disorder occurring primarily in individuals over 55 years of age. The mean age of patients enrolled in the clinical studies with donepezil hydrochloride tablets 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 events reported by patient groups >= 65 years old and 65 years old.

WARNINGS AND PRECAUTIONS SECTION.


5 WARNINGS AND PRECAUTIONS. oCholinesterase inhibitors are likely to exaggerate succinylcholine-type muscle relaxation during anesthesia (5.1)oCholinesterase inhibitors may have vagotonic effects on the sinoatrial and atrioventricular nodes manifesting as bradycardia or heart block (5.2)oDonepezil hydrochloride tablets can cause vomiting. Patients should be observed closely at initiation of treatment and after dose increases (5.3)oPatients should be monitored closely for symptoms of active or occult gastrointestinal (GI) bleeding, especially those at increased risk for developing ulcers (5.4)oCholinomimetics may cause bladder outflow obstructions (5.6)oCholinomimetics are believed to have some potential to cause generalized convulsions (5.7)oCholinesterase inhibitors should be prescribed with care to patients with history of asthma or obstructive pulmonary disease (5.8). oCholinesterase inhibitors are likely to exaggerate succinylcholine-type muscle relaxation during anesthesia (5.1). oCholinesterase inhibitors may have vagotonic effects on the sinoatrial and atrioventricular nodes manifesting as bradycardia or heart block (5.2). oDonepezil hydrochloride tablets can cause vomiting. Patients should be observed closely at initiation of treatment and after dose increases (5.3). oPatients should be monitored closely for symptoms of active or occult gastrointestinal (GI) bleeding, especially those at increased risk for developing ulcers (5.4). oCholinomimetics may cause bladder outflow obstructions (5.6). oCholinomimetics are believed to have some potential to cause generalized convulsions (5.7). oCholinesterase inhibitors should be prescribed with care to patients with history of asthma or obstructive pulmonary disease (5.8). 5.1 Anesthesia. Donepezil hydrochloride, as cholinesterase inhibitor, is likely to exaggerate succinylcholine-type muscle relaxation during anesthesia.. 5.2 Cardiovascular Conditions. Because of their pharmacological action, cholinesterase inhibitors may have vagotonic effects on the sinoatrial and atrioventricular nodes. This effect may manifest as bradycardia or heart block in patients both with and without known underlying cardiac conduction abnormalities. Syncopal episodes have been reported in association with the use of donepezil hydrochloride tablets. 5.3 Nausea and Vomiting. Donepezil hydrochloride tablets, as predictable consequence of their pharmacological properties, have been shown to produce diarrhea, nausea, and vomiting. These effects, when they occur, appear more frequently with the 10 mg/day dose than with the mg/day dose. Although in most cases, these effects have been transient, sometimes lasting one to three weeks, and have resolved during continued use of donepezil hydrochloride tablets, patients should be observed closely at the initiation of treatment and after dose increases. 5.4 Peptic Ulcer Disease and GI Bleeding. Through their primary action, cholinesterase inhibitors may be expected to increase gastric acid secretion due to increased cholinergic activity. Therefore, patients should be monitored closely for symptoms of active or occult gastrointestinal bleeding, especially those at increased risk for developing ulcers, e.g., those with history of ulcer disease or those receiving concurrent nonsteroidal anti-inflammatory drugs (NSAIDs). Clinical studies of donepezil hydrochloride tablets in dose of mg/day to 10 mg/day have shown no increase, relative to placebo, in the incidence of either peptic ulcer disease or gastrointestinal bleeding. 5.6 Genitourinary Conditions. Although not observed in clinical trials of donepezil hydrochloride tablets, cholinomimetics may cause bladder outflow obstruction. 5.7 Neurological Conditions: Seizures. Cholinomimetics are believed to have some potential to cause generalized convulsions. However, seizure activity also may be manifestation of Alzheimers disease. 5.8 Pulmonary Conditions. Because of their cholinomimetic actions, cholinesterase inhibitors should be prescribed with care to patients with history of asthma or obstructive pulmonary disease.