Rivastigmine Drug Information
Generic name: RIVASTIGMINE TARTRATE
Uses of Rivastigmine
Alzheimer’s Disease Rivastigmine tartrate capsules are indicated for the treatment of mild-to-moderate
dementia of the Alzheimer's type (AD).
Parkinson’s Disease Dementia Rivastigmine tartrate capsules are indicated for the treatment of
mild-to-moderate dementia associated with Parkinson’s disease (PD).
Dosage & Administration of Rivastigmine
Dosing in Alzheimer's Disease Rivastigmine tartrate capsules should be taken with meals
in divided doses in the morning and evening. The recommended dosage of rivastigmine tartrate capsules in Alzheimer’s disease (AD) is 6 mg to 12 mg per day, administered twice a day (daily doses of 3 mg to 6 mg twice a day). There is evidence from the clinical trials that doses at the higher end of this range may be more beneficial. Initial Dose Initiate treatment with the 1.5 mg twice a day with rivastigmine tartrate capsules.
Dose Titration After a minimum of 2 weeks and if well tolerated, increase the dose to 3 mg twice a day. Subsequent increases to 4.5 mg twice a day and 6 mg twice a day should be attempted after a minimum of 2 weeks at the previous dose and if well tolerated. The maximum dose is 6 mg twice a day (12 mg per day).
Dosing in Parkinson's Disease Dementia Rivastigmine tartrate capsules should be taken with
meals in divided doses in the morning and evening. The dosage of rivastigmine tartrate capsules shown to be effective in the single controlled clinical trial conducted in dementia associated with Parkinson’s disease is 3 mg to 12 mg per day, administered twice a day (daily doses of 1.5 mg to 6 mg twice a day). Initial Dose Initiate treatment with the 1.5 mg twice a day with rivastigmine tartrate capsules. Dose Titration After a minimum of 4 weeks and if well tolerated, increase the dose to 3 mg twice a day.
Subsequent increases to 4.5 mg twice a day and 6 mg twice a day should be attempted after a minimum of 4 weeks at the previous dose and if well tolerated. The maximum dose is 6 mg twice a day (12 mg per day).
Interruption of Treatment
If adverse effects (e.g., nausea, vomiting, abdominal pain, loss of appetite) cause intolerance during treatment, the patient should be instructed to discontinue treatment for several doses and then restart at the same or next lower dose level. If dosing is interrupted for 3 days or fewer, restart treatment with the same or lower dose of rivastigmine tartrate capsules. If dosing is interrupted for more than 3 days, treatment should be restarted with 1.5 mg twice a day and titrated as described above.
Dosing in Specific Populations Dosing Modifications in Patients with Renal Impairment Patients
with moderate and severe renal impairment may be able to only tolerate lower doses. Dosing Modifications in Patients with Hepatic Impairment Patients with mild (Child-Pugh score 5 to 6) and moderate (Child-Pugh score 7 to 9) hepatic impairment may be able to only tolerate lower doses. No data are available on the use of rivastigmine in patients with severe hepatic impairment.
Dosing Modifications in Patients with Low Body Weight Carefully titrate and monitor patients with low body weight (less than 50 kg) for toxicities (e.g., excessive nausea, vomiting), and consider reducing the dose if such toxicities develop.
Important
Administration Instructions Rivastigmine tartrate oral solution and rivastigmine tartrate capsules may be interchanged at equal doses.
Side Effects of Rivastigmine
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. Rivastigmine tartrate has been administered to over 5,297 individuals during clinical trials worldwide. Of these, 4,326 patients have been treated for at least 3 months, 3,407 patients have been treated for at least 6 months, 2,150 patients have been treated for 1 year, 1,250 patients have been treated for 2 years, and 168 patients have been treated for over 3 years.
With regard to exposure to the highest dose, 2,809 patients were exposed to doses of 10 mg to 12 mg, 2,615 patients treated for 3 months, 2,328 patients treated for 6 months, 1,378 patients treated for 1 year, 917 patients treated for 2 years, and 129 patients treated for over 3 years. Mild-to-Moderate Alzheimer’s Disease Most Common Adverse Reactions The most common adverse reactions, defined as those occurring at a frequency of at least 5% and twice the placebo rate, are largely predicted by rivastigmine tartrate’s cholinergic effects. These include nausea, vomiting, anorexia, dyspepsia, and asthenia.
Gastrointestinal Adverse Reactions Rivastigmine tartrate use is associated with significant nausea, vomiting, and weight loss . Discontinuation Rates The rate of discontinuation due to adverse events in controlled clinical trials of rivastigmine tartrate was 15% for patients receiving 6 mg to 12 mg per day compared to 5% for patients on placebo during forced weekly dose titration. While on a maintenance dose, the rates were 6% for patients on rivastigmine tartrate compared to 4% for those on placebo. The most common adverse reactions leading to discontinuation, defined as those occurring in at least 2% of patients and at twice the incidence seen in placebo patients, are shown in Table 1. Table 1: Most Frequent Adverse Reactions Leading to Withdrawal from Clinical Trials During Titration and Maintenance in Patients Receiving 6 mg to 12 mg per day Rivastigmine Tartrate Using a Forced-Dose Titration Study Phase Titration Maintenance Overall Rivastigmine Tartrate Placebo Rivastigmine Tartrate Placebo Rivastigmine Tartrate Placebo ≥6 to 12 mg/day ≥6 to 12 mg/day ≥6 to 12 mg/day (n=1,189) (n=868) (n=987) (n=788) (n=1,189) (n=868) Event/% Discontinuing Nausea 8 <1 1 <1 8 1 Vomiting 4 <1 1 <1 5 <1 Anorexia 2 0 1 <1 3 <1 Dizziness 2 <1 1 <1 2 <1 Adverse Reactions Observed at an Incidence of at Least 2% Table 2 lists adverse reactions that occurred in at least 2% of patients in placebo-controlled trials, and for which the rate of occurrence was greater for patients treated with rivastigmine tartrate doses of 6 mg to 12 mg per day than for those treated with placebo.
In general, adverse reactions were less frequent later in the course of treatment. No systematic effect of race or age could be determined from the incidence of adverse reactions in the controlled studies. Nausea, vomiting and weight loss were more frequent in women than men.
Table 2: Proportion of Adverse Reactions Observed with a Frequency of Greater Than or Equal to 2% and at a Rate Greater than Placebo in Clinical Trials Body System/Adverse Reaction Rivastigmine Tartrate (6 to 12 m g/day) (n=1,189) Placebo (n=868) Percent of Patients with any Adverse Event 92 79 Autonomic Nervous System Increased Sweating 4 1 Syncope 3 2 Body as a Whole Fatigue 9 5 Asthenia 6 2 Malaise 5 2 Decreased Weight ** 3 <1 Cardiovascular Disorders, General Hypertension 3 2 Central and Peripheral Nervous System Dizziness 21 11 Headache 17 12 Somnolence 5 3 Tremor 4 1 Gastrointestinal System Nausea* 47 12 Vomiting* 31 6 Diarrhea 19 11 Anorexia*** 17 3 Abdominal Pain 13 6 Dyspepsia 9 4 Psychiatric Disorders Insomnia 9 7 Confusion 8 7 Depression 6 4 Anxiety 5 3 Hallucination 4 3 Aggressive Reaction 3 2 Resistance Mechanism Disorders Urinary Tract Infection 7 6 * Nausea and Vomiting: In the controlled clinical trials, 47% of the patients treated with a rivastigmine tartrate dose in the therapeutic range of 6 mg to 12 mg per day (n=1189) developed nausea (compared with 12% in placebo). A total of 31% of rivastigmine tartrate -treated patients developed at least 1 episode of vomiting (compared with 6% for placebo). The rate of vomiting was higher during the titration phase (24% versus 3% for placebo) than in the maintenance phase (14% versus 3% for placebo). The rates were higher in women than men. Five percent of patients discontinued for vomiting, compared to less than 1% for patients on placebo. Vomiting was severe in 2% of rivastigmine tartrate-treated patients and was rated as mild or moderate each in 14% of patients.
The rate of nausea was higher during the titration phase (43% versus 9% for placebo) than in the maintenance phase (17% versus 4% for placebo). ** Weight Decreased: In the controlled trials, approximately 26% of women on high doses of rivastigmine tartrate (greater than 9 mg per day) had weight loss equal to or greater than 7% of their baseline weight compared to 6% in the placebo-treated patients. About 18% of the males in the high-dose group experienced a similar degree of weight loss compared to 4% in placebo-treated patients. It is not clear how much of the weight loss was associated with anorexia, nausea, vomiting, and the diarrhea associated with the drug. *** Anorexia: In the controlled clinical trials, of the patients treated with a rivastigmine tartrate dose of 6 mg to 12 mg per day, 17% developed anorexia compared to 3% of the placebo patients.
Neither the time course nor the severity of the anorexia is known. Mild-to-Moderate Parkinson’s Disease Dementia Rivastigmine tartrate has been administered to 779 individuals during clinical trials worldwide. Of these, 663 patients have been treated for at least 3 months, 476 patients have been treated for at least 6 months, and 313 patients have been treated for 1 year.
Most Common Adverse Reactions The most common adverse reactions, defined as those occurring at a frequency of at least 5% and twice the placebo rate, are largely predicted by rivastigmine tartrate’s cholinergic effects. These include nausea, vomiting, tremor, anorexia, and dizziness. Discontinuation Rates The rate of discontinuation due to adverse events in the single placebo-controlled trial of rivastigmine tartrate was 18% for patients receiving 3 mg to 12 mg per day compared to 11% for patients on placebo during the 24-week study.
The most frequent adverse reactions that led to discontinuation from this study, defined as those occurring in at least 1% of patients receiving rivastigmine tartrate and more frequent than those receiving placebo, were nausea (3.6% rivastigmine tartrate versus 0.6% placebo), vomiting (1.9% rivastigmine tartrate versus 0.6% placebo), and tremor (1.7% rivastigmine tartrate versus 0% placebo). Adverse Reactions Observed at an Incidence of at Least 2% Table 3 lists adverse reactions that occurred in at least 2% of patients in a single placebo-controlled trial and during the first 24 weeks of a 76-week open-label active-controlled trial for which the rate of occurrence was greater for patients treated with rivastigmine tartrate doses of 3 mg to 12 mg per day than for those treated with placebo in the placebo-controlled trial. In general, adverse reactions were less frequent later in the course of treatment. Table 3: Proportion of Adverse Reactions Observed at a Frequency Greater Than or Equal to 2% and Occurring at Rate Greater than Placebo in Clinical Trials Active- Controlled Study Placebo-Controlled Study Body System/Adverse Reaction Rivastigmine Tartrate (3 to 12 mg/day) (n=294) Rivastigmine Tartrate (3 to 12 mg/day) (n=362) Placebo (n=179) Percent of Patients with any Adverse Reaction 88 84 71 Gastrointestinal Disorders Nausea 38 29 11 Vomiting 13 17 2 Diarrhea 8 7 4 Upper Abdominal Pain 4 4 1 Salivary hypersecretion 2 1 0 General Disorders and Administrative Site Conditions Fall 10 6 6 Fatigue 5 4 3 Asthenia 4 2 1 Metabolism and Nutritional Disorders Anorexia - 6 3 Decreased Appetite 5 8 5 Dehydration 1 2 1 Nervous System Disorders Tremor 23 10 4 Dizziness 8 6 1 Headache 4 4 3 Somnolence 6 4 3 Parkinson’s Disease (worsening) -* 3 1 Bradykinesia 3 3 2 Dyskinesia 3 1 1 Cogwheel rigidity 3 1 0 Hypokinesia 2 1 0 Parkinsonism - 2 1 Psychiatric Disorders Anxiety 4 4 1 Insomnia 2 3 2 Restlessness 1 3 2 Skin and Subcutaneous Tissue Disorders Increased Sweating 2 2 1 *Parkinson’s disease (worsening) in the active-controlled study was assessed by reported pre-identified adverse events (tremor, cogwheel rigidity, fall), each of them listed with corresponding frequencies.
Postmarketing Experience
The following adverse reactions have been identified during post approval use of rivastigmine tartrate capsules. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Cardiac Disorders: Tachycardia Hepatobiliary Disorders: Abnormal liver function tests, hepatitis Nervous System Disorder: seizure Psychiatric Disorders: Aggression, nightmares Skin and Subcutaneous Tissue Disorders: Allergic dermatitis, application site hypersensitivity (patch), blister, disseminated allergic dermatitis, Stevens-Johnson syndrome, urticaria
Warnings & Cautions for Rivastigmine
Gastrointestinal Adverse Reactions Rivastigmine tartrate can cause gastrointestinal adverse reactions, including significant
nausea, vomiting, diarrhea, anorexia/decreased appetite, and weight loss. Dehydration may result from prolonged vomiting or diarrhea and can be associated with serious outcomes. The incidence and severity of these reactions are dose-related . For this reason, patients should always be started at a dose of 1.5 mg twice a day and titrated to their maintenance dose.
If treatment is interrupted for longer than 3 days, treatment should be reinitiated with the lowest daily dose to reduce the possibility of severe vomiting and its potentially serious sequelae (e.g., there has been one postmarketing report of severe vomiting with esophageal rupture following inappropriate reinitiation of treatment with a 4.5-mg dose after 8 weeks of treatment interruption). Inform caregivers to monitor for gastrointestinal adverse reactions and to inform the physician if they occur. It is critical to inform caregivers that if therapy has been interrupted for more than 3 days because of intolerance, the next dose should not be administered without contacting the physician regarding proper retitration.
Allergic Dermatitis
There have been isolated postmarketing reports of patients experiencing disseminated allergic dermatitis when administered rivastigmine irrespective of the route of administration (oral or transdermal). Treatment should be discontinued if disseminated allergic dermatitis occurs . Patients and caregivers should be instructed accordingly . In patients who develop application site reactions, suggestive of allergic contact dermatitis to rivastigmine tartrate patch and who still require rivastigmine, treatment should be switched to oral rivastigmine only after negative allergy testing and under close medical supervision. It is possible that some patients sensitized to rivastigmine by exposure to rivastigmine patch may not be able to take rivastigmine in any form.
Other Adverse Reactions from Increased Cholinergic Activity Neurologic Effects Extrapyramidal Symptoms: Cholinomimetics
including rivastigmine may exacerbate or induce extrapyramidal symptoms. Worsening of parkinsonian symptoms, particularly tremor has been observed in patients with dementia associated with Parkinson’s disease who were treated with rivastigmine tartrate capsules. Seizures: Drugs that increase cholinergic activity are believed to have some potential for causing seizures.
However, seizure activity also may be a manifestation of Alzheimer’s disease. Peptic Ulcers/Gastrointestinal Bleeding Cholinesterase inhibitors, including rivastigmine, may be expected to increase gastric acid secretion due to increased cholinergic activity. Monitor patients using rivastigmine tartrate capsules for symptoms of active or occult gastrointestinal bleeding, especially those at increased risk for developing ulcers, e.g., those with a history of ulcer disease or those receiving concurrent nonsteroidal anti-inflammatory drugs (NSAIDs). Clinical studies of rivastigmine have shown no significant increase, relative to placebo, in the incidence of either peptic ulcer disease or gastrointestinal bleeding.
Use with Anesthesia Rivastigmine, as a cholinesterase inhibitor, is likely to exaggerate succinylcholine-type muscle relaxation during anesthesia. Cardiac Conduction Effects Because rivastigmine increases cholinergic activity, use of rivastigmine may have vagotonic effects on heart rate (e.g., bradycardia). The potential for this action may be particularly important in patients with sick sinus syndrome or other supraventricular cardiac conduction conditions. In clinical trials, rivastigmine was not associated with any increased incidence of cardiovascular adverse events, heart rate or blood pressure changes, or electrocardiogram (ECG) abnormalities.
Syncopal episodes have been reported in 3% of patients receiving 6 mg to 12 mg per day of rivastigmine tartrate, compared to 2% of placebo patients. Genitourinary Effects Although not observed in clinical trials of rivastigmine, drugs that increase cholinergic activity may cause urinary obstruction. Pulmonary Effects Drugs that increase cholinergic activity, including rivastigmine, should be used with care in patients with a history of asthma or obstructive pulmonary disease.
Impairment in Driving or Use of Machinery Dementia may cause gradual impairment
of driving performance or compromise the ability to use machinery. The administration of rivastigmine may also result in adverse reactions that are detrimental to these functions. During treatment with rivastigmine tartrate capsules, routinely evaluate the patient’s ability to continue driving or operating machinery.
Drug Interactions with Rivastigmine
Metoclopramide Due to the risk of additive extrapyramidal adverse reactions, the concomitant
use of metoclopramide and rivastigmine tartrate is not recommended.
Cholinomimetic and Anticholinergic Medications Rivastigmine tartrate may increase the cholinergic effects of
other cholinomimetic medications and may also interfere with the activity of anticholinergic medications (e.g., oxybutynin, tolterodine). Concomitant use of rivastigmine tartrate with medications having these pharmacologic effects is not recommended unless deemed clinically necessary.
Beta-blockers Additive bradycardic effects resulting in syncope may occur when rivastigmine tartrate
is used concomitantly with beta-blockers, especially cardioselective beta-blockers (including atenolol). Concomitant use of rivastigmine tartrate with beta-blockers is not recommended.
Pregnancy Safety for Rivastigmine
Pregnancy Risk Summary There are no adequate data on the developmental risks associated with the use of rivastigmine tartrate in pregnant women. In animals, no adverse effects on embryo-fetal development were observed at oral doses 2 to 4 times the maximum recommended human dose (MRHD) (see Data). The background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
Data Animal Data Oral administration of rivastigmine to pregnant rats and rabbits throughout organogenesis produced no adverse effects on embryo-fetal development up to the highest dose tested (2.3 mg/kg/day), which is 2 and 4 times, respectively, the MRHD of 12 mg per day on a body surface area (mg/m 2 ) basis.
Pediatric Use of Rivastigmine
Pediatric Use Safety and effectiveness in pediatric patients have not been established. The use of rivastigmine tartrate in pediatric patients (below 18 years of age) is not recommended.
Contraindications for Rivastigmine
Rivastigmine tartrate capsules are contraindicated in patients with: known hypersensitivity to rivastigmine, other carbamate derivatives or other components of the formulation a previous history of application site reaction with rivastigmine transdermal patch suggestive of allergic contact dermatitis, in the absence of negative allergy testing Isolated cases of generalized skin reactions have been described in postmarketing experience. Known hypersensitivity to rivastigmine, other carbamate derivatives or other components of the formulation. History of application site reaction with rivastigmine transdermal patch suggestive of allergic contact dermatitis, in the absence of negative allergy testing
Overdosage Information for Rivastigmine
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 rivastigmine has a short plasma half-life of about 1 hour and a moderate duration of acetylcholinesterase inhibition of 8 to 10 hours, it is recommended that in cases of asymptomatic overdoses, no further dose of rivastigmine tartrate capsules should be administered for the next 24 hours. 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. Atypical responses in blood pressure and heart rate have been reported with other drugs that increase cholinergic activity when coadministered with quaternary anticholinergics such as glycopyrrolate.
Additional symptoms associated with rivastigmine overdose are diarrhea, abdominal pain, dizziness, tremor, headache, somnolence, confusional state, hyperhidrosis, hypertension, hallucinations and malaise. Due to the short half-life of rivastigmine, dialysis (hemodialysis, peritoneal dialysis, or hemofiltration) would not be clinically indicated in the event of an overdose. In overdoses accompanied by severe nausea and vomiting, the use of antiemetics should be considered.
A fatal outcome has been rarely reported with rivastigmine.
Clinical Studies of Rivastigmine
Mild-to-Moderate Alzheimer’s Disease The effectiveness of rivastigmine tartrate as a treatment for Alzheimer's disease is demonstrated by the results of 2 randomized, double-blind, placebo-controlled clinical investigations ( Study 1 and Study 2 ) in patients with Alzheimer's disease. The mean age of patients participating in rivastigmine tartrate trials was 73 years with a range of 41 to 95. Approximately 59% of patients were women and 41% were men. The racial distribution was Caucasian 87%, Black 4%, and other races 9%. In each study, the effectiveness of rivastigmine tartrate was evaluated using a dual outcome assessment strategy.
The ability of rivastigmine tartrate 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 ADAS-cog of approximately 23 units, with a range from 1 to 61. Experience gained in longitudinal studies of ambulatory patients with mild-to-moderate Alzheimer's disease suggests that they gain 6 to 12 units a year on the ADAS-cog. Lesser degrees of change, however, are seen in patients with very mild or very advanced disease because 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 rivastigmine tartrate trials was approximately 3 to 8 units per year. The ability of rivastigmine tartrate to produce an overall clinical effect was assessed using a Clinician's Interview-Based Impression of Change (CIBIC) that required the use of caregiver information, the CIBIC-Plus. The CIBIC-Plus is not a single instrument and is not a standardized instrument like the ADAS-cog.
Clinical trials for investigational drugs have used a variety of CIBIC formats, each different in terms of depth and structure. As such, results from a 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 the rivastigmine tartrate trials was a structured instrument based on a comprehensive evaluation at baseline and subsequent time-points of 3 domains: patient cognition, behavior and functioning, including assessment of activities of daily living.
It represents the assessment of a skilled clinician using validated scales based on his/her observation at interviews conducted separately with the patient and the caregiver familiar with the behavior of the patient over the interval rated. The CIBIC-Plus is scored as a 7-point categorical rating, ranging from a score of 1, indicating "markedly improved," to a score of 4, indicating "no change" to a score of 7, indicating "marked worsening." The CIBIC-Plus has not been systematically compared directly to assessments not using information from caregivers or other global methods. U.S. 26-Week Study of Rivastigmine Tartrate in Mild-to-Moderate Alzheimer’s Disease (Study 1) In a study of 26 weeks duration, 699 patients were randomized to either a dose range of 1 mg to 4 mg or 6 mg to 12 mg of rivastigmine tartrate per day or to placebo, each given in divided doses.
The 26-week study was divided into a 12-week forced-dose titration phase and a 14-week maintenance phase. The patients in the active treatment arms of the study were maintained at their highest tolerated dose within the respective range. Figure 1 illustrates the time course for the change from baseline in ADAS-cog scores for all 3 dose groups over the 26 weeks of the study.
At 26 weeks of treatment, the mean differences in the ADAS-cog change scores for the rivastigmine tartrate-treated patients compared to the patients on placebo were 1.9 and 4.9 units for the 1 mg to 4 mg and 6 mg to 12 mg treatments, respectively. Both treatments were statistically significantly superior to placebo and the 6 mg to 12 mg per day range was significantly superior to the 1 mg to 4 mg per day range. Figure 1: Time-course of the Change from Baseline in ADAS-cog Score for Patients Completing 26 Weeks of Treatment in Study 1 Figure 2 illustrates the cumulative percentages of patients from each of the 3 treatment groups who had attained at least 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 rivastigmine tartrate and placebo have a wide range of responses, but that the rivastigmine tartrate groups are more likely to show the 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, respectively.
Figure 2: Cumulative Percentage of Patients Completing 26 Weeks of Double-blind Treatment with Specified Changes from Baseline ADAS-cog Scores. The Percentages of Randomized Patients who Completed the Study were: Placebo 84%, 1 mg to 4 mg 85%, and 6 mg to 12 mg 65%. Figure 3 is a histogram of the frequency distribution of CIBIC-Plus scores attained by patients assigned to each of the 3 treatment groups who completed 26 weeks of treatment. The mean rivastigmine tartrate-placebo differences for these groups of patients in the mean rating of change from baseline were 0.32 units and 0.35 units for 1 mg to 4 mg and 6 mg to 12 mg of rivastigmine tartrate, respectively.
The mean ratings for the 6 mg to 12 mg per day and 1 mg to 4 mg per day groups were statistically significantly superior to placebo. The differences between the 6 mg to 12 mg per day and the 1 mg to 4 mg per day groups were statistically significant. Figure 3: Frequency Distribution of CIBIC-Plus Scores at Week 26 in Study 1 Global 26-Week Study in Mild-to-Moderate Alzheimer’s Disease (Study 2) In a second study of 26 weeks duration, 725 patients were randomized to either a dose range of 1 mg to 4 mg or 6 mg to 12 mg of rivastigmine tartrate per day or to placebo, each given in divided doses.
The 26-week study was divided into a 12-week forced-dose titration phase and a 14-week maintenance phase. The patients in the active treatment arms of the study were maintained at their highest tolerated dose within the respective range. Figure 4 illustrates the time course for the change from baseline in ADAS-cog scores for all 3 dose groups over the 26 weeks of the study.
At 26 weeks of treatment, the mean differences in the ADAS-cog change scores for the rivastigmine tartrate-treated patients compared to the patients on placebo were 0.2 and 2.6 units for the 1 mg to 4 mg and 6 mg to 12 mg treatments, respectively. The 6 mg to 12 mg per day group was statistically significantly superior to placebo, as well as to the 1 mg to 4 mg/day group. The difference between the 1 mg to 4 mg per day group and placebo was not statistically significant.
Figure 4: Time-course of the Change from Baseline in ADAS-cog Score for Patients Completing 26 Weeks of Treatment Figure 5 illustrates the cumulative percentages of patients from each of the 3 treatment groups who had attained at least the measure of improvement in ADAS-cog score shown on the x-axis. Similar to the U.S. 26-week study, the curves demonstrate that both patients assigned to rivastigmine tartrate and placebo have a wide range of responses, but that the 6 mg to 12 mg per day rivastigmine tartrate group is more likely to show the greater improvements. Figure 5: Cumulative Percentage of Patients Completing 26 Weeks of Double-blind Treatment with Specified Changes from Baseline ADAS-cog Scores.
The Percentages of Randomized Patients who Completed the Study were: Placebo 87%, 1 mg to 4 mg 86%, and 6 mg to 12 mg 67%. Figure 6 is a histogram of the frequency distribution of CIBIC-Plus scores attained by patients assigned to each of the 3 treatment groups who completed 26 weeks of treatment. The mean rivastigmine tartrate-placebo differences for these groups of patients for the mean rating of change from baseline were 0.14 units and 0.41 units for 1 mg to 4 mg and 6 mg to 12 mg of rivastigmine tartrate, respectively. The mean ratings for the 6 mg to 12 mg per day group were statistically significantly superior to placebo.
The comparison of the mean ratings for the 1 mg to 4 mg per day group and placebo group was not statistically significant. Figure 6: Frequency Distribution of CIBIC-Plus Scores at Week 26 in Study 2 U.S. Fixed-Dose Study in Mild-to-Moderate Alzheimer’s Disease (Study 3) In a study of 26 weeks duration, 702 patients were randomized to doses of 3 mg, 6 mg, or 9 mg per day of rivastigmine tartrate or to placebo, each given in divided doses. The fixed-dose study design, which included a 12-week forced-dose titration phase and a 14-week maintenance phase, led to a high dropout rate in the 9 mg per day group because of poor tolerability.
At 26 weeks of treatment, significant differences were observed for the ADAS-cog mean change from baseline for the 9 mg per day and 6 mg per day groups, compared to placebo. No significant differences were observed between any of the rivastigmine tartrate-dose groups and placebo for the analysis of the CIBIC-Plus mean rating of change. Although no significant differences were observed between rivastigmine tartrate treatment groups, there was a trend toward numerical superiority with higher doses.
Mild-to-Moderate Parkinson’s Disease Dementia International 24-Week Study (Study 4) The effectiveness of rivastigmine tartrate as a treatment for dementia associated with Parkinson’s disease is demonstrated by the results of 1 randomized, double-blind, placebo-controlled clinical investigation in patients with mild-to-moderate dementia, with onset at least 2 years after the initial diagnosis of idiopathic Parkinson’s disease. The diagnosis of idiopathic Parkinson’s disease was based on the United Kingdom Parkinson’s Disease Society Brain Bank clinical criteria. The diagnosis of dementia was based on the criteria stipulated under the DSM-IV category “Dementia Due To Other General Medical Condition” (code 294.1x), but patients were not required to have a distinctive pattern of cognitive deficits as part of the dementia.
Alternate causes of dementia were excluded by clinical history, physical and neurological examination, brain imaging, and relevant blood tests. Patients enrolled in the study had a MMSE score greater than or equal to 10 and less than or equal to 24 at entry. The mean age of patients participating in this trial was 72.7 years with a range of 50 to 91 years.
Approximately, 35.1% of patients were women and 64.9% of patients were men. The racial distribution was 99.6% Caucasian and other races 0.4%. This study used a dual outcome assessment strategy to evaluate the effectiveness of rivastigmine tartrate. The ability of rivastigmine tartrate to improve cognitive performance was assessed with the ADAS-cog.
The ability of rivastigmine tartrate to produce an overall clinical effect was assessed using the Alzheimer’s Disease Cooperative Study – Clinician’s Global Impression of Change (ADCS-CGIC). The ADCS-CGIC is a more standardized form of CIBIC-Plus and is also scored as a 7-point categorical rating, ranging from a score of 1, indicating “markedly improved,” to a score of 4, indicating “no change” to a score of 7, indicating “marked worsening”. In this study, 541 patients were randomized to a dose range of 3 mg to 12 mg of rivastigmine tartrate per day or to placebo in a ratio of 2:1, given in divided doses. The 24-week study was divided into a 16-week titration phase and an 8-week maintenance phase. The patients in the active treatment arm of the study were maintained at their highest tolerated dose within the specified dose range.
Figure 7 illustrates the time course for the change from baseline in ADAS-cog scores for both treatment groups over the 24-week study. At 24 weeks of treatment, the mean difference in the ADAS-cog change scores for the rivastigmine tartrate-treated patients compared to the patients on placebo was 3.8 points. This treatment difference was statistically significant in favor of rivastigmine tartrate when compared to placebo.
Figure 7: Time Course of the Change from Baseline in ADAS-cog Score for Patients Completing 24 Weeks of Treatment in Study 4 Figure 8 is a histogram of the distribution of patients’ scores on the ADCS-CGIC (Alzheimer’s Disease Cooperative Study - Clinician’s Global Impression of Change) at 24 weeks. The mean difference in change scores between the rivastigmine tartrate and placebo groups from baseline was 0.5 points. This difference was statistically significant in favor of rivastigmine tartrate treatment.
Figure 8: Distribution of ADCS-CGIC Scores for Patients Completing 24 Weeks of Treatment in Study 4 Patients' age, gender, or race did not predict clinical outcome of rivastigmine tartrate treatment. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8
Drug information sourced from the FDA. This content is for informational purposes only and does not constitute medical advice. Consult a healthcare professional before making any medication decisions.
Ready to save on Rivastigmine?
Compare prescription prices at over 70,000 pharmacies and start saving today—no enrollment required.
Compare Rivastigmine Prices