MIRAPEX Tablet Ref.[10884] Active ingredients: Pramipexole

5.1 Falling Asleep During Activities of Daily Living and Somnolence

Patients treated with pramipexole have reported falling asleep while engaged in activities of daily living, including the operation of motor vehicles which sometimes resulted in accidents. Although many of these patients reported somnolence while on pramipexole tablets, some perceived that they had no warning signs (sleep attack) such as excessive drowsiness, and believed that they were alert immediately prior to the event. Some of these events had been reported as late as one year after the initiation of treatment.

Somnolence is a common occurrence in patients receiving pramipexole at doses above 1.5 mg/day (0.5 mg three times a day) for Parkinson’s disease. In controlled clinical trials in RLS, patients treated with MIRAPEX tablets at doses of 0.25-0.75 mg once a day, the incidence of somnolence was 6% compared to an incidence of 3% for placebo-treated patients [see Adverse Reactions (6.1)]. It has been reported that falling asleep while engaged in activities of daily living usually occurs in a setting of pre-existing somnolence, although patients may not give such a history. For this reason, prescribers should reassess patients for drowsiness or sleepiness, especially since some of the events occur well after the start of treatment. Prescribers should also be aware that patients may not acknowledge drowsiness or sleepiness until directly questioned about drowsiness or sleepiness during specific activities.

Before initiating treatment with MIRAPEX tablets, advise patients of the potential to develop drowsiness and specifically ask about factors that may increase the risk for somnolence with MIRAPEX tablets such as the use of concomitant sedating medications or alcohol, the presence of sleep disorders, and concomitant medications that increase pramipexole plasma levels (e.g., cimetidine) [see Clinical Pharmacology (12.3)]. If a patient develops significant daytime sleepiness or episodes of falling asleep during activities that require active participation (e.g., conversations, eating, etc.), MIRAPEX tablets should ordinarily be discontinued. If a decision is made to continue MIRAPEX tablets, advise patients not to drive and to avoid other potentially dangerous activities that might result in harm if the patients become somnolent. While dose reduction reduces the degree of somnolence, there is insufficient information to establish that dose reduction will eliminate episodes of falling asleep while engaged in activities of daily living.

5.2 Symptomatic Orthostatic Hypotension

Dopamine agonists, in clinical studies and clinical experience, appear to impair the systemic regulation of blood pressure, with resulting orthostatic hypotension, especially during dose escalation. Parkinson’s disease patients, in addition, appear to have an impaired capacity to respond to an orthostatic challenge. For these reasons, both Parkinson’s disease patients and RLS patients being treated with dopaminergic agonists ordinarily require careful monitoring for signs and symptoms of orthostatic hypotension, especially during dose escalation, and should be informed of this risk.

In clinical trials of pramipexole, however, and despite clear orthostatic effects in normal volunteers, the reported incidence of clinically significant orthostatic hypotension was not greater among those assigned to pramipexole tablets than among those assigned to placebo. This result, especially with the higher doses used in Parkinson’s disease, is clearly unexpected in light of the previous experience with the risks of dopamine agonist therapy.

While this finding could reflect a unique property of pramipexole, it might also be explained by the conditions of the study and the nature of the population enrolled in the clinical trials. Patients were very carefully titrated, and patients with active cardiovascular disease or significant orthostatic hypotension at baseline were excluded. Also, clinical trials in patients with RLS did not incorporate orthostatic challenges with intensive blood pressure monitoring done in close temporal proximity to dosing.

5.3 Impulse Control/Compulsive Behaviors

Case reports and the results of a cross-sectional study suggest that patients can experience intense urges to gamble, increased sexual urges, intense urges to spend money uncontrollably, binge eating, and/or other intense urges and the inability to control these urges while taking one or more of the medications, including MIRAPEX, that increase central dopaminergic tone. In some cases, although not all, these urges were reported to have stopped when the dose was reduced or the medication was discontinued. Because patients may not recognize these behaviors as abnormal, it is important for prescribers to specifically ask patients or their caregivers about the development of new or increased gambling urges, sexual urges, uncontrolled spending or other urges while being treated with MIRAPEX for Parkinson’s disease or RLS. Physicians should consider dose reduction or stopping the medication if a patient develops such urges while taking MIRAPEX.

5.4 Hallucinations and Psychotic-like Behavior

In the three double-blind, placebo-controlled trials in early Parkinson’s disease, hallucinations were observed in 9% (35 of 388) of patients receiving MIRAPEX tablets, compared with 2.6% (6 of 235) of patients receiving placebo. In the four double-blind, placebo-controlled trials in advanced Parkinson’s disease, where patients received MIRAPEX tablets and concomitant levodopa, hallucinations were observed in 16.5% (43 of 260) of patients receiving MIRAPEX tablets compared with 3.8% (10 of 264) of patients receiving placebo. Hallucinations were of sufficient severity to cause discontinuation of treatment in 3.1% of the early Parkinson’s disease patients and 2.7% of the advanced Parkinson’s disease patients compared with about 0.4% of placebo patients in both populations.

Age appears to increase the risk of hallucinations attributable to pramipexole. In the early Parkinson’s disease patients, the risk of hallucinations was 1.9 times greater than placebo in patients younger than 65 years and 6.8 times greater than placebo in patients older than 65 years. In the advanced Parkinson’s disease patients, the risk of hallucinations was 3.5 times greater than placebo in patients younger than 65 years and 5.2 times greater than placebo in patients older than 65 years.

Postmarketing reports with medications used to treat Parkinson’s disease or RLS, including MIRAPEX, indicate that patients may experience new or worsening mental status and behavioral changes, which may be severe, including psychotic-like behavior during treatment with MIRAPEX or after starting or increasing the dose of MIRAPEX. Other drugs prescribed to improve the symptoms of Parkinson’s disease or RLS can have similar effects on thinking and behavior. This abnormal thinking and behavior can consist of one or more of a variety of manifestations including paranoid ideation, delusions, hallucinations, confusion, psychotic-like behavior, symptoms of mania (e.g., insomnia, psychomotor agitation), disorientation, aggressive behavior, agitation, and delirium.

Patients with a major psychotic disorder should ordinarily not be treated with dopamine agonists, including MIRAPEX, because of the risk of exacerbating the psychosis. In addition, certain medications used to treat psychosis may exacerbate the symptoms of Parkinson’s disease and may decrease the effectiveness of MIRAPEX [see Drug Interactions (7.1)].

In the RLS clinical trials, one pramipexole-treated patient (of 889) reported hallucinations; this patient discontinued treatment and the symptoms resolved.

5.5 Dyskinesia

MIRAPEX tablets may cause or exacerbate preexisting dyskinesia.

5.6 Postural Deformity

Postural deformities, including antecollis, camptocormia (Bent Spine Syndrome), and pleurothotonus (Pisa Syndrome), have been reported in patients after starting or increasing the dose of MIRAPEX. Postural deformity may occur several months after starting treatment or increasing the dose. Reducing the dose or discontinuing MIRAPEX has been reported to improve postural deformity in some patients, and should be considered if postural deformity occurs.

5.7 Renal Impairment

Since pramipexole is eliminated through the kidneys, caution should be exercised when prescribing MIRAPEX tablets to patients with renal impairment [see Dosage and Administration (2.3), Use in Specific Populations (8.6), and Clinical Pharmacology (12.3)].

5.8 Rhabdomyolysis

A single case of rhabdomyolysis occurred in a 49-year-old male with advanced Parkinson’s disease treated with MIRAPEX tablets. The patient was hospitalized with an elevated CPK (10,631 IU/L). The symptoms resolved with discontinuation of the medication.

Advise patients to contact a physician if they experience any unexplained muscle pain, tenderness, or weakness, as these may be symptoms of rhabdomyolysis.

5.9 Retinal Pathology

Human Data

A two-year open-label, randomized, parallel-group safety study of retinal deterioration and vision compared MIRAPEX tablets and immediate-release ropinirole. Two hundred thirty four Parkinson’s disease patients (115 on pramipexole, mean dose 3.0 mg/day and 119 on ropinirole, mean dose 9.5 mg/day) were evaluated using a panel of clinical ophthalmological assessments. Of 234 patients who were evaluable, 196 had been treated for two years and 29 were judged to have developed clinical abnormalities that were considered meaningful (19 patients in each treatment arm had received treatment for less than two years). There was no statistical difference in retinal deterioration between the treatment arms; however, the study was only capable of detecting a very large difference between treatments. In addition, because the study did not include an untreated comparison group (placebo treated), it is unknown whether the findings reported in patients treated with either drug are greater than the background rate in an aging population.

Animal Data

Pathologic changes (degeneration and loss of photoreceptor cells) were observed in the retina of albino rats in the 2-year carcinogenicity study. While retinal degeneration was not diagnosed in pigmented rats treated for 2 years, a thinning in the outer nuclear layer of the retina was slightly greater in rats given drug compared with controls. Evaluation of the retinas of albino mice, monkeys, and minipigs did not reveal similar changes. The potential significance of this effect in humans has not been established, but cannot be disregarded because disruption of a mechanism that is universally present in vertebrates (i.e., disk shedding) may be involved [see Nonclinical Toxicology (13.2)].

5.10 Events Reported with Dopaminergic Therapy

Although the events enumerated below may not have been reported in association with the use of pramipexole in its development program, they are associated with the use of other dopaminergic drugs. The expected incidence of these events, however, is so low that even if pramipexole caused these events at rates similar to those attributable to other dopaminergic therapies, it would be unlikely that even a single case would have occurred in a cohort of the size exposed to pramipexole in studies to date.

Hyperpyrexia and Confusion

Although not reported with pramipexole in the clinical development program, a symptom complex resembling the neuroleptic malignant syndrome (characterized by elevated temperature, muscular rigidity, altered consciousness, and autonomic instability), with no other obvious etiology, has been reported in association with rapid dose reduction, withdrawal of, or changes in dopaminergic therapy. If possible, avoid sudden discontinuation or rapid dose reduction in patients taking MIRAPEX tablets. If the decision is made to discontinue MIRAPEX tablets, the dose should be tapered to reduce the risk of hyperpyrexia and confusion [see Dosage and Administration (2.2)].

Fibrotic Complications

Cases of retroperitoneal fibrosis, pulmonary infiltrates, pleural effusion, pleural thickening, pericarditis, and cardiac valvulopathy have been reported in patients treated with ergot-derived dopaminergic agents. While these complications may resolve when the drug is discontinued, complete resolution does not always occur.

Although these adverse events are believed to be related to the ergoline structure of these compounds, whether other, nonergot-derived dopamine agonists can cause them is unknown.

Cases of possible fibrotic complications, including peritoneal fibrosis, pleural fibrosis, and pulmonary fibrosis have been reported in the post marketing experience with MIRAPEX tablets. While the evidence is not sufficient to establish a causal relationship between MIRAPEX tablets and these fibrotic complications, a contribution of MIRAPEX tablets cannot be completely ruled out.

Rebound and Augmentation in RLS

Reports in the literature indicate treatment of RLS with dopaminergic medications can result in rebound: a worsening of symptoms following treatment cessation with greater intensity than described before starting treatment. In a 26 week placebo controlled clinical trial in patients with RLS, a worsening of symptoms scores (IRLS) beyond their untreated baseline levels was reported more frequently by patients suddenly withdrawn from MIRAPEX (up to 0.75 mg once daily) compared to the group assigned to placebo (10% vs. 2%, respectively). The worsening of RLS symptoms was considered generally mild.

Augmentation has also been described during therapy for RLS. Augmentation refers to the earlier onset of symptoms in the evening (or even the afternoon), increase in symptoms, and spread of symptoms to involve other extremities. In a 26 week placebo controlled clinical trial in patients with RLS, augmentation was reported with greater frequency by patients treated with MIRAPEX (up to 0.75 mg once daily) compared to patients who received placebo (12% vs. 9%, respectively). The incidence of augmentation increased with increasing duration of exposure to MIRAPEX and to placebo.

The frequency and severity of augmentation and/or rebound after longer-term use of MIRAPEX tablets and the appropriate management of these events have not been adequately evaluated in controlled clinical trials.

The following adverse reactions are discussed in greater detail in other sections of the labeling:

• Falling Asleep During Activities of Daily Living and Somnolence [see Warnings and Precautions (5.1)].
• Symptomatic Orthostatic Hypotension [see Warnings and Precautions (5.2)].
• Impulse Control/Compulsive Behaviors [see Warnings and Precautions (5.3)].
• Hallucinations and Psychotic-like Behavior [see Warnings and Precautions (5.4)].
• Dyskinesia [see Warnings and Precautions (5.5)].
• Postural Deformity [see Warnings and Precautions (5.6)].
• Rhabdomyolysis [see Warnings and Precautions (5.8)].
• Retinal Pathology [see Warnings and Precautions (5.9)].
• Events Reported with Dopaminergic Therapy [see Warnings and Precautions (5.10)].

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 clinical practice.

Parkinson’s Disease

During the premarketing development of pramipexole, patients with either early or advanced Parkinson’s disease were enrolled in clinical trials. Apart from the severity and duration of their disease, the two populations differed in their use of concomitant levodopa therapy. Patients with early disease did not receive concomitant levodopa therapy during treatment with pramipexole; those with advanced Parkinson’s disease all received concomitant levodopa treatment. Because these two populations may have differential risks for various adverse reactions, this section will, in general, present adverse-reaction data for these two populations separately.

Because the controlled trials performed during premarketing development all used a titration design, with a resultant confounding of time and dose, it was impossible to adequately evaluate the effects of dose on the incidence of adverse reactions.

Early Parkinson’s Disease

In the three double-blind, placebo-controlled trials of patients with early Parkinson’s disease, the most common adverse reactions (>5%) that were numerically more frequent in the group treated with MIRAPEX tablets were nausea, dizziness, somnolence, insomnia, constipation, asthenia, and hallucinations.

Approximately 12% of 388 patients with early Parkinson’s disease and treated with MIRAPEX tablets who participated in the double-blind, placebo-controlled trials discontinued treatment due to adverse reactions compared with 11% of 235 patients who received placebo. The adverse reactions most commonly causing discontinuation of treatment were related to the nervous system (hallucinations [3.1% on MIRAPEX tablets vs 0.4% on placebo]; dizziness [2.1% on MIRAPEX tablets vs 1% on placebo]; somnolence [1.6% on MIRAPEX tablets vs 0% on placebo]; headache and confusion [1.3% and 1.0%, respectively, on MIRAPEX tablets vs 0% on placebo]) and gastrointestinal system (nausea [2.1% on MIRAPEX tablets vs 0.4% on placebo]).

Adverse-reaction Incidence in Controlled Clinical Studies in Early Parkinson’s Disease: Table 4 lists adverse reactions that occurred in the double-blind, placebo-controlled studies in early Parkinson’s disease that were reported by ≥1% of patients treated with MIRAPEX tablets and were numerically more frequent than in the placebo group. In these studies, patients did not receive concomitant levodopa.

Table 4. Adverse-Reactions in Pooled Double-Blind, Placebo-Controlled Trials with MIRAPEX in Early Parkinson’s Disease:

In a fixed-dose study in early Parkinson’s disease, occurrence of the following reactions increased in frequency as the dose increased over the range from 1.5 mg/day to 6 mg/day: postural hypotension, nausea, constipation, somnolence, and amnesia. The frequency of these reactions was generally 2-fold greater than placebo for pramipexole doses greater than 3 mg/day. The incidence of somnolence with pramipexole at a dose of 1.5 mg/day was comparable to that reported for placebo.

Advanced Parkinson’s Disease

In the four double-blind, placebo-controlled trials of patients with advanced Parkinson’s disease, the most common adverse reactions (>5%) that were numerically more frequent in the group treated with MIRAPEX tablets and concomitant levodopa were postural (orthostatic) hypotension, dyskinesia, extrapyramidal syndrome, insomnia, dizziness, hallucinations, accidental injury, dream abnormalities, confusion, constipation, asthenia, somnolence, dystonia, gait abnormality, hypertonia, dry mouth, amnesia, and urinary frequency.

Approximately 12% of 260 patients with advanced Parkinson’s disease who received MIRAPEX tablets and concomitant levodopa in the double-blind, placebo-controlled trials discontinued treatment due to adverse reactions compared with 16% of 264 patients who received placebo and concomitant levodopa. The reactions most commonly causing discontinuation of treatment were related to the nervous system (hallucinations [2.7% on MIRAPEX tablets vs 0.4% on placebo]; dyskinesia [1.9% on MIRAPEX tablets vs 0.8% on placebo]) and cardiovascular system (postural [orthostatic] hypotension [2.3% on MIRAPEX tablets vs 1.1% on placebo]).

Adverse-reaction Incidence in Controlled Clinical Studies in Advanced Parkinson’s Disease: Table 5 lists adverse reactions that occurred in the double-blind, placebo-controlled studies in advanced Parkinson’s disease that were reported by ≥1% of patients treated with MIRAPEX tablets and were numerically more frequent than in the placebo group. In these studies, MIRAPEX tablets or placebo was administered to patients who were also receiving concomitant levodopa.

Table 5. Adverse-Reactions in Pooled Double-Blind, Placebo-Controlled Trials with MIRAPEX in Advanced Parkinson’s Disease:

Restless Legs Syndrome

MIRAPEX tablets for treatment of RLS have been evaluated for safety in 889 patients, including 427 treated for over six months and 75 for over one year.

The overall safety assessment focuses on the results of three double-blind, placebo-controlled trials, in which 575 patients with RLS were treated with MIRAPEX tablets for up to 12 weeks. The most common adverse reactions with MIRAPEX tablets in the treatment of RLS (observed in >5% of pramipexole-treated patients and at a rate at least twice that observed in placebo-treated patients) were nausea and somnolence. Occurrences of nausea and somnolence in clinical trials were generally mild and transient.

Approximately 7% of 575 patients treated with MIRAPEX tablets during the double-blind periods of three placebo-controlled trials discontinued treatment due to adverse reactions compared to 5% of 223 patients who received placebo. The adverse reaction most commonly causing discontinuation of treatment was nausea (1%).

Table 6 lists reactions that occurred in three double-blind, placebo-controlled studies in RLS patients that were reported by ≥2% of patients treated with MIRAPEX tablets and were numerically more frequent than in the placebo group.

Table 6. Adverse-Reactions in Pooled Double-Blind, Placebo-Controlled Trials with MIRAPEX in Restless Legs Syndrome:

Table 7 summarizes data for adverse reactions that appeared to be dose related in the 12-week fixed dose study.

Table 7. Dose-Related Adverse Reactions in a 12-Week Double-Blind, Placebo-Controlled Fixed Dose Study in Restless Legs Syndrome (Occurring in ≥5% of all Patients in the Treatment Phase):

Adverse Reactions: Relationship to Age, Gender, and Race

Among the adverse reactions in patients treated with MIRAPEX tablets, hallucination appeared to exhibit a positive relationship to age in patients with Parkinson’s disease. Although no gender-related differences were observed in Parkinson’s disease patients, nausea and fatigue, both generally transient, were more frequently reported by female than male RLS patients. Less than 4% of patients enrolled were non-Caucasian: therefore, an evaluation of adverse reactions related to race is not possible.

Laboratory Tests

During the development of MIRAPEX tablets, no systematic abnormalities on routine laboratory testing were noted.

In addition to the adverse events reported during clinical trials, the following adverse reactions have been identified during post-approval use of MIRAPEX tablets, primarily in Parkinson’s disease patients. 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. Decisions to include these reactions in labeling are typically based on one or more of the following factors: (1) seriousness of the reaction, (2) frequency of reporting, or (3) strength of causal connection to pramipexole tablets.

Cardiac Disorders: cardiac failure

Gastrointestinal Disorders: vomiting

Metabolism and Nutrition Disorders: syndrome of inappropriate antidiuretic hormone secretion (SIADH), weight increase

Musculoskeletal and Connective Tissue Disorders: postural deformity [see Warnings and Precautions (5.6)]

Nervous System Disorders: syncope

Skin and Subcutaneous Tissue Disorders: skin reactions (including erythema, rash, pruritus, urticaria)

7.1 Dopamine Antagonists

Since pramipexole is a dopamine agonist, it is possible that dopamine antagonists, such as the neuroleptics (phenothiazines, butyrophenones, thioxanthenes) or metoclopramide, may diminish the effectiveness of MIRAPEX tablets.

Risk Summary

There are no adequate data on the developmental risk associated with the use of MIRAPEX in pregnant women. No adverse developmental effects were observed in animal studies in which pramipexole was administered to rabbits during pregnancy. Effects on embryofetal development could not be adequately assessed in pregnant rats; however, postnatal growth was inhibited at clinically relevant exposures [see Data].

In the U.S. general population, the estimated background risk of major birth defects and of miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown.

Data

Animal Data

Oral administration of pramipexole (0.1, 0.5, or 1.5 mg/kg/day) to pregnant rats during the period of organogenesis resulted in a high incidence of total resorption of embryos at the highest dose tested. This increase in embryolethality is thought to result from the prolactin-lowering effect of pramipexole; prolactin is necessary for implantation and maintenance of early pregnancy in rats but not in rabbits or humans. Because of pregnancy disruption and early embryonic loss in this study, the teratogenic potential of pramipexole could not be adequately assessed in rats. The highest no-effect dose for embryolethality in rats was associated with maternal plasma drug exposures (AUC) approximately equal to those in humans receiving the maximum recommended human dose (MRHD) of 4.5 mg/day. There were no adverse effects on embryo-fetal development following oral administration of pramipexole (0.1, 1, or 10 mg/kg/day) to pregnant rabbits during organogenesis (plasma AUC up to approximately 70 times that in humans at the MRHD). Postnatal growth was inhibited in the offspring of rats treated with pramipexole (0.1, 0.5, or 1.5 mg/kg/day) during the latter part of pregnancy and throughout lactation. The no-effect dose for adverse effects on offspring growth (0.1 mg/kg/day) was associated with maternal plasma drug exposures lower than that in humans at the MRHD.

Risk Summary

There are no data on the presence of pramipexole in human milk, the effects of pramipexole on the breastfed infant, or the effects of pramipexole on milk production. However, inhibition of lactation is expected because pramipexole inhibits secretion of prolactin in humans. Pramipexole or metabolites, or both, are present in rat milk [see Data].

The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for MIRAPEX and any potential adverse effects on the breastfed infant from MIRAPEX or from the underlying maternal condition.

Data

In a study of radio-labeled pramipexole, pramipexole or metabolites, or both, were present in rat milk at concentrations three to six times higher than those in maternal plasma.

Safety and effectiveness of MIRAPEX in pediatric patients has not been established.

Pramipexole total oral clearance is approximately 30% lower in subjects older than 65 years compared with younger subjects, because of a decline in pramipexole renal clearance due to an age-related reduction in renal function. This resulted in an increase in elimination half-life from approximately 8.5 hours to 12 hours.

In clinical studies with Parkinson’s disease patients, 38.7% of patients were older than 65 years. There were no apparent differences in efficacy or safety between older and younger patients, except that the relative risk of hallucination associated with the use of MIRAPEX tablets was increased in the elderly.

In clinical studies with RLS patients, 22% of patients were at least 65 years old. There were no apparent differences in efficacy or safety between older and younger patients.

The elimination of pramipexole is dependent on renal function. Pramipexole clearance is extremely low in dialysis patients, as a negligible amount of pramipexole is removed by dialysis. Caution should be exercised when administering MIRAPEX tablets to patients with renal disease [see Dosage and Administration (2.2), Warnings and Precautions (5.7), and Clinical Pharmacology (12.3)].