2.1 Dosing Information

The recommended starting dosage of XADAGO is 50 mg administered orally once daily (at the same time of day), without regard to meals. After two weeks, the dosage may be increased to 100 mg once daily, based on individual need and tolerability.

Daily dosages of XADAGO above 100 mg have not been shown to provide additional benefit, and higher dosages increase the risk for adverse reactions. XADAGO has been shown to be effective only in combination with levodopa/carbidopa [see Indications and Usage (1)] .

If a dose is missed, the next dose should be taken at the same time the next day.

XADAGO 100 mg should be tapered by decreasing the dose to 50 mg for one week before stopping [see Warnings and Precautions (5.7)] .

2.2 Dosing in Patients with Hepatic Impairment

In patients with moderate hepatic impairment (Child-Pugh B: 7-9), the maximum recommended dosage of XADAGO is 50 mg orally once daily. XADAGO is contraindicated in patients with severe hepatic impairment (Child-Pugh C: 10-15) [see Use in Specific Populations (8.6) and Clinical Pharmacology (12.3)] . If a patient taking 50 mg XADAGO progresses from moderate to severe hepatic impairment, discontinue XADAGO.

5.1 Hypertension

XADAGO may cause hypertension or exacerbate existing hypertension. In clinical trials, the incidence of hypertension was 7% for XADAGO 50 mg, 5% for XADAGO 100 mg, and 4% for placebo. Monitor patients for new onset hypertension or hypertension that is not adequately controlled after starting XADAGO. Medication adjustment may be necessary if elevation of blood pressure is sustained.

Monitor for hypertension if XADAGO is prescribed concomitantly with sympathomimetic medications, including prescription or nonprescription nasal, oral, and ophthalmic decongestants and cold remedies [see Drug Interactions (7.5)] .

XADAGO is a selective inhibitor of MAO-B at the recommended dosages of 50 mg or 100 mg daily. Selectivity for inhibiting MAO-B decreases above the recommended daily dosages [see Clinical Pharmacology (12.2)] . Therefore, XADAGO should not be used at daily dosages exceeding those recommended because of the risks of hypertension, exacerbation of existing hypertension, or hypertensive crisis.

Dietary tyramine restriction is not required during treatment with recommended doses of XADAGO. However, use with certain foods that contain very high amounts (i.e., more than 150 mg) of tyramine could cause severe hypertension, resulting from an increased sensitivity to tyramine in patients taking recommended dosages of XADAGO, and patients should be advised to avoid such foods.

Isoniazid has some monoamine oxidase inhibiting activity. Monitor for hypertension and reaction to dietary tyramine in patients treated concomitantly with isoniazid and XADAGO [see Drug Interactions (7.1, 7.6)] .

5.2 Serotonin Syndrome

The development of a potentially life-threatening serotonin syndrome has been reported in patients on concomitant treatment with MAOIs (including selective MAO-B inhibitors), serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, tetracyclic antidepressants, triazolopyridine antidepressants, cyclobenzaprine, opioid drugs (e.g., meperidine and meperidine derivatives, propoxyphene, tramadol), and methylphenidate, amphetamine, and their derivatives. Concomitant use of XADAGO with these drugs is contraindicated.

In clinical trials, serotonin syndrome was reported in a patient treated with XADAGO and a selective serotonin reuptake inhibitor (SSRI). Use the lowest effective dose of SSRIs in patients treated with concomitant XADAGO.

Serotonin syndrome symptoms may include mental status changes (e.g., agitation, hallucinations, delirium, and coma), autonomic instability (e.g., tachycardia, labile blood pressure, dizziness, diaphoresis, flushing, hyperthermia), neuromuscular symptoms (e.g., tremor, rigidity, myoclonus, hyperreflexia, incoordination), seizures, and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea).

5.3 Falling Asleep During Activities of Daily Living

Patients treated with dopaminergic medications have reported falling asleep while engaged in activities of daily living, including the operation of motor vehicles, which sometimes has resulted in accidents. Patients may not perceive warning signs, such as excessive drowsiness, or they may report feeling alert immediately prior to the event.

In clinical studies, sleep attacks/sudden onset of sleep were reported in patients treated with XADAGO 100 mg/day.

If a patient develops daytime sleepiness or episodes of falling asleep during activities that require full attention (e.g., driving a motor vehicle, conversations, eating), XADAGO should ordinarily be discontinued. If a decision is made to continue these patients on XADAGO, advise them to avoid driving and other potentially dangerous activities.

5.4 Dyskinesia

XADAGO may cause dyskinesia or exacerbate pre-existing dyskinesia.

In clinical trials, the incidence of dyskinesia was 21% for XADAGO 50 mg, 18% for XADAGO 100 mg, and 9% for placebo. There was a greater incidence of dyskinesia causing study discontinuation in patients treated with XADAGO 50 mg or 100 mg (1%), compared to placebo (0%) [see Adverse Reactions (6.1)] .

Reducing the patient's daily levodopa dosage or the dosage of another dopaminergic drug may mitigate dyskinesia.

5.5 Hallucinations / Psychotic Behavior

Patients with a major psychotic disorder should ordinarily not be treated with XADAGO because of the risk of exacerbating the psychosis with an increase in central dopaminergic tone. In addition, treatments for psychosis that antagonize the effects of dopaminergic medications may exacerbate the symptoms of PD [see Drug Interactions (7.7)] .

Consider dosage reduction or stopping the medication if a patient develops hallucinations or psychotic-like behaviors while taking XADAGO.

5.6 Impulse Control / Compulsive Behaviors

Patients can experience intense urges to gamble, increased sexual urges, intense urges to spend money, binge eating, and/or other intense urges, and the inability to control these urges while taking one or more of the medications, including XADAGO, that increase central dopaminergic tone. In some cases, 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 XADAGO. Consider dose reduction or stopping the medication if a patient develops such urges while taking XADAGO.

5.7 Withdrawal Emergent Hyperpyrexia and Confusion

A symptom complex resembling 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 drugs that increase central dopaminergic tone.

5.8 Retinal Pathology

Retinal degeneration and loss of photoreceptor cells were observed in albino and pigmented rats administered safinamide orally in toxicity studies of up to 6 months duration. In albino rats administered safinamide orally for two years, retinal scarring and cataracts were observed at all doses tested [see Nonclinical Toxicology (13.2)] .

Periodically monitor patients for visual changes in patients with a history of retinal/macular degeneration, uveitis, inherited retinal conditions, family history of hereditary retinal disease, albinism, retinitis pigmentosa, or any active retinopathy (e.g., diabetic retinopathy).

6.1 Clinical Trials Experience

Clinical trials are conducted under widely varying conditions; therefore, adverse reactions observed in the clinical trials of a drug cannot be directly compared to the incidence in the clinical trials of another drug and may not reflect the incidence observed in clinical practice.

6.2 Postmarketing Experience

The following adverse reactions have been identified during post-approval use of safinamide. 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.

Immune System Disorders: Hypersensitivity: A postmarketing report describes a patient who developed a hypersensitivity reaction consisting of swelling of the tongue and gingiva, dyspnea and skin rash. The symptoms resolved shortly after XADAGO was discontinued, but reappeared following rechallenge a month later.

Nervous System Disorders: Headache

7.1 MAO Inhibitors (MAOIs)

XADAGO is contraindicated for use with other drugs in the MAOIs class or other drugs that are potent inhibitors of monoamine oxidase (e.g., linezolid, an oxazolidinone antibacterial, which also has reversible nonselective MAO inhibition activity). Co-administration increases the risk of nonselective MAO inhibition, which may lead to hypertensive crisis [see Contraindications (4) and Warnings and Precautions (5.1)] . At least 14 days should elapse between discontinuation of XADAGO and initiation of treatment with other MAOIs.

Isoniazid has some monoamine oxidase inhibiting activity. Monitor for hypertension and reaction to dietary tyramine in patients treated concomitantly with isoniazid and XADAGO.

7.2 Opioid Drugs

Because serious, sometimes fatal reactions have been precipitated with concomitant use of opioid drugs (e.g., meperidine and its derivatives, methadone, propoxyphene, or tramadol) and MAOIs, including selective MAO-B inhibitors, concomitant use of these drugs is contraindicated [see Warnings and Precautions (5.2)] . At least 14 days should elapse between discontinuation of XADAGO and initiation of treatment with these drugs.

7.3 Serotonergic Drugs

Concomitant use of XADAGO with SNRIs; triazolopyridine, tricyclic or tetracyclic antidepressants; cyclobenzaprine (a skeletal muscle relaxant that is a tricyclic antidepressant derivative); or St. John's wort is contraindicated [see Warnings and Precautions (5.2)] . At least 14 days should elapse between discontinuation of XADAGO and initiation of treatment with these drugs.

Monitor patients for symptoms of serotonin syndrome if SSRIs are used by patients treated with XADAGO [see Warnings and Precautions (5.2)] .

7.4 Dextromethorphan

The combination of MAOIs and dextromethorphan has been reported to cause episodes of psychosis or bizarre behavior. Therefore, in view of XADAGO's MAO inhibitory activity, dextromethorphan is contraindicated for use with XADAGO.

7.5 Sympathomimetic Medications

Severe hypertensive reactions have followed the administration of sympathomimetics and nonselective MAOIs. Hypertensive crisis has been reported in patients taking the recommended doses of selective MAO-B inhibitors and sympathomimetic medications. Concomitant use of XADAGO with methylphenidate, amphetamine, and their derivatives is contraindicated [see Warnings and Precautions (5.1, 5.2)] .

Monitor patients for hypertension if XADAGO is prescribed concomitantly with prescription or nonprescription sympathomimetic medications, including nasal, oral, or ophthalmic decongestants and cold remedies [see Warnings and Precautions (5.1)] .

7.6 Tyramine

MAO in the gastrointestinal tract and liver (primarily type A) provides protection from exogenous amines (e.g., tyramine). If tyramine were absorbed intact, it could lead to severe hypertension, including hypertensive crisis. Aged, fermented, cured, smoked, and pickled foods containing large amounts of exogenous amines (e.g., aged cheese, pickled herring) may cause release of norepinephrine resulting in a rise in blood pressure (Tyramine Reaction). Patients should be advised to avoid foods containing a large amount of tyramine while taking recommended doses of XADAGO [see Warnings and Precautions (5.1)] .

Selectivity for inhibiting MAO-B decreases in a dose-related manner above the highest recommended daily dosage, which may increase the risk for hypertension [see Clinical Pharmacology (12.2)] . In addition, isoniazid has some monoamine oxidase inhibiting activity. Monitor for hypertension and reaction to dietary tyramine in patients treated with isoniazid and XADAGO [see Warnings and Precautions (5.1)] .

7.7 Dopaminergic Antagonists

Dopamine antagonists, such as antipsychotics or metoclopramide, may decrease the effectiveness of XADAGO and exacerbate the symptoms of PD.

8.1 Pregnancy

8.2 Lactation

8.4 Pediatric Use

Safety and effectiveness in pediatric patients have not been established.

8.5 Geriatric Use

Of the 1516 subjects exposed to XADAGO in clinical studies, 38% were 65 and over, while 4% were 75 and over. No overall differences in safety or effectiveness were observed between these patients and younger patients, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.

8.6 Hepatic Impairment

XADAGO plasma concentrations are increased in patients with hepatic impairment [see Clinical Pharmacology (12.3)] .

In patients with moderate hepatic impairment (Child-Pugh B: 7-9), the maximum recommended dosage of XADAGO is 50 mg once daily [see Dosage and Administration (2.2)] . XADAGO has not been studied in patients with severe hepatic impairment (Child-Pugh C: 10-15), and is contraindicated in these patients. If patients progress from moderate to severe hepatic impairment, treatment with XADAGO should be stopped.

12.1 Mechanism of Action

The precise mechanism by which XADAGO exerts its therapeutic effects in PD is unknown. XADAGO is an inhibitor of monoamine oxidase B (MAO-B). Inhibition of MAO-B activity, by blocking the catabolism of dopamine, is thought to result in an increase in dopamine levels and a subsequent increase in dopaminergic activity in the brain.

12.2 Pharmacodynamics

XADAGO inhibits monoamine oxidase B (MAO-B), with more than 1000-fold selectivity over MAO-A. In clinical studies, complete inhibition (>90%) of MAO-B was measured at doses > 20 mg.

12.3 Pharmacokinetics

Pharmacokinetics of safinamide is linear over a range of 50 mg to 300 mg (3 times the maximum recommended daily dose). Steady state is reached within 5 to 6 days.

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

13.2 Animal Toxicology and/or Pharmacology

14.1 Adjunctive Treatment in Patients with Parkinson's Disease Experiencing OFF Time on a Stable Dose of Levodopa.

Two double-blind, placebo-controlled, multi-national, 24-week studies (Study 1 and Study 2) were conducted in PD patients experiencing "OFF" Time during treatment with carbidopa/levodopa and other PD medications, e.g., dopamine agonists, catechol-O-methyl transferase (COMT) inhibitors, anticholinergics, and/or amantadine. In both studies, the primary measure of effectiveness was the change from baseline in total daily "ON" Time without troublesome dyskinesia (i.e., "ON" Time without dyskinesia plus "ON" Time with non-troublesome dyskinesia), based on 18-hour diaries completed by patients for at least 3 days before each of the scheduled visits. Secondary endpoints included "OFF" Time during the diary period and reduction in Unified PD Rating Scale (UPDRS) Part III (motor examination).

In Study 1, patients (n=645) were randomized equally to treatment with XADAGO 50 mg/day (n=217 patients), XADAGO 100 mg/day (n=216 patients), or placebo (n=212 patients), and had at least one post-baseline assessment of "ON" Time.

The percentages of patients taking stable doses of other classes of PD medications, in addition to levodopa/decarboxylase inhibitor, were: dopamine agonists (61%), COMT inhibitors (24%), anticholinergics (37%), and amantadine (14%). Use of MAOIs was prohibited. The average daily dosage of levodopa was 630 mg. The mean duration of PD was approximately 8 years.

In Study 1, XADAGO 50 mg/day and 100 mg/day significantly increased "ON" Time compared to placebo (Table 2). The increase in "ON" Time without troublesome dyskinesia was accompanied by a similar significant reduction in "OFF" Time and a reduction in Unified PD Rating Scale Part III (UPDRS III) scores assessed during "ON" Time (Table 3). Improvement in "ON" Time occurred without an increase in troublesome dyskinesia.

The effect of XADAGO 100 mg on "ON" Time was only slightly numerically greater than the effect of XADAGO 50 mg. In addition, the time course of improvement in total daily "ON" Time was similar between both doses (Figure 1). The time course of improvement in total daily "ON" Time showed numerically greater improvement with both XADAGO 50 mg and 100 mg compared to placebo, at all post-baseline timepoints (Figure 1).

Figure 1: Mean Change from Baseline in Total Daily "ON" Time by Week and Treatment in Study 1

Figure 2 shows the empirical cumulative distribution functions (CDF) for the change from baseline to Week 24 in total daily "ON" Time in Study 1. The cumulative percentage of patients with a change in "ON" Time was similar for the XADAGO 50 mg and 100 mg groups. The cumulative percentage of patients with an increase in "ON" Time is higher for both XADAGO 50 mg and 100 mg treated patients than for placebo patients.

Figure 2: Study 1 Empirical Cumulative Distribution Functions (CDF) for the Change from Baseline to Week 24 in Total Daily "ON" Time

Patients who dropped out of the study because of an adverse reaction, lack of efficacy, non-compliance, or withdrawal of consent were treated as treatment failures and assumed to have the smallest change from baseline among all patients. The failure rates are 6.1%, 5.6%, and 6.9% for the placebo group, XADAGO 50 mg/day group, and XADAGO 100 mg/day group, respectively.

In Study 2, patients (n=549) were randomized to treatment with XADAGO 100 mg daily (n=274 patients) or placebo (n=275 patients) for up to 24 weeks. The percentages of patients taking stable doses of other classes of PD medication, in addition to levodopa/decarboxylase inhibitor, were: dopamine agonists (74%), COMT inhibitors (18%), anticholinergics (17%), and amantadine (30%). Use of MAOIs was prohibited. The average daily dosage of levodopa was 777 mg. The mean duration of PD was approximately 9 years.

In Study 2, XADAGO was significantly better than placebo for increasing "ON"Time (Table 4). The observed increase in "ON" Time without troublesome dyskinesia was accompanied by a reduction in "OFF" Time of similar magnitude and a reduction in UPDRS III score (assessed during "ON" Time). The time course of effect was similar to that showed in the above figure for Study 1. As in Study 1, the increase in "ON" Time without troublesome dyskinesia was accompanied by a similar significant reduction in "OFF" Time and a reduction in Unified PD Rating Scale Part III (UPDRS III) scores assessed during "ON" Time (Table 5).

The time course of improvement in total daily "ON" Time showed numerically greater improvement with XADAGO 100 mg compared to placebo at all post-baseline timepoints (Figure 3).

Figure 3: Mean Change from Baseline in Total Daily "ON" Time by Week and Treatment in Study 2

Figure 4 shows the empirical cumulative distribution functions (CDF) for the change from baseline to Week 24 in total daily "ON" Time in Study 2. The cumulative percentage of patients with an increase in "ON" Time treated with XADAGO 50 mg to 100 mg is higher than for placebo patients.

Figure 4: Study 2 Empirical Cumulative Distribution Functions (CDF) for the Change from Baseline to Week 24 in Total Daily "ON" Time

16.1 How Supplied

50 mg (orange to copper colored with metallic gloss, round film-coated, biconcave shaped tablet embossed with "50" on one side; approximately 7 mm in diameter).

100 mg (orange to copper colored with metallic gloss, round film-coated, biconcave shaped tablet embossed with "100" on one side; approximately 9 mm in diameter).

16.2 Storage and Handling

Store at 25°C (77°F); excursions permitted between 15°C to 30°C (59°F to 86°F) [see USP controlled room temperature].

Hypertension

Advise patients that treatment with recommended doses of XADAGO may be associated with elevations of blood pressure or onset of hypertension. Tell patients who experience elevation of blood pressure while taking XADAGO to contact their healthcare provider.

Explain the risk of using higher than recommended daily doses of XADAGO, and provide a brief description of the tyramine associated hypertensive reaction.

Advise patients to avoid certain foods (e.g., aged cheese) containing a very large amount of tyramine while taking recommended doses of XADAGO because of the potential for large increases in blood pressure. If patients eat foods very rich in tyramine and do not feel well soon after eating, they should contact their healthcare provider [see Warnings and Precautions (5.1)] .

Serotonin Syndrome

Tell patients to inform their physician if they are taking, or plan to take, any prescription or over-the-counter drugs, especially antidepressants and over-the-counter cold medications, because there is a potential for interaction with XADAGO. Because patients should not use meperidine or certain other analgesics with XADAGO, they should contact their healthcare provider before taking new medications including antidepressants, analgesics, and prescription or nonprescription decongestants [see Contraindications (4) and Warnings and Precautions (5.2)] .

Falling Asleep During Activities of Daily Living and Somnolence

Inform patients about the potential for sedating effects associated with XADAGO and other dopaminergic medications, including somnolence and particularly to the possibility of falling asleep while engaged in activities of daily living. Because somnolence can be a frequent adverse reaction with potentially serious consequences, patients should not operate a motor vehicle or engage in other potentially dangerous activities until they have gained sufficient experience with XADAGO.

Advise patients that if increased somnolence or new episodes of falling asleep during activities of daily living (e.g., watching television, passenger in a car, etc.) are experienced at any time during treatment, they should not drive or participate in potentially dangerous activities until they have contacted their physician. Patients should not drive, operate machinery, or work at heights during treatment if they have previously experienced somnolence and/or have fallen asleep without warning prior to use of XADAGO.

Because of possible additive effects, advise patients about the potential for increased somnolence when patients are taking other sedating medications, alcohol, or other central nervous system depressants (e.g., benzodiazepines, antipsychotics, antidepressants) in combination with XADAGO [see Warnings and Precautions (5.3)] .

Dyskinesia

Advise patients taking XADAGO as adjunct to levodopa that there is a possibility of dyskinesia or increased dyskinesia [see Warnings and Precautions (5.4)] .

Hallucinations / Psychotic Behavior

Inform patients that hallucinations or other manifestations of psychotic behavior can occur when taking XADAGO. Advise patients that, if they have a major psychotic disorder, that XADAGO should not ordinarily be used because of the risk of exacerbating the psychosis. Patients with a major psychotic disorder should also be aware that many treatments for psychosis may decrease the effectiveness of XADAGO [see Warnings and Precautions (5.5) and Drug Interactions (7.7)] .

Impulse Control/Compulsive Behaviors

Advise patients that they may experience intense urges to gamble, increased sexual urges, other intense urges, and the inability to control these urges while taking XADAGO. Although it is not proven that the medications caused these events, these urges were reported to have stopped in some cases when the dose was reduced or the medication was stopped. Prescribers should ask patients about the development of new or increased gambling urges, sexual urges, or other urges while being treated with XADAGO. Patients should inform their physician if they experience these urges while taking XADAGO [see Warnings and Precautions 5.6] .

Withdrawal-Emergent Hyperpyrexia and Confusion

Tell patients to contact their healthcare provider if they wish to discontinue XADAGO and seek guidance for tapering XADAGO instead of abruptly discontinuing XADAGO [see Warnings and Precautions (5.7)] .

Missing Dose

Instruct patients to take XADAGO as prescribed. If a dose is missed, instruct patients to take the next dose at the usual time on the following day.

Concomitant Medications

Advise patients to inform their physicians if they are taking, or plan to take, any prescription or over-the-counter medications because of a potential for interactions [see Contraindications (4), and Drug Interactions (7.3, 7.4, and 7.5)] .