selegiline hydrochloride 15 MG Oral Tablet

INDICATIONS AND USAGE Selegiline Hydrochloride Tablets USP are indicated as an adjunct in the management of Parkinsonian patients being treated with levodopa/carbidopa who exhibit deterioration in the quality of their response to this therapy. There is no evidence from controlled studies that selegiline has any beneficial effect in the absence of concurrent levodopa therapy. Evidence supporting this claim was obtained in randomized controlled clinical investigations that compared the effects of added selegiline or placebo in patients receiving levodopa/carbidopa. Selegiline was significantly superior to placebo on all three principal outcome measures employed: change from baseline in daily levodopa/carbidopa dose, the amount of 'off' time, and patient self-rating of treatment success. Beneficial effects were also observed on other measures of treatment success (e.g., measures of reduced end of dose akinesia, decreased tremor and sialorrhea, improved speech and dressing ability and improved overall disability as assessed by walking and comparison to previous state).

DOSAGE AND ADMINISTRATION • Initiate treatment with 1.25 mg given once a day for at least 6 weeks; after 6 weeks, the dose may be escalated to 2.5 mg once a day (2.1 ) • Place tablet on top of the tongue where the tablet will disintegrate in seconds; avoid food and liquid intake 5 minutes before and after each dose (2.1 ) • In patients with mild or moderate hepatic impairment, the dose should be reduced to 1.25 mg; ZELAPAR is not recommended in patients with severe (Child-Pugh score >9) hepatic impairment ( 2.2 ) 2.1 General Dosage Recommendations Initiate treatment with 1.25 mg given once a day for at least 6 weeks. After 6 weeks, the dose may be increased to 2.5 mg given once a day if a desired benefit has not been achieved and the patient is tolerating ZELAPAR. There is no evidence that doses greater than 2.5 mg a day provide additional benefit, and they should ordinarily be avoided because of the potential increased risk of adverse events. Take ZELAPAR in the morning before breakfast and without liquid. Patients should avoid ingesting food or liquids for 5 minutes before and after taking ZELAPAR. Patients should not attempt to push ZELAPAR through the foil backing. Patients should PEEL BACK the backing of one or two blisters (as prescribed) with dry hands, and GENTLY remove the tablet(s). Patients should IMMEDIATELY place the ZELAPAR tablet(s) on top of the tongue where it will disintegrate in seconds. 2.2 Patients with Hepatic Impairment In patients with mild to moderate hepatic disease (Child-Pugh score 5 to 9), the daily dose of ZELAPAR should be reduced (from 2.5 to 1.25 mg daily), depending on the clinical response. ZELAPAR is not recommended in patients with severe hepatic impairment (Child-Pugh score greater than 9) [see Use in Specific Populations (8.6) and Clinical Pharmacology (12.3) ]. 2.3 Patients with Renal Impairment No dose adjustment of ZELAPAR is required in patients with mild to moderate renal impairment (creatinine clearance [CLcr] 30 to 89 mL/min). The maintenance dose of ZELAPAR (1.25 mg or 2.5 mg) is determined by the individual clinical response. ZELAPAR is not recommended in patients with severe renal impairment and patients with end-stage renal disease [ESRD] (creatinine clearance [CLcr] <30 mL/min) [see Use in Specific Populations (8.7) and Clinical Pharmacology (12.3) ].

WARNINGS AND PRECAUTIONS • May cause hypertension above 2.5 mg/day (5.1) • May cause serotonin syndrome when used with antidepressants (5.2) • May cause falling asleep during activities of daily living (5.3) • May cause hypotension/orthostatic hypotension (5.4) • May cause or exacerbate dyskinesia (5.5) • May cause hallucinations and psychotic-like behavior (5.6) • May cause problems with impulse control and compulsive behaviors (5.7) • Abrupt discontinuation may cause hyperpyrexia and confusion (5.8) • May cause irritation of the buccal mucosa ( 5.9 ) • Increased risk for patients with phenylketonuria ( 5.10 ) 5.1 Hypertension ZELAPAR should not be used at daily doses exceeding those recommended (2.5 mg/day) because of the risks associated with non-selective inhibition of MAO [see Drug Interactions (7.3) and Clinical Pharmacology (12.2) ]. The selectivity of ZELAPAR for MAO-B may not be absolute even at the recommended daily dose of 2.5 mg daily. The selectivity of MAO-B inhibitors typically decreases, and it is ultimately lost as the dose is increased beyond recommended doses. Hypertensive reactions associated with ingestion of tyramine-containing foods have been reported even in patients taking the recommended daily dose of swallowed selegiline, a dose which is generally believed to be selective for MAO-B. Selectivity for MAO-B inhibition is gradually lost with increasing daily doses. An increase in tyramine sensitivity for blood pressure responses appears to begin at a dose of 5 mg ZELAPAR daily [see Drug Interactions (7.5) ] . However, the precise dose at which ZELAPAR becomes a non-selective inhibitor of all MAO enzymes in individual patients is unknown. Reports of hypertensive reactions have occurred in patients who ingested tyramine-containing consumables (i.e., food or drink) while receiving swallowed selegiline at the recommended dose (a dose believed to be relatively selective for MAO-B). The safe use of ZELAPAR at doses above 2.5 mg daily without dietary tyramine restrictions has not been established. A pharmacodynamic study showed increased tyramine sensitivity for increasing blood pressure and decreased selectivity for MAO-B with dosing above the recommended level (2.5 mg daily) [see Clinical Pharmacology (12.2) ]. Uncontrolled hypertension has been reported when taking the recommended dose of swallowed selegiline and a sympathomimetic medication (ephedrine). After starting ZELAPAR, monitor patients for new onset hypertension or exacerbation of hypertension that is not adequately controlled. 5.2 Serotonin Syndrome Serotonin syndrome and hyperpyrexia have been reported with the combined treatment of an antidepressant (e.g., selective serotonin reuptake inhibitors-SSRIs, serotonin-norepinephrine reuptake inhibitors-SNRIs, tricyclic antidepressants, tetracyclic antidepressants, triazolopyridine antidepressants) and a non-selective MAOI (e.g., phenelzine, tranylcypromine) or selective MAO-B inhibitors, such as selegiline (ELDEPRYL), rasagiline (AZILECT), and olanzapine (Zydis) selegiline (ZELAPAR). Serotonin syndrome is a potentially serious condition, which can result in death. Typical clinical signs and symptoms include behavioral and cognitive/mental status changes (e.g., confusion, hypomania, hallucinations, agitation, delirium, headache, and coma), autonomic effects (e.g., syncope, shivering, sweating, high fever/hyperthermia, hypertension, hypotension, tachycardia, nausea, diarrhea), and somatic effects (e.g., muscular rigidity, myoclonus, muscle twitching, hyperreflexia manifested by clonus, and tremor). In the post-marketing period, fatal and non-fatal cases of serotonin syndrome have been reported in patients treated with antidepressants concomitantly with ZELAPAR [see Contraindications (4) and Drug Interactions ( 7.1 , 7.2 , 7.3 ) ]. Clinical studies of ZELAPAR did not allow concomitant use of any selective serotonin re-uptake inhibitor (e.g., fluoxetine-Prozac, fluvoxamine-Luvox, paroxetine-Paxil, sertraline, venlafaxine-Effexor, or nefazodone-Serzone) or any non-selective serotonin reuptake inhibiting antidepressant drug (except when taken at a low dose and only at night for the purpose of effective sleep) with ZELAPAR. Because the mechanisms responsible for these reactions are not fully understood, avoid the combination of ZELAPAR with any antidepressant. At least 14 days should elapse between discontinuation of ZELAPAR and initiation of treatment with a SSRI, SNRI, tricyclic, tetracyclic, or triazolopyridine antidepressant. In patients taking antidepressants with a long half-life (e.g., fluoxetine and its active metabolite), allow at least five weeks (perhaps longer, especially if fluoxetine has been prescribed chronically and/or at higher doses) to elapse between discontinuation of fluoxetine and initiation of ZELAPAR [see Drug Interactions (7.6) ]. 5.3 Falling Asleep During Activities of Daily Living and Somnolence Patients with Parkinson’s disease treated with ZELAPAR or other drugs increasing dopaminergic tone 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, some did not perceive warning signs, such as excessive drowsiness, and believed that they were alert immediately prior to the event. Some of these events have been reported as late as one year after initiation of treatment. It has been reported that falling asleep while engaged in activities of daily living always 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. Somnolence may occur in patients receiving ZELAPAR. There was an increased risk for somnolence in geriatric patients (≥65 years) vs. non-geriatric patients treated with ZELAPAR. Prescribers should also be aware that patients may not acknowledge drowsiness or sleepiness until directly questioned about drowsiness or sleepiness during specific activities. Patients should be advised to exercise caution while driving, operating machines, or working at heights during treatment with ZELAPAR. Patients who have already experienced somnolence and/or an episode of sudden sleep onset should not participate in these activities during treatment with ZELAPAR. Before initiating treatment with ZELAPAR, advise patients about the potential to develop drowsiness and specifically ask about factors that may increase this risk, such as concomitant sedating medications and the presence of sleep disorders. If a patient develops daytime sleepiness or episodes of falling asleep during activities that require active participation (e.g., conversations, eating, etc.), ZELAPAR should ordinarily be discontinued. If a decision is made to continue ZELAPAR, patients should be advised not to drive and to avoid other potentially dangerous activities. There is insufficient information to establish whether dose reduction will eliminate episodes of falling asleep while engaged in activities of daily living. 5.4 Hypotension/Orthostatic Hypotension Assessments of orthostatic (supine and standing) blood pressures at different times throughout the 12 week study period in two controlled trials showed that the frequency of orthostatic hypotension (>20 mm Hg decrease in systolic blood pressure and/or >10 mm Hg decrease in diastolic blood pressure) was greater with ZELAPAR treatment than with placebo treatment. Patients taking ZELAPAR were most likely to experience a decline in systolic and diastolic blood pressure at 8 weeks (2 weeks after initiating 2.5 mg ZELAPAR). At that time, the incidence of systolic orthostatic hypotension was about 21% in ZELAPAR-treated patients and 9% in placebo-treated patients. The incidence of diastolic orthostatic hypotension was about 12% in ZELAPAR-treated patient

CONTRAINDICATIONS ZELAPAR is contraindicated in patients with: • Concomitant use of opioid drugs (e.g., meperidine, tramadol, or methadone). Serotonin syndrome, a potentially serious condition, which can result in death, has been reported with concomitant use of meperidine (e.g., Demerol and other trade names). At least 14 days should elapse between discontinuation of ZELAPAR and initiation of treatment with these medications [see Warnings and Precautions (5.2) ] . • Concomitant use of other drugs in the monoamine oxidase inhibitor (MAOI) class or other drugs that are potent inhibitors of monoamine oxidase, including linezolid), because of an increased risk for hypertensive crisis [see Warnings and Precautions (5.1)]. At least 14 days should elapse between discontinuation of ZELAPAR and initiation of treatment with any MAO inhibitor. • Concomitant use of St. John’s wort or cyclobenzaprine (a tricyclic muscle relaxant). • Concomitant use of dextromethorphan, because of reported episodes of psychosis or bizarre behavior. ZELAPAR is contraindicated in patients using the following drugs: opioid drugs (e.g., meperidine, tramadol, methadone), MAO inhibitors including selective MAO-B inhibitors, dextromethorphan, St. John’s wort, and cyclobenzaprine ( 4 )

CLINICAL PHARMACOLOGY The mechanisms accounting for selegiline's beneficial adjunctive action in the treatment of Parkinson's disease are not fully understood. Inhibition of monoamine oxidase, type B, activity is generally considered to be of primary importance; in addition, there is evidence that selegiline may act through other mechanisms to increase dopaminergic activity. Selegiline is best known as an irreversible inhibitor of monoamine oxidase (MAO), an intracellular enzyme associated with the outer membrane of mitochondria. Selegiline inhibits MAO by acting as a 'suicide' substrate for the enzyme; that is, it is converted by MAO to an active moiety which combines irreversibly with the active site and/or the enzyme's essential FAD cofactor. Because selegiline has greater affinity for type B rather than for type A active sites, it can serve as a selective inhibitor of MAO type B if it is administered at the recommended dose. MAOs are widely distributed throughout the body; their concentration is especially high in liver, kidney, stomach, intestinal wall, and brain. MAOs are currently subclassified into two types, A and B, which differ in their substrate specificity and tissue distribution. In humans, intestinal MAO is predominantly type A, while most of that in brain is type B. In CNS neurons, MAO plays an important role in the catabolism of catecholamines (dopamine, norepinephrine and epinephrine) and serotonin. MAOs are also important in the catabolism of various exogenous amines found in a variety of foods and drugs. MAO in the GI tract and liver (primarily type A), for example, is thought to provide vital protection from exogenous amines (e.g., tyramine) that have the capacity, if absorbed intact, to cause a 'hypertensive crisis,' the so-called 'cheese reaction.' (If large amounts of certain exogenous amines gain access to the systemic circulation - e.g., from fermented cheese, red wine, herring, over-the-counter cough/cold medications, etc. - they are taken up by adrenergic neurons and displace norepinephrine from storage sites within membrane bound vesicles. Subsequent release of the displaced norepinephrine causes the rise in systemic blood pressure, etc.) In theory, since MAO A of the gut is not inhibited, patients treated with selegiline at a dose of 10 mg a day should be able to take medications containing pharmacologically active amines and consume tyramine-containing foods without risk of uncontrolled hypertension. Although rare, a few reports of hypertensive reactions have occurred in patients receiving selegiline at the recommended dose, with tyramine-containing foods. In addition, one case of hypertensive crisis has been reported in a patient taking the recommended dose of selegiline and a sympathomimetic medication, ephedrine. The pathophysiology of the 'cheese reaction' is complicated and, in addition to its ability to inhibit MAO B selectively, selegiline's relative freedom from this reaction has been attributed to an ability to prevent tyramine and other indirect acting sympathomimetics from displacing norepinephrine from adrenergic neurons. However, until the pathophysiology of the 'cheese reaction' is more completely understood, it seems prudent to assume that selegiline can ordinarily only be used safely without dietary restrictions at doses where it presumably selectively inhibits MAO B (e.g., 10 mg/day). In short, attention to the dose dependent nature of selegiline's selectivity is critical if it is to be used without elaborate restrictions being placed on diet and concomitant drug use although, as noted above, a few cases of hypertensive reactions have been reported at the recommended dose. (See WARNINGS and PRECAUTIONS.) It is important to be aware that selegiline may have pharmacological effects unrelated to MAO B inhibition. As noted above, there is some evidence that it may increase dopaminergic activity by other mechanisms, including interfering with dopamine re-uptake at the synapse. Effects resulting from selegiline administration may also be mediated through its metabolites. Two of its three principal metabolites, amphetamine and methamphetamine, have pharmacological actions of their own; they interfere with neuronal uptake and enhance release of several neurotransmitters (e.g., norepinephrine, dopamine, serotonin). However, the extent to which these metabolites contribute to the effects of selegiline are unknown. Rationale for the Use of a Selective Monoamine Oxidase Type B Inhibitor in Parkinson's Disease Many of the prominent symptoms of Parkinson's disease are due to a deficiency of striatal dopamine that is the consequence of a progressive degeneration and loss of a population of dopaminergic neurons which originate in the substantia nigra of the midbrain and project to the basal ganglia or striatum. Early in the course of Parkinson's Disease, the deficit in the capacity of these neurons to synthesize dopamine can be overcome by administration of exogenous levodopa, usually given in combination with a peripheral decarboxylase inhibitor (carbidopa). With the passage of time, due to the progression of the disease and/or the effect of sustained treatment, the efficacy and quality of the therapeutic response to levodopa diminishes. Thus, after several years of levodopa treatment, the response, for a given dose of levodopa, is shorter, has less predictable onset and offset (i.e., there is 'wearing off'), and is often accompanied by side effects (e.g., dyskinesia, akinesias, on-off phenomena, freezing, etc.). This deteriorating response is currently interpreted as a manifestation of the inability of the ever decreasing population of intact nigrostriatal neurons to synthesize and release adequate amounts of dopamine. MAO B inhibition may be useful in this setting because, by blocking the catabolism of dopamine, it would increase the net amount of dopamine available (i.e., it would increase the pool of dopamine). Whether or not this mechanism or an alternative one actually accounts for the observed beneficial effects of adjunctive selegiline is unknown. Selegiline's benefit in Parkinson's disease has only been documented as an adjunct to levodopa/carbidopa. Whether or not it might be effective as a sole treatment is unknown, but past attempts to treat Parkinson's disease with nonselective MAOI monotherapy are reported to have been unsuccessful. It is important to note that attempts to treat Parkinsonian patients with combinations of levodopa and currently marketed non-selective MAO inhibitors were abandoned because of multiple side effects including hypertension, increase in involuntary movement and toxic delirium. Pharmacokinetic Information (Absorption, Distribution, Metabolism and Elimination - ADME) The absolute bioavailability of selegiline following oral dosing is not known; however, selegiline undergoes extensive metabolism (presumably attributable to presystemic clearance in gut and liver). The major plasma metabolites are N-desmethylselegiline, L-amphetamine and L-methamphetamine. Only N-desmethylselegiline has MAO-B inhibiting activity. The peak plasma levels of these metabolites following a single oral dose of 10 mg are from 4 to almost 20 times greater than that of the maximum plasma concentration of selegiline (1 ng/mL). The maximum concentrations of amphetamine and methamphetamine, however, are far below those ordinarily expected to produce clinically important effects. Single oral dose studies do not predict multiple dose kinetics, however, at steady state the peak plasma level of selegiline is 4 fold that obtained following a single dose. Metabolite concentrations increase to a lesser extent, averaging 2 fold that seen after a single dose. The bioavailability of selegiline is increased 3 to 4 fold when it is taken with food. The extent of systemic exposure to selegiline at a given dose varies considerably among individuals. Estimates of systemic clearance of selegiline are not available. Following