Lofexidine

1 INDICATIONS AND USAGE Lofexidine tablets are indicated for mitigation of opioid withdrawal symptoms to facilitate abrupt opioid discontinuation in adults. Lofexidine tablets are a central alpha-2 adrenergic agonist indicated for mitigation of opioid withdrawal symptoms to facilitate abrupt opioid discontinuation in adults.

2 DOSAGE AND ADMINISTRATION • The usual lofexidine tablets dosage are three 0.18 mg tablets taken orally 4 times daily at 5-to 6-hour intervals lofexidine tablets treatment may be continued for up to14 days with dosing guided by symptoms. ( 2.1 ) • Discontinue lofexidine tablets with a gradual dose reduction over 2 to 4 days.( 2.1 ) • Hepatic or Renal Impairment: Dosage adjustments are recommended based on degree of impairment. ( 2.2 , 2.3 ) 2.1 Dosing Information The usual lofexidine tablets starting dosage is three 0.18 mg tablets taken orally 4 times daily during the period of peak withdrawal symptoms (generally the first 5 to 7 days following last use of opioid) with dosing guided by symptoms and side effects. There should be 5 to 6 hours between each dose. The total daily dosage of lofexidine tablets should not exceed 2.88 mg (16 tablets) and no single dose should exceed 0.72 mg (4 tablets). Lofexidine tablets treatment may be continued for up to 14 days with dosing guided by symptoms. Discontinue lofexidine tablets with a gradual dose reduction over a 2- to 4-day period to mitigate lofexidine tablets withdrawal symptoms (e.g., reducing by 1 tablet per dose every 1 to 2 days). [see Warnings & Precautions (5.5) ]. The lofexidine tablets dose should be reduced, held, or discontinued for individuals who demonstrate a greater sensitivity to lofexidine tablets side effects [see Adverse Reactions (6.1), Warnings and Precautions (5.1) ]. Lower doses may be appropriate as opioid withdrawal symptoms wane. Lofexidine tablets can be administered in the presence or absence of food. 2.2 Dosage Recommendations for Patients with Hepatic Impairment Recommended dosage adjustments based on the degree of hepatic impairment are shown in Table 1. [see Use in Specific Populations (8.5), Clinical Pharmacology (12.3) ]. Table 1: Dosage Recommendations in Patients with Hepatic Impairment Mild Impairment Moderate Impairment Severe Impairment Child-Pugh score 5-6 7-9 > 9 Recommended dose 3 tablets 4 times daily (2.16 mg per day) 2 tablets 4 times daily (1.44 mg per day) 1 tablet 4 times daily (0.72 mg per day) 2.3 Dosage Recommendations for Patients with Renal Impairment Recommended dosage adjustments based on the degree of renal impairment are shown in Table 2. Lofexidine tablets may be administered without regard to the timing of dialysis [see Use in Specific Populations (8.6), Clinical Pharmacology (12.3) ]. Table 2: Dosage Recommendations in Patients with Renal Impairment Mild or Moderate Impairment Severe Impairment, End-Stage Renal Disease, or on Dialysis Estimated GFR, mL/min/1.73 m 2 30-89.9 < 30 Recommended dose 2 tablets 4 times daily (1.44 mg per day) 1 tablet 4 times daily (0.72 mg per day)

3 DOSAGE FORMS AND STRENGTHS Lofexidine tablets are available as round, concave-shaped, peach-colored, film-coated tablets, debossed with “C” on one side and “71” on other side. Each tablet contains 0.18 mg lofexidine (equivalent to 0.2 mg of lofexidine hydrochloride). Tablets: 0.18 mg.

4 CONTRAINDICATIONS None. None.

6 ADVERSE REACTIONS The following serious adverse reactions are described elsewhere in labeling: • Hypotension, Bradycardia, and Syncope [see Warnings and Precautions ( 5.1 )] • QT Prolongation [see Warnings and Precautions ( 5.2 )] • Central Nervous System Depression [see Warnings and Precautions ( 5.3 )] • Opioid Overdose [see Warnings and Precautions ( 5.4 )] • Discontinuation Symptoms [see Warnings and Precautions ( 5.5 )] Most common adverse reactions (incidence ≥ 10% and notably more frequent than placebo) are orthostatic hypotension, bradycardia, hypotension, dizziness, somnolence, sedation, and dry mouth. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Indoco Remedies Limited at 1-833-856-0880 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch 6.1 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 adverse reaction rates observed for another drug and may not reflect the rates observed in practice. The safety of Lofexidine tablets was supported by three randomized, double-blind, placebo-controlled clinical trials, an open-label study, and clinical pharmacology studies with concomitant administration of either methadone, buprenorphine, or naltrexone. The three randomized, double-blind, placebo-controlled clinical trials enrolled 935 subjects dependent on short-acting opioids undergoing abrupt opioid withdrawal. Patients were monitored before each dose in an inpatient setting. Table 3 presents the incidence, rounded to the nearest percent, of adverse events that occurred in at least 10% of subjects treated with Lofexidine tablets and for which the incidence in patients treated with Lofexidine tablets were greater than the incidence in subjects treated with placebo in a study that tested two doses of Lofexidine tablets, 2.16 mg per day and 2.88 mg per day, and placebo. The overall safety profile in the combined dataset was similar. Orthostatic hypotension, bradycardia, hypotension, dizziness, somnolence, sedation, and dry mouth were notably more common in subjects treated with lofexidine tablet than subjects treated with placebo. Table 3: Adverse Reactions Reported by ≥10% of Lofexidine Tablet-Treated Patients and More Frequently than Placebo Adverse Reaction Lofexidine Tablets 2.16 mg 1 (%)N=229 Lofexidine Tablets 2.88 mg 1 (%) N=222 Placebo (%) N=151 Insomnia 51 55 48 Orthostatic Hypotension 29 42 5 Bradycardia 24 32 5 Hypotension 30 30 1 Dizziness 19 23 3 Somnolence 11 13 5 Sedation 13 12 5 Dry Mouth 10 11 0 1 Assigned dose; mean average daily dose received was 79% of assigned dose due to dose-holds for out-of-range vital signs. Other notable adverse reactions associated with the use of Lofexidine tablets but reported in <10% of patients in the Lofexidine tablets group included: Syncope: 0.9%, 1.4% and 0% for Lofexidine tablets 2.16 mg/day and 2.88 mg/day and placebo, respectively Tinnitus: 0.9%, 3.2% and 0% for Lofexidine tablets 2.16 mg/day and 2.88 mg/day and placebo, respectively Blood pressure changes and adverse reactions after Lofexidine tablets cessation Elevations in blood pressure above normal values (≥ 140 mmHg systolic) and above a subject’s pre-treatment baseline are associated with discontinuing Lofexidine tablets, and peaked on the second day after discontinuation, as shown in Table 4. Blood pressure values were evaluated for 3 days following the last dose of a 5-day course of Lofexidine tablets 2.88mg/day. Table 4: Blood Pressure Elevations after Stopping Treatment Abrupt Lofexidine Tablets Discontinuation 2.88 mg (N = 134) Placebo (N = 129) N at risk n (%) N at risk n (%) Systolic Blood Pressure on Day 2 after Discontinuation ≥ 140 mmHg and ≥ 20 mmHg increase from baseline ≥ 170 mmHg and ≥ 20 mmHg increase from baseline 58 23(39.7) 58 5(8.6) 37 6 (16.2) 37 0 Blood pressure elevations of a similar magnitude and incidence were observed in a small number of pati …

7 DRUG INTERACTIONS Methadone : Methadone and Lofexidine tablets both prolong the QT interval. ECG monitoring is recommended when used concomitantly. ( 7.1 ) Oral Naltrexone : Concomitant use may reduce efficacy of oral naltrexone. ( 7.2 ) CYP2D6 Inhibitors : Concomitant use of paroxetine resulted in increased plasma levels of Lofexidine. Monitor for symptoms of orthostasis and bradycardia with concomitant use of a CYP2D6 inhibitor. ( 7.4 ) 7.1 Methadone Lofexidine tablets and methadone both prolong the QT interval. ECG monitoring is recommended in patients receiving methadone and Lofexidine tablets concomitantly [see Warnings and Precautions ( 5.2 ), Clinical Pharmacology ( 12.3 )]. 7.2 Oral Naltrexone Coadministration of Lofexidine tablets and oral naltrexone resulted in statistically significant differences in the steady-state pharmacokinetics of naltrexone. It is possible that oral naltrexone efficacy may be reduced if used concomitantly within 2 hours of Lofexidine tablets. This interaction is not expected if naltrexone is administered by non-oral routes [see Clinical Pharmacology ( 12.3 )] . 7.3 CNS Depressant Drugs Lofexidine tablets potentiate the CNS depressant effects of benzodiazepines and may potentiate the CNS depressant effects of alcohol, barbiturates, and other sedating drugs. Advise patients to inform their healthcare provider of other medications they are taking, including alcohol [see Warnings and Precautions ( 5.3 )]. 7.4 CYP2D6 Inhibitor - Paroxetine Coadministration of Lofexidine tablets and paroxetine resulted in a 28% increase in the extent of absorption of Lofexidine. Monitor for orthostatic hypotension and bradycardia when an inhibitor of CYP2D6 is used concomitantly with Lofexidine tablets [see Clinical Pharmacology ( 12.3 )].

8 USE IN SPECIFIC POPULATIONS 8.1 Pregnancy Risk Summary The safety of Lofexidine tablets in pregnant women has not been established. In animal reproduction studies, oral administration of lofexidine during organogenesis to pregnant rats and rabbits caused a reduction in fetal weights, increases in fetal resorptions, and litter loss at exposures below that in humans. When oral lofexidine was administered from the beginning of organogenesis through lactation, increased stillbirths and litter loss were noted along with decreased viability and lactation indices. The offspring exhibited delays in sexual maturation, auditory startle, and surface righting. These effects occurred at exposures below that in humans [see Animal Data]. The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies carry some risk of birth defect, loss, or other adverse outcomes. The background risk of major birth defects in the U.S. general population is 2% to 4% and of miscarriage is 15% to 20% of clinically recognized pregnancies. Data Animal Data Increased incidence of resorptions, decreased number of implantations, and a concomitant reduction in the number of fetuses were observed when pregnant rabbits were orally administered lofexidine hydrochloride during organogenesis (from gestation day [GD] 7 to 19) at a daily dose of 5.0 mg/kg/day (approximately 0.08 times the maximum recommended human dose [MRHD] of 2.88 mg lofexidine base on an AUC basis). Maternal toxicity evidenced by increased mortality was noted at the highest tested dose of 15 mg/kg/day (approximately 0.4 times the MRHD on an AUC basis). Decreased implantations per dam and decreased mean fetal weights were noted in a study in which pregnant rats were treated with oral lofexidine hydrochloride during organogenesis (from GD 7 to 16) at a daily dose of 3.0 mg/kg/day (approximately 0.9 times the MRHD on an AUC basis). This dose was associated with maternal toxicity (decreased body weight gain and mortality). No malformations or evidence of developmental toxicity were evident at 1.0 mg/kg/day (approximately 0.2 times the MRHD on an AUC basis). A dose-dependent increase in pup mortality was noted in all doses of lofexidine hydrochloride administered orally to pregnant rats from GD 6 through lactation at an exposure less than the human exposure based on AUC comparisons. Doses higher than 1.0 mg/kg/day (approximately 0.2 times the MRHD on an AUC basis) resulted in incidences of total litter loss and maternal toxicity (piloerection and decreased body weight gain). At the highest dose tested of 2.0 mg/kg/day (approximately 0.6 times the MRHD on an AUC basis), increased stillbirths as well as decreased viability and lactation indices were reported. Surviving offspring exhibited lower body weights, developmental delays, and increased delays in auditory startle at doses of 1.0 mg/kg/day or higher. Sexual maturation was delayed in male offspring (preputial separation) at 2.0 mg/kg/day and in female offspring (vaginal opening) at 1.0 mg/kg/day or higher. 8.2 Lactation Risk Summary There is no information regarding the presence of lofexidine or its metabolites in human milk, the effects on the breastfed infant, or the effects on milk production. Caution should be exercised when lofexidine tablets are administered to a nursing woman. The developmental and health benefits should be considered along with the mother’s clinical need for Lofexidine tablets and any other potential adverse effects on breast-fed children from Lofexidine tablets or from the underlying maternal condition. 8.3 Females and Males of Reproductive Potential In animal studies that included some fertility endpoints, lofexidine decreased breeding rate and increased resorptions at exposures below human exposures. The impact of lofexidine on male fertility has not been adequately characterized in animal studies [see Impairment of Fertility ( 13.1 )]. 8.4 Pediatric Use The safety and effe …

12.1 Mechanism of Action Lofexidine is a central alpha-2 adrenergic agonist that binds to receptors on adrenergic neurons. This reduces the release of norepinephrine and decreases sympathetic tone.

11 DESCRIPTION Lofexidine tablets contain lofexidine, a central alpha-2 adrenergic agonist, as the hydrochloride salt. Lofexidine hydrochloride is chemically designated as 2-[1-(2,6-dichlorophenoxy)ethyl]-4,5 dihydro-1 H - imidazole monohydrochloride with a molecular formula of C 11 H 12 Cl 2 N 2 O•HCl. Its molecular weight is 295.6 g/mole and its structural formula is: Lofexidine hydrochloride is a white to off-white crystalline powder freely soluble in water, methanol, and ethanol. It is slightly soluble in chloroform and practically insoluble in n-hexane and benzene. Lofexidine tablets are available as round, concave-shaped, peach-colored, film-coated tablets, debossed with “C” on one side and “71” on other side for oral administration. Each tablet contains 0.18 lofexidine, equivalent to 0.2 mg of lofexidine hydrochloride and the following inactive ingredients: 87 mg lactose monohydrate, 12.3 mg citric acid monohydrate, 5.7 mg microcrystalline cellulose, 1.1 mg povidone K-30, 0.70 mg sodium lauryl sulphate, 5.0 mg sodium starch glycolate, 2.0 mg calcium stearate and Opadry AMB II orange 88A530003 (contains polyvinyl alcohol, talc, titanium dioxide, Glyceryl mono and dicaprylocaprate, sodium lauryl sulfate, FD&C yellow #6/sunset yellow FCF aluminum lake and FD&C blue #2/indigo carmine aluminium lake). lofexidine-structure

10 OVERDOSAGE Overdose with Lofexidine tablets may manifest as hypotension, bradycardia, and sedation. In the event of acute overdose, perform gastric lavage where appropriate. Dialysis will not remove a substantial portion of the drug. Initiate general symptomatic and supportive measures in cases of overdosage.

16 HOW SUPPLIED/STORAGE AND HANDLING How Supplied Available as 0.18 mg round, concave-shaped, peach colored, film-coated tablets, debossed with “C” on one side and “71” on other side; approximately 7 mm in diameter. Bottle of 36 tablets........................NDC 71921-250-36 Bottle of 96 tablets........................NDC 71921-250-96 Storage Store in original container at controlled room temperature, 25°C (77°F); with excursions permitted between 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Keep Lofexidine tablets away from excess heat and moisture both in the pharmacy and after dispensing. Do not remove desiccant packs from bottles until all tablets are used. Keep Lofexidine tablets and all medicines out of the reach of children.