Ztlido

1 INDICATIONS AND USAGE ZTLIDO is indicated for relief of pain associated with post-herpetic neuralgia (PHN) in adults. ZTLIDO contains lidocaine, an amide local anesthetic, and is indicated for relief of pain associated with post-herpetic neuralgia (PHN) in adults ( 1 ).

2 DOSAGE AND ADMINISTRATION Because of the difference in bioavailability of ZTLIDO compared to Lidoderm®, a different dosage strength is required to be administered to the patient. One ZTLIDO (lidocaine topical system) 1.8% provides equivalent lidocaine exposure to one Lidoderm (lidocaine patch 5%). ( 2.1 ) Apply ZTLIDO to intact skin to cover the most painful area. Apply the prescribed number of topical systems (maximum of 3) only once for up to 12 hours in a 24-hour period. ( 2.2 ) ZTLIDO may be cut into smaller sizes prior to removal of the release liner. ( 2.2 ) In patients who are debilitated or have impaired elimination, smaller areas of treatment are recommended. Achieve this by cutting ZTLIDO with scissors into a smaller size prior to removing the release liner. ( 2.2 ) 2.1 Important Dosage and Administration Instructions Because of the difference in bioavailability of ZTLIDO compared to Lidoderm (lidocaine patch 5%), a different dosage strength is required to be administered to the patient. One ZTLIDO (lidocaine topical system) 1.8% provides equivalent lidocaine exposure to one Lidoderm (lidocaine patch 5%) [see Clinical Pharmacology (12.3) ]. When ZTLIDO is used concomitantly with other products containing local anesthetic agents, the total amount of drug absorbed from all formulations must be considered. Clearly instruct and advise patients: to wash hands immediately after handling ZTLIDO and to avoid contact with eyes [see Warnings and Precautions (5.6) ] . to store ZTLIDO inside the sealed envelope out of the reach of children, pets, and others and to apply immediately after removal from the envelope. to fold used ZTLIDO so that the adhesive side sticks to itself and to safely discard used ZTLIDO or pieces of cut ZTLIDO where children and pets cannot get to them [see Warnings and Precautions (5.1) ] . to never apply external heat sources, such as heating pads or electric blankets, directly to ZTLIDO, because plasma lidocaine levels are increased. ZTLIDO can be applied, however, to the administration site after moderate heat exposure, such as 15 minutes of heating pad exposure on a medium setting [see Warnings and Precautions (5.2) , Clinical Pharmacology (12.3) ] . that clothing may be worn over the area of application. that ZTLIDO may be used during moderate exercise, such as biking for 30 minutes. that ZTLIDO may be exposed to water, such as showering for 10 minutes or immersion for 15 minutes. to dry the topical system, after water exposure, by gently patting the skin, not by rubbing the skin or topical system. that ZTLIDO topical systems that have lifted at the edges may be reattached by pressing firmly on the edges and that fully detached topical systems may be reapplied as originally directed. that if a ZTLIDO topical system comes off completely and will not stick to patient's skin, to remove and properly dispose of the used ZTLIDO and to apply a new ZTLIDO topical system for a total duration of 12 hours of used and new topical system together. that if irritation or a burning sensation occurs during application, to remove ZTLIDO and to not reapply until the irritation subsides [see Warnings and Precautions (5.4) ] . 2.2 Treatment of Post-Herpetic Neuralgia Advise patients to apply ZTLIDO to intact skin to cover the most painful area and to apply the prescribed number of topical systems (maximum of 3), only once for up to 12 hours within a 24-hour period (12 hours on and 12 hours off) [see Warnings and Precautions (5.2) ] . In patients who are debilitated or have impaired elimination, smaller areas of treatment are recommended. Achieve this by cutting ZTLIDO with scissors into a smaller size prior to removing the release liner.

4 CONTRAINDICATIONS ZTLIDO is contraindicated in patients with a known history of sensitivity to local anesthetics of the amide type, or to any other component of the product. ZTLIDO is contraindicated in patients with a known history of sensitivity to local anesthetics of the amide type, or to any other component of the product. ( 4 )

5 WARNINGS AND PRECAUTIONS Accidental Exposure : Even a used ZTLIDO topical system contains residual lidocaine after use. It is important for patients to store and dispose of ZTLIDO properly and keep out of the reach of children, pets, and others. ( 5.1 ) Excessive Dosing/Overexposure : Applying ZTLIDO to larger surface areas or for a longer duration than recommended could lead to increased absorption and high blood concentrations of lidocaine, leading to adverse effects. ( 5.2 ) Increased Absorption on Non-Intact Skin : May result in higher blood concentrations of lidocaine. ( 5.2 ) Risk of Overexposure with External Heat Sources : Applying external heat sources to ZTLIDO may result in increased drug exposure. ( 5.2 ) Methemoglobinemia : Cases of methemoglobinemia have been reported in association with local anesthetic use. ( 5.3 ) Application Site Reactions : During or immediately after treatment with ZTLIDO, application site reactions may develop. ( 5.4 ) Hypersensitivity Reactions : Cross sensitivity to ZTLIDO in patients with a history of drug sensitivity to para-aminobenzoic acid (PABA) derivatives is possible. ( 5.5 ) Eye Exposure : Immediately wash out the eye with water or saline and protect the eye until sensation returns. ( 5.6 ). 5.1 Accidental Exposure A used ZTLIDO topical system contains residual lidocaine after use. The potential exists for a small child or a pet to suffer serious adverse effects from chewing or ingesting a new or used ZTLIDO. It is important for patients to store and dispose of ZTLIDO properly, and keep out of the reach of children, pets, and others [see Dosage and Administration (2.1) ]. 5.2 Excessive Dosing/Overexposure to Lidocaine Lidocaine toxicity can be expected at lidocaine blood concentrations above 5 mcg/mL. The blood concentration of lidocaine is determined by the rate and extent of lidocaine absorption and elimination. Longer duration of application, application of more than the recommended number of ZTLIDO, smaller patients, or impaired elimination may all contribute to increasing the blood concentration of lidocaine. If lidocaine overdose is suspected, check drug blood concentration. Management of overdose includes close monitoring, supportive care, and symptomatic treatment [see Overdosage (10) ] . Improper Application and Duration of Use : Application of more than the recommended number of ZTLIDO or applying ZTLIDO for longer than the recommended wearing time (12 hours of every 24 hours) could result in increased absorption and high blood concentrations of lidocaine, leading to adverse reactions. Advise patients on proper application and duration. Hepatic Disease : Impaired elimination may contribute to increasing blood concentrations of lidocaine. Patients with severe hepatic disease are at greater risk of developing toxic blood concentrations of lidocaine because of their inability to metabolize lidocaine normally. Use on Non-Intact Skin : Application to broken or inflamed skin, although not tested, may result in higher blood concentrations of lidocaine from increased absorption. ZTLIDO is only recommended for use on intact skin. Advise patients not to apply ZTLIDO to non-intact skin. External Heat Sources : External heat sources may increase drug exposure, leading to overexposure to lidocaine. Advise patients not to apply external heat sources to ZTLIDO during administration [see Clinical Pharmacology (12.3) ]. 5.3 Methemoglobinemia Cases of methemoglobinemia have been reported in association with local anesthetic use. Although all patients are at risk for methemoglobinemia, patients with glucose-6-phosphate dehydrogenase deficiency, congenital or idiopathic methemoglobinemia, cardiac or pulmonary compromise, infants under 6 months of age, and concurrent exposure to oxidizing agents or their metabolites are more susceptible to developing clinical manifestations of the condition. If local anesthetics must be used in these patients, close monitoring for symptoms and signs of methemoglobinemia is recommended. Signs of methemoglobinemia may occur immediately or may be delayed some hours after exposure, and are characterized by a cyanotic skin discoloration and/or abnormal coloration of the blood. Methemoglobin levels may continue to rise; therefore, immediate treatment is required to avert more serious central nervous system and cardiovascular adverse effects, including seizures, coma, arrhythmias, and death. Discontinue ZTLIDO and any other oxidizing agents. Depending on the severity of the signs and symptoms, patients may respond to supportive care, i.e., oxygen therapy, hydration. A more severe clinical presentation may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. 5.4 Application Site Reactions During or immediately after treatment with ZTLIDO, the skin at the site of application may develop blisters, bruising, burning sensation, depigmentation, dermatitis, discoloration, edema, erythema, exfoliation, irritation, papules, petechia, pruritus, vesicles, or may be the locus of abnormal sensation. These reactions are generally mild and transient, resolving spontaneously within a few minutes to hours. If application site reactions occur while the topical system is being worn, advise the patient to remove ZTLIDO and not to reapply until skin reactions subside. 5.5 Hypersensitivity Reactions Patients allergic to para-aminobenzoic acid (PABA) derivatives (procaine, tetracaine, benzocaine, etc.) have not shown cross-sensitivity to lidocaine. However, be aware of the potential for cross-sensitivity in patients allergic to PABA derivatives, especially if the etiologic agent is uncertain. Manage hypersensitivity reactions by conventional means. The detection of sensitivity by skin testing is of doubtful value. 5.6 Eye Exposure The contact of ZTLIDO with eyes, although not studied, should be avoided based on findings of severe eye irritation with the application of similar products in animals. If eye contact occurs, immediately wash out the eye with water or saline and protect the eye (such as, eye glasses/eye wear) until sensation returns.

7 DRUG INTERACTIONS Class I Antiarrhythmic Drugs: When ZTLIDO is used in patients receiving Class I antiarrhythmic drugs (such as tocainide and mexiletine) the toxic effects are additive and potentially synergistic. Consider risk/benefit before concomitant use. ( 7.2 ) Local Anesthetic Agents: When ZTLIDO is used concomitantly with other products containing local anesthetic agents, the effects are additive. Consider the amount of drug absorbed from all formulations when local anesthetics are administered concomitantly. ( 7.3 ) 7.1 Drugs That May Cause Methemoglobinemia When Used with ZTLIDO Patients who are administered local anesthetics may be at increased risk of developing methemoglobinemia when concurrently exposed to the following drugs, which could include other local anesthetics: Examples of Drugs Associated with Methemoglobinemia: Class Examples Nitrates/Nitrites nitric oxide, nitroglycerin, nitroprusside, nitrous oxide Local anesthetics articaine, benzocaine, bupivacaine, lidocaine, mepivacaine, prilocaine, procaine, ropivacaine, tetracaine Antineoplastic agents cyclophosphamide, flutamide, hydroxyurea, ifosfamide, rasburicase Antibiotics dapsone, nitrofurantoin, para-aminosalicyclic acid, sulfonamides Antimalarials chloroquine, primaquine Anticonvulsants phenobarbital, phenytoin, sodium valproate Other drugs acetaminophen, metoclopramide, quinine, sulfasalazine 7.2 Antiarrhythmic Drugs When ZTLIDO is used in patients receiving Class I antiarrhythmic drugs (such as tocainide and mexiletine), the toxic effects are additive and potentially synergistic. Consider risk/benefit during concomitant use. 7.3 Local Anesthetics When ZTLIDO is used concomitantly with other products containing local anesthetic agents, the effects are additive. Consider the amount of drug absorbed from all formulations when local anesthetic agents are administered concomitantly.

6 ADVERSE REACTIONS The following serious adverse reactions are described elsewhere in the labeling: Excessive Dosing/Overexposure to Lidocaine [see Warnings and Precautions (5.2) ] Methemoglobinemia [see Warnings and Precautions (5.3) ] Application Site Reactions [see Warnings and Precautions (5.4) ] Hypersensitivity Reactions [see Warnings and Precautions (5.5) ] Eye Irritation [see Warnings and Precautions (5.6) ] The following adverse reactions from voluntary reports or clinical studies have been reported with lidocaine. Because some of these reactions were 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. Skin and subcutaneous tissues : blisters, bruising, burning sensation, depigmentation, dermatitis, discoloration, edema, erosions, erythema, exfoliation, flushing, irritation, papules, petechia, pruritus, vesicles, and abnormal sensation. Immune system : angioedema, bronchospasm, dermatitis, dyspnea, hypersensitivity, laryngospasm, pruritus, shock, and urticaria. Central Nervous System : lightheadedness, nervousness, apprehension, euphoria, confusion, dizziness, drowsiness, tinnitus, blurred or double vision, sensations of heat, cold or numbness, twitching, tremors, convulsions, unconsciousness, somnolence, respiratory depression and arrest. Cardiovascular : bradycardia, hypotension, and cardiovascular collapse leading to arrest. Other : asthenia, disorientation, headache, hyperesthesia, hypoesthesia, metallic taste, nausea, pain exacerbated, paresthesia, taste alteration, and vomiting. Common adverse reactions are application site reactions such as irritation, erythema, and pruritus. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Scilex Pharmaceuticals Inc. at 1-866-SCILEX3 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

8.1 Pregnancy Risk Summary The limited human data with lidocaine in pregnant woman are not sufficient to inform drug-associated risk for major birth defects and miscarriage. The use of lidocaine for labor neuraxial analgesia has not been associated with an increased incidence of adverse fetal effects either during delivery or during the neonatal period (see Data ) . Should ZTLIDO be used concomitantly with other products containing lidocaine, consider total drug doses contributed by all formulations. In a published animal reproduction study, pregnant rats administered lidocaine by continuous subcutaneous infusion at a dose approximately 45 times the maximum recommended daily dose (MRDD) of 108 mg in ZTLIDO during the period of organogenesis resulted in lower fetal body weights. In a published animal reproduction study, pregnant rats administered lidocaine, containing 1:100,000 epinephrine, injected into the masseter muscle of the jaw or into the gum of the lower jaw at 0.5 times the MRDD on Gestation Day 11 resulted in developmental delays in neonates (see Data ) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies carry some risk of birth defects, loss, or other adverse outcomes. 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 Human Data In 22 parturient women given 1.5% lidocaine epidural anesthesia, there were no effects on neonatal behavior, using the early neonatal neurobehavioral scale (ENNS). Neuraxial analgesia also did not affect fetal heart rate, beat-to-beat variability, or uterine activity. Animal Data Reproductive studies with lidocaine have been performed in rats at doses up to 30 mg/kg (2.7 times the maximum recommended daily dose [MRDD] of 108 mg from ZTLIDO on a mg/m 2 basis) subcutaneously and have revealed no evidence of harm to the fetus due to lidocaine. In a published study, lidocaine administered to pregnant rats by continuous subcutaneous infusion during the period of organogenesis at 100, 250, and 500 mg/kg/day, did not produce any structural abnormalities, but did result in lower fetal weights at 500 mg/kg/day dose (approximately 45 times the MRDD on a mg/m 2 basis) in the absence of maternal toxicity. In a published study, lidocaine containing 1:100,000 epinephrine at a dose of 6 mg/kg (approximately 0.5 times the MRDD on a mg/m 2 basis) injected into the masseter muscle of the jaw or into the gum of the lower jaw of pregnant Long-Evans hooded rats on Gestation Day 11 resulted in developmental delays in the neonates. Developmental delays were observed for negative geotaxis, static righting reflex, visual discrimination response, sensitivity and response to thermal and electrical shock stimuli, and water maze acquisition. The developmental delays of the neonatal animals were transient, with responses becoming comparable to untreated animals later in life. The clinical relevance of these animal data is uncertain.