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Pantoprazole Sodium Delayed-Release Tablets are indicated for: 1.1 Short-Term Treatment of Erosive Esophagitis Associated With Gastroesophageal Reflux Disease (GERD) Pantoprazole Sodium Delayed-Release Tablet is indicated in adults and pediatric patients five years of age and older for the short-term treatment (up to 8 weeks) in the healing and symptomatic relief of erosive esophagitis (EE). For those adult patients who have not healed after 8 weeks of treatment, an additional 8-week course of pantoprazole sodium delayed-release tablets may be considered. Safety of treatment beyond 8 weeks in pediatric patients has not been established. 1.2 Maintenance of Healing of Erosive Esophagitis Pantoprazole Sodium Delayed-Release Tablets are indicated for maintenance of healing of EE and reduction in relapse rates of daytime and nighttime heartburn symptoms in adult patients with GERD. Controlled studies did not extend beyond 12 months. 1.3 Pathological Hypersecretory Conditions Including Zollinger-Ellison Syndrome Pantoprazole Sodium Delayed-Release Tablets are indicated for the long-term treatment of pathological hypersecretory conditions, including Zollinger-Ellison (ZE) Syndrome.

Recommended Dosing Schedule Pantoprazole sodium is supplied as delayed-release tablets. The recommended dosages are outlined in Table 1. Table 1: Recommended Dosing Schedule for Pantoprazole Sodium Delayed-Release Tablets Indication Dose Frequency Short-Term Treatment of Erosive Esophagitis Associated With GERD Adults 40 mg Once daily for up to 8 weeks* Children (5 years and older) ≥ 15 kg to < 40 kg ≥ 40 kg 20 mg Once daily for up to 8 weeks 40 mg Maintenance of Healing of Erosive Esophagitis Adults 40 mg Once daily*** Pathological Hypersecretory Conditions Including Zollinger-Ellison Syndrome Adults 40 mg Twice daily ** * For adult patients who have not healed after 8 weeks of treatment, an additional 8-week course of pantoprazole sodium delayed-release tablets may be considered. ** Dosage regimens should be adjusted to individual patient needs and should continue for as long as clinically indicated. Doses up to 240 mg daily have been administered. *** Controlled studies did not extend beyond 12 months. 2.2 Administration Instructions Directions for method of administration for each dosage form are presented in Table 2. Table 2: Administration Instructions Formulation Route Instructions* Delayed-Release Tablets Oral Swallowed whole, with or without food * Do not split, chew, or crush Pantoprazole Sodium Delayed-Release Tablets. Take a missed dose as soon as possible. If it is almost time for the next dose, skip the missed dose and take the next dose at the regular scheduled time. Do not take 2 doses at the same time. Pantoprazole Sodium Delayed-Release Tablets Swallow Pantoprazole Sodium Delayed-Release Tablets whole, with or without food in the stomach. For patients unable to swallow a 40 mg tablet, two 20 mg tablets may be taken. Concomitant administration of antacids does not affect the absorption of Pantoprazole Sodium Delayed-Release Tablets.

Presence of Gastric Malignancy In adults, symptomatic response to therapy with pantoprazole sodium does not preclude the presence of gastric malignancy. Consider additional follow-up and diagnostic testing in adult patients who have a suboptimal response or an early symptomatic relapse after completing treatment with a PPI. In older patients, also consider an endoscopy. 5.2 Acute Tubulointerstitial Nephritis Acute tubulointerstitial nephritis (TIN) has been observed in patients taking PPIs and may occur at any point during PPI therapy. Patients may present with varying signs and symptoms from symptomatic hypersensitivity reactions to non-specific symptoms of decreased renal function (e.g., malaise, nausea, anorexia). In reported case series, some patients were diagnosed on biopsy and in the absence of extra-renal manifestations (e.g., fever, rash or arthralgia). Discontinue pantoprazole sodium delayed-release tablets and evaluate patients with suspected acute TIN [see Contraindications ( 4)]. 5.3 Clostridium difficile- Associated Diarrhea Published observational studies suggest that PPI therapy like pantoprazole sodium may be associated with an increased risk of Clostridium difficile associated diarrhea, especially in hospitalized patients. This diagnosis should be considered for diarrhea that does not improve [see Adverse Reactions ( 6.2)]. Patients should use the lowest dose and shortest duration of PPI therapy appropriate to the condition being treated. 5.4 Bone Fracture Several published observational studies suggest that PPI therapy may be associated with an increased risk for osteoporosis-related fractures of the hip, wrist, or spine. The risk of fracture was increased in patients who received high-dose, defined as multiple daily doses, and long-term PPI therapy (a year or longer). Patients should use the lowest dose and shortest duration of PPI therapy appropriate to the condition being treated. Patients at risk for osteoporosis-related fractures should be managed according to established treatment guidelines [see Dosage and Administration (2), Adverse Reactions (6.2)]. 5.5 Severe Cutaneous Adverse Reactions Severe cutaneous adverse reactions, including erythema multiforme, Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) have been reported in association with the use of PPIs [see Adverse Reactions ( 6.2)]. Discontinue pantoprazole sodium at the first signs or symptoms of severe cutaneous adverse reactions or other signs of hypersensitivity and consider further evaluation. 5.6 Cutaneous and Systemic Lupus Erythematosus Cutaneous lupus erythematosus (CLE) and systemic lupus erythematosus (SLE) have been reported in patients taking PPIs, including pantoprazole sodium. These events have occurred as both new onset and an exacerbation of existing autoimmune disease. The majority of PPI-induced lupus erythematous cases were CLE. The most common form of CLE reported in patients treated with PPIs was subacute CLE (SCLE) and occurred within weeks to years after continuous drug therapy in patients ranging from infants to the elderly. Generally, histological findings were observed without organ involvement. Systemic lupus erythematosus (SLE) is less commonly reported than CLE in patients receiving PPIs. PPI associated SLE is usually milder than non-drug induced SLE. Onset of SLE typically occurred within days to years after initiating treatment primarily in patients ranging from young adults to the elderly. The majority of patients presented with rash; however, arthralgia and cytopenia were also reported. Avoid administration of PPIs for longer than medically indicated. If signs or symptoms consistent with CLE or SLE are noted in patients receiving pantoprazole sodium, discontinue the drug and refer the patient to the appropriate specialist for evaluation. Most patients improve with discontinuation of the PPI alone in 4 to 12 weeks. Serological testing (e.g., ANA) may be positive and elevated serological test results may take longer to resolve than clinical manifestations. 5.7 Cyanocobalamin (Vitamin B-12) Deficiency Generally, daily treatment with any acid-suppressing medications over a long period of time (e.g., longer than 3 years) may lead to malabsorption of cyanocobalamin (Vitamin B-12) caused by hypo- or achlorhydria. Rare reports of cyanocobalamin deficiency occurring with acid-suppressing therapy have been reported in the literature. This diagnosis should be considered if clinical symptoms consistent with cyanocobalamin deficiency are observed. 5.8 Hypomagnesemia and Mineral Metabolism Hypomagnesemia, symptomatic and asymptomatic, has been reported rarely in patients treated with PPIs for at least three months, and in most cases after a year of therapy. Serious adverse events include tetany, arrhythmias, and seizures. Hypomagnesemia may lead to hypocalcemia and/or hypokalemia and may exacerbate underlying hypocalcemia in at-risk patients. In most patients, treatment of hypomagnesemia required magnesium replacement and discontinuation of the PPI. For patients expected to be on prolonged treatment or who take PPIs with medications such as digoxin or drugs that may cause hypomagnesemia (e.g., diuretics), health care professionals may consider monitoring magnesium levels prior to initiation of PPI treatment and periodically [see Adverse Reactions ( 6.2)]. Consider monitoring magnesium and calcium levels prior to initiation of pantoprazole sodium and periodically while on treatment in patients with a preexisting risk of hypocalcemia (e.g., hypoparathyroidism). Supplement with magnesium and/or calcium as necessary. If hypocalcemia is refractory to treatment, consider discontinuing the PPI. 5.9 Tumorigenicity Due to the chronic nature of GERD, there may be a potential for prolonged administration of pantoprazole sodium. In long-term rodent studies, pantoprazole was carcinogenic and caused rare types of gastrointestinal tumors. The relevance of these findings to tumor development in humans is unknown [see Nonclinical Toxicology ( 13.1)]. 5.10 Fundic Gland Polyps PPI use is associated with an increased risk of fundic gland polyps that increases with long-term use, especially beyond one year. Most PPI users who developed fundic gland polyps were asymptomatic and fundic gland polyps were identified incidentally on endoscopy. Use the shortest duration of PPI therapy appropriate to the condition being treated. 5.11 Interference with Investigations for Neuroendocrine Tumors Serum chromogranin A (CgA) levels increase secondary to drug-induced decreases in gastric acidity. The increased CgA level may cause false positive results in diagnostic investigations for neuroendocrine tumors. Healthcare providers should temporarily stop pantoprazole sodium treatment at least 14 days before assessing CgA levels and consider repeating the test if initial CgA levels are high. If serial tests are performed (e.g., for monitoring), the same commercial laboratory should be used for testing, as reference ranges between tests may vary [see Clinical Pharmacology ( 12.2)]. 5.12 Interference with Urine Screen for THC There have been reports of false-positive urine screening tests for tetrahydrocannabinol (THC) in patients receiving PPIs, including pantoprazole sodium [see Drug Interactions ( 7)]. 5.13 Concomitant Use of Pantoprazole Sodium with Methotrexate Literature suggests that concomitant use of PPIs with methotrexate (primarily at high dose; see methotrexate prescribing information) may elevate and prolong serum levels of methotrexate and/or its metabolite, possibly leading to methotrexate toxicities. In high-dose methotrexate administration, a temporary withdrawal of the PPI may be considered in some patients [see Drug Interactions ( 7)].

• Pantoprazole sodium delayed-release tablets are contraindicated in patients with known hypersensitivity to any component of the formulation or any substituted benzimidazole. Hypersensitivity reactions may include anaphylaxis, anaphylactic shock, angioedema, bronchospasm, acute tubulointerstitial nephritis, and urticaria [see Warnings and Precautions ( 5.2), Adverse Reactions ( 6)]. • Proton pump inhibitors (PPIs), including pantoprazole sodium delayed-release tablets, are contraindicated in patients receiving rilpivirine-containing products [see Drug Interactions ( 7)].

Table 4 includes drugs with clinically important drug interactions and interaction with diagnostics when administered concomitantly with pantoprazole sodium and instructions for preventing or managing them. Consult the labeling of concomitantly used drugs to obtain further information about interactions with PPIs. Table 4: Clinically Relevant Interactions Affecting Drugs Co-Administered with Pantoprazole Sodium and Interactions with Diagnostics Antiretrovirals Clinical Impact: The effect of PPIs on antiretroviral drugs is variable. The clinical importance and the mechanisms behind these interactions are not always known. • Decreased exposure of some antiretroviral drugs (e.g., rilpivirine atazanavir, and nelfinavir) when used concomitantly with pantoprazole may reduce antiviral effect and promote the development of drug resistance. • Increased exposure of other antiretroviral drugs (e.g., saquinavir) when used concomitantly with pantoprazole may increase toxicity of the antiretroviral drugs. • There are other antiretroviral drugs which do not result in clinically relevant interactions with pantoprazole. Intervention: Rilpivirine-containing products: Concomitant use with pantoprazole sodium is contraindicated [see Contraindications ( 4)] . See prescribing information. Atazanavir: See prescribing information for atazanavir for dosing information. Nelfinavir: Avoid concomitant use with pantoprazole sodium. See prescribing information for nelfinavir. Saquinavir: See the prescribing information for saquinavir and monitor for potential saquinavir toxicities. Other antiretrovirals: See prescribing information. Warfarin Clinical Impact: Increased INR and prothrombin time in patients receiving PPIs, including pantoprazole, and warfarin concomitantly. Increases in INR and prothrombin time may lead to abnormal bleeding and even death. Intervention: Monitor INR and prothrombin time. Dose adjustment of warfarin may be needed to maintain target INR range. See prescribing information for warfarin. Clopidogrel Clinical Impact: Concomitant administration of pantoprazole and clopidogrel in healthy subjects had no clinically important effect on exposure to the active metabolite of clopidogrel or clopidogrel-induced platelet inhibition [see Clinical Pharmacology ( 12.3)]. Intervention: No dose adjustment of clopidogrel is necessary when administered with an approved dose of pantoprazole sodium. Methotrexate Clinical Impact: Concomitant use of PPIs with methotrexate (primarily at high dose) may elevate and prolong serum concentrations of methotrexate and/or its metabolite hydroxymethotrexate, possibly leading to methotrexate toxicities. No formal drug interaction studies of high-dose methotrexate with PPIs have been conducted [see Warnings and Precautions ( 5.13)] . Intervention: A temporary withdrawal of pantoprazole sodium may be considered in some patients receiving high-dose methotrexate. Drugs Dependent on Gastric pH for Absorption (e.g., iron salts, erlotinib, dasatinib, nilotinib, mycophenolate mofetil, ketoconazole/itraconazole) Clinical Impact: Pantoprazole can reduce the absorption of other drugs due to its effect on reducing intragastric acidity. Intervention: Mycophenolate mofetil (MMF): Co-administration of pantoprazole sodium in healthy subjects and in transplant patients receiving MMF has been reported to reduce the exposure to the active metabolite, mycophenolic acid (MPA), possibly due to a decrease in MMF solubility at an increased gastric pH [see Clinical Pharmacology ( 12.3)] . The clinical relevance of reduced MPA exposure on organ rejection has not been established in transplant patients receiving pantoprazole sodium and MMF. Use pantoprazole sodium with caution in transplant patients receiving MMF. See the prescribing information for other drugs dependent on gastric pH for absorption. Interactions with Investigations of Neuroendocrine Tumors Clinical Impact: CgA levels increase secondary to PPI-induced decreases in gastric acidity. The increased CgA level may cause false positive results in diagnostic investigations for neuroendocrine tumors [see Warnings and Precautions (5.11), Clinical Pharmacology ( 12.2)] . Intervention: Temporarily stop pantoprazole sodium treatment at least 14 days before assessing CgA levels and consider repeating the test if initial CgA levels are high. If serial tests are performed (e.g., for monitoring), the same commercial laboratory should be used for testing, as reference ranges between tests may vary. False Positive Urine Tests for THC Clinical Impact: There have been reports of false positive urine screening tests for tetrahydrocannabinol (THC) in patients receiving PPIs [see Warnings and Precautions ( 5.12)] . Intervention: An alternative confirmatory method should be considered to verify positive results.

The following serious adverse reactions are described below and elsewhere in labeling: • Acute Tubulointerstitial Nephritis [see Warnings and Precautions (5.2)] • Clostridium difficile-Associated Diarrhea [see Warnings and Precautions (5.3)] • Bone Fracture [see Warnings and Precautions (5.4)] • Severe Cutaneous Adverse Reactions [see Warnings and Precautions ( 5.5)] • Cutaneous and Systemic Lupus Erythematosus [see Warnings and Precautions ( 5.6)] • Cyanocobalamin (Vitamin B-12) Deficiency [see Warnings and Precautions ( 5.7)] • Hypomagnesemia and Mineral Metabolism [see Warnings and Precautions ( 5.8)] • Fundic Gland Polyps [see Warnings and Precautions (5.10)] 6.1 Clinical Trials Experience The adverse reaction profiles for Pantoprazole Sodium For Delayed-Release Oral Suspension and Pantoprazole Sodium Delayed-Release Tablets are similar. 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. Adults Safety in nine randomized comparative US clinical trials in patients with GERD included 1,473 patients on oral pantoprazole sodium (20 mg or 40 mg), 299 patients on an H 2-receptor antagonist, 46 patients on another PPI, and 82 patients on placebo. The most frequently occurring adverse reactions are listed in Table 3. Table 3: Adverse Reactions Reported in Clinical Trials of Adult Patients with GERD at a Frequency of >2% Pantoprazole sodium (n=1473) % Comparators (n=345) % Placebo (n=82) % Headache 12.2 12.8 8.5 Diarrhea 8.8 9.6 4.9 Nausea 7.0 5.2 9.8 Abdominal pain 6.2 4.1 6.1 Vomiting Flatulence 4.3 3.9 3.5 2.9 2.4 3.7 Dizziness 3.0 2.9 1.2 Arthralgia 2.8 1.4 1.2 Additional adverse reactions that were reported for pantoprazole sodium in clinical trials with a frequency of ≤2% are listed below by body system: Body as a Whole: allergic reaction, pyrexia, photosensitivity reaction, facial edema Gastrointestinal: constipation, dry mouth, hepatitis Hematologic: leukopenia, thrombocytopenia Metabolic/Nutritional: elevated CK (creatine kinase), generalized edema, elevated triglycerides, liver enzymes elevated Musculoskeletal: myalgia Nervous: depression, vertigo Skin and Appendages: urticaria, rash, pruritus Special Senses: blurred vision Pediatric Patients Safety of pantoprazole sodium in the treatment of EE associated with GERD was evaluated in pediatric patients ages 1 year through 16 years in three clinical trials. Safety trials involved pediatric patients with EE; however, as EE is uncommon in the pediatric population, 249 pediatric patients with endoscopically-proven or symptomatic GERD were also evaluated. All adult adverse reactions to pantoprazole sodium are considered relevant to pediatric patients. In patients ages 1 year through 16 years, the most commonly reported (>4%) adverse reactions include: URI, headache, fever, diarrhea, vomiting, rash, and abdominal pain. For safety information in patients less than 1 year of age see Use in Specific Populations ( 8.4). Additional adverse reactions that were reported for pantoprazole sodium in pediatric patients in clinical trials with a frequency of ≤4% are listed below by body system: Body as a Whole: allergic reaction, facial edema Gastrointestinal: constipation, flatulence, nausea Metabolic/Nutritional: elevated triglycerides, elevated liver enzymes, elevated CK (creatine kinase) Musculoskeletal: arthralgia, myalgia Nervous: dizziness, vertigo Skin and Appendages: urticaria The following adverse reactions seen in adults in clinical trials were not reported in pediatric patients in clinical trials, but are considered relevant to pediatric patients: photosensitivity reaction, dry mouth, hepatitis, thrombocytopenia, generalized edema, depression, pruritus, leukopenia, and blurred vision. Zollinger-Ellison (ZE) Syndrome In clinical studies of ZE Syndrome, adverse reactions reported in 35 patients taking pantoprazole sodium 80 mg/day to 240 mg/day for up to 2 years were similar to those reported in adult patients with GERD. 6.2 Postmarketing Experience The following adverse reactions have been identified during postapproval use of pantoprazole sodium. 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. These adverse reactions are listed below by body system: Gastrointestinal Disorders: fundic gland polyps General Disorders and Administration Conditions: asthenia, fatigue, malaise Hematologic: pancytopenia, agranulocytosis Hepatobiliary Disorders: hepatocellular damage leading to jaundice and hepatic failure Immune System Disorders: anaphylaxis (including anaphylactic shock), systemic lupus erythematosus Infections and Infestations: Clostridium difficile associated diarrhea Investigations: weight changes Metabolism and Nutritional Disorders: hypomagnesemia, hypocalcemia, hypokalemia, hyponatremia Musculoskeletal Disorders: rhabdomyolysis, bone fracture Nervous: ageusia, dysgeusia Psychiatric Disorders: hallucination, confusion, insomnia, somnolence Renal and Urinary Disorders: acute tubulointerstitial nephritis Skin and Subcutaneous Tissue Disorders: severe dermatologic reactions (some fatal), including erythema multiforme, SJS/TEN, DRESS, AGEP, angioedema (Quincke’s edema) and cutaneous lupus erythematosus

Mechanism of Action Pantoprazole is a PPI that suppresses the final step in gastric acid production by covalently binding to the (H +, K +)-ATPase enzyme system at the secretory surface of the gastric parietal cell. This effect leads to inhibition of both basal and stimulated gastric acid secretion, irrespective of the stimulus. The binding to the (H +, K +)-ATPase results in a duration of antisecretory effect that persists longer than 24 hours for all doses tested (20 mg to 120 mg). 12.2 Pharmacodynamics Antisecretory Activity Under maximal acid stimulatory conditions using pentagastrin, a dose-dependent decrease in gastric acid output occurs after a single dose of oral (20 to 80 mg) or a single dose of intravenous (20 to 120 mg) pantoprazole in healthy subjects. Pantoprazole given once daily results in increasing inhibition of gastric acid secretion. Following the initial oral dose of 40 mg pantoprazole, a 51% mean inhibition was achieved by 2.5 hours. With once-a-day dosing for 7 days, the mean inhibition was increased to 85%. Pantoprazole suppressed acid secretion in excess of 95% in half of the subjects. Acid secretion had returned to normal within a week after the last dose of pantoprazole; there was no evidence of rebound hypersecretion. In a series of dose-response studies, pantoprazole, at oral doses ranging from 20 to 120 mg, caused dose-related increases in median basal gastric pH and in the percent of time gastric pH was >3 and >4. Treatment with 40 mg of pantoprazole produced significantly greater increases in gastric pH than the 20 mg dose. Doses higher than 40 mg (60, 80, 120 mg) did not result in further significant increases in median gastric pH. The effects of pantoprazole on median pH from one double-blind crossover study are shown in Table 5. Table 5: Effect of Single Daily Doses of Oral Pantoprazole on Intragastric pH ——————— Median pH on day 7——————— Time Placebo 20 mg 40 mg 80 mg 8 a.m. - 8 a.m. (24 hours) 1.3 2.9* 3.8*# 3.9*# 8 a.m. - 10 p.m. (Daytime) 1.6 3.2* 4.4*# 4.8*# 10 p.m. - 8 a.m. (Nighttime) 1.2 2.1* 3.0* 2.6* * Significantly different from placebo # Significantly different from 20 mg Serum Gastrin Effects Fasting serum gastrin levels were assessed in two double-blind studies of the acute healing of EE in which 682 patients with gastroesophageal reflux disease (GERD) received 10, 20, or 40 mg of pantoprazole sodium for up to 8 weeks. At 4 weeks of treatment there was an increase in mean gastrin levels of 7%, 35%, and 72% over pretreatment values in the 10, 20, and 40 mg treatment groups, respectively. A similar increase in serum gastrin levels was noted at the 8-week visit with mean increases of 3%, 26%, and 84% for the three pantoprazole dose groups. Median serum gastrin levels remained within normal limits during maintenance therapy with Pantoprazole Sodium Delayed-Release Tablets. In long-term international studies involving over 800 patients, a 2- to 3-fold mean increase from the pretreatment fasting serum gastrin level was observed in the initial months of treatment with pantoprazole at doses of 40 mg per day during GERD maintenance studies and 40 mg or higher per day in patients with refractory GERD. Fasting serum gastrin levels generally remained at approximately 2 to 3 times baseline for up to 4 years of periodic follow-up in clinical trials. Following short-term treatment with pantoprazole sodium, elevated gastrin levels return to normal by at least 3 months. Enterochromaffin-Like (ECL) Cell Effects In 39 patients treated with oral pantoprazole 40 mg to 240 mg daily (majority receiving 40 mg to 80 mg) for up to 5 years, there was a moderate increase in ECL-cell density, starting after the first year of use, which appeared to plateau after 4 years. In a nonclinical study in Sprague-Dawley rats, lifetime exposure (24 months) to pantoprazole at doses of 0.5 to 200 mg/kg/day resulted in dose-related increases in gastric ECL-cell proliferation and gastric neuroendocrine (NE)-cell tumors. Gastric NE-cell tumors in rats may result from chronic elevation of serum gastrin concentrations. The high density of ECL cells in the rat stomach makes this species highly susceptible to the proliferative effects of elevated gastrin concentrations produced by PPIs. However, there were no observed elevations in serum gastrin following the administration of pantoprazole at a dose of 0.5 mg/kg/day. In a separate study, a gastric NE-cell tumor without concomitant ECL-cell proliferative changes was observed in 1 female rat following 12 months of dosing with pantoprazole at 5 mg/kg/day and a 9 month off-dose recovery [see Nonclinical Toxicology ( 13.1)]. Endocrine Effects In a clinical pharmacology study, pantoprazole sodium 40 mg given once daily for 2 weeks had no effect on the levels of the following hormones: cortisol, testosterone, triiodothyronine (T 3), thyroxine (T 4), thyroid-stimulating hormone (TSH), thyronine-binding protein, parathyroid hormone, insulin, glucagon, renin, aldosterone, follicle-stimulating hormone, luteinizing hormone, prolactin, and growth hormone. In a 1-year study of GERD patients treated with pantoprazole sodium 40 mg or 20 mg, there were no changes from baseline in overall levels of T 3, T 4, and TSH. 12.3 Pharmacokinetics Pantoprazole Sodium Delayed-Release Tablets are prepared as enteric-coated tablets so that absorption of pantoprazole begins only after the tablet leaves the stomach. Peak serum concentration (C max) and area under the serum concentration time curve (AUC) increase in a manner proportional to oral and intravenous doses from 10 mg to 80 mg. Pantoprazole does not accumulate, and its pharmacokinetics are unaltered with multiple daily dosing. Following oral or intravenous administration, the serum concentration of pantoprazole declines biexponentially, with a terminal elimination half-life of approximately one hour. In extensive metabolizers with normal liver function receiving an oral dose of the enteric-coated 40 mg pantoprazole tablet, the peak concentration (C max) is 2.5 mcg/mL; the time to reach the peak concentration (t max) is 2.5 h, and the mean total area under the plasma concentration versus time curve (AUC) is 4.8 mcg•h/mL (range 1.4 to 13.3 mcg•h/mL). Following intravenous administration of pantoprazole to extensive metabolizers, its total clearance is 7.6 to 14.0 L/h, and its apparent volume of distribution is 11.0 to 23.6 L. Absorption After administration of a single or multiple oral 40 mg doses of Pantoprazole Sodium Delayed-Release Tablets, the peak plasma concentration of pantoprazole was achieved in approximately 2.5 hours, and C max was 2.5 mcg/mL. Pantoprazole undergoes little first-pass metabolism, resulting in an absolute bioavailability of approximately 77%. Pantoprazole absorption is not affected by concomitant administration of antacids. Administration of Pantoprazole Sodium Delayed-Release Tablets with food may delay its absorption up to 2 hours or longer; however, the C max and the extent of pantoprazole absorption (AUC) are not altered. Thus, Pantoprazole Sodium Delayed-Release Tablets may be taken without regard to timing of meals. Distribution The apparent volume of distribution of pantoprazole is approximately 11 to 23.6 L, distributing mainly in extracellular fluid. The serum protein binding of pantoprazole is about 98%, primarily to albumin. Elimination Metabolism Pantoprazole is extensively metabolized in the liver through the cytochrome P450 (CYP) system. Pantoprazole metabolism is independent of the route of administration (intravenous or oral). The main metabolic pathway is demethylation, by CYP2C19, with subsequent sulfation; other metabolic pathways include oxidation by CYP3A4. There is no evidence that any of the pantoprazole metabolites have significant pharmacologic activity. Excretion After a single oral or intravenous dose of 14C-labeled pantoprazole to healthy, normal metabolizer subjects, approximately 71% of the dose was excreted in the u