1.1 Healing of Erosive or Ulcerative GERD in Adults

Rabeprazole sodium delayed-release tablets are indicated for short-term (4 to 8 weeks) treatment in the healing and symptomatic relief of erosive or ulcerative gastroesophageal reflux disease (GERD). For those patients who have not healed after 8 weeks of treatment, an additional 8-week course of rabeprazole sodium delayed-release tablets may be considered.

1.2 Maintenance of Healing of Erosive or Ulcerative GERD in Adults

Rabeprazole sodium delayed-release tablets are indicated for maintaining healing and reduction in relapse rates of heartburn symptoms in patients with erosive or ulcerative gastroesophageal reflux disease (GERD Maintenance). Controlled studies do not extend beyond 12 months.

1.3 Treatment of Symptomatic GERD in Adults

Rabeprazole sodium delayed-release tablets are indicated for the treatment of daytime and nighttime heartburn and other symptoms associated with GERD in adults for up to 4 weeks.

1.4 Healing of Duodenal Ulcers in Adults

Rabeprazole sodium delayed-release tablets are indicated for short-term (up to four weeks) treatment in the healing and symptomatic relief of duodenal ulcers. Most patients heal within four weeks.

1.5 Helicobacter pylori Eradication to Reduce the Risk of Duodenal Ulcer Recurrence in Adults

Rabeprazole sodium delayed-release tablets, in combination with amoxicillin and clarithromycin as a three drug regimen, are indicated for the treatment of patients with H. pylori infection and duodenal ulcer disease (active or history within the past 5 years) to eradicate H. pylori. Eradication of H. pylori has been shown to reduce the risk of duodenal ulcer recurrence.

In patients who fail therapy, susceptibility testing should be done. If resistance to clarithromycin is demonstrated or susceptibility testing is not possible, alternative antimicrobial therapy should be instituted [see Clinical Pharmacology (12.2) and the full prescribing information for clarithromycin]. 

1.6 Treatment of Pathological Hypersecretory Conditions, Including Zollinger-Ellison Syndrome in Adults

Rabeprazole sodium delayed-release tablets are indicated for the long-term treatment of pathological hypersecretory conditions, including Zollinger-Ellison syndrome.

1.7 Treatment of Symptomatic GERD in Adolescent Patients 12 Years of Age and Older

Rabeprazole sodium delayed-release tablets are indicated for the treatment of symptomatic GERD in adolescents 12 years of age and above for up to 8 weeks.

Table 1 shows the recommended dosage of rabeprazole delayed-release tablets in adults and adolescent patients 12 years of age and older. The use of rabeprazole delayed-release tablets is not recommended for use in pediatric patients 1 year to less than 12 years of age because the lowest available tablet strength (20 mg) exceeds the recommended dose for these patients. Use another rabeprazole formulation for pediatric patients 1 year to less than 12 years of age.

Administration Instructions

• Swallow rabeprazole sodium delayed-release tablets whole. Do not chew, crush, or split tablets.
• For the treatment of duodenal ulcers take rabeprazole delayed-release tablets after a meal.
• For Helicobacter pylori eradication take rabeprazole delayed-release tablets with food.
• For all other indications rabeprazole sodium delayed-release tablets can be taken with or without food.
• Take a missed dose as soon as possible. If it is almost time for the next dose, skip the missed dose and go back to the normal schedule. Do not take two doses at the same time.

Rabeprazole sodium delayed-release tablets are provided in one strength, 20 mg. The tablets are yellow, round, biconvex, coated tablets, imprinted with "L020" (black ink) on one side.

• Rabeprazole sodium delayed-release tablets are contraindicated in patients with known hypersensitivity to rabeprazole, substituted benzimidazoles, or to any component of the formulation. Hypersensitivity reactions may include anaphylaxis, anaphylactic shock, angioedema, bronchospasm, acute tubulointerstitial nephritis, and urticaria [see Warnings and Precautions (5.3), Adverse Reactions (6)] .
• PPIs, including rabeprazole sodium delayed-release tablets, are contraindicated with rilpivirine-containing products [see Drug Interactions (7)].
• For information about contraindications of antibacterial agents (clarithromycin and amoxicillin) indicated in combination with rabeprazole sodium delayed-release tablets, refer to the [Contraindications ] section of their package inserts.

5.1 Presence of Gastric Malignancy

In adults, symptomatic response to therapy with rabeprazole 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.

5.2 Interaction with Warfarin

Steady state interactions of rabeprazole and warfarin have not been adequately evaluated in patients. There have been reports of increased INR and prothrombin time in patients receiving a proton pump inhibitor and warfarin concomitantly. Increases in INR and prothrombin time may lead to abnormal bleeding and even death. Patients treated with rabeprazole sodium delayed-release tablets and warfarin concomitantly may need to be monitored for increases in INR and prothrombin time [see Drug Interactions (7)].

5.3 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 rabeprazole sodium and evaluate patients with suspected acute TIN [see Contraindication(4)].

5.4 Clostridium difficile-Associated Diarrhea

Published observational studies suggest that PPI therapy like rabeprazole 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.

Clostridium difficile-associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents. For more information specific to antibacterial agents (clarithromycin and amoxicillin) indicated for use in combination with rabeprazole sodium, refer to Warnings and Precautions sections of the corresponding prescribing information.

5.5 Bone Fracture

Several published observational studies in adults 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)].

5.6 Severe Cutaneous Adverse Reactions

Severe cutaneous adverse reactions, including Stevens-Johnson syndrome (SJS) and 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 rabeprazole sodium delayed-release tablets at first signs or symptoms of severe cutaneous adverse reactions or other signs of hypersensitivity and consider further evaluation.

5.7 Cutaneous and Systemic Lupus Erythematosus

Cutaneous lupus erythematosus (CLE) and systemic lupus erythematosus (SLE) have been reported in patients taking PPIs, including rabeprazole. These events have occurred as both new onset and an exacerbation of existing autoimmune disease. The majority of PPI-induced lupus erythematosus 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 rabeprazole sodium delayed-release tablets, 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.

5.8 Cyanocobalamin (Vitamin B-12) Deficiency

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 in patients treated with rabeprazole sodium delayed-release tablets.

5.9 Hypomagnesemia and Mineral Metabolism

Hypomagnesemia, symptomatic and asymptomatic, has been reported rarely in patients treated with PPIs for at least three months, 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 rabeprazole sodium delayed-release tablets 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.

5.10 Interaction with Methotrexate

Literature suggests that concomitant use of PPIs with methotrexate (primarily at high dose; see methotrexate prescribing information) may elevate and prolong serum concentrations 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)].

5.11 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.

The following serious adverse reactions are described below and elsewhere in labeling:

• Acute Tubulointerstitial Nephritis [see Warnings and Precautions (5.3)]
• Clostridium difficile-Associated Diarrhea [see Warnings and Precautions (5.4)]
• Bone Fracture [see Warnings and Precautions (5.5)]
• Cutaneous and Systemic Lupus Erythematosus [see Warnings and Precautions(5.7)]
• Cyanocobalamin (Vitamin B-12) Deficiency [see Warnings and Precautions(5.8)]
• Hypomagnesemia and Mineral Metabolism[see Warnings and Precautions (5.9)]
• Fundic Gland Polyps [see Warnings and Precautions(5.11)]

6.1 Clinical Studies Experience

Because clinical trials are conducted under 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 practice.

Adults

The data described below reflect exposure to rabeprazole sodium delayed-release tablets in 1064 adult patients exposed for up to 8 weeks. The studies were primarily placebo- and active-controlled trials in adult patients with Erosive or Ulcerative Gastroesophageal Reflux Disease (GERD), Duodenal Ulcers and Gastric Ulcers. The population had a mean age of 53 years (range 18 to 89 years) and had a ratio of approximately 60% male: 40% female. The racial distribution was 86% Caucasian, 8% African American, 2% Asian, and 5% other. Most patients received either 10 mg, 20 mg or 40 mg per day of rabeprazole sodium delayed-release tablets.

An analysis of adverse reactions appearing in ≥2% of patients treated with rabeprazole sodium delayed-release tablets (n=1064) and with a greater frequency than placebo (n=89) in controlled North American and European acute treatment trials, revealed the following adverse reactions: pain (3% vs. 1%), pharyngitis (3% vs. 2%), flatulence (3% vs. 1%), infection (2% vs. 1%), and constipation (2% vs. 1%).

Three long-term maintenance studies consisted of a total of 740 adult patients; at least 54% of adult patients were exposed to rabeprazole sodium delayed-release tablets for 6 months and at least 33% were exposed for 12 months. Of the 740 adult patients, 247 (33%) and 241 (33%) patients received 10 mg and 20 mg of rabeprazole sodium delayed-release tablets, respectively, while 169 (23%) patients received placebo and 83 (11%) received omeprazole.

The safety profile of rabeprazole in the maintenance studies in adults was consistent with what was observed in the acute studies.

Less common adverse reactions seen in controlled clinical trials (<2% of patients treated with rabeprazole sodium delayed-release tablets and greater than placebo) and for which there is a possibility of a causal relationship to rabeprazole, include the following: headache, abdominal pain, diarrhea, dry mouth, dizziness, peripheral edema, hepatic enzyme increase, hepatitis, hepatic encephalopathy, myalgia, and arthralgia.

Combination Treatment with Amoxicillin and Clarithromycin:

In clinical trials using combination therapy with rabeprazole plus amoxicillin and clarithromycin (RAC), no adverse reactions unique to this drug combination were observed. In the U.S. multicenter study, the most frequently reported drug related adverse reactions for patients who received RAC therapy for 7 or 10 days were diarrhea (8% and 7%) and taste perversion (6% and 10%), respectively.

No clinically significant laboratory abnormalities particular to the drug combinations were observed.

For more information on adverse reactions or laboratory changes with amoxicillin or clarithromycin, refer to their respective prescribing information, Adverse Reactions section.

Pediatrics

In a multicenter, open-label study of adolescent patients 12 to 16 years of age with a clinical diagnosis of symptomatic GERD or endoscopically proven GERD, the adverse event profile was similar to that of adults. The adverse reactions reported without regard to relationship to rabeprazole sodium delayed-release tablets that occurred in ≥2% of 111 patients were headache (9.9%), diarrhea (4.5%), nausea (4.5%), vomiting (3.6%), and abdominal pain (3.6%). The related reported adverse reactions that occurred in ≥2% of patients were headache (5.4%) and nausea (1.8%). There were no adverse reactions reported in this study that were not previously observed in adults.

6.2 Postmarketing Experience

The following adverse reactions have been identified during post approval use of rabeprazole. 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:

Blood and Lymphatic System Disorders: agranulocytosis, hemolytic anemia, leukopenia, pancytopenia, thrombocytopenia

Ear and Labyrinth Disorders: vertigo

Eye Disorders: blurred vision

Gastrointestinal Disorders: fundic gland polyps

General Disorders and Administration Site Conditions: sudden death

Hepatobiliary Disorders: jaundice

Immune System Disorders: anaphylaxis, angioedema, systemic lupus erythematosus, Stevens-Johnson syndrome, toxic epidermal necrolysis (some fatal), DRESS, AGEP

Infections and Infestations: Clostridium difficile-associated diarrhea

Investigations: Increases in prothrombin time/INR (in patients treated with concomitant warfarin), TSH elevations

Metabolism and Nutrition Disorders: hyperammonemia, hypomagnesemia, hypocalcemia, hypokalemia [Warnings and Precautions(5.9)], hyponatremia

Musculoskeletal System Disorders: bone fracture, rhabdomyolysis

Nervous System Disorders: coma

Psychiatric Disorders: delirium, disorientation

Renal and Genitourinary Disorders: interstitial nephritis, erectile dysfunction

Respiratory, Thoracic and Mediastinal Disorders: interstitial pneumonia

Skin and Subcutaneous Tissue Disorders: severe dermatologic reactions including bullous and other drug eruptions of the skin, cutaneous lupus erythematosus, erythema multiforme

Table 2 includes drugs with clinically important drug interactions and interaction with diagnostics when administered concomitantly with rabeprazole sodium delayed-release tablets and instructions for preventing or managing them.

Consult the labeling of concomitantly used drugs to obtain further information about interactions with PPIs.

8.1 Pregnancy

Risk Summary

There are no available human data on rabeprazole sodium delayed-release tablets use in pregnant women to inform the drug associated risk. The background risk of major birth defects and miscarriage for the indicated populations are unknown. However, the background risk in the U.S. general population of major birth defects is 2 to 4% and of miscarriage is 15 to 20% of clinically recognized pregnancies. No evidence of adverse developmental effects were seen in animal reproduction studies with rabeprazole administered during organogenesis at 13 and 8 times the human area under the plasma concentration-time curve (AUC) at the recommended dose for GERD, in rats and rabbits, respectively [see Data].

Changes in bone morphology were observed in offspring of rats treated with oral doses of a different PPI through most of pregnancy and lactation. When maternal administration was confined to gestation only, there were no effects on bone physeal morphology in the offspring at any age [see Data].

Data

Animal Data:

Embryo-fetal developmental studies have been performed in rats during organogenesis at intravenous doses of rabeprazole up to 50 mg/kg/day (plasma AUC of 11.8 mcg•hr/mL, about 13 times the human exposure at the recommended oral dose for GERD) and rabbits at intravenous doses up to 30 mg/kg/day (plasma AUC of 7.3 mcg•hr/mL, about 8 times the human exposure at the recommended oral dose for GERD) and have revealed no evidence of harm to the fetus due to rabeprazole.

Administration of rabeprazole to rats in late gestation and during lactation at an oral dose of 400 mg/kg/day (about 195-times the human oral dose based on mg/m2) resulted in decreases in body weight gain of the pups.

A pre- and postnatal developmental toxicity study in rats with additional endpoints to evaluate bone development was performed with a different PPI at about 3.4 to 57 times an oral human dose on a body surface area basis. Decreased femur length, width and thickness of cortical bone, decreased thickness of the tibial growth plate, and minimal to mild bone marrow hypocellularity were noted at doses of this PPI equal to or greater than 3.4 times an oral human dose on a body surface area basis. Physeal dysplasia in the femur was also observed in offspring after in utero and lactational exposure to the PPI at doses equal to or greater than 33.6 times an oral human dose on a body surface area basis. Effects on maternal bone were observed in pregnant and lactating rats in a pre- and postnatal toxicity study when the PPI was administered at oral doses of 3.4 to 57 times an oral human dose on a body surface area basis. When rats were dosed from gestational day 7 through weaning on postnatal day 21, a statistically significant decrease in maternal femur weight of up to 14% (as compared to placebo treatment) was observed at doses equal to or greater than 33.6 times an oral human dose on a body surface area basis.

A follow-up developmental toxicity study in rats with further time points to evaluate pup bone development from postnatal day 2 to adulthood was performed with a different PPI at oral doses of 280 mg/kg/day (about 68 times an oral human dose on a body surface area basis) where drug administration was from either gestational day 7 or gestational day 16 until parturition. When maternal administration was confined to gestation only, there were no effects on bone physeal morphology in the offspring at any age.

8.2 Lactation

Risk Summary

Lactation studies have not been conducted to assess the presence of rabeprazole in human milk, the effects of rabeprazole on the breastfed infant, or the effects of rabeprazole on milk production. Rabeprazole is present in rat milk. The development and health benefits of breastfeeding should be considered along with the mother's clinical need for rabeprazole sodium and any potential adverse effects on the breastfed infant from rabeprazole sodium or from the underlying maternal condition.

8.4 Pediatric Use

The safety and effectiveness of rabeprazole sodium delayed-release tablets have been established in pediatric patients for adolescent patients 12 years of age and older for the treatment of symptomatic GERD. Use of rabeprazole sodium delayed-release tablets in this age group is supported by adequate and well controlled studies in adults and a multicenter, randomized, open-label, parallel-group study in 111 adolescent patients 12 to 16 years of age. Patients had a clinical diagnosis of symptomatic GERD, or suspected or endoscopically proven GERD and were randomized to either 10 mg or 20 mg once daily for up to 8 weeks for the evaluation of safety and efficacy. The adverse reaction profile in adolescent patients was similar to that of adults. The related reported adverse reactions that occurred in ≥2% of patients were headache (5%) and nausea (2%). There were no adverse reactions reported in these studies that were not previously observed in adults.

The safety and effectiveness of rabeprazole sodium delayed-release tablets have not been established in pediatric patients for:

• Healing of Erosive or Ulcerative GERD
• Maintenance of Healing of Erosive or Ulcerative GERD
• Treatment of Symptomatic GERD
• Healing of Duodenal Ulcers
• Helicobacter pylori Eradication to Reduce the Risk of Duodenal Ulcer Recurrence
• Treatment of Pathological Hypersecretory Conditions, Including Zollinger-Ellison Syndrome

Rabeprazole sodium delayed-release 20 mg tablets are not recommended for use in pediatric patients less than 12 years of age because the tablet strength exceeds the recommended dose for these patients [see Dosage and Administration (2)]. For pediatric patients 1 year to less than 12 years of age consider another rabeprazole formulation. The safety and effectiveness of a different dosage form and dosage strength of rabeprazole has been established in pediatric patients 1 to 11 years for the treatment of GERD.

Juvenile Animal Data

Studies in juvenile and young adult rats and dogs were performed. In juvenile animal studies rabeprazole sodium was administered orally to rats for up to 5 weeks and to dogs for up to 13 weeks, each commencing on Day 7 post-partum and followed by a 13-week recovery period. Rats were dosed at 5, 25, or 150 mg/kg/day and dogs were dosed at 3, 10, or 30 mg/kg/day. The data from these studies were comparable to those reported for young adult animals. Pharmacologically mediated changes, including increased serum gastrin levels and stomach changes, were observed at all dose levels in both rats and dogs. These observations were reversible over the 13-week recovery periods. Although body weights and/or crown-rump lengths were minimally decreased during dosing, no effects on the development parameters were noted in either juvenile rats or dogs.

When juvenile animals were treated for 28 days with a different PPI at doses equal to or greater than 34 times the daily oral human dose on a body surface area basis, overall growth was affected and treatment-related decreases in body weight (approximately 14%) and body weight gain, and decreases in femur weight and femur length were observed.

8.5 Geriatric Use

Of the total number of subjects (n=2009) in clinical studies of rabeprazole sodium delayed-release tablets, 19% were 65 years and over, while 4% were 75 years and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, 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

Administration of rabeprazole sodium delayed-release tablets to patients with mild to moderate hepatic impairment (Child-Pugh Class A and B, respectively) resulted in increased exposure and decreased elimination [see Clinical Pharmacology (12.3)]. No dosage adjustment is necessary in patients with mild to moderate hepatic impairment. There is no information in patients with severe hepatic impairment (Child-Pugh Class C). Avoid use of rabeprazole sodium delayed-release tablets in patients with severe hepatic impairment; however, if treatment is necessary, monitor patients for adverse reactions [see Warnings and Precautions (5), Adverse Reactions (6)].

12.1 Mechanism of Action

Rabeprazole belongs to a class of antisecretory compounds (substituted benzimidazole proton-pump inhibitors) that do not exhibit anticholinergic or histamine H2-receptor antagonist properties, but suppress gastric acid secretion by inhibiting the gastric H+, K+ATPase at the secretory surface of the gastric parietal cell. Because this enzyme is regarded as the acid (proton) pump within the parietal cell, rabeprazole has been characterized as a gastric proton-pump inhibitor. Rabeprazole blocks the final step of gastric acid secretion.

In gastric parietal cells, rabeprazole is protonated, accumulates, and is transformed to an active sulfenamide. When studied in vitro, rabeprazole is chemically activated at pH 1.2 with a half-life of 78 seconds. It inhibits acid transport in porcine gastric vesicles with a half-life of 90 seconds.

12.2 Pharmacodynamics

12.3 Pharmacokinetics

After oral administration of 20 mg rabeprazole sodium delayed-release tablets, peak plasma concentrations (Cmax) of rabeprazole occur over a range of 2 to 5 hours (Tmax). The rabeprazole Cmax and AUC are linear over an oral dose range of 10 mg to 40 mg. There is no appreciable accumulation when doses of 10 mg to 40 mg are administered every 24 hours; the pharmacokinetics of rabeprazole is not altered by multiple dosing.

12.4 Microbiology

The following in vitro data are available but the clinical significance is unknown.

Rabeprazole sodium, amoxicillin and clarithromycin as a three drug regimen has been shown to be active against most strains of Helicobacter pylori in vitro and in clinical infections [see Indications and Usage (1), Clinical Studies (14.5)].

12.5 Pharmacogenomics

In a clinical study in evaluating rabeprazole sodium delayed-release tablets in Japanese adult patients categorized by CYP2C19 genotype (n=6 per genotype category), gastric acid suppression was higher in poor metabolizers as compared to extensive metabolizers. This could be due to higher rabeprazole plasma levels in poor metabolizers. The clinical relevance of this is not known. Whether or not interactions of rabeprazole sodium with other drugs metabolized by CYP2C19 would be different between extensive metabolizers and poor metabolizers has not been studied.

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

In an 88/104-week carcinogenicity study in CD-1 mice, rabeprazole at oral doses up to 100 mg/kg/day did not produce any increased tumor occurrence. The highest tested dose produced a systemic exposure to rabeprazole (AUC) of 1.40 mcg•hr/mL which is 1.6 times the human exposure (plasma AUC0-∞ = 0.88 mcg•hr/mL) at the recommended dose for GERD (20 mg/day). In a 28-week carcinogenicity study in p53+/-transgenic mice, rabeprazole at oral doses of 20, 60, and 200 mg/kg/day did not cause an increase in the incidence rates of tumors but produced gastric mucosal hyperplasia at all doses. The systemic exposure to rabeprazole at 200 mg/kg/day is about 17 to 24 times the human exposure at the recommended dose for GERD. In a 104-week carcinogenicity study in Sprague-Dawley rats, males were treated with oral doses of 5, 15, 30 and 60 mg/kg/day and females with 5, 15, 30, 60, and 120 mg/kg/day. Rabeprazole produced gastric enterochromaffin-like (ECL) cell hyperplasia in male and female rats and ECL cell carcinoid tumors in female rats at all doses including the lowest tested dose. The lowest dose (5 mg/kg/day) produced a systemic exposure to rabeprazole (AUC) of about 0.1 mcg•hr/mL which is about 0.1 times the human exposure at the recommended dose for GERD. In male rats, no treatment related tumors were observed at doses up to 60 mg/kg/day producing a rabeprazole plasma exposure (AUC) of about 0.2 mcg•hr/mL (0.2 times the human exposure at the recommended dose for GERD).

Rabeprazole was positive in the Ames test, the Chinese hamster ovary cell (CHO/HGPRT) forward gene mutation test, and the mouse lymphoma cell (L5178Y/TK+/–) forward gene mutation test. Its demethylated-metabolite was also positive in the Ames test. Rabeprazole was negative in the in vitro Chinese hamster lung cell chromosome aberration test, the in vivo mouse micronucleus test, and the in vivo and ex vivo rat hepatocyte unscheduled DNA synthesis (UDS) tests.

Rabeprazole at intravenous doses up to 30 mg/kg/day (plasma AUC of 8.8 mcg•hr/mL, about 10 times the human exposure at the recommended dose for GERD) was found to have no effect on fertility and reproductive performance of male and female rats.

14.1 Healing of Erosive or Ulcerative GERD in Adults

In a U.S., multicenter, randomized, double-blind, placebo-controlled study, 103 patients were treated for up to eight weeks with placebo, 10 mg, 20 mg or 40 mg rabeprazole sodium delayed-release tablets once daily. For this and all studies of GERD healing, only patients with GERD symptoms and at least grade 2 esophagitis (modified Hetzel-Dent grading scale) were eligible for entry. Endoscopic healing was defined as grade 0 or 1. Each rabeprazole dose was significantly superior to placebo in producing endoscopic healing after four and eight weeks of treatment. The percentage of patients demonstrating endoscopic healing was as follows:

In addition, there was a statistically significant difference in favor of the rabeprazole sodium 10 mg, 20 mg, and 40 mg doses compared to placebo at Weeks 4 and 8 regarding complete resolution of GERD heartburn frequency (p≤0.026). All rabeprazole sodium groups reported significantly greater rates of complete resolution of GERD daytime heartburn severity compared to placebo at Weeks 4 and 8 (p≤0.036). Mean reductions from baseline in daily antacid dose were statistically significant for all rabeprazole sodium groups when compared to placebo at both Weeks 4 and 8 (p≤0.007).

In a North American multicenter, randomized, double-blind, active-controlled study of 336 patients, the percentage of patients healed at endoscopy after four and eight weeks of treatment was statistically superior in the patients treated with rabeprazole sodium delayed-release tablets compared to ranitidine:

A dose of 20 mg once daily of rabeprazole sodium delayed-release tablets was significantly more effective than ranitidine 150 mg four times daily in the percentage of patients with complete resolution of heartburn at Weeks 4 and 8 (p<0.001). Rabeprazole sodium was also more effective in complete resolution of daytime heartburn (p≤0.025), and nighttime heartburn (p≤0.012) at both Weeks 4 and 8, with significant differences by the end of the first week of the study.

The recommended dosage of rabeprazole sodium delayed-release tablets is 20 mg once daily for 4 to 8 weeks.

14.2 Long-Term Maintenance of Healing of Erosive or Ulcerative GERD in Adults

The long-term maintenance of healing in patients with erosive or ulcerative GERD previously healed with gastric antisecretory therapy was assessed in two U.S. multicenter, randomized, double-blind, placebo-controlled studies of identical design of 52 weeks duration. The two studies randomized 209 and 285 patients, respectively, to receive either 10 mg or 20 mg of rabeprazole sodium delayed-release tablets once daily or placebo. As demonstrated in Tables 10 and 11 below, patients treated with rabeprazole sodium delayed-release tablets were significantly superior to placebo in both studies with respect to the maintenance of healing of GERD and the proportions of patients remaining free of heartburn symptoms at 52 weeks. The recommended dosage of rabeprazole sodium delayed-release tablets is 20 mg once daily.

14.3 Treatment of Symptomatic GERD in Adults

Two U.S., multicenter, double-blind, placebo controlled studies were conducted in 316 adult patients with daytime and nighttime heartburn. Patients reported 5 or more periods of moderate to very severe heartburn during the placebo treatment phase the week prior to randomization. Patients were confirmed by endoscopy to have no esophageal erosions.

The percentage of heartburn free daytime and/or nighttime periods was greater with 20 mg rabeprazole sodium delayed-release tablets compared to placebo over the 4 weeks of study in Study RAB-USA-2 (47% vs. 23%) and Study RAB-USA-3 (52% vs. 28%). The mean decreases from baseline in average daytime and nighttime heartburn scores were significantly greater for rabeprazole sodium 20 mg as compared to placebo at week 4. Graphical displays depicting the daily mean daytime and nighttime scores are provided in Figures 2 to 5.

Figure 2: Mean Daytime Heartburn Scores RAB-USA-2

Figure 3: Mean Nighttime Heartburn Scores RAB-USA-2

Figure 4: Mean Daytime Heartburn Scores RAB-USA-3

Figure 5: Mean Nighttime Heartburn Scores RAB-USA-3

In addition, the combined analysis of these two studies showed 20 mg of rabeprazole sodium delayed-release tablets significantly improved other GERD-associated symptoms (regurgitation, belching, and early satiety) by week 4 compared with placebo (all p values < 0.005).

A dose of 20 mg rabeprazole sodium delayed-release tablets also significantly reduced daily antacid consumption versus placebo over 4 weeks (p<0.001).

The recommended dosage of rabeprazole sodium delayed-release tablets is 20 mg once daily for 4 weeks.

14.4 Healing of Duodenal Ulcers in Adults

In a U.S., randomized, double-blind, multicenter study assessing the effectiveness of 20 mg and 40 mg of rabeprazole sodium delayed-release tablets once daily versus placebo for healing endoscopically defined duodenal ulcers, 100 patients were treated for up to four weeks. Rabeprazole sodium was significantly superior to placebo in producing healing of duodenal ulcers. The percentages of patients with endoscopic healing are presented below:

At Weeks 2 and 4, significantly more patients in the rabeprazole sodium 20 and 40 mg groups reported complete resolution of ulcer pain frequency (p≤0.018), daytime pain severity (p≤0.023), and nighttime pain severity (p≤0.035) compared with placebo patients. The only exception was the 40 mg group versus placebo at Week 2 for duodenal ulcer pain frequency (p=0.094). Significant differences in resolution of daytime and nighttime pain were noted in both rabeprazole sodium groups relative to placebo by the end of the first week of the study. Significant reductions in daily antacid use were also noted in both rabeprazole sodium groups compared to placebo at Weeks 2 and 4 (p<0.001).

An international randomized, double-blind, active-controlled trial was conducted in 205 patients comparing 20 mg rabeprazole sodium delayed-release tablets once daily with 20 mg omeprazole once daily. The study was designed to provide at least 80% power to exclude a difference of at least 10% between rabeprazole sodium and omeprazole, assuming four-week healing response rates of 93% for both groups. In patients with endoscopically defined duodenal ulcers treated for up to four weeks, rabeprazole sodium was comparable to omeprazole in producing healing of duodenal ulcers. The percentages of patients with endoscopic healing at two and four weeks are presented below:

Rabeprazole sodium and omeprazole were comparable in providing complete resolution of symptoms.

The recommended dosage of rabeprazole sodium delayed-release tablets is 20 mg once daily for 4 weeks.

14.5 Helicobacter pylori Eradication in Patients with Peptic Ulcer Disease or Symptomatic Non-Ulcer Disease in Adults

The U.S. multicenter study was a double-blind, parallel-group comparison of rabeprazole sodium delayed-release tablets, amoxicillin, and clarithromycin for 3, 7, or 10 days vs. omeprazole, amoxicillin, and clarithromycin for 10 days. Therapy consisted of rabeprazole 20 mg twice daily, amoxicillin 1000 mg twice daily, and clarithromycin 500 mg twice daily (RAC) or omeprazole 20 mg twice daily, amoxicillin 1000 mg twice daily, and clarithromycin 500 mg twice daily (OAC). Patients with H. pylori infection were stratified in a 1:1 ratio for those with peptic ulcer disease (active or a history of ulcer in the past five years) [PUD] and those who were symptomatic but without peptic ulcer disease [NPUD], as determined by upper gastrointestinal endoscopy. The overall H. pylori eradication rates, defined as negative 13C-UBT for H. pylori ≥ 6 weeks from the end of the treatment are shown in the following table. The eradication rates in the 7-day and 10-day RAC regimens were found to be similar to 10-day OAC regimen using either the Intent-to-Treat (ITT) or Per-Protocol (PP) populations. Eradication rates in the RAC 3-day regimen were inferior to the other regimens.

The recommended dosage of rabeprazole sodium delayed-release tablets is 20 mg twice daily with amoxicillin and clarithromycin for 7 days.

14.6 Pathological Hypersecretory Conditions, Including Zollinger-Ellison Syndrome in Adults

Twelve patients with idiopathic gastric hypersecretion or Zollinger-Ellison syndrome have been treated successfully with rabeprazole sodium delayed-release tablets at doses from 20 to 120 mg for up to 12 months. Rabeprazole sodium produced satisfactory inhibition of gastric acid secretion in all patients and complete resolution of signs and symptoms of acid-peptic disease where present. Rabeprazole sodium also prevented recurrence of gastric hypersecretion and manifestations of acid-peptic disease in all patients. The high doses of rabeprazole sodium used to treat this small cohort of patients with gastric hypersecretion were well tolerated.

The recommended starting dosage of rabeprazole sodium delayed-release tablets is 60 mg once daily.