Omeprazole delayed-release capsules in combination with clarithromycin and amoxicillin, is indicated for treatment of patients with
H. pylori infection and duodenal ulcer disease (active or up to 1-year history) to eradicate
H. pylori in adults.
Omeprazole delayed-release capsules in combination with clarithromycin are indicated for treatment of patients with
H. pylori infection and duodenal ulcer disease to eradicate
H. pylori in adults.
Among patients who fail therapy, Omeprazole delayed-release capsules with clarithromycin are more likely to be associated with the development of clarithromycin resistance as compared with triple therapy. 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 (12.4) and the clarithromycin prescribing information, Microbiology section].
Omeprazole is indicated for the short-term treatment (4 to 8 weeks) of EE due to acid-mediated GERD that has been diagnosed by endoscopy in patients 2 years of age and older.
The efficacy of omeprazole used for longer than 8 weeks in patients with EE has not been established. If a patient does not respond to 8 weeks of treatment, an additional 4 weeks of treatment may be given. If there is recurrence of EE or GERD symptoms (e.g., heartburn), additional 4 to 8 week courses of Omeprazole may be considered.
- Swallow Omeprazole delayed-release capsules whole; do not chew.
- For patients unable to swallow an intact capsule, Omeprazole delayed-release capsules can be opened and administered as follows:
- Place one tablespoon of applesauce into a clean container (e.g., empty bowl). The applesauce used should not be hot and should be soft enough to be swallowed without chewing.
- Open the capsule.
- Carefully empty all of the pellets inside the capsule on the applesauce.
- Mix the pellets with the applesauce.
- Swallow applesauce and pellets immediately with a glass of cool water to ensure complete swallowing of the pellets. Do not chew or crush the pellets. Do not save the applesauce and pellets for future use.
Monotherapy
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 practice.
The safety data described below reflects exposure to Omeprazole delayed-release capsules in 3096 patients from worldwide clinical trials (465 patients from US studies and 2,631 patients from international studies). Indications clinically studied in US trials included duodenal ulcer, resistant ulcer, and Zollinger-Ellison syndrome. The international clinical trials were double blind and open-label in design. The most common adverse reactions reported (i.e., with an incidence rate ≥2%) from omeprazole-treated patients enrolled in these studies included headache (7%), abdominal pain (5%), nausea (4%), diarrhea (4%), vomiting (3%), and flatulence (3%).
Additional adverse reactions that were reported with an incidence ≥1% included acid regurgitation (2%), upper respiratory infection (2%), constipation (2%), dizziness (2%), rash (2%), asthenia (1%), back pain (1%), and cough (1%).
The clinical trial safety profile in patients greater than 65 years of age was similar to that in patients 65 years of age or less.
The clinical trial safety profile in pediatric patients who received omeprazole delayed-release capsules was similar to that in adult patients. Unique to the pediatric population, however, adverse reactions of the respiratory system were frequently reported in the 2 to 16 year age group (19%). In addition, accidental injuries were frequently reported in the 2 to 16 year age group (4%)
[see
Use in Specific Populations (8.4)].
Dual Therapy (omeprazole /clarithromycin)
Adverse reactions observed in controlled clinical trials using combination therapy with omeprazole and clarithromycin (n = 346) that differed from those previously described for omeprazole alone were taste perversion (15%), tongue discoloration (2%), rhinitis (2%), pharyngitis (1%) and flu-syndrome (1%). (For more information on clarithromycin, refer to the clarithromycin prescribing information, Adverse Reactions section.)
Triple Therapy (omeprazole /clarithromycin/amoxicillin)
The most frequent adverse reactions observed in clinical trials using combination therapy with omeprazole, clarithromycin, and amoxicillin (n = 274) were diarrhea (14%), taste perversion (10%), and headache (7%). None of these occurred at a higher frequency than that reported by patients taking antimicrobial agents alone. (For more information on clarithromycin or amoxicillin, refer to the respective prescribing information, Adverse Reactions sections.)
Risk Summary
There are no adequate and well-controlled studies with omeprazole in pregnant women. Available epidemiologic data fail to demonstrate an increased risk of major congenital malformations or other adverse pregnancy outcomes with first trimester omeprazole use. Reproduction studies in rats and rabbits resulted in dose-dependent embryo-lethality at omeprazole doses that were approximately 3.4 to 34 times an oral human dose of 40 mg (based on a body surface area for a 60 kg person).
Teratogenicity was not observed in animal reproduction studies with administration of oral esomeprazole (an enantiomer of omeprazole) magnesium in rats and rabbits during organogenesis with doses about 68 times and 42 times, respectively, an oral human dose of 40 mg esomeprazole or 40 mg omeprazole (based on body surface area for a 60 kg person). Changes in bone morphology were observed in offspring of rats dosed through most of pregnancy and lactation at doses equal to or greater than approximately 34 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole. When maternal administration was confined to gestation only, there were no effects on bone physeal morphology in the offspring at any age
[see
Data]
. The estimated background risks of major birth defects and miscarriage for the indicated population are unknown. All pregnancies have a background risk of birth defect, 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
Four published epidemiological studies compared the frequency of congenital abnormalities among infants born to women who used omeprazole during pregnancy with the frequency of abnormalities among infants of women exposed to H
2-receptor antagonists or other controls.
A population-based retrospective cohort epidemiological study from the Swedish Medical Birth Registry, covering approximately 99% of pregnancies, from 1995 to 99, reported on 955 infants (824 exposed during the first trimester with 39 of these exposed beyond first trimester, and 131 exposed after the first trimester) whose mothers used omeprazole during pregnancy. The number of infants exposed
in utero to omeprazole that had any malformation, low birth weight, low Apgar score, or hospitalization was similar to the number observed in this population. The number of infants born with ventricular septal defects and the number of stillborn infants was slightly higher in the omeprazole-exposed infants than the expected number in this population.
A population-based retrospective cohort study covering all live births in Denmark from 1996 to 2009, reported on 1,800 live births whose mothers used omeprazole during the first trimester of pregnancy and 837,317 live births whose mothers did not use any proton pump inhibitor. The overall rate of birth defects in infants born to mothers with first trimester exposure to omeprazole was 2.9% and 2.6% in infants born to mothers not exposed to any proton pump inhibitor during the first trimester.
A retrospective cohort study reported on 689 pregnant women exposed to either H
2-blockers or omeprazole in the first trimester (134 exposed to omeprazole) and 1,572 pregnant women unexposed to either during the first trimester. The overall malformation rate in offspring born to mothers with first trimester exposure to omeprazole, an H
2-blocker, or were unexposed was 3.6%, 5.5%, and 4.1% respectively.
A small prospective observational cohort study followed 113 women exposed to omeprazole during pregnancy (89% with first trimester exposures). The reported rate of major congenital malformations was 4% in the omeprazole group, 2% in controls exposed to non-teratogens, and 2.8% in disease-paired controls. Rates of spontaneous and elective abortions, preterm deliveries, gestational age at delivery, and mean birth weight were similar among the groups. Several studies have reported no apparent adverse short-term effects on the infant when single dose oral or intravenous omeprazole was administered to over 200 pregnant women as premedication for cesarean section under general anesthesia.
Animal Data
Omeprazole
Reproductive studies conducted with omeprazole in rats at oral doses up to 138 mg/kg/day (about 34 times an oral human dose of 40 mg on a body surface area basis) and in rabbits at doses up to 69.1 mg/kg/day (about 34 times an oral human dose of 40 mg on a body surface area basis) during organogenesis did not disclose any evidence for a teratogenic potential of omeprazole. In rabbits, omeprazole in a dose range of 6.9 to 69.1 mg/kg/day (about 3.4 to 34 times an oral human dose of 40 mg on a body surface area basis) administered during organogenesis produced dose-related increases in embryo-lethality, fetal resorptions, and pregnancy disruptions. In rats, dose-related embryo/fetal toxicity and postnatal developmental toxicity were observed in offspring resulting from parents treated with omeprazole at 13.8 to 138.0 mg/kg/day (about 3.4 to 34 times an oral human doses of 40 mg on a body surface area basis), administered prior to mating through the lactation period.
Esomeprazole
The data described below was generated from studies using esomeprazole, an enantiomer of omeprazole. The animal to human dose multiples are based on the assumption of equal systemic exposure to esomeprazole in humans following oral administration of either 40 mg esomeprazole or 40 mg omeprazole. No effects on embryo-fetal development were observed in reproduction studies with esomeprazole magnesium in rats at oral doses up to 280 mg/kg/day (about 68 times an oral human dose of 40 mg on a body surface area basis) or in rabbits at oral doses up to 86 mg/kg/day (about 42 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis) administered during organogenesis.
A pre- and postnatal developmental toxicity study in rats with additional endpoints to evaluate bone development was performed with esomeprazole magnesium at oral doses of 14 to 280 mg/kg/day (about 3.4 to 68 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). Neonatal/early postnatal (birth to weaning) survival was decreased at doses equal to or greater than 138 mg/kg/day (about 34 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). Body weight and body weight gain were reduced and neurobehavioral or general developmental delays in the immediate post-weaning timeframe were evident at doses equal to or greater than 69 mg/kg/day (about 17 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). In addition, 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 equal to or greater than 14 mg/kg/day (about 3.4 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). Physeal dysplasia in the femur was observed in offspring of rats treated with oral doses of esomeprazole magnesium at doses equal to or greater than 138 mg/kg/day (about 34 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis).
Effects on maternal bone were observed in pregnant and lactating rats in the pre- and postnatal toxicity study when esomeprazole magnesium was administered at oral doses of 14 to 280 mg/kg/day (about 3.4 to 68 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole 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 138 mg/kg/day (about 34 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis).
A pre- and postnatal development study in rats with esomeprazole strontium (using equimolar doses compared to esomeprazole magnesium study) produced similar results in dams and pups as described above.
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 esomeprazole magnesium at oral doses of 280 mg/kg/day (about 68 times an oral human dose of 40 mg on a body surface area basis) where esomeprazole 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.
Risk Summary
Limited data suggest omeprazole may be present in human milk. There are no clinical data on the effects of omeprazole on the breastfed infant or on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for Omeprazole delayed-release capsules and any potential adverse effects on the breastfed infant from Omeprazole delayed-release capsules or from the underlying maternal condition.
Juvenile Animal Data
Esomeprazole, an enantiomer of omeprazole, was shown to decrease body weight, body weight gain, femur weight, femur length, and overall growth at oral doses about 34 to 68 times a daily human dose of 40 mg esomeprazole or 40 mg omeprazole based on body surface area in a juvenile rat toxicity study. The animal to human dose multiples are based on the assumption of equal systemic exposure to esomeprazole in humans following oral administration of either 40 mg esomeprazole or 40 mg omeprazole.
A 28-day toxicity study with a 14-day recovery phase was conducted in juvenile rats with esomeprazole magnesium at doses of 70 to 280 mg/kg/day (about 17 to 68 times a daily oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). An increase in the number of deaths at the high dose of 280 mg/kg/day was observed when juvenile rats were administered esomeprazole magnesium from postnatal day 7 through postnatal day 35. In addition, doses equal to or greater than 140 mg/kg/day (about 34 times a daily oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis), produced treatment-related decreases in body weight (approximately 14%) and body weight gain, decreases in femur weight and femur length, and affected overall growth. Comparable findings described above have also been observed in this study with another esomeprazole salt, esomeprazole strontium, at equimolar doses of esomeprazole.
Antisecretory Activity
After oral administration, the onset of the antisecretory effect of omeprazole occurs within one hour, with the maximum effect occurring within two hours. Inhibition of secretion is about 50% of maximum at 24 hours and the duration of inhibition lasts up to 72 hours. The antisecretory effect thus lasts far longer than would be expected from the very short (less than one hour) plasma half-life, apparently due to prolonged binding to the parietal H
+/K
+ ATPase enzyme. When the drug is discontinued, secretory activity returns gradually, over 3 to 5 days. The inhibitory effect of omeprazole on acid secretion increases with repeated once-daily dosing, reaching a plateau after four days.
Results from numerous studies of the antisecretory effect of multiple doses of 20 mg and 40 mg of omeprazole in healthy subjects and patients are shown below. The "max" value represents determinations at a time of maximum effect (2 to 6 hours after dosing), while "min" values are those 24 hours after the last dose of omeprazole.
Table 5: Range of Mean Values from Multiple Studies of the Mean Antisecretory Effects of Omeprazole After Multiple Daily Dosing | Omeprazole 20 mg | Omeprazole 40 mg |
|---|
| Parameter | | Max | | Min | | Max | | Min |
|---|
| % Decrease in Basal Acid Output | | 78
Single Studies | | 58-80 | | 94
| | 80-93 |
| % Decrease in Peak Acid Output | | 79
| | 50-59 | | 88
| | 62-68 |
| % Decrease in 24-hr. Intragastric Acidity | | | | 80-97 | | | | 92-94 |
Single daily oral doses of omeprazole ranging from a dose of 10 mg to 40 mg have produced 100% inhibition of 24-hour intragastric acidity in some patients.
Serum Gastrin Effects
In studies involving more than 200 patients, serum gastrin levels increased during the first 1 to 2 weeks of once-daily administration of therapeutic doses of omeprazole in parallel with inhibition of acid secretion. No further increase in serum gastrin occurred with continued treatment. In comparison with histamine H
2-receptor antagonists, the median increases produced by 20 mg doses of omeprazole were higher (1.3 to 3.6 fold vs. 1.1 to 1.8 fold increase). Gastrin values returned to pretreatment levels, usually within 1 to 2 weeks after discontinuation of therapy.
Increased gastrin causes enterochromaffin-like cell hyperplasia and increased serum Chromogranin A (CgA) levels. The increased CgA levels may cause false positive results in diagnostic investigations for neuroendocrine tumors
[see
Warnings and Precautions (5.11)].
Enterochromaffin-like (ECL) Cell Effects
Human gastric biopsy specimens have been obtained from more than 3000 patients (both children and adults) treated with omeprazole in long-term clinical trials. The incidence of ECL cell hyperplasia in these studies increased with time; however, no case of ECL cell carcinoids, dysplasia, or neoplasia has been found in these patients. However, these studies are of insufficient duration and size to rule out the possible influence of long-term administration of omeprazole on the development of any premalignant or malignant conditions.
Other Effects
Systemic effects of omeprazole in the CNS, cardiovascular and respiratory systems have not been found to date. Omeprazole, given in oral doses of 30 or 40 mg for 2 to 4 weeks, had no effect on thyroid function, carbohydrate metabolism, or circulating levels of parathyroid hormone, cortisol, estradiol, testosterone, prolactin, cholecystokinin or secretin.
No effect on gastric emptying of the solid and liquid components of a test meal was demonstrated after a single dose of omeprazole 90 mg. In healthy subjects, a single intravenous dose of omeprazole (0.35 mg/kg) had no effect on intrinsic factor secretion. No systematic dose-dependent effect has been observed on basal or stimulated pepsin output in humans.
However, when intragastric pH is maintained at 4.0 or above, basal pepsin output is low, and pepsin activity is decreased. As do other agents that elevate intragastric pH, omeprazole administered for 14 days in healthy subjects produced a significant increase in the intragastric concentrations of viable bacteria. The pattern of the bacterial species was unchanged from that commonly found in saliva. All changes resolved within three days of stopping treatment.
The course of Barrett's esophagus in 106 patients was evaluated in a U.S. double-blind controlled study of omeprazole 40 mg twice daily for 12 months followed by 20 mg twice daily for 12 months or ranitidine 300 mg twice daily for 24 months. No clinically significant impact on Barrett's mucosa by antisecretory therapy was observed. Although neosquamous epithelium developed during antisecretory therapy, complete elimination of Barrett's mucosa was not achieved. No significant difference was observed between treatment groups in development of dysplasia in Barrett's mucosa and no patient developed esophageal carcinoma during treatment. No significant differences between treatment groups were observed in development of ECL cell hyperplasia, corpus atrophic gastritis, corpus intestinal metaplasia, or colon polyps exceeding 3 mm in diameter.
Absorption
Omeprazole delayed-release capsules contain an enteric-coated granule formulation of omeprazole (because omeprazole is acid-labile), so that absorption of omeprazole begins only after the granules leave the stomach. Absorption is rapid, with peak plasma concentrations of omeprazole occurring within 0.5 to 3.5 hours. Peak plasma concentrations of omeprazole and AUC are approximately proportional to doses up to 40 mg, but because of a saturable first-pass effect, a greater than linear response in peak plasma concentration and AUC occurs with doses greater than 40 mg. Absolute bioavailability (compared with intravenous administration) is about 30 to 40% at doses of 20 to 40 mg, due in large part to presystemic metabolism. In healthy subjects the plasma half-life is 0.5 to 1 hour, and the total body clearance is 500 to 600 mL/min.
Based on a relative bioavailability study, the AUC and C
max of Omeprazole delayed-release capsules for delayed-release oral suspension were 87% and 88% of those for Omeprazole delayed-release capsules, respectively.
The bioavailability of omeprazole increases slightly upon repeated administration of Omeprazole delayed-release capsules.
The systemic exposure (C
max and AUC) are similar when a 40 mg Omeprazole delayed-release capsules is administered with and without applesauce.
However, administration of a 20 mg Omeprazole delayed-release capsules with applesauce, results in a mean 25% reduction in C
max without a significant change in AUC compared to administration without applesauce. The clinical relevance of this finding is unknown.
Distribution
Protein binding is approximately 95%.
Elimination
Metabolism
Omeprazole is extensively metabolized by the cytochrome P450 (CYP) enzyme system. The major part of its metabolism is dependent on the polymorphically expressed CYP2C19, responsible for the formation of hydroxyomeprazole, the major metabolite in plasma. The remaining part is dependent on another specific isoform, CYP3A4, responsible for the formation of omeprazole sulphone.
Excretion
Following single dose oral administration of a buffered solution of omeprazole, little if any unchanged drug was excreted in urine. The majority of the dose (about 77%) was eliminated in urine as at least six metabolites. Two were identified as hydroxyomeprazole and the corresponding carboxylic acid. The remainder of the dose was recoverable in feces. This implies a significant biliary excretion of the metabolites of omeprazole. Three metabolites have been identified in plasma the sulfide and sulfone derivatives of omeprazole, and hydroxyomeprazole. These metabolites have very little or no antisecretory activity.
Combination Therapy with Antimicrobials
Omeprazole 40 mg daily was given in combination with clarithromycin 500 mg every 8 hours to healthy adult male subjects. The steady state plasma concentrations of omeprazole were increased (C
max, AUC
0-24, and T
1/2 increases of 30%, 89% and 34% respectively) by the concomitant administration of clarithromycin. The observed increases in omeprazole plasma concentration were associated with the following pharmacological effects. The mean 24-hour gastric pH value was 5.2 when omeprazole was administered alone and 5.7 when co-administered with clarithromycin.
The plasma concentrations of clarithromycin and 14-hydroxy-clarithromycin were increased by the concomitant administration of omeprazole. For clarithromycin, the mean C
max was 10% greater, the mean C
min was 27% greater, and the mean AUC
0-8 was 15% greater when clarithromycin was administered with omeprazole than when clarithromycin was administered alone. Similar results were seen for 14-hydroxy-clarithromycin, the mean C
max was 45% greater, the mean C
min was 57% greater, and the mean AUC
0-8 was 45% greater. Clarithromycin concentrations in the gastric tissue and mucus were also increased by concomitant administration of omeprazole.
Table 6: Clarithromycin Tissue Concentrations 2 hours after Dose
Mean ± SD (μg/g)
| Tissue | Clarithromycin | Clarithromycin + Omeprazole |
|---|
| Antrum | 10.48 ± 2.01 (n = 5) | 19.96 ± 4.71 (n = 5) |
| Fundus | 20.81 ± 7.64 (n = 5) | 24.25 ± 6.37 (n = 5) |
| Mucus | 4.15 ± 7.74 (n = 4) | 39.29 ± 32.79 (n = 4) |
Specific Populations
Age: Geriatric Population
The elimination rate of omeprazole was somewhat decreased in the elderly, and bioavailability was increased. Omeprazole was 76% bioavailable when a single 40 mg oral dose of omeprazole (buffered solution) was administered to healthy elderly volunteers, versus 58% in young volunteers given the same dose. Nearly 70% of the dose was recovered in urine as metabolites of omeprazole and no unchanged drug was detected. The plasma clearance of omeprazole was 250 mL/min (about half that of young volunteers) and its plasma half-life averaged one hour, about twice that of young healthy volunteers.
Age: Pediatric Population
2 to 16 Years of Age
The pharmacokinetics of omeprazole have been investigated in pediatric patients 2 to 16 years of age:
Table 7: Pharmacokinetic Parameters of Omeprazole Following Single and Repeated Oral Administration in Pediatric Populations Compared with Adults| Single or Repeated Oral Dosing /Parameter | Children
Data from single and repeated dose studies. Doses of 10, 20 and 40 mg omeprazole as enteric-coated granules. ≤ 20 kg
2-5 years
10 mg
| Children
> 20 kg
6-16 years
20 mg
| Adults
Data from a single and repeated dose study. Doses of 10, 20 and 40 mg omeprazole as enteric-coated granules. (mean 76 kg)
23-29 years (n=12)
|
|---|
| Single Dosing |
| C
max Plasma concentration adjusted to an oral dose of 1 mg/kg. (ng/mL)
| 288 (n=10) | 495 (n=49) | 668 |
| AUC
(ng∙h/mL)
| 511 (n=7) | 1140 (n=32) | 1220 |
| Repeated Dosing |
| C
max (ng/mL)
| 539 (n=4) | 851 (n=32) | 1458 |
| AUC
(ng∙h/mL)
| 1179 (n=2) | 2276 (n=23) | 3352 |
Following comparable mg/kg doses of omeprazole, younger children (2 to 5 years of age) have lower AUCs than children 6 to 16 years of age or adults; AUCs of the latter two groups did not differ
[see
Dosage and Administration (2)].
Race/Ethnicity
[See
Clinical Pharmacology (12.5)].
Renal Impairment
In patients with chronic renal impairment (creatinine clearance between 10 and 62 mL/min/1.73 m
2), the disposition of omeprazole was very similar to that in healthy subjects, although there was a slight increase in bioavailability. Because urinary excretion is a primary route of excretion of omeprazole metabolites, their elimination slowed in proportion to the decreased creatinine clearance. This increase in bioavailability is not considered to be clinically meaningful.
Hepatic Impairment
In patients with chronic hepatic disease classified as Child-Pugh Class A (n=3), B (n=4) and C (n=1), the bioavailability increased to approximately 100% compared to healthy subjects, reflecting decreased first-pass effect, and the plasma half-life of the drug increased to nearly 3 hours compared with the half-life in healthy subjects of 0.5 to 1 hour. Plasma clearance averaged 70 mL/min, compared with a value of 500 to 600 mL/min in healthy subjects
[see
Dosage and Administration (2.1),
Use in Specific Populations (8.6)].
Drug Interaction Studies
Effect of Omeprazole on Other Drugs
Omeprazole is a time-dependent inhibitor of CYP2C19 and can increase the systemic exposure of co-administered drugs that are CYP2C19 substrates. In addition, administration of omeprazole increases intragastric pH and can alter the systemic exposure of certain drugs that exhibit pH-dependent solubility.
Antiretrovirals
For some antiretroviral drugs, such as rilpivirine, atazanavir and nelfinavir, decreased serum concentrations have been reported when given together with omeprazole
[see
Drug Interactions (7)].
Rilpivirine: Following multiple doses of rilpivirine (150 mg, daily) and omeprazole (20 mg, daily), AUC was decreased by 40%, C
max by 40%, and C
min by 33% for rilpivirine.
Nelfinavir: Following multiple doses of nelfinavir (1250 mg, twice daily) and omeprazole (40 mg daily), AUC was decreased by 36% and 92%, C
max by 37% and 89% and C
min by 39% and 75% respectively for nelfinavir and M8.
Atazanavir: Following multiple doses of atazanavir (400 mg, daily) and omeprazole (40 mg, daily, 2 hours before atazanavir), AUC was decreased by 94%, C
max by 96%, and C
min by 95%.
Saquinavir: Following multiple dosing of saquinavir/ritonavir (1000/100 mg) twice daily for 15 days with omeprazole 40 mg daily co-administered days 11 to 15. AUC was increased by 82%, C
max by 75%, and C
min by 106%. The mechanism behind this interaction is not fully elucidated. Therefore, clinical and laboratory monitoring for saquinavir toxicity is recommended during concurrent use with Omeprazole delayed-release capsules.
Clopidogrel
In a crossover clinical study, 72 healthy subjects were administered clopidogrel (300 mg loading dose followed by 75 mg per day) alone and with omeprazole (80 mg at the same time as clopidogrel) for 5 days. The exposure to the active metabolite of clopidogrel was decreased by 46% (Day 1) and 42% (Day 5) when clopidogrel and omeprazole were administered together.
Results from another crossover study in healthy subjects showed a similar pharmacokinetic interaction between clopidogrel (300 mg loading dose/75 mg daily maintenance dose) and omeprazole 80 mg daily when co-administered for 30 days. Exposure to the active metabolite of clopidogrel was reduced by 41% to 46% over this time period.
In another study, 72 healthy subjects were given the same doses of clopidogrel and 80 mg omeprazole but the drugs were administered 12 hours apart; the results were similar, indicating that administering clopidogrel and omeprazole at different times does not prevent their interaction
[see
Warnings and Precautions (5.7),
Drug Interactions (7)].
Mycophenolate Mofetil
Administration of omeprazole 20 mg twice daily for 4 days and a single 1000 mg dose of MMF approximately one hour after the last dose of omeprazole to 12 healthy subjects in a cross-over study resulted in a 52% reduction in the C
max and 23% reduction in the AUC of MPA
[see
Drug Interactions (7)].
Cilostazol
Omeprazole acts as an inhibitor of CYP2C19. Omeprazole, given in doses of 40 mg daily for one week to 20 healthy subjects in cross-over study, increased C
max and AUC of cilostazol by 18% and 26% respectively. The C
max and AUC of one of the active metabolites, 3,4-dihydro-cilostazol, which has 4-7 times the activity of cilostazol, were increased by 29% and 69%, respectively. Co-administration of cilostazol with omeprazole is expected to increase concentrations of cilostazol and the above mentioned active metabolite
[see
Drug Interactions (7)].
Diazepam
Concomitant administration of omeprazole 20 mg once daily and diazepam 0.1 mg/kg given intravenously resulted in 27% decrease in clearance and 36% increase in diazepam half-life
[see
Drug Interactions (7)].
Digoxin
Concomitant administration of omeprazole 20 mg once daily and digoxin in healthy subjects increased the bioavailability of digoxin by 10% (30% in two subjects)
[see
Drug Interactions (7)]
.
Effect of Other Drugs on Omeprazole
Voriconazole
Concomitant administration of omeprazole and voriconazole (a combined inhibitor of CYP2C19 and CYP3A4) resulted in more than doubling of the omeprazole exposure. When voriconazole (400 mg every 12 hours for one day, followed by 200 mg once daily for 6 days) was given with omeprazole (40 mg once daily for 7 days) to healthy subjects, the steady-state C
max and AUC
0-24 of omeprazole significantly increased: an average of 2 times (90% CI: 1.8, 2.6) and 4 times (90% CI: 3.3, 4.4), respectively, as compared to when omeprazole was given without voriconazole
[see
Drug Interactions (7)].
Helicobacter pylori
Susceptibility testing of
H. pylori isolates was performed for amoxicillin and clarithromycin using agar dilution methodology
1, and minimum inhibitory concentrations (MICs) were determined.
Standardized susceptibility test procedures require the use of laboratory control microorganisms to control the technical aspects of the laboratory procedures.
Pretreatment Resistance
Clarithromycin pretreatment resistance rates were 3.5% (4/113) in the omeprazole/clarithromycin dual therapy studies (4 and 5) and 9.3% (41/439) in omeprazole/clarithromycin/amoxicillin triple therapy studies (1, 2 and 3).
Amoxicillin pretreatment susceptible isolates (≤ 0.25 μg/mL) were found in 99.3% (436/439) of the patients in the omeprazole/clarithromycin/amoxicillin triple therapy studies (1, 2, and 3). Amoxicillin pretreatment minimum inhibitory concentrations (MICs) > 0.25 μg/mL occurred in 0.7% (3/439) of the patients, all of whom were in the clarithromycin and amoxicillin study arm. One patient had an unconfirmed pretreatment amoxicillin minimum inhibitory concentration (MIC) of > 256 μg/mL by Etest
®.
Table 8: Clarithromycin Susceptibility Test Results and Clinical/Bacteriological Outcomes| Clarithromycin Susceptibility Test Results and Clinical/Bacteriological Outcomes
Includes only patients with pretreatment clarithromycin susceptibility test results. |
|---|
| Clarithromycin Pretreatment Results | Clarithromycin Post-treatment Results |
|---|
| H. pylori negative – eradicated
| H. pylori positive – not eradicated
Post-treatment susceptibility results
|
|---|
| | S
Susceptible (S) MIC ≤ 0.25 μg/mL, Intermediate (I) MIC 0.5-1.0 μg/mL, Resistant (R) MIC ≥ 2 μg/mL. | I
| R
| No MIC |
|---|
| Dual Therapy – (omeprazole 40 mg once daily/clarithromycin 500 three times daily for 14 days followed by omeprazole 20 mg once daily for another 14 days) (Studies 4, 5) |
| Susceptible
| 108 | 72 | 1 | | 26 | 9 |
| Intermediate
| 1 | | | | 1 | |
| Resistant
| 4 | | | | 4 | |
| Triple Therapy – (omeprazole 20 mg twice daily/clarithromycin 500 mg twice daily/amoxicillin 1 g twice daily for 10 days – Studies 1, 2, 3; followed by omeprazole 20 mg once daily for another 18 days – Studies 1, 2) |
| Susceptible
| 171 | 153 | 7 | | 3 | 8 |
| Intermediate
| | | | | | |
| Resistant
| 14 | 4 | 1 | | 6 | 3 |
Patients not eradicated of
H. pylori following omeprazole/clarithromycin/amoxicillin triple therapy or omeprazole/clarithromycin dual therapy will likely have clarithromycin resistant
H. pylori isolates. Therefore, clarithromycin susceptibility testing should be done, if possible. Patients with clarithromycin resistant
H. pylori should not be treated with any of the following: omeprazole/clarithromycin dual therapy, omeprazole/clarithromycin/amoxicillin triple therapy, or other regimens which include clarithromycin as the sole antimicrobial agent.
Amoxicillin Susceptibility Test Results and Clinical/Bacteriological Outcomes
In the triple therapy clinical trials, 84.9% (157/185) of the patients in the omeprazole/clarithromycin/amoxicillin treatment group who had pretreatment amoxicillin susceptible MICs (≤ 0.25 μg/mL) were eradicated of
H. pylori and 15.1% (28/185) failed therapy. Of the 28 patients who failed triple therapy, 11 had no post-treatment susceptibility test results and 17 had post-treatment
H. pylori isolates with amoxicillin susceptible MICs. Eleven of the patients who failed triple therapy also had post-treatment
H. pylori isolates with clarithromycin resistant MICs.
Susceptibility Test for Helicobacter pylori
For susceptibility testing information about
Helicobacter pylori, see Microbiology section in prescribing information for clarithromycin and amoxicillin.
Effects on Gastrointestinal Microbial Ecology
Decreased gastric acidity due to any means including proton pump inhibitors, increases gastric counts of bacteria normally present in the gastrointestinal tract. Treatment with proton pump inhibitors may lead to slightly increased risk of gastrointestinal infections such as
Salmonella and
Campylobacter and, in hospitalized patients, possibly also
Clostridium difficile.
Triple Therapy (omeprazole/clarithromycin/amoxicillin)
Three U.S., randomized, double-blind clinical studies in patients with
H. pylori infection and duodenal ulcer disease (n = 558) compared omeprazole plus clarithromycin plus amoxicillin with clarithromycin plus amoxicillin. Two studies (1 and 2) were conducted in patients with an active duodenal ulcer, and the other study (3) was conducted in patients with a history of a duodenal ulcer in the past 5 years but without an ulcer present at the time of enrollment. The dose regimen in the studies was omeprazole 20 mg twice daily plus clarithromycin 500 mg twice daily plus amoxicillin 1 g twice daily for 10 days; or clarithromycin 500 mg twice daily plus amoxicillin 1 g twice daily for 10 days. In studies 1 and 2, patients who took the omeprazole regimen also received an additional 18 days of omeprazole 20 mg once daily. Endpoints studied were eradication of
H. pylori and duodenal ulcer healing (studies 1 and 2 only).
H. pylori status was determined by CLOtest
®, histology and culture in all three studies. For a given patient,
H. pylori was considered eradicated if at least two of these tests were negative, and none was positive.
The combination of omeprazole plus clarithromycin plus amoxicillin was effective in eradicating
H. pylori.
Table 9: Per-Protocol and Intent-to-Treat H. pylori Eradication Rates % of Patients Cured [95% Confidence Interval] | Omeprazole + clarithromycin + amoxicillin | Clarithromycin + amoxicillin |
|---|
| Per-Protocol
Patients were included in the analysis if they had confirmed duodenal ulcer disease (active ulcer, studies 1 and 2; history of ulcer within 5 years, study 3) and
H. pylori infection at baseline defined as at least two of three positive endoscopic tests from CLOtest
®, histology, and/or culture. Patients were included in the analysis if they completed the study. Additionally, if patients dropped out of the study due to an adverse event related to the study drug, they were included in the analysis as failures of therapy. The impact of eradication on ulcer recurrence has not been assessed in patients with a past history of ulcer.
| Intent-to-Treat
Patients were included in the analysis if they had documented
H. pylori infection at baseline and had confirmed duodenal ulcer disease. All dropouts were included as failures of therapy.
| Per-Protocol
| Intent-to-Treat
|
|---|
| Study 1 | 77
(p < 0.05) versus clarithromycin plus amoxicillin. [64, 86] (n = 64)
| 69
[57, 79] (n = 80)
| 43 [31, 56] (n = 67) | 37 [27, 48] (n = 84) |
| Study 2 | 78
[67, 88] (n = 65)
| 73
[61, 82] (n = 77)
| 41 [29, 54] (n = 68) | 36 [26, 47] (n = 83) |
| Study 3 | 90
[80, 96] (n = 69)
| 83
[74, 91] (n = 84)
| 33 [24, 44] (n = 93) | 32 [23, 42] (n = 99) |
Dual Therapy (omeprazole /clarithromycin)
Four randomized, double-blind, multi-center studies (4, 5, 6, and 7) evaluated omeprazole 40 mg once daily plus clarithromycin 500 mg three times daily for 14 days, followed by omeprazole 20 mg once daily, (Studies 4, 5, and 7) or by omeprazole 40 mg once daily (Study 6) for an additional 14 days in patients with active duodenal ulcer associated with
H. pylori. Studies 4 and 5 were conducted in the U.S. and Canada and enrolled 242 and 256 patients, respectively.
H. pylori infection and duodenal ulcer were confirmed in 219 patients in Study 4 and 228 patients in Study 5. These studies compared the combination regimen to omeprazole and clarithromycin monotherapies. Studies 6 and 7 were conducted in Europe and enrolled 154 and 215 patients, respectively.
H. pylori infection and duodenal ulcer were confirmed in 148 patients in Study 6 and 208 patients in Study 7. These studies compared the combination regimen with omeprazole monotherapy. The results for the efficacy analyses for these studies are described below.
H. pylori eradication was defined as no positive test (culture or histology) at 4 weeks following the end of treatment, and two negative tests were required to be considered eradicated of
H. pylori. In the per-protocol analysis, the following patients were excluded: dropouts, patients with missing
H. pylori tests post-treatment, and patients that were not assessed for
H. pylori eradication because they were found to have an ulcer at the end of treatment.
The combination of omeprazole and clarithromycin was effective in eradicating
H. pylori.
Table 10: H. pylori Eradication Rates (Per-Protocol Analysis at 4 to 6 Weeks) % of Patients Cured [95%Confidence Interval] | Omeprazole + Clarithromycin | Omeprazole | Clarithromycin |
|---|
| U.S. Studies | | | |
| Study 4 | 74 [60, 85]
Statistically significantly higher than clarithromycin monotherapy (p < 0.05). ,Statistically significantly higher than omeprazole monotherapy (p < 0.05). (n = 53)
| 0 [0, 7]
(n = 54)
| 31 [18, 47]
(n = 42)
|
| Study 5 | 64 [51, 76]
, (n = 61)
| 0 [0, 6]
(n = 59)
| 39 [24, 55]
(n = 44)
|
| Non U.S. Studies | | | |
| Study 6 | 83 [71, 92]
(n = 60)
| 1 [0, 7]
(n = 74)
| N/A |
| Study 7 | 74 [64, 83]
(n = 86)
| 1 [0, 6]
(n = 90)
| N/A |
Ulcer healing was not significantly different when clarithromycin was added to omeprazole therapy compared with omeprazole therapy alone.
The combination of omeprazole and clarithromycin was effective in eradicating
H. pylori and reduced duodenal ulcer recurrence.
Table 11: Duodenal Ulcer Recurrence Rates by H. pylori Eradication Status % of Patients with Ulcer Recurrence | H. pylori eradicated
H. pylori eradication status assessed at same time point as ulcer recurrence.
| H. pylori not eradicated
|
|---|
| U.S. Studies
Combined results for omeprazole + clarithromycin, omeprazole, and clarithromycin treatment arms. | | |
| 6 months post-treatment | | |
| Study 4 | 35
(p ≤ 0.01) versus proportion with duodenal ulcer recurrence who were not
H. pylori eradicated.
(n = 49)
| 60
(n = 88)
|
| Study 5 | 8
(n = 53)
| 60
(n = 106)
|
| Non U.S. Studies
Combined results for omeprazole + clarithromycin and omeprazole treatment arms. | | |
| 6 months post-treatment | | |
| Study 6 | 5
(n = 43)
| 46
(n = 78)
|
| Study 7 | 6
(n = 53)
| 43
(n = 107)
|
| 12 months post-treatment | | |
| Study 6 | 5
(n = 39)
| 68
(n = 71)
|
Treatment of Symptomatic GERD
The effectiveness of omeprazole for the treatment of symptomatic GERD in pediatric patients 2 to 16 years of age is based in part on data obtained from pediatric patients in an uncontrolled clinical study.
The study enrolled 113 pediatric patients 2 to 16 years of age with a history of symptoms suggestive of symptomatic GERD. Patients were administered a single dose of omeprazole (10 mg or 20 mg, based on body weight) for 4 weeks either as an intact capsule or as an open capsule in applesauce. Successful response was defined as no moderate or severe episodes of either pain-related symptoms or vomiting/regurgitation during the last 4 days of treatment. Results showed success rates of 60% (9/15; 10 mg omeprazole) and 59% (58/98; 20 mg omeprazole), respectively.
Treatment of EE due to Acid-Mediated GERD
In an uncontrolled, open-label dose-titration study, for the treatment of EE in pediatric patients 1 to 16 years of age required doses that ranged from 0.7 to 3.5 mg/kg/day (80 mg/day). Doses were initiated at 0.7 mg/kg/day. Doses were increased in increments of 0.7 mg/kg/day (if intraesophageal pH showed a pH of < 4 for less than 6% of a 24-hour study). After titration, patients remained on treatment for 3 months. Forty-four percent of the patients were healed on a dose of 0.7 mg/kg body weight; most of the remaining patients were healed with 1.4 mg/kg after an additional 3 months' treatment. EE was healed in 51 of 57 (90%) children who completed the first course of treatment in the healing phase of the study. In addition, after 3 months of treatment, 33% of the children had no overall symptoms, 57% had mild reflux symptoms, and 40% had less frequent regurgitation/vomiting.
Maintenance of Healing of EE due to Acid-Mediated GERD
In an uncontrolled, open-label study of maintenance of healing of EE in 46 pediatric patients 1 to 16 years of age, 54% of patients required half the healing dose. The remaining patients increased the healing dose (0.7 to a maximum of 2.8 mg/kg/day) either for the entire maintenance period, or returned to half the dose before completion. Of the 46 patients who entered the maintenance phase, 19 (41%) had no relapse during follow-up (range 4 to 25 months). In addition, maintenance therapy in EE patients resulted in 63% of patients having no overall symptoms.
Adverse Reactions
Advise patients to report to their healthcare provider if they experience any signs or symptoms consistent with:
- Hypersensitivity reactions
[see
Contraindications (4)].
- 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)].
- Cutaneous and Systemic Lupus Erythematosus
[see
Warnings and Precautions (5.6)]
- Cyanocobalamin (Vitamin B-12) Deficiency
[see
Warnings and Precautions (5.8)].
- Hypomagnesemia
[see
Warnings and Precautions (5.9)].
Drug Interactions
Advise patients to report to their healthcare provider if they start treatment with clopidogrel, St. John's Wort or rifampin; or, if they take high-dose methotrexate
[see
Warnings and Precautions (5.7,
5.10,
5.12)].
Administration
- Take Omeprazole delayed-release capsules before meals.
- Antacids may be used concomitantly with Omeprazole delayed-release capsules.
- Missed doses: If a dose is missed, administer as soon as possible. However, if the next scheduled dose is due, do not take the missed dose, and take the next dose on time. Do not take two doses at one time to make up for a missed dose.
Omeprazole delayed-release capsules
- Swallow Omeprazole delayed-release capsules whole; do not chew.
- For patients unable to swallow an intact capsule, Omeprazole delayed-release capsules can be opened and administered in applesauce, as described in the Medication Guide.
Manufactured for: Breckenridge Pharmaceutical, Inc., Berlin, CT 06037
Manufactured by: Towa Pharmaceutical Europe, S.L., Martorelles (Barcelona), Spain
711655-03
Marketed/Packaged by:
GSMS, Inc.
Camarillo, CA USA 93012