Mechanism of Action
Esomeprazole is a proton pump inhibitor that suppresses
gastric acid secretion by specific inhibition of the H+/K+-ATPase in the
gastric parietal cell. The S- and R-isomers of omeprazole are protonated and
converted in the acidic compartment of the parietal cell forming the active
inhibitor, the achiral sulphenamide. By acting specifically on the proton pump,
esomeprazole blocks the final step in acid production, thus reducing gastric
acidity. This effect is dose-related up to a daily dose of 20 to 40 mg and
leads to inhibition of gastric acid secretion.
Pharmacodynamics
Antisecretory Activity
The effect of NEXIUM on intragastric pH was determined in patients
with symptomatic gastroesophageal reflux disease in two separate studies. In
the first study of 36 patients, NEXIUM 40 mg and 20 mg capsules were
administered over 5 days. The results are shown in the following table:
Table 3 : Effect on Intragastric pH on Day 5 (N=36)
| Parameter |
NEXIUM
40 mg |
NEXIUM
20 mg |
| % Time Gastric |
70%* |
53% |
| pH > 4†(Hours) |
(16.8 h) |
(12.7 h) |
| Coefficient of variation |
26% |
37% |
| Median 24 Hour pH |
4.9* |
4.1 |
| Coefficient of variation |
16% |
27% |
† Gastric pH was measured over a 24-hour period
*p < 0.01 NEXIUM 40 mg vs. NEXIUM 20 mg |
In a second study, the effect on intragastric pH of NEXIUM 40 mg administered
once daily over a five day period was similar to the first study, (% time with
pH > 4 was 68% or 16.3 hours).
Serum Gastrin Effects
The effect of NEXIUM on serum gastrin concentrations was
evaluated in approximately 2,700 patients in clinical trials up to 8 weeks and
in over 1,300 patients for up to 6 to 12 months. The mean fasting gastrin level
increased in a dose-related manner. This increase reached a plateau within two
to three months of therapy and returned to baseline levels within four weeks
after discontinuation of therapy.
Enterochromaffin-like (ECL) Cell Effects
In 24-month carcinogenicity studies of omeprazole in rats, a dose-related significant
occurrence of gastric ECL cell carcinoid tumors and ECL cell hyperplasia was
observed in both male and female animals [see Nonclinical
Toxicology]. Carcinoid tumors have also been observed in rats subjected
to fundectomy or long-term treatment with other proton pump inhibitors or high
doses of H2-receptor antagonists.
Human gastric biopsy specimens have been obtained from more
than 3,000 patients 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.
In over 1,000 patients treated with NEXIUM (10, 20 or 40
mg/day) up to 6 to 12 months, the prevalence of ECL cell hyperplasia increased
with time and dose. No patient developed ECL cell carcinoids, dysplasia, or
neoplasia in the gastric mucosa.
Endocrine Effects
NEXIUM had no effect on thyroid function when given in oral
doses of 20 or 40 mg for 4 weeks. Other effects of NEXIUM on the endocrine
system were assessed using omeprazole studies. Omeprazole given in oral doses
of 30 or 40 mg for 2 to 4 weeks had no effect on carbohydrate metabolism, circulating
levels of parathyroid hormone, cortisol, estradiol, testosterone, prolactin,
cholecystokinin, or secretin.
Pharmacokinetics
Absorption
NEXIUM Delayed-Release Capsules and NEXIUM For
Delayed-Release Oral Suspension contain a bioequivalent enteric-coated granule
formulation of esomeprazole magnesium. Bioequivalency is based on a single dose
(40 mg) study in 94 healthy male and female volunteers under fasting condition.
After oral administration peak plasma levels (C max) occur at approximately 1.5
hours (Tmax). The Cmax increases proportionally when the dose is increased, and
there is a three-fold increase in the area under the plasma concentration-time curve
(AUC) from 20 to 40 mg. At repeated once-daily dosing with 40 mg, the systemic
bioavailability is approximately 90% compared to 64% after a single dose of 40
mg. The mean exposure (AUC) to esomeprazole increases from 4.32 μmol*hr/L on
Day 1 to 11.2 μmol*hr/L on Day 5 after 40 mg once daily dosing.
The AUC after administration of a single 40 mg dose of
NEXIUM is decreased by 43% to 53% after food intake compared to fasting
conditions. NEXIUM should be taken at least one hour before meals.
The pharmacokinetic profile of NEXIUM was determined in 36
patients with symptomatic gastroesophageal reflux disease following repeated
once daily administration of 20 mg and 40 mg capsules of NEXIUM over a period
of five days. The results are shown in the following table:
Table 4 : Pharmacokinetic Parameters of NEXIUM on Day 5 Following
Oral Dosing for 5 Days
| Parameter* (CV) |
NEXIUM
40 mg |
NEXIUM
20 mg |
| AUC (μmol•h/L) |
12.6 (42%) |
4.2 (59%) |
| Cmax (μmol/L) |
4.7 (37%) |
2.1 (45%) |
| Tmax (h) |
1.6 |
1.6 |
| t½(h) |
1.5 |
1.2 |
| *Values represent the geometric mean, except the T max,
which is the arithmetic mean ; CV = Coefficient of variation |
Distribution
Esomeprazole is 97% bound to plasma proteins. Plasma protein
binding is constant over the concentration range of 2 to 20 μ mol/L.
The apparent volume of distribution at steady state in healthy volunteers is
approximately 16 L.
Metabolism
Esomeprazole is extensively metabolized in the liver by the
cytochrome P450 (CYP) enzyme system. The metabolites of esomeprazole lack antisecretory
activity. The major part of esomeprazole's metabolism is dependent upon the hydroxy
and desmethyl metabolites. The remaining amount is dependent on CYP 3A4 which
forms the sulphone metabolite. CYP 2C19 isoenzyme exhibits polymorphism in the
metabolism of esomeprazole, since some 3% of Caucasians and 15 to 20% of Asians
lack CYP 2C19 and are termed Poor Metabolizers. At steady state, the ratio of
AUC in Poor Metabolizers to AUC in the rest of the population (Extensive
Metabolizers) is approximately 2.
Following administration of equimolar doses, the S- and R-isomers
are metabolized differently by the liver, resulting in higher plasma levels of
the S- than of the R-isomer.
Excretion
The plasma elimination half-life of esomeprazole is
approximately 1 to 1.5 hours. Less than 1% of parent drug is excreted in the
urine. Approximately 80% of an oral dose of esomeprazole is excreted as
inactive metabolites in the urine, and the remainder is found as inactive
metabolites in the feces.
Pharmacokinetics: Combination Therapy with Antimicrobials
Esomeprazole magnesium 40 mg once daily was given in
combination with clarithromycin 500 mg twice daily and amoxicillin 1000 mg
twice daily for 7 days to 17 healthy male and female subjects. The mean steady
state AUC and C max of esomeprazole increased by 70% and 18%, respectively
during triple combination therapy compared to treatment with esomeprazole
alone. The observed increase in esomeprazole exposure during coadministration
with clarithromycin and amoxicillin is not expected to produce significant
safety concerns.
The pharmacokinetic parameters for clarithromycin and
amoxicillin were similar during triple combination therapy and administration
of each drug alone. However, the mean AUC and Cmax for 14-hydroxyclarithromycin
increased by 19% and 22%, respectively, during triple combination therapy
compared to treatment with clarithromycin alone. This increase in exposure to
14-hydroxyclarithromycin is not considered to be clinically significant.
Special Populations
Geriatric
The AUC and C max values were slightly higher (25% and 18%,
respectively) in the elderly as compared to younger subjects at steady state.
Dosage adjustment based on age is not necessary.
Pediatric
1 to 11 Years of Age
The pharmacokinetics of esomeprazole were studied in
pediatric patients with GERD aged 1 to 11 years. Following once daily dosing
for 5 days, the total exposure (AUC) for the 10 mg dose in patients aged 6 to
11 years was similar to that seen with the 20 mg dose in adults and adolescents
aged 12 to 17 years. The total exposure for the 10 mg dose in patients aged 1
to 5 years was approximately 30% higher than the 10 mg dose in patients aged 6
to 11 years. The total exposure for the 20 mg dose in patients aged 6 to 11
years was higher than that observed with the 20 mg dose in 12 to 17 year-olds
and adults, but lower than that observed with the 40 mg dose in 12 to 17
year-olds and adults.
Table 5 : Summary of PK Parameters in 1 to 11 Year Olds with
GERD Following 5 Days of Once- Daily Oral Esomeprazole Treatment
| Parameter |
1 to 5 Year Olds |
6 to 11Year Olds |
| 10 mg (N=8) |
10 mg (N=7) |
20 mg (N=6) |
| AUC (μmol*h/L)* |
4.83 |
3.70 |
6.28 |
| Cmax (μmol/L)* |
2.98 |
1.77 |
3.73 |
| tmax (h)† |
1.44 |
1.79 |
1.75 |
| t½λz (h)* |
0.74 |
0.88 |
0.73 |
| Cl/F (L/h)* |
5.99 |
7.84 |
9.22 |
| *Geometric mean; †arithmetic mean |
12 to 17 Years of Age
The pharmacokinetics of NEXIUM were studied in 28 adolescent
patients with GERD aged 12 to 17 years inclusive, in a single center study.
Patients were randomized to receive NEXIUM 20 mg or 40 mg once daily for 8
days. Mean Cmax and AUC values of esomeprazole were not affected by body weight
or age; and more than dose-proportional increases in mean Cmax and AUC values
were observed between the two dose groups in the study. Overall, NEXIUM
pharmacokinetics in adolescent patients aged 12 to 17 years were similar to
those observed in adult patients with symptomatic GERD.
Table 6 : Comparison of PK Parameters in 12 to 17 Year Olds
with GERD and Adults with Symptomatic GERD Following the Repeated Daily Oral
Dose Administration of Esomeprazole*
| Parameter |
12 to 17 Year Olds (N=28) |
Adults (N=36) |
| 20 mg |
40 mg |
20 mg |
40 mg |
| AUC(μmol*h/L) |
3.65 |
13.86 |
4.2 |
12.6 |
| Cmax(μmol/L) |
1.45 |
5.13 |
2.1 |
4.7 |
| tmax (h) |
2.00 |
1.75 |
1.6 |
1.6 |
| t½λz (h) |
0.82 |
1.22 |
1.2 |
1.5 |
Data presented are geometric means for AUC, C max and t˝
λz, and median value for tmax.
*Duration of treatment for 12 to 17 year olds and adults were 8 days and
5 days, respectively. Data were obtained from two independent studies. |
Gender
The AUC and Cmax values were slightly higher (13%) in
females than in males at steady state. Dosage adjustment based on gender is not
necessary.
Hepatic Insufficiency
The steady state pharmacokinetics of esomeprazole obtained
after administration of 40 mg once daily to 4 patients each with mild (Child
Pugh A), moderate (Child Pugh Class B), and severe (Child Pugh Class C) liver
insufficiency were compared to those obtained in 36 male and female GERD
patients with normal liver function. In patients with mild and moderate hepatic
insufficiency, the AUCs were within the range that could be expected in
patients with normal liver function. In patients with severe hepatic
insufficiency the AUCs were 2 to 3 times higher than in the patients with
normal liver function. No dosage adjustment is recommended for patients with
mild to moderate hepatic insufficiency (Child Pugh Classes A and B). However,
in patients with severe hepatic insufficiency (Child Pugh Class C) a dose of 20
mg once daily should not be exceeded [ see DOSAGE AND ADMINISTRATION].
Renal Insufficiency
The pharmacokinetics of NEXIUM in patients with renal
impairment are not expected to be altered relative to healthy volunteers as
less than 1% of esomeprazole is excreted unchanged in urine.
Other pharmacokinetic observations
Coadministration of oral contraceptives, diazepam,
phenytoin, or quinidine did not seem to change the pharmacokinetic profile of
esomeprazole.
Studies evaluating concomitant administration of
esomeprazole and either naproxen (nonselective NSAID) or rofecoxib (COX-2
selective NSAID) did not identify any clinically relevant changes in the
pharmacokinetic profiles of esomeprazole or these NSAIDs.
Microbiology
NEXIUM, amoxicillin, and clarithromycin triple therapy has
been shown to be active against most strains of Helicobacter pylori (H.
pylori) in vitro and in clinical infections as described in the Clinical
Studies (14) and Indications and Usage (1) sections.
Helicobacter pylori: Susceptibility testing of H. pylori isolates
was performed for amoxicillin and clarithromycin using agar dilution methodology,
and minimum inhibitory concentrations (MICs) were determined.
Pretreatment Resistance: Clarithromycin pretreatment resistance
rate (MIC ≥ 1 mcg/mL) to H. pylori was 15% (66/445) at baseline in
all treatment groups combined. A total of > 99% (394/395) of patients had
H. pylori isolates that were considered to be susceptible (MIC ≤ 0.25
mcg/mL) to amoxicillin at baseline. One patient had a baseline H. pylori isolate
with an amoxicillin MIC = 0.5 mcg/mL.
Clarithromycin Susceptibility Test Results and Clinical/Bacteriologic
Outcomes: The baseline H. pylori clarithromycin susceptibility
results and the H. pylori eradication results at the Day 38 visit are
shown in the table below:
Table 7 : Clarithromycin Susceptibility Test Results and
Clinical/Bacteriological Outcomes a for Triple Therapy - (Esomeprazole magnesium
40 mg once daily/amoxicillin1000 mg twice daily/clarithromycin 500 mg twice
daily for 10 days)
| Clarithromycin Pretreatment Results |
H. pylori negative (Eradicated) |
H.pylori positive (Not Eradicated)
Post-treatment susceptibility results |
| |
|
Sb |
Ib |
Rb |
No MIC |
| Susceptibleb |
182 |
162 |
4 |
0 |
2 |
14 |
| Intermediateb |
1 |
1 |
0 |
0 |
0 |
0 |
| Resistantb |
29 |
13 |
1 |
0 |
13 |
2 |
a Includes only patients with
pretreatment and post-treatment clarithromycin susceptibility test results
b Susceptible (S) MIC ≤ 0.25 mcg/mL, Intermediate (I) MIC
= 0.5 mcg/mL, Resistant (R) MIC ≥ 1.0 mcg/mL |
Patients not eradicated of H. pylori following NEXIUM/amoxicillin/clarithromycin
triple therapy will likely have clarithromycin resistant H. pylori isolates.
Therefore, clarithromycin susceptibility testing should be done, when possible.
Patients with clarithromycin resistant H. pylori should not be re-treated
with a clarithromycin-containing regimen.
Amoxicillin Susceptibility Test Results and Clinical/Bacteriological
Outcomes: In the NEXIUM/amoxicillin/clarithromycin clinical trials,
83% (176/212) of the patients in the NEXIUM/amoxicillin/clarithromycin treatment
group who had pretreatment amoxicillin susceptible MICs ( ≤ 0.25 mcg/mL)
were eradicated of H. pylori, and 17% (36/212) were not eradicated of H. pylori.
Of the 36 patients who were not eradicated of H. pylori on triple therapy,
16 had no post-treatment susceptibility test results and 20 had post-treatment
H. pylori isolates with amoxicillin susceptible MICs. Fifteen of the
patients who were not eradicated of H. pylori on triple therapy also
had post-treatment H. pylori isolates with clarithromycin resistant MICs.
There were no patients with H. pylori isolates who developed treatment
emergent resistance to amoxicillin.
Susceptibility Test for Helicobacter pylori: The reference methodology
for susceptibility testing of H. pylori is agar dilution MICs. One to
three microliters of an inoculum equivalent to a No. 2 McFarland standard (1
x 107 - 1 x 108 CFU/mL for H. pylori) are inoculated directly onto freshly prepared
antimicrobial containing Mueller-Hinton agar plates with 5% aged defibrinated
sheep blood ( > 2 weeks old). The agar dilution plates are incubated at 35°C
in a microaerobic environment produced by a gas generating system suitable for
Campylobacter. After 3 days of incubation, the MICs are recorded as the
lowest concentration of antimicrobial agent required to inhibit growth of the
organism. The clarithromycin and amoxicillin MIC values should be interpreted
according to the following criteria:
Table 8
| Clarithromycin MIC (mcg/mL)a |
Interpretation |
| ≤ 0.25 |
Susceptible(S) |
| 0.5 |
Intermediate(I) |
| ≥ 1.0 |
Resistant(R) |
| Amoxicillin MIC (mcg/mL) a,b |
Interpretation |
| ≤ 0.25 |
Susceptible(S) |
a These are breakpoints for the agar dilution
methodology and they should not be used to interpret results obtained
using alternative methods.
b There were not enough organisms with MICs > 0.25 mcg/mL
to determine a resistance breakpoint. |
Standardized susceptibility test procedures require the use of laboratory control
microorganisms to control the technical aspects of the laboratory procedures.
Standard clarithromycin and amoxicillin powders should provide the following
MIC values:
Table 9
| Microorganism |
Antimicrobial Agent |
MIC (mcg/mL)a |
| H. pylori ATCC 43504 |
Clarithromycin |
0.016 – 0.12 (mcg/mL) |
| H. pylori ATCC 43504 |
Amoxicillin |
0.016 – 0.12 (mcg/mL) |
| a These are quality control ranges for the agar
dilution methodology and they should not be used to control test results
obtained using alternative methods. |
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.
Animal Toxicology and/or Pharmacology
Reproductive Toxicology Studies
Reproductive studies have been performed in rats at oral
doses up to 280 mg/kg/day (about 57 times the human dose on a body surface area
basis) and in rabbits at oral doses up to 86 mg/kg/day (about 35 times the
human dose on a body surface area basis) and have revealed no evidence of
impaired fertility or harm to the fetus due to esomeprazole.
Reproductive studies conducted with omeprazole in rats at
oral doses up to 138 mg/kg/day (about 56 times the human dose on a body surface
area basis) and in rabbits at doses up to 69 mg/kg/day (about 56 times the
human dose on a body surface area basis) 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 5.5 to 56 times the human dose on a body surface area
basis) 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 5.6 to 56
times the human dose on a body surface area basis).
Clinical Studies
Healing of Erosive Esophagitis
The healing rates of NEXIUM 40 mg, NEXIUM 20 mg, and
omeprazole 20 mg (the approved dose for this indication) were evaluated in
patients with endoscopically diagnosed erosive esophagitis in four multicenter,
double-blind, randomized studies. The healing rates at Weeks 4 and 8 were
evaluated and are shown in the table below:
Table 10 : Erosive Esophagitis Healing Rate (Life-Table Analysis)
| Study |
No. of Patients |
Treatment Groups |
Week 4 |
Week 8 |
Significance Level* |
| 1 |
588 |
NEXIUM 20 mg |
68.7% |
90.6% |
N.S. |
| 588 |
Omeprazole 20 mg |
69.5% |
88.3% |
|
| 2 |
654 |
NEXIUM 40 mg |
75.9% |
94.1% |
p < 0.001 |
| 656 |
NEXIUM 20 mg |
70.5% |
89.9% |
p < 0.05 |
| 650 |
Omeprazole 20 mg |
64.7% |
86.9% |
|
| 3 |
576 |
NEXIUM 40 mg |
71.5% |
92.2% |
N.S. |
| 572 |
Omeprazole 20 mg |
68.6% |
89.8% |
|
| 4 |
1216 |
NEXIUM 40 mg |
81.7% |
93.7% |
p < 0.001 |
| 1209 |
Omeprazole 20 mg |
68.7% |
84.2% |
|
*log-rank test vs. omeprazole 20 mg
N.S. = not significant (p > 0.05). |
In these same studies of patients with erosive esophagitis, sustained heartburn resolution and time to sustained heartburn resolution were evaluated and are
shown in the table below:
Table 11 : Sustained Resolution‡ of Heartburn (Erosive Esophagitis
Patients)
| |
|
|
Cumulative Percent# with Sustained Resolution |
|
| Study |
No. of Patients |
Treatment Groups |
Day 14 |
Day 28 |
Significance Level * |
| 1 |
573 |
NEXIUM 20 mg |
64.3% |
72.7% |
N.S. |
| 555 |
Omeprazole 20 mg |
64.1% |
70.9% |
|
| 2 |
621 |
NEXIUM 40 mg |
64.8% |
74.2% |
p < 0.001 |
| 620 |
NEXIUM 20 mg |
62.9% |
70.1% |
N.S. |
| 626 |
Omeprazole 20 mg |
56.5% |
66.6% |
|
| 3 |
568 |
NEXIUM 40 mg |
65.4% |
73.9% |
N.S. |
| 551 |
Omeprazole 20 mg |
65.5% |
73.1% |
|
| 4 |
1187 |
NEXIUM 40 mg |
67.6% |
75.1% |
p < 0.001 |
| 1188 |
Omeprazole 20 mg |
62.5% |
70.8% |
|
‡Defined as 7 consecutive days with no heartburn
reported in daily patient diary.
#Defined as the cumulative proportion of patients who have reached the
start of sustained resolution
*log-rank test vs. omeprazole 20 mg
N.S. = not significant (p > 0.05). |
In these four studies, the range of median days to the start of sustained resolution
(defined as 7 consecutive days with no heartburn) was 5 days for NEXIUM 40 mg,
7 to 8 days for NEXIUM 20 mg and 7 to 9 days for omeprazole 20 mg.
There are no comparisons of 40 mg of NEXIUM with 40 mg of
omeprazole in clinical trials assessing either healing or symptomatic relief of
erosive esophagitis.
Long-Term Maintenance of Healing of Erosive Esophagitis
Two multicenter, randomized, double-blind placebo-controlled
4-arm trials were conducted in patients with endoscopically confirmed, healed erosive
esophagitis to evaluate NEXIUM 40 mg (n=174), 20 mg (n=180), 10 mg (n=168) or
placebo (n=171) once daily over six months of treatment.
No additional clinical benefit was seen with NEXIUM 40 mg
over NEXIUM 20 mg.
The percentages of patients that maintained healing of
erosive esophagitis at the various time points are shown in the figures below:
Figure 2 : Maintenance of Healing Rates by Month (Study
177)
Figure 3 : Maintenance of Healing Rates by Month (Study 178)
Patients remained in remission significantly longer and the
number of recurrences of erosive esophagitis was significantly less in patients
treated with NEXIUM compared to placebo.
In both studies, the proportion of patients on NEXIUM who
remained in remission and were free of heartburn and other GERD symptoms was
well differentiated from placebo.
In a third multicenter open label study of 808 patients
treated for 12 months with NEXIUM 40 mg, the percentage of patients that
maintained healing of erosive esophagitis was 93.7% for six months and 89.4%
for one year.
Symptomatic Gastroesophageal Reflux Disease (GERD)
Two multicenter, randomized, double-blind,
placebo-controlled studies were conducted in a total of 717 patients comparing
four weeks of treatment with NEXIUM 20 mg or 40 mg once daily versus placebo
for resolution of GERD symptoms. Patients had ≥ 6-month history of
heartburn episodes, no erosive esophagitis by endoscopy, and heartburn on at
least four of the seven days immediately preceding randomization.
The percentage of patients that were symptom-free of
heartburn was significantly higher in the NEXIUM groups compared to placebo at
all follow-up visits (Weeks 1, 2, and 4).
No additional clinical benefit was seen with NEXIUM 40 mg
over NEXIUM 20 mg.
The percent of patients symptom-free of heartburn by day are
shown in the figures below:
Figure 4 : Percent of Patients Symptom-Free of Heartburn
by Day (Study 225)
Figure 5 : Percent of Patients Symptom-Free of Heartburn
by Day (Study 226)
In three European symptomatic GERD trials, NEXIUM 20 mg and
40 mg and omeprazole 20 mg were evaluated. No significant treatment related
differences were seen.
Pediatric Gastroesophageal Reflux Disease (GERD)
1 to 11 Years of Age
In a multicenter, parallel-group study, 109 pediatric
patients with a history of endoscopically- proven GERD (1 to 11 years of age;
53 female; 89 Caucasian, 19 Black, 1 Other) were treated with NEXIUM once daily
for up to 8 weeks to evaluate safety and tolerability. Dosing by patient weight
was as follows:
weight < 20 kg: once daily treatment with NEXIUM 5 mg or
10 mg
weight ≥ 20 kg: once daily treatment with NEXIUM 10 mg
or 20 mg
Patients were endoscopically characterized as to the
presence or absence of erosive esophagitis.
Of the 109 patients, 53 had erosive esophagitis at baseline
(51 had mild, 1 moderate, and 1 severe esophagitis). Although most of the
patients who had a follow up endoscopy at the end of 8 weeks of treatment
healed, spontaneous healing cannot be ruled out because these patients had low
grade erosive esophagitis prior to treatment, and the trial did not include a concomitant
control.
12 to 17 Years of Age
In a multicenter, randomized, double-blind, parallel-group
study, 149 adolescent patients (12 to 17 years of age; 89 female; 124
Caucasian, 15 Black, 10 Other) with clinically diagnosed GERD were treated with
either NEXIUM 20 mg or NEXIUM 40 mg once daily for up to 8 weeks to evaluate
safety and tolerability. Patients were not endoscopically characterized as to the
presence or absence of erosive esophagitis.
Risk Reduction of NSAID-Associated Gastric Ulcer
Two multicenter, double-blind, placebo-controlled studies
were conducted in patients at risk of developing gastric and/or duodenal ulcers
associated with continuous use of non-selective and COX-2 selective NSAIDs. A
total of 1429 patients were randomized across the 2 studies. Patients ranged in
age from 19 to 89 (median age 66.0 years) with 70.7% female, 29.3% male, 82.9%
Caucasian, 5.5% Black, 3.7% Asian, and 8.0% Others. At baseline, the patients in
these studies were endoscopically confirmed not to have ulcers but were
determined to be at risk for ulcer occurrence due to their age ( ≥ 60
years) and/or history of a documented gastric or duodenal ulcer within the past
5 years. Patients receiving NSAIDs and treated with NEXIUM 20 mg or 40 mg
once-a-day experienced significant reduction in gastric ulcer occurrences
relative to placebo treatment at 26 weeks. No additional benefit was seen with NEXIUM
40 mg over NEXIUM 20 mg. These studies did not demonstrate significant
reduction in the development of NSAID-associated duodenal ulcer due to the low
incidence.
Table 12 : Cumulative percentage of patients without gastric
ulcers at 26 weeks:
| Study |
No. of Patients |
Treatment Group |
% of Patients Remaining Gastric Ulcer Free1 |
| 1 |
191 |
NEXIUM 20 mg |
95.4 |
| 194 |
NEXIUM 40 mg |
96.7 |
| 184 |
Placebo |
88.2 |
| 2 |
267 |
NEXIUM 20 mg |
94.7 |
| 271 |
NEXIUM 40 mg |
95.3 |
| 257 |
Placebo |
83.3 |
| 1 %= Life Table Estimate. Significant difference
from placebo (p < 0.01). |
Helicobacter pylori (H. pylori) Eradication in Patients with Duodenal Ulcer
Disease
Triple Therapy (NEXIUM/amoxicillin/clarithromycin): Two multicenter,
randomized, double-blind studies were conducted using a 10 day treatment regimen.
The first study (191) compared NEXIUM 40 mg once daily in combination with amoxicillin
1000 mg twice daily and clarithromycin 500 mg twice daily to NEXIUM 40 mg once
daily plus clarithromycin 500 mg twice daily. The second study (193) compared
NEXIUM 40 mg once daily in combination with amoxicillin 1000 mg twice daily
and clarithromycin 500 mg twice daily to NEXIUM 40 mg once daily. H. pylori
eradication rates, defined as at least two negative tests and no positive
tests from CLOtest ®, histology and/or culture, at 4 weeks post-therapy
were significantly higher in the NEXIUM plus amoxicillin and clarithromycin
group than in the NEXIUM plus clarithromycin or NEXIUM alone group. The results
are shown in the following table:
Table 13 : H. pylori Eradication Rates at 4 Weeks
after 10 Day Treatment Regimen % of Patients Cured [95% Confidence Interval]
(Number of Patients)
| Study |
Treatment Group |
Per-Protocol† |
Intent-to-Treat ‡ |
| 191 |
NEXIUM plus amoxicillin and clarithromycin |
84%* |
77%* |
| [78, 89] |
[71, 82] |
| (n=196) |
(n=233) |
| NEXIUM plus clarithromycin |
55% |
52% |
| [48, 62] |
[45, 59] |
| (n=187) |
(n=215) |
| 193 |
NEXIUM plus amoxicillin and clarithromycin |
85%** |
78%** |
| [74, 93] |
[67, 87] |
| (n=67) |
(n=74) |
| NEXIUM |
5% |
4% |
| [0, 23] |
[0, 21] |
| (n=22) |
(n=24) |
† Patients were included in the analysis
if they had H. pylori infection documented at baseline, had at
least one endoscopically verified duodenal ulcer ≥ 0.5 cm in diameter
at baseline or had a documented history of duodenal ulcer disease within
the past 5 years, and were not protocol violators. Patients who dropped
out of the study due to an adverse reaction related to the study drug
were included in the analysis as not H. pylori eradicated.
‡ Patients were included in the analysis if they had documented
H. pylori infection at baseline, had at least one documented duodenal
ulcer at baseline, or had a documented history of duodenal ulcer disease,
and took at least one dose of study medication. All dropouts were included
as not H. pylori eradicated.
*p < 0.05 compared to NEXIUM plus clarithromycin
**p < 0.05 compared to NEXIUM alone |
The percentage of patients with a healed baseline duodenal ulcer by 4 weeks
after the 10 day treatment regimen in the NEXIUM plus amoxicillin and clarithromycin
group was 75% (n=156) and 57% (n=60) respectively, in the 191 and 193 studies
(per-protocol analysis).
Pathological Hypersecretory Conditions Including Zollinger-Ellison Syndrome
In a multicenter, open-label dose-escalation study of 21
patients (15 males and 6 females, 18 Caucasian and 3 Black, mean age of 55.5
years) with pathological hypersecretory conditions, such as Zollinger-Ellison
Syndrome, NEXIUM significantly inhibited gastric acid secretion. Initial dose
was 40 mg twice daily in 19/21 patients and 80 mg twice daily in 2/21 patients.
Total daily doses ranging from 80 mg to 240 mg for 12 months maintained gastric
acid output below the target levels of 10 mEq/h in patients without prior
gastric acid-reducing surgery and below 5 mEq/hr in patients with prior gastric
acid-reducing surgery. At the Month 12 final visit, 18/20 (90%) patients had
Basal Acid Output (BAO) under satisfactory control (median BAO = 0.17 mmol/hr).
Of the 18 patients evaluated with a starting dose of 40 mg twice daily, 13
(72%) had their BAO controlled with the original dosing regimen at the final visit.
Table 14 : Adequate Acid Suppression at Final Visit by Dose
Regimen
| NEXIUM dose at the Month 12 visit |
BAO under adequate control at the Month 12
visit (N=20)* |
| 40 mg twice daily |
13/15 |
| 80 mg twice daily |
4/4 |
| 80 mg three times daily |
1/1 |
| *One patient was not evaluated. |
REFERENCES
1. National Committee for Clinical Laboratory Standards. Methods
for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically.
Fifth Edition: Approved Standard NCCLS Document M7-A5, Vol. 20, no. 2, NCCLS,
Wayne, PA, January 2000.
Last updated on RxList: 10/27/2009