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Prilosec

Clinical Pharmacology
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Clinical Pharmacology

The combination of omeprazole plus clarithromycin plus amoxicillin was effective in eradicating H. pylori .

Table 6 : Per-Protocol and Intent-to-Treat H. pylori Eradication Rates % of Patients Cured [95% Confidence Interval]

  PRILOSEC + amoxicillin
Per- Protocol †
+clarithromycin
Intent-to- Treat ‡
Clarithromycin
Per- Protocol †
+ amoxicillin
Intent- to-Treat ‡
Study 1 *77 [64, 86] *69 [57, 79] 43 [31, 56] 37 [27, 48]
(n = 64) (n = 80) (n = 67) (n = 84)
Study 2 *78 [67, 88] *73 [61, 82] 41 [29, 54] 36 [26, 47]
(n = 65) (n = 77) (n = 68) (n = 83)
Study 3 *90 [80, 96] *83 [74, 91] 33 [24, 44] 32 [23, 42]
(n = 69) (n = 84) (n = 93) (n = 99)
† 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.
‡ 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.
*(p < 0.05) versus clarithromycin plus amoxicillin.

Dual Therapy (PRILOSEC/clarithromycin)

Four randomized, double-blind, multi-center studies (4, 5, 6, and 7) evaluated PRILOSEC 40 mg once daily plus clarithromycin 500 mg three times daily for 14 days, followed by PRILOSEC 20 mg once daily, (Studies 4, 5, and 7) or by PRILOSEC 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 PRILOSEC 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 7 : H. pylori Eradication Rates (Per-Protocol Analysis at 4 to 6 Weeks) % of Patients Cured [95% Confidence Interval]

  PRILOSEC + Clarithromycin PRILOSEC Clarithromycin
U.S. Studies
Study 4 74 [60, 85] † ‡ 0 [0, 7] 31 [18, 47]
(n = 53) (n = 54) (n = 42)
Study 5 64 [51, 76] † ‡ 0 [0, 6] 39 [24, 55]
(n = 61) (n = 59) (n = 44)
Non U.S. Studies
Study 6 83 [71, 92] ‡ 1 [0, 7] N/A
(n = 60) (n = 74)  
Study 7 74 [64, 83] ‡ 1 [0, 6] N/A
(n = 86) (n = 90)  
Statistically significantly higher than clarithromycin monotherapy (p < 0.05)
Statistically significantly higher than omeprazole monotherapy (p < 0.05)

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 8: Duodenal Ulcer Recurrence Rates by H. pylori Eradication Status % of Patients with Ulcer Recurrence

  H. pylori eradicated# H. pylori not eradicated#
U.S. Studies †
6 months post-treatment
  Study 4 *35 60
(n = 49) (n = 88)
  Study 5 *8 60
(n = 53) (n = 106)
Non U.S. Studies ‡
6 months post-treatment
  Study 6 *5 46
(n = 43) (n = 78)
  Study 7 *6 43
(n = 53) (n = 107)
12 months post-treatment
  Study 6 *5 68
(n = 39) (n = 71)
#H. pylori eradication status assessed at same time point as ulcer recurrence
Combined results for PRILOSEC + clarithromycin, PRILOSEC, and clarithromycin treatment arms
Combined results for PRILOSEC + clarithromycin and PRILOSEC treatment arms
*(p≤0.01) versus proportion with duodenal ulcer recurrence who were not H. pylori eradicated

Gastric Ulcer

In a U.S. multicenter, double-blind, study of omeprazole 40 mg once daily, 20 mg once daily, and placebo in 520 patients with endoscopically diagnosed gastric ulcer, the following results were obtained.

Treatment of Gastric Ulcer % of Patients Healed (All Patients Treated)

  PRILOSEC
20 mg once daily
(n = 202)
PRILOSEC
40 mg. once daily
(n = 214)
Placebo
(n = 104)
Week 4 47.5** 55.6** 30.8
Week 8 74.8** 82.7**,+ 48.1
**(p < 0.01) PRILOSEC 40 mg or 20 mg versus placebo
+(p < 0.05) PRILOSEC 40 mg versus 20 mg

For the stratified groups of patients with ulcer size less than or equal to 1 cm, no difference in healing rates between 40 mg and 20 mg was detected at either 4 or 8 weeks. For patients with ulcer size greater than 1 cm, 40 mg was significantly more effective than 20 mg at 8 weeks.

In a foreign, multinational, double-blind study of 602 patients with endoscopically diagnosed gastric ulcer, omeprazole 40 mg once daily, 20 mg once daily, and ranitidine 150 mg twice a day were evaluated.

Treatment of Gastric Ulcer % of Patients Healed (All Patients Treated)

  PRILOSEC
20 mg once daily
(n = 200)
PRILOSEC
40 mg once daily
(n = 187)
Ranitidine
150 twice daily
(n = 199)
Week 4 63.5 78.1**,++ 56.3
Week 8 81.5 91.4**,++ 78.4
** (p < 0.01) PRILOSEC 40 mg versus ranitidine
++ (p < 0.01) PRILOSEC 40 mg versus 20 mg

Gastroesophageal Reflux Disease (GERD)

Symptomatic GERD

A placebo-controlled study was conducted in Scandinavia to compare the efficacy of omeprazole 20 mg or 10 mg once daily for up to 4 weeks in the treatment of heartburn and other symptoms in GERD patients without erosive esophagitis. Results are shown below.

% Successful Symptomatic Outcomea

  PRILOSEC
20 mg a.m.
PRILOSEC
10 mg a.m.
Placebo a.m.
All patients 46*,† 31† 13
(n = 205) (n = 199) (n = 105)
Patients with confirmed GERD 56*,† 36† 14
(n = 115) (n = 109) (n = 59)
aDefined as complete resolution of heartburn
*(p <0.005) versus 10 mg
† (p <0.005) versus placebo

Erosive Esophagitis

In a U.S. multicenter double-blind placebo controlled study of 20 mg or 40 mg of PRILOSEC Delayed-Release Capsules in patients with symptoms of GERD and endoscopically diagnosed erosive esophagitis of grade 2 or above, the percentage healing rates (per protocol) were as follows:

Week 20 mg PRILOSEC
(n = 83)
40 mg PRILOSEC
(n = 87)
Placebo
(n = 43)
4 39** 45** 7
8 74** 75** 14
** (p<0.01) PRILOSEC versus placebo.

In this study, the 40 mg dose was not superior to the 20 mg dose of PRILOSEC in the percentage healing rate. Other controlled clinical trials have also shown that PRILOSEC is effective in severe GERD. In comparisons with histamine H2-receptor antagonists in patients with erosive esophagitis, grade 2 or above, PRILOSEC in a dose of 20 mg was significantly more effective than the active controls. Complete daytime and nighttime heartburn relief occurred significantly faster (p < 0.01) in patients treated with PRILOSEC than in those taking placebo or histamine H2- receptor antagonists.

In this and five other controlled GERD studies, significantly more patients taking 20 mg omeprazole (84%) reported complete relief of GERD symptoms than patients receiving placebo (12%).

Long Term Maintenance Of Healing of Erosive Esophagitis

In a U.S. double-blind, randomized, multicenter, placebo controlled study, two dose regimens of PRILOSEC were studied in patients with endoscopically confirmed healed esophagitis. Results to determine maintenance of healing of erosive esophagitis are shown below.

  PRILOSEC
20 mg once daily
(n = 138)
Life Table Analysis
PRILOSEC
20 mg 3 days per week
(n = 137)
Placebo
(n = 131)
Percent in endoscopic remission at 6 months *70 34 11
*(p < 0.01) PRILOSEC 20 mg once daily versus PRILOSEC 20 mg 3 consecutive days per week or placebo.

In an international multicenter double-blind study, PRILOSEC 20 mg daily and 10 mg daily were compared with ranitidine 150 mg twice daily in patients with endoscopically confirmed healed esophagitis. The table below provides the results of this study for maintenance of healing of erosive esophagitis.

Life Table Analysis

  PRILOSEC
20 mg once daily
(n = 131)
PRILOSEC
10 mg once daily
(n = 133)
Ranitidine
150 mg twice daily
(n = 128)
Percent in endoscopic remission at 12 months *77 ‡ 58 46
*(p = 0.01) PRILOSEC 20 mg once daily. versus PRILOSEC 10 mg.once daily or Ranitidine.
(p = 0.03) PRILOSEC 10 mg.once daily. versus Ranitidine.

In patients who initially had grades 3 or 4 erosive esophagitis, for maintenance after healing 20 mg daily of PRILOSEC was effective, while 10 mg did not demonstrate effectiveness.

Pathological Hypersecretory Conditions

In open studies of 136 patients with pathological hypersecretory conditions, such as Zollinger-Ellison (ZE) syndrome with or without multiple endocrine adenomas, PRILOSEC Delayed-Release Capsules significantly inhibited gastric acid secretion and controlled associated symptoms of diarrhea, anorexia, and pain. Doses ranging from 20 mg every other day to 360 mg per day maintained basal acid secretion below 10 mEq/hr in patients without prior gastric surgery, and below 5 mEq/hr in patients with prior gastric surgery.

Initial doses were titrated to the individual patient need, and adjustments were necessary with time in some patients [See DOSAGE AND ADMINISTRATION] PRILOSEC was well tolerated at these high dose levels for prolonged periods (> 5 years in some patients). In most ZE patients, serum gastrin levels were not modified by PRILOSEC. However, in some patients serum gastrin increased to levels greater than those present prior to initiation of omeprazole therapy. At least 11 patients with ZE syndrome on long-term treatment with PRILOSEC developed gastric carcinoids. These findings are believed to be a manifestation of the underlying condition, which is known to be associated with such tumors, rather than the result of the administration of PRILOSEC. [See ADVERSE REACTIONS]

Pediatric GERD

Symptomatic GERD

The effectiveness of PRILOSEC for the treatment of nonerosive GERD in pediatric patients 1 to 16 years of age is based in part on data obtained from 125 pediatric patients in two uncontrolled Phase III studies. [See Use in Specific Populations]

The first study enrolled 12 pediatric patients 1 to 2 years of age with a history of clinically diagnosed GERD. Patients were administered a single dose of omeprazole (0.5 mg/kg, 1.0 mg/kg, or 1.5 mg/kg) for 8 weeks as an open capsule in 8.4% sodium bicarbonate solution. Seventy-five percent (9/12) of the patients had vomiting/ regurgitation episodes decreased from baseline by at least 50%.

The second study enrolled 113 pediatric patients 2 to 16 years of age with a history of symptoms suggestive of nonerosive 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.

Healing of Erosive Esophagitis

In an uncontrolled, open-label dose-titration study, healing of erosive esophagitis 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. Erosive esophagitis 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 Erosive Esophagitis

In an uncontrolled, open-label study of maintenance of healing of erosive esophagitis in 46 pediatric patients, 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. In addition, maintenance therapy in erosive esophagitis patients resulted in 63% of patients having no overall symptoms.

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.

Brand Name: Prilosec
Generic Name: Omeprazole
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