Comparative efficacy of esomeprazole and omeprazole: Racemate to single enantiomer switch

Abstract

BackgroundBoth omeprazole and its S enantiomer (esomeprazole) have been available and used to treat symptoms of gastroesophageal reflux disease (GERD) and conditions associated with excessive stomach acid secretion for more than a decade. Controversy exists over improved efficacy of S enantiomer (esomeprazole) over parent racemate (omeprazole). However, a comparison of the clinical outcomes of these products may reveal the rationale for switching from the racemate to single enantiomer. Since enantiomers of omeprazole are equipotent, we compared the outcomes of equal doses of each product to see if both actually differ in their efficacy’s or the reported superiority of S enantiomer is just a dose effect.MethodsA web search was carried out for randomized controlled trials with head-to-head comparisons of omeprazole and S-omeprazole. The data were abstracted and after calculating theodd ratios (OR) for the outcomes reported in each study, the combined overall odd ratios (OR’) were estimated. The random effect inverse variance method with omeprazole as the reference (OR” = 1) was used.ResultsOut of 1171 studies, 14 were deemed eligible. There was no significant difference in the therapeutic success between omeprazole and S-omeprazole as a part of triple therapy for the treatment of H. pylori in both intention-to-treat (OR’, 1.06; CI, 0.83, 1.36; p = 0.63) as well as per-protocol analysis (OR’, 1.07; CI, 0.84, 1.36; p = 0.57). For the treatment of gastro-oesophageal reflux disease, S-omeprazole was significantly but marginally superior to the racemate (OR’, 1.18; CI, 1.01, 1.38; p = 0.04). The two products were equipotent in all metrics used to assess intragastric pH except for the % patients maintaining a 24 h gastric pH above 4 (1.57; CI, 1.04, 2.381; p = 0.03).ConclusionThe therapeutic benefit of chiral switch of omeprazole is questionable considering the substantially greater economic burden involved.

Pharmacological Effects and Toxicogenetic Impacts of Omeprazole: Genomic Instability and Cancer

“…In clinical studies, there is evidence of the OME gastroprotective function at doses of 5 to 40 mg/kg by mechanisms associated with interaction with H2 receptors [57], pH control [58], inhibition of CYP2C19 enzymes [42,43], and histamine blockade [59]. OME in in vivo studies increased prostaglandins and sulfhydryl compounds [60], increased expression of BAX and caspases [61], and AhR and CYP1A expression [41].…”

Effects of Plasma Albumin on the Pharmacokinetics of Esomeprazole in ICU Patients

“…However, pharmacokinetic characteristics of them were difference. Many randomized controlled trials (RCTs) and cohort and case-control studies show that esomeprazole has a higher bioavailability, better clinical efficacy, and treatment capacity for acid-related diseases than omeprazole [4–6]. Depending on the superior acid control ability and good tolerance, esomeprazole has been widely used to patients with acid-related disease including of stress-ulcer prophylaxis in China.…”

Interconnection of sulfides and sulfoxides in medicinal chemistry

“…A randomized controlled trial with head to head comparison between omeprazole and esomeprazole found esomeprazole slightly superior for treatment of gastroesophageal reflux disease. Yet, the same study reported no significant difference for Helicobacter pylori treatment outcome . Esomeprazole (20 mg, for 5 days) showed 90% suppression of gastric acidity, which was only marginally higher compared to 79% suppression achieved by identical dosage of omeprazole .…”