Omeprazole is a mixture of two mirror image molecules. One of the two versions is the active and the other isn't (for 97% of the population). When the patent wa

Omeprazole is a mixture of two mirror image molecules. One of the two versions is the active and the other isn't (for 97% of the population). When the patent was running out on omeprazole AstraZeneca patented esomeprazole, which is just the active isomer. In order to show improvement over omeprazole they did clinical trials that used a higher effective dose of esomeprazole than omeprazole. The FDA, for reasons unknown, let them get away with this fraud and approved the drug. The government has spent literally billions of dollars buying esomeprazole when a double dose of omeprazole is the same damn thing for 97% of the population. I caveated my original statement ("something close to") because there might be some role for esomeprazole as a second line drug for the 3% of the population that is sensitive to the other isomer, but even there a perfectly fine alternative would just be a lower dose of omeprazole. Nexium is 18th on the list of drugs by global sales in 2014. These are not small potatoes.