Peptic ulcer - tenatoprazole
Surgery was once the only treatment for serious peptic ulcers, but their treatment was revolutionised by the introduction first of the H2 antagonists and then the proton pump inhibitors. The hunt is still on for more effective drugs with longer durations of action, and one such product is Mitsubishi Pharma's tenatoprazole, which is being investigated to treat both peptic ulcers and gastro-oesophageal reflux disease (GERD).
In an open label randomised crossover trial in 18 healthy volunteers, subjects were given 20 or 40mg tenatoprazole or 40mg esomeprazole orally once a day for seven days.1 Median 24h gastric pH was 4.6 for those given the higher dose of the new drug, 4.0 for the lower dose and 4.2 with esomeprazole. The higher dose also gave longer night-time periods above 4.0 than the other two regimens.
Speed of onset has also been investigated. In an open label crossover trial in 24 healthy patients, the subjects were randomised to 40mg tenatoprazole or esomeprazole orally once a day for two days.2 In the first 24 hours, tenatoprazole gave a higher median gastric pH of 3.88, compared with 3.45 for esomeprazole. The difference was absent the second day, but the pH was significantly higher overnight on both nights for those subjects given tenatoprazole.
Its maintenance effects on gastric acid output have also been assessed.3 A total of 30 healthy volunteers were given 40mg tenatoprazole or esomeprazole once a day for seven days in a single blind randomised crossover trial.
The new drug was more effective at increasing gastric pH, with the results being better maintained. The effects in the two groups had equalised by five days after the final dose.