Most of the gastroprotective drugs which had been marketed in Japan were considered to have insufficient rationale for use as ulcer treatments. Such drugs may have a crucial role in maintaining mucosal integrity by the mechanisms other than inhibition of acid secretion. We re-evaluated the effect of gastroprotective drugs on gastric ulcer healing using current ICH E9 guidelines. We collected reports of pivotal trials on healing rate of gastric ulcer with 9 kinds of gastroprotective drugs submitted in New Drug Applications. In the comparative trial of cetraxate vs. placebo, the healing rate of gastric ulcer at 8-week endoscopy in the cetraxate was significantly higher than that in the placebo groups (88.6% and 62.2%, p = 0.0062). Non-inferiority to cetraxate was confirmed for 8 kinds of gastroprotective drugs. In conclusion, the superiority of cetraxate over placebo and non-inferiority to cetraxate for 7 drugs was established in the respect of effect on ulcer healing.