A prospective, multi-center, randomized controlled trial to evaluate safety and effectiveness of endoscopic hemostatic powder, 'Nexpowder' for hemostatic treatments of nonvariceal upper gastrointestinal bleeding.

This study is a prospective, multi-center, single blind (for patients), controlled investigation planned to evaluate safety and effectiveness of Nexpowder with 352 subject patients.

This investigational study is designed to compare effectiveness of using the standard-of-care hemostatic therapy only, versus the standard-of-care hemostatic therapy plus an additional hemostatic treatment using Nexpower for patients with nonvariceal, upper gastrointestinal bleeding from ulcers with high-risk stigmata (Forrest classification Ia, Ib, or IIa).

The primary end-points will be evaluated by assessing the rates of re-bleeding, which occur over three (3) days following initial hemostasis achieved with the standard-of-care hemostatic therapy.

Secondary end-points consist of evaluating three items: 1) Ease of use of Nexpowder applied for the test group after reaching initial hemostasis, 2) Nexpowder device malfunction and 3) safety follow-up to check occurrence of adverse event(s)/re-bleeding at 30-day (+5) time point.

Only the subjects whose initial hemostasis has been achieved will be registered for this investigation but those who initial hemostasis has failed to be reached with the standard-of-care therapie(s) shall not be registered for this investigation.

Inclusion Criteria:

• Adult male or female with age of older than 19 years.
• Patients showing non-variceal upper GI bleeding symptoms
• An endoscopic examination indicates that the patients's ulcer is categorized Class Ia, Ib, or IIa according to the Forrest Classifications.

Exclusion Criteria:

• Pregnant or breast-feeding patients