This study will assess the safety,efficacy,pharmacokinetics and pharmacodynamics of multiple-dose of STSP-0601 at two dose levels for the treatment of bleeding episodes in hemophilia A or B patients without inhibitor.

Inclusion Criteria:

• 18 ≤age≤70 years of age,male;
• Hemophilia A or B patients;
• A bleeding event requiring treatment occurred (Only applicable to the on-demand treatment stage);
• Factor VIII or IX level <2%, inhibitor titer < 0.6 BU;
• There were at least 2 bleeding events that requiring treatment occurred in the past 6 months before screening (Only the second stage is applicable);
• Establish proper venous access;
• Agree to use adequate contraception to avoid pregnancy;
• Provide signed informed consent.

Exclusion Criteria:

• Have any coagulation disorder other than hemophilia;
• Plan to receive prophylactic treatment of coagulation factor during the trail;
• 4 weeks before screening, receive prophylactic treatment of amesetuzumab or plan to receive prophylactic treatment of amesetuzumab during the trial;
• Patients received anticoagulant or antifibrinolytic therapy 7 days before enrollment or plan to receive these drugs during the trial;
• Patients received anticoagulation therapy (such as coagulation factor replacement therapy, prothrombin complex, plasma, etc.) 7 days before enrollment;
• Have a history of arterial and/or venous thrombotic events;
• Platelet <100×109/L;
• Hemoglobin<90g/L;
• Severe liver or kidney disease;
• Severe bleeding event occurred within 4 weeks before enrollment;
• Accepted major operation or blood transfusion within 4 weeks before enrollment;
• HIV positive;
• Have a known allergy to STSP-0601;
• Participate in other clinical research within 4 weeks before enrollment(except for participating in prothrombin complex, FVII, FVIIa, FVIII, FIX trails);
• Patients not suitable for the trail according to the judgment of the investigators.