Long-term preventive KN057 treatment for Hemophilia A and B

An Open-label Study to Evaluate the Safety of KN057 Long-term Prophylaxis in Patients With Hemophilia A or Hemophilia B With or Without Inhibitors

This trial will try long-term KN057 preventive treatment to see if it is safe and helps males aged 12–65 with Hemophilia A or B, with or without inhibitors.

Quick facts

• Phase: Phase 3
• Study type: Interventional
• Enrollment: 70 (estimated)
• Ages: 12 Years to 65 Years
• Sex: Male
• Sponsor: Suzhou Alphamab Co., Ltd. (Industry-sponsored)
• Drugs / interventions: Emicizumab
• Locations: 1 site (Tianjin, Tianjin Municipality)
• Trial ID: NCT07545395 on ClinicalTrials.gov

What this trial studies

This open-label, multicenter Phase 3 trial tests long-term prophylaxis with KN057 in males with Hemophilia A or B, including those with inhibitors, and compares pharmacokinetics between two manufacturing processes. In the PK part participants are randomized 1:1 to an old-process then new-process sequence or to continuous new-process KN057 for 52 weeks. A non-PK part enrolls participants non-randomly to receive new-process KN057 for 52 weeks. The trial prioritizes screening of participants who previously took part in KN057-A-301 or KN057-A-302.

Who should consider this trial

Good fit: Ideal candidates are males aged 12–65 years, weighing at least 30 kg with BMI under 28 kg/m2, who have severe or moderately severe Hemophilia A or B or documented inhibitors as defined in the protocol, with priority for prior KN057-A-301/302 participants.

Not a fit: Patients outside the age, weight, or BMI limits, females (not eligible), those with only mild hemophilia, or with contraindications to KN057 are unlikely to receive benefit from participation.

Why it matters

Potential benefit: If successful, KN057 prophylaxis could reduce bleeding episodes and improve long-term management for people with Hemophilia A or B, including some with inhibitors.

How similar studies have performed: Prophylactic factor-replacement approaches have a long track record of reducing bleeds, but direct comparisons of different manufacturing processes for the same product are less commonly reported.

Eligibility criteria

Inclusion Criteria:

1. Male, 12 to 65 years old at the time of signing informed consent, body weight ≥30 kg and BMI \<28 kg/m\^2 at screening.
2. For participates with inhibitors: Tested positive for high-titer FVIII or FIX inhibitors (≥ 5 BU/mL) at screening; or tested positive for low-titer FVIII or FIX inhibitors (0.6 BU/mL or upper limit of normal \[ULN\] \< inhibitor titer \< 5 BU/mL) at screening, with ongoing treatment using bypassing agents (rFVIIa or PCC).

   For participates without inhibitors: Severe and moderately severe hemophilia A or hemophilia B (FVIII or FIX activity level ≤2%); FVIII or FIX inhibitor test is negative (\<0.6 BU/ml) or lower than the lower limit of laboratory normal values during the screening period; There is no history of FVIII or FIX inhibitors in the past, or there has been an inhibitor, but the inhibitor has turned negative for at least 5 years before screening and has not reappeared (no positive inhibitor was detected); Use coagulation factor replacement therapy for no less than 100 exposure days before screening.
3. Participates with inhibitors agree to avoid using PCC for treatment when breakthrough bleeding occurred. Participates without inhibitors agree to be treated with standard half-life coagulation factors (FVIII or FIX) in the event of breakthrough bleeding.

Exclusion Criteria:

1. Have serious or poorly controlled chronic diseases or obvious systemic diseases.
2. Have a history of thromboembolic disease, or currently have symptoms or signs related to thromboembolic disease or being treated with thrombolytic/antithrombotic therapy.
3. Have high-risk factors for thrombosis: such as atrial fibrillation, atherosclerotic diseases of important arteries, ischemic disease of important organs, vascular occlusive disease, autoimmune diseases with a high risk of thrombosis, or indwelling central venous catheter.
4. Known or suspected hypersensitivity to any constituent of the trial product or related products.
5. Have undergone major surgery (as determined by the investigator) within 3 months before screening, or have elective surgery planned during the study.
6. Used Emicizumab treatment within 6 months before screening.
7. Have received any gene therapy for hemophilia in the past.
8. Other factors that the investigator deems inappropriate for participating in this trial, such as the presence of concomitant diseases, treatment or examination abnormalities that affect the subject's safety during the trial or affect the interpretation of trial results.

Where this trial is running

Tianjin, Tianjin Municipality

• Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences — Tianjin, Tianjin Municipality, China (Recruiting)

Study contacts

• Principal investigator: Renchi Yang, Doctor — Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences
• Study coordinator: Yanrong Dong, Master

Conditions Hemophilia A or B