An Open-label Extension Trial to Evaluate the Long-term Safety of KVD900 (Sebetralstat) for On-Demand Treatment of Angioedema Attacks in Adolescent and Adult Patients With Hereditary Angioedema (HAE)

Exclusion Criteria

• •1. Discontinued from the KVD900-301 trial for reasons of noncompliance, withdrawal of consent, or safety.
• •2. Presence of any safety concerns that would preclude participation in the open-label trial as determined by the investigator.
• •3. Any concomitant diagnosis of another form of chronic angioedema, such as acquired C1 inhibitor deficiency, HAE with normal C1-INH (previously known as HAE type III), idiopathic angioedema, or angioedema associated with urticaria.
• •4. A clinically significant history of poor response to bradykinin receptor 2 (BR2) blocker, C1-INH therapy, or plasma kallikrein inhibitor therapy for the management of HAE, in the opinion of the Investigator.
• •5. Use of attenuated androgens other than danazol (e.g., stanozolol, oxandrolone, methyltestosterone, testosterone), or anti-fibrinolytics (e.g., tranexamicacid) within 28 days prior to the Enrollment Visit.
• •6. Use of Angiotensin-converting enzyme (ACE) inhibitors within 7 days prior to the Enrollment Visit.
• •7. Any estrogen-containing medications with systemic absorption (such as oral contraceptives including ethinylestradiol or hormonal replacement therapy) within 7 days prior to the Enrollment Visit.
• •8. Inadequate organ function, including but not limited to:
• •1. Alanine aminotransferase (ALT) \>2x Upper Limit Normal (ULN)
• •2. Aspartate aminotransferase (AST) \>2x ULN
• •3. Bilirubin direct \>1.25x ULN
• •4. International Normalized Ratio (INR) \>1.2
• •5. Clinically significant hepatic impairment defined as a Child-Pugh B or C
• •9. Any clinically significant comorbidity or systemic dysfunction, which in the opinion of the Investigator, would jeopardize the safety of the patient by participating in the trial.
• •10. History of substance abuse or dependence that would interfere with the completion of the trial, as determined by the Investigator.
• •11. Known hypersensitivity to KVD900 or to any of the excipients.
• •12. Participation in any gene therapy treatment or trial for HAE.
• •13. Participation in any interventional investigational clinical trial, including an investigational COVID-19 vaccine trial, within 4 weeks of the last dosing of investigational drug prior to the Enrollment Visit.
• •14. Any pregnant or breastfeeding patient.