Long-Term, Open-label Study of Oral Deucrictibant Extended-Release Tablet for Prophylaxis Against Angioedema Attacks in Adolescents and Adults With HAE

Inclusion Criteria:

1. Provision of written informed consent/assent.

2. Male or female, aged ≥12 years at the time of providing written informedconsent/assent.

3. Diagnosis of hereditary angioedema (HAE)

4. For participants that did not participate in a previous deucrictibant prophylacticstudy: history of at least 1 attack in the last 3 consecutive months prior toScreening

5. Reliable access and ability to use standard of care on-demand treatments toeffectively manage acute HAE attacks.

6. Willing and able to adhere to all protocol requirements, including eDiary and ePROdata recording.

7. Female participants of childbearing must agree to the protocol specified pregnancytesting and contraception methods.

Exclusion Criteria:

1. Any diagnosis of angioedema other than HAE

2. Participation in a clinical study with any other investigational drug within thelast 30 days or within 5 half-lives of the investigational drug at ICF signature (whichever is longer)

3. Prior gene therapy for any indication at any time

4. Participants who discontinued from previous studies with deucrictibant prophylacticand/or on-demand treatment due to safety reasons or compliance issues that, in theopinion of the Investigator, would interfere with the participant's safety orcompliance to participate in the study

5. Exposure to ACE inhibitors or any estrogen-containing medications with systemicabsorption within 4 weeks of Screening

6. Use of prophylactic treatment for HAE within 2 weeks of Screening for C1INH, oralkallikrein inhibitors, or anti-fibrinolytics; within 4 weeks of Screening forattenuated androgens; within 5 half-lives of Screening for monoclonal antibodies, orwithin 7 days of Screening for short-term prophylaxis

7. Any females who are pregnant, plan to become pregnant, or are currentlybreast-feeding

8. Abnormal hepatic function

9. Moderate or severe renal impairment

10. Any clinically significant comorbidity or systemic dysfunction that would interferewith the participant's safety or ability to participate in the study.

11. History of alcohol or drug abuse within the previous year, or current evidence ofsubstance dependence or abuse

12. Use of medications that are moderate and strong inhibitors or strong inducers ofCYP3A4 within the last 30 days or within 5 half-lives (whichever is longer) of thetime of randomization

13. Known hypersensitivity to deucrictibant or any of the excipients of the study drug