The investigators propose a study to evaluate the safety, local tolerability, convenience, and efficacy of self-administered Icatibant for the treatment of acute attacks of hereditary angioedema. The investigators believe that self administration with Icatibant for treatment of an acute attack of angioedema will not change the time to complete or near complete resolution of symptoms compared to treatment with Icatibant in a medical facility.

Inclusion Criteria:

1. Males and females at least 18 years of age at the time of informed consent

2. Documented diagnosis of hereditary angioedema Type I or II based on ALL of the following criteria:

   • Family and/or medical history
   • Characteristic attack manifestations, recurrent attacks
   • Historical low C4, normal C1q and either low C1-INH or low C1INH function

3. Women of childbearing potential must use consistently and correctly a highly effective, adequate method of birth control (failure rate less than 1% per year), sexual abstinence or have a vasectomised partner during the duration of the study. Hormonal contraception can be continued if verified by a physician that it doesn't affect the course of hereditary angioedema attacks.

4. Mental and physical condition allowing patients to complete baseline assessment, to self-administer Icatibant and to follow other study procedures.

5. Ability to provide signed written informed consent after all aspects of the study have been explained and discussed with the patient.

Exclusion Criteria:

1. Participation in a clinical therapeutic trial of another investigational medicinal product within the past month (except a previous Icatibant study).
2. Diagnosis of angioedema other than Type I or Type II hereditary angioedema.
3. Evidence of symptomatic coronary artery disease based on medical history, in particular, unstable angina pectoris or severe coronary heart disease.
4. Congestive heart failure (NYHA Class 3 and 4).
5. Stroke within the past 6 months.
6. Treatment with angiotensin converting enzyme inhibitor.
7. Pregnancy and/or breast-feeding.
8. In the opinion of the investigator: mental condition rendering the patient unable to understand the nature, scope and possible consequences of the study.
9. In the opinion of the investigator: unlikely to comply with the protocol, for example, uncooperative attitude, inability to return for follow-up visits, or unlikely to complete the study for any reason.
10. In the opinion of the investigator: inability to complete the patient diary, manage study medication or self-administration of an injection.

The data is under review for publication but individual data will likely not be available

Adverse events were recorded throughout the study.

Adverse events were assessed out of total attacks, not total participants. There were 78 HAE attacks with data collected and recorded on adverse events.

All adverse events were recorded and assessed out of total attacks, not total participants. There were 78 HAE attacks; 4 adverse events were identified.