A Study of Long-Term Safety and Efficacy of Lanadelumab for Prevention of Acute Attacks of Non-histaminergic Angioedema With Normal C1-Inhibitor

Inclusion Criteria:

• Males and females, 12 years of age and older diagnosed with non-histaminergic normalC1-INH angioedema at the time of enrollment into the antecedent Study SHP643-303 (NCT04206605).

• Participants must have completed the treatment period (through Visit 26/Day 182) ofStudy SHP643-303 (NCT04206605) without reporting a clinically significant TEAE thatwould preclude subsequent exposure to lanadelumab.

• Agree to adhere to the protocol-defined schedule of treatments, assessments, andprocedures.

• Males, or non-pregnant, non-lactating females who are of child-bearing potential andwho agree to be abstinent or agree to comply with the applicable contraceptiverequirements of this protocol for the duration of the study; or females ofnon-childbearing potential, defined as surgically sterile (status post hysterectomy,bilateral oophorectomy, or bilateral tubal ligation) or post-menopausal for at least 12 months.

• The participant (or the participant's parent/legal guardian, if applicable) hasprovided written informed consent approved by the institutional reviewboard/research ethics board/ethics committee (IRB/REB/EC) at any time prior to studystart. If the participant is a minor (i.e. lesser then (<) 18 years of age), have aparent/legal guardian who is informed of the nature of the study provide writteninformed consent (i.e. permission) for the minor to participate in the study beforeany study-specific procedures are performed. Assent will be obtained from minorparticipants.

Exclusion Criteria:

• Discontinued from Study SHP643-303 (NCT04206605) after enrollment but before Visit 26 for any reason.

• Presence of important safety concerns identified in Study SHP643-303 (NCT04206605)that would preclude participation in this study.

• Dosing with an investigational product (IP, not including IP defined in antecedentStudy SHP643-303 [NCT04206605]) or exposure to an investigational device within 4weeks prior to Day 0.

• Participants has a known hypersensitivity to the investigational product or itscomponents.

• Have any condition (surgical or medical) that, in the opinion of the investigator orsponsor, may compromise their safety or compliance, preclude the successful conductof the study, or interfere with interpretation of the results (e.g. significantpre-existing illness or other major comorbidities that the investigator considersmay confound the interpretation of study results).