The expanded access program allows people to gain access to an unlicensed treatment on compassionate grounds. Lanadelumab, also known as TAK-743, is a medicine to help prevent angioedema attacks. This expanded access program enables these participants with a high unmet medical need to continue receiving lanadelumab during the interim period between completion of either the SHP643-301 (NCT04070326; SPRING study) or the TAK-743-3001 (NCT04444895) study and potential licensure of lanadelumab for the respective age group and/or treatment.

Inclusion Criteria:

TAK-743-6001 Study (Acute Attacks of HAE):

• Pediatric participants, 2 to <12 years of age, with HAE who completed the SHP643-301 (SPRING) study and are deriving continued clinical benefit from lanadelumab treatment will be invited to take part in this program
• Participants have no suitable alternative treatment options and cannot enter a lanadelumab clinical trial
• Participant has a parent(s)/legal guardian who is informed of the nature of the expanded access program and can provide written informed consent for the child to participate (with assent from child when appropriate) prior to treatment
• Participants does not have any of the following liver function test abnormalities : alanine aminotransferase (ALT) greater than (>)3x upper limit of normal (ULN), or aspartate aminotransferase (AST) >3x ULN, or total bilirubin >2x ULN (unless the bilirubin elevation is a result of Gilbert's syndrome)
• Participant does not have any condition that in the opinion of the Investigator may compromise their safety
• Participant does not have a known hypersensitivity to lanadelumab or its components
• Participant (greater than or equal to >or=6 years) and/or caregiver is willing to self-administer lanadelumab at home and has received documented training on self-administration during the SHP643-301 (SPRING) Study

For Female participants of childbearing potential only:

• Participant has agreed to be abstinent or agreed to comply with the applicable contraceptive requirements of this protocol for the duration of the expanded access program and for 70 days after completion
• Participant is not pregnant or breast-feeding Note: Participants who do not satisfy the above criteria will be excluded.

TAK-743-5012 Study (Acute Attacks of Non-histaminergic Angioedema With Normal C1-Inhibitor (C1-INH)):

• Participant has completed the treatment period of the TAK-743-3001 study (all Visit 14 assessments have been completed).
• Participant is demonstrating continued benefit from lanadelumab treatment.
• Participant and/or a parent(s)/legal guardian is informed of the nature of the expanded access program and can provide written informed consent for themselves or the child to participate (with assent from child when appropriate) prior to treatment).
• Participant does not have any condition including lab test that in the opinion of the Investigator may compromise their safety.
• Participant does not have a known hypersensitivity to lanadelumab or its components.
• Participant and/or caregiver is willing to self-administer lanadelumab at home and has received documented training on self-administration during the Study TAK-743-3001 OR the participant and/or caregiver is willing to self-administer lanadelumab at home and will receive training at the first two dose administrations in accordance with protocol.

Female Participants of childbearing potential only:

• Participant has agreed to be abstinent or agreed to comply with the applicable contraceptive requirements of this protocol for the duration of the expanded access program and for 70 days after completion of the last dose.
• Participant is not pregnant or breast-feeding.

Male Participants only:

• Participant has agreed to comply with the applicable contraceptive requirements of this protocol for the duration of the expanded access program and for 70 days following the last dose of lanadelumab
• Participant has agreed to not donate sperm during the course of the program and for 70 days following the last dose of lanadelumab.