A Study of Ravulizumab (ALXN1210) in Children and Adolescents With Paroxysmal Nocturnal Hemoglobinuria

Inclusion Criteria:

1. Participants from birth up to <18 years of age and weighing ≥ 5 kilograms at the timeof consent.
2. PNH diagnosis confirmed by documented high-sensitivity flow cytometry.
3. Presence of 1 or more of the following PNH-related signs or symptoms within 3 monthsof Screening: fatigue, hemoglobinuria, abdominal pain, shortness of breath (dyspnea),anemia, history of a major adverse vascular event (including thrombosis), dysphagia,or erectile dysfunction; or history of packed red blood cell transfusion due to PNH.
4. Lactate dehydrogenase (LDH) level ≥ 1.5 × upper limit of normal (ULN) for participantsnot being treated with eculizumab at screening and LDH level ≤ 1.5 × ULN forparticipants taking eculizumab.
5. Documented meningococcal vaccination not more than 3 years prior to dosing, andvaccination against Streptococcus pneumoniae and Haemophilus influenzae.
6. Female participants of childbearing potential must use highly effective contraceptionstarting at screening and continuing until at least 8 months after the last dose ofravulizumab.

Exclusion Criteria:

1. History of bone marrow transplantation.
2. History of or ongoing major cardiac, pulmonary, renal, endocrine, or hepatic diseasethat, in the opinion of the investigator or sponsor, would preclude participation.
3. Unstable medical conditions (for example, myocardial ischemia, active gastrointestinalbleed, severe congestive heart failure, anticipated need for major surgery within 6months of randomization, coexisting chronic anemia unrelated to PNH).
4. Females who are pregnant or breastfeeding or who have a positive pregnancy test atscreening or Day 1.
5. Participation in another interventional clinical study or use of any experimentaltherapy within 30 days before initiation of study drug on Day 1 in this study orwithin 5 half-lives of that investigational product, whichever is greater.