TEAEs were defined as adverse events (AE) that occurred after dosing on Day 1 and up to 30 days after the last dose of study drug. A treatment-related TEAE was defined as a TEAE with a relationship to study drug of possible, probable, or definite. TEAEs were graded according to the Common Terminology Criteria for Adverse Events (v4.03) based on: Grade 1: Mild, Grade 2: Moderate, Grade 3: Severe, Grade 4: Life-threatening, Grade 5: Death related to AE.

The safety set consisted of all subjects who received at least 1 dose of study drug.

Serum chemistry assessments of LDH were made at the last measurement prior to the first dose of pegcetacoplan (baseline) and periodically throughout the treatment period.

The Intent-to-treat (ITT) set consisted of all subjects who received at least 1 dose of study drug.

Serum chemistry assessments of haptoglobin were made at the last measurement prior to the first dose of pegcetacoplan (baseline) and periodically throughout the treatment period.

The ITT set consisted of all subjects who received at least 1 dose of study drug.

Hematology assessments of Hb were made at the last measurement prior to the first dose of pegcetacoplan (baseline) and periodically throughout the treatment period.

The ITT set consisted of all subjects who received at least 1 dose of study drug.

The FACIT-Fatigue scale is a 13 item Likert scaled instrument where the subject was presented with 13 statements and asked to indicate their response as it applied to the past 7 days. The 5 possible responses were 'Not at all' (0), 'A little bit (1), 'Somewhat' (2), 'Quite a bit' (3) and 'Very much' (4). With 13 statements the total score had a range of 0 to 52. Higher score corresponds to a higher quality of life (QoL).

The ITT set consisted of all subjects who received at least 1 dose of study drug.

Hematology assessments of ARC were made at the last measurement prior to the first dose of pegcetacoplan (baseline) and periodically throughout the treatment period.

The ITT set consisted of all subjects who received at least 1 dose of study drug.

Serum chemistry assessments of total bilirubin were made at the last measurement prior to the first dose of pegcetacoplan (baseline) and periodically throughout the treatment period.

The ITT set consisted of all subjects who received at least 1 dose of study drug.

The number of on-study RBC transfusions was monitored throughout the treatment period.

The ITT set consisted of all subjects who received at least 1 dose of study drug.

The LASA consists of 3 items, where the respondents were asked to rate their perceived level of functioning. Specific domains included activity level, ability to carry out daily activities, and an item for overall QoL. Their level of functioning was reported on a 0 to 100 scale with 0 indicates "As low as could be" and 100 indicates "As high as could be". The combined score ranged from 0 to 300, with higher scores corresponding to a higher QoL.

The ITT set consisted of all subjects who received at least 1 dose of study drug.

Serum concentrations of pegcetacoplan at Day 365 are presented.

The Pharmacokinetic (PK) set consisted of all subjects in the safety set who had at least 1 quantifiable PK sample post dose PK measurement.

The AUCtotal of pegcetacoplan was estimated using a non-compartmental approach.

The PK set consisted of all subjects in the safety set who had at least 1 quantifiable PK sample post dose PK measurement.

The Ctrough,max,total of pegcetacoplan was estimated using a non-compartmental approach.

The PK set consisted of all subjects in the safety set who had at least 1 quantifiable PK sample post dose PK measurement.