The study consisted of a 60-day screening period to assess eligibility and conduct vaccinations if required (for all patients not previously vaccinated at least 2 weeks prior to first dosing or if prior vaccination cannot be confirmed) and 4 treatment periods as follows. During the treatment period 1 (Days 1 to 29), all patients received infusions of LFG316 every 14 days. Following assessment of efficacy (hemolytic activity by serum LDH) at the end of treatment period 1, patients entered the optional 48-week treatment period 2 and continued LFG316 infusions every 14 days. At the end of treatment period 2, LFG316-responsive patients (assessed based on the investigator's judgment) were allowed to enter an additional extension period of up to 260 weeks (treatment period 3) in which they continued to receive LFG316 every 14 days. Period 4, which allowed patients to switch to LNP023, lasted approximately 21 weeks. During the first 4 weeks, patients continued to receive LFG316 in addition to oral administration of LNP023. After 4 weeks, patients discontinued LFG316 and continued with LNP023 monotherapy for approximately 16 weeks (+/- 28 days). Patients who participated in period 4 could join the long-term extension study CLNP023C12001B (NCT04747613) as soon as their eligibility was confirmed and study CLNP023C12001B was open to receive patients. There was no LNP023 treatment gap between the studies.
As per strategic decision, further development of LFG316 was terminated in favor of LNP023, Novartis offered patients enrolled in study CLFG316X2201 a conversion from LFG316 to LNP023, aiming to provide uninterrupted treatment for these PNH patients. The CLFG316X2201 trial was not a terminated study.