Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Patients Who are Complement Inhibitor-Naïve

The data described below reflect exposure of 204 patients with PNH who were complement inhibitor-naïve and who were randomized in COMMODORE 2 to receive PIASKY (n = 135) or eculizumab (n = 69) at the recommended dosing regimen for 24 weeks [see Clinical Studies (14)].

Serious adverse reactions occurred in 6% of patients receiving PIASKY in the COMMODORE 2 study, including epistaxis and pneumonia, which occurred in 2 patients each, and infusion related reaction, pyelonephritis, COVID-19, and hypovolemic shock which were reported in 1 patient each.

Table 4 lists adverse reactions that occurred at a rate of 5% or more among patients randomized to PIASKY treatment for 24 weeks in the COMMODORE 2 study. The most common adverse reactions (≥10%) in patients treated with PIASKY were infusion related reaction, respiratory tract infection, and viral infection.

Patients Previously Treated with a Complement C5 Inhibitor

The data described below reflect exposure of 86 patients with PNH who received PIASKY (n=44) or eculizumab (n=42) at the recommended dosing regimen for 24 weeks in COMMODORE 1, an open-label, active-controlled, multicenter study conducted in patients switching from eculizumab. The median age was 47 years (range: 21 to 85); 52% were female, and race included White (73%), Asian (19%), unknown (5%), and Black/African-American (3%). The population ethnicities were 17% Hispanic or Latino and 76% not Hispanic or Latino.

Serious adverse reactions in COMMODORE 1 were reported in 3 patients (7%) with PNH receiving PIASKY. Serious adverse reactions included pneumonia, nasopharyngitis, and urinary tract infection, which occurred in 1 patient each.

Table 5 lists adverse reactions that occurred at a rate of 5% or more among patients randomized to PIASKY treatment for 24 weeks in the COMMODORE 1 study. The most common adverse reactions (≥10%) in patients treated with PIASKY were viral infections, respiratory tract infection, Type III hypersensitivity reaction, infusion-related reaction, peripheral edema, and headache.

Type III Hypersensitivity Reactions Related to Drug-Target-Drug Complexes [see Warnings and Precautions (5.3), and Drug Interactions (7)].

Across the COMMODORE 1 and 2 studies, 39 out of 201 (19.4%) patients who switched from eculizumab or ravulizumab to PIASKY experienced a Type III hypersensitivity reaction (reported as Type III immune complex mediated reaction). A total of 6 patients had switched two times and of the 6 patients, 2 patients experienced a second episode of Type III hypersensitivity reaction after discontinuing PIASKY and switching to ravulizumab. One of these patients developed Grade 3 axonal neuropathy and a Type III hypersensitivity reaction could not be excluded and the other developed Grade 2 arthralgia and myalgia. These two events remained unresolved at the last follow up visit of the clinical studies (the duration of the events until last follow-up was 313 days for the event of Grade 3 axonal neuropathy and 142 days for the event of Grade 2 arthralgia and myalgia, respectively). Two additional patients who experienced Grade 3 rash and Grade 3 arthralgia, respectively, had unresolved Type III hypersensitivity reaction at the last follow-up visit.

The median time to onset of Type III hypersensitivity reaction in patients who switched treatment from eculizumab or ravulizumab to PIASKY was 1.6 weeks (range: 0.7 – 4.4 weeks) and the median duration of Type III hypersensitivity reactions was 1.9 weeks (range 0.4 – 34.1 weeks). The majority of events were Grade 1-2. Grade 3 Type III hypersensitivity reaction occurred in 8% of patients who switched from eculizumab or ravulizumab to PIASKY. Out of 42 Type III hypersensitivity reactions, 37 (88%) resolved, including 1 (2.4%) that resolved with PIASKY discontinuation, 2 (4.8%) that resolved with PIASKY interruption and 34 (81%) that resolved without discontinuation, interruption, or dose change in PIASKY therapy.

Axonal Neuropathy

In COMMODORE 1 and 2, Grade 3 distal axonal demyelinating polyneuropathy and Grade 3 axonal neuropathy were reported, each in 1 patient who switched from another C5 inhibitor to PIASKY or from PIASKY to another C5 inhibitor. The Grade 3 distal axonal demyelinating polyneuropathy occurred 11 weeks after a patient switched from eculizumab to PIASKY (with first dose of PIASKY received 12 days after the last dose of eculizumab treatment) and was preceded by a bacterial respiratory tract infection. The Grade 3 axonal neuropathy occurred in a patient who had switched to ravulizumab treatment after 6 weeks of treatment with PIASKY, and previously received ravulizumab treatment prior to switching to treatment with PIASKY [see Warnings and Precautions (5.3)]. Events associated with the axonal neuropathy included COVID-19, sepsis and administration of a fluoroquinolone. In both cases of axonal neuropathy, a Type III hypersensitivity reaction as a cause of, or contributor to, the axonal neuropathy could not be excluded. Both cases of axonal neuropathy remained unresolved at the last follow up visit of the clinical studies.

Pediatric Population with PNH Treated with PIASKY

Twelve pediatric patients with PNH (9 treatment-naïve patients and 3 patients who switched from another C5 inhibitor) were treated with PIASKY in COMMODORE 1 (n=2), COMMODORE 2 (n=7), and in a single-arm trial [(COMMODORE 3 (n=3)]. The safety profile of PIASKY appeared comparable between adult and pediatric patients, but conclusions are limited by the small number of pediatric patients.