Multinational biopharmaceutical company UCB (Euronext Brussels:UCB) and US biotechnology company Biogen Inc. (NASDAQ:BIIB) on Thursday presented new data from the Phase 3 PHOENYCS GO study, highlighting significant clinical benefits of dapirolizumab pegol (DZP) in patients with moderate-to-severe systemic lupus erythematosus (SLE).

The drug met its primary endpoint, demonstrating improvement in disease activity at Week 48, as measured by the British Isles Lupus Assessment Group-based Composite Lupus Assessment.

Notably, patients receiving DZP in addition to standard of care experienced consistent improvements in fatigue, with meaningful gains observed in FACIT-Fatigue and FATIGUE-PRO measures. Enhanced outcomes were also reported across disease activity indicators such as Low Lupus Disease Activity State (LLDAS) and Definition of Remission in SLE (DORIS).

At Week 48, 40.9% of patients treated with dapirolizumab pegol achieved low disease activity, compared to 19.6% with standard of care alone. Disease remission was achieved by 19.2% of patients receiving the investigational drug, more than double the rate of the control group.

The safety profile was generally favourable and remained consistent with previous studies, with the DZP group showing a slightly higher rate of treatment-emergent adverse events (TEAEs) overall, but a lower rate of serious TEAEs than in the standard of care only group. Treatment discontinuation due to adverse events remained low across both arms.

A second Phase 3 study, PHOENYCS FLY, is ongoing to confirm these findings. Dapirolizumab pegol is not yet approved for use in SLE by any regulatory authority.