Rallybio Corporation announced positive findings from new biomarker analyses and manufacturing process enhancements for RLYB116, its investigational once-weekly, subcutaneous C5 inhibitor. These advancements support the potential of RLYB116 as a best-in-class treatment for complement-mediated diseases, leading to plans for a confirmatory clinical pharmacokinetic/pharmacodynamic (PK/PD) study in the second quarter of 2025.
Following the completion of a Phase 1 single- and multiple-ascending dose (SAD/MAD) study in late 2023, new biomarker characterization analyses revealed that the initial assay used to measure free C5 overestimated levels by approximately ten-fold. This suggests RLYB116 achieved significantly greater complement inhibition than initially reported in the Phase 1 study.
Concurrent with these findings, manufacturing process enhancements completed in the third quarter of 2024 are expected to further improve RLYB116’s tolerability. Enhanced analytical techniques, including mass spectrometry, have led to further purification of the drug substance. This improved purity is anticipated to yield a more favorable tolerability profile at doses equal to or greater than those evaluated in the Phase 1 MAD study.
The upcoming confirmatory PK/PD study, scheduled for the second quarter of 2025, aims to demonstrate both improved tolerability and complete, sustained complement inhibition. This single-blind, multiple ascending dose study will involve two cohorts of eight participants each, evaluating weekly doses of 150 mg and 225 mg, respectively, over a 4-week treatment period followed by a 10-week follow-up period.
RLYB116, designed for the treatment of complement-mediated diseases, is administered subcutaneously once weekly in small volumes. The previous Phase 1 SAD/MAD study, conducted in healthy participants, explored the safety, tolerability, pharmacokinetics, and pharmacodynamics of RLYB116. This study, completed in the fourth quarter of 2023, employed an adaptive single-blind design with a 4-week treatment duration and a 10-week follow-up. Four cohorts were included, evaluating various dosing regimens, including weekly dosing of 100 mg, three initial doses of 100 mg followed by weekly dosing, weekly 150 mg dosing reduced to 125 mg weekly, and twice-weekly 75 mg escalating to twice-weekly 100 mg.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
