Kidney Week

Abstract: FR-PO0838

Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of MIL116, a Novel "Sweeper" Anti-A Proliferation-Inducing Ligand Monoclonal Antibody in Healthy Volunteers: Preliminary Phase 1 Results

Session Information

• Glomerular Diseases: Practice and New Concepts Shaping Modern Care
  October 23, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics

Authors

• Jinjin, Liang, Beijing Mabworks Biotech Co Ltd, Beijing, China

Liang Jinjin, MD

• Liang, Yan, Peking University First Hospital, Beijing, China

Yan Liang, MS, RPh

• Liu, Xifang, Beijing Mabworks Biotech Co Ltd, Beijing, China

Xifang Liu, PharmD

• Wei, Min, Beijing Mabworks Biotech Co Ltd, Beijing, China

Min Wei

• Li, Jiangmei, Beijing Mabworks Biotech Co Ltd, Beijing, China

Jiangmei Li, PhD

• Wang, Xia, Beijing Mabworks Biotech Co Ltd, Beijing, China

Xia Wang, PharmD

• Liu, Sijun, Beijing Mabworks Biotech Co Ltd, Beijing, China

Sijun Liu

• Luo, Stacey, Climb Bio, Inc., Wellesley, Massachusetts, United States

Stacey Luo, PharmD, RPh

• Charles, Edgar D., Climb Bio, Inc., Wellesley, Massachusetts, United States

Edgar D. Charles, MD

• Li, Feng, Beijing Mabworks Biotech Co Ltd, Beijing, China

Feng Li, PhD

• Zhao, Xia, Peking University First Hospital, Beijing, China

Xia Zhao, MS, RPh

Background

MIL116 (CLYM116) is an investigational, novel ‘sweeper’ anti– A PRoliferation–Inducing Ligand (APRIL) mAb engineered with both pH–dependent antigen–binding to enhance APRIL degradation and antibody recycling, and Fc mutations to extend half–life (t_1/2) and diminish its effector function. APRIL is a key driver of galactose-deficient IgA1 (Gd–IgA1) in IgA nephropathy (IgAN). This first-in-human Phase 1 portion of a Phase 1/2 study (NCT07375758) is designed to evaluate the safety, tolerability, pharmacokinetic (PK), pharmacodynamic (PD), and immunogenicity of subcutaneous (SC) MIL116 in healthy volunteers in China and support dose selection for IgAN participants.

Methods

This is a randomized, double-blind, placebo–controlled, single–ascending dose (SAD) study enrolling adult healthy volunteers. Eligible participants receive SC MIL116 across 5 dose cohorts, with safety and tolerability assessed up to 24 weeks. Primary endpoint: safety (adverse events [AEs], laboratory parameters, etc.). Secondary endpoints: PK (AUC, C_max, t_1/2, etc.), PD (serum IgA, Gd–IgA1, APRIL, etc.), and immunogenicity.

Results

As of May 9, 2026, 20 healthy volunteers from 4 cohorts were evaluable. MIL116 was well tolerated, with no dose–limiting toxicities (DLTs), serious adverse events (SAEs), or discontinuations. PK data confirmed a prolonged t_1/2 for MIL116 in humans, supporting the potential for extended dosing intervals. Dose–dependent reductions in serum IgA and Gd–IgA1 were observed in the available data from the first 2 dose cohorts, with nadir and recovery kinetics consistent with the pharmacological mechanism of APRIL inhibition. Planned PK/PD modeling will inform dose selection. The study results were similarly confirmed in an ex–China Phase 1 study (NCT07248865) involving healthy participants. Initial safety, PK, and PD data from the Phase 1 portion of this study will be presented at the meeting.

Conclusion

Preliminary data from this Phase 1 study of MIL116 in healthy participants indicate favorable tolerability. The PK profile suggests potential for extended dosing intervals. PK/PD modeling based on Phase 1 data will support dose selection for the Phase 2 portion. These results support further clinical development of MIL116 as a potentially disease–modifying therapy for IgAN.