COLD AGGLUTININ DISEASE | ANX1502 Passes Phase 1 Trial, Proving Safe for Healthy Volunteers

Twice-daily dosing of ANX1502, an experimental oral therapy by Annexon Biosciences for autoimmune conditions like cold agglutinin disease (CAD), achieved desired blood levels in healthy volunteers participating in a Phase 1 clinical trial.
Administered orally as a liquid suspension, ANX1502 demonstrated good tolerability, with no serious side effects reported. The drug’s pharmacokinetics also supported twice-daily dosing for a future proof-of-concept study.
“We are thrilled to reach this significant milestone in ANX1502’s clinical development – a first-of-its-kind small molecule complement inhibitor with the potential to impact a variety of autoimmune conditions,” said Ted Yednock, PhD, Annexon’s Chief Innovation Officer, in a company press release. “Based on these findings, we anticipate advancing a tablet formulation of ANX1502 into a proof-of-concept study for CAD patients.”
CAD is a rare form of autoimmune haemolytic anemia in which the immune system mistakenly targets and destroys the body’s red blood cells. When the blood of affected individuals is exposed to cold temperatures (32º to 50º F), specific proteins, known as IgM antibodies, that typically target bacteria, attach to the red blood cells and cause them to clump together (agglutination). This process ultimately results in the premature destruction of red blood cells (haemolysis), leading to anaemia and its related signs and symptoms.
The Phase 1 trial (NCT05521269) was designed to evaluate ANX1502’s safety, tolerability, pharmacokinetics, and pharmacodynamics (effects on the body) in up to 84 healthy adults enrolled at a single site in the Netherlands.
Results showed that ANX1502 reached the desired levels in the blood in both the single and multiple ascending dose groups. Moreover, measures of pharmacokinetics varied in a dose-dependent manner.
“We are highly encouraged by the results of our Phase 1 study, which demonstrated that ANX1502 was well-tolerated and achieved target drug levels, along with a positive impact on a key biomarker in healthy volunteers,” said Yednock.
Upon completing the proof-of-concept study in individuals with CAD, Annexon intends to further evaluate ANX1502’s efficacy in severe complement-mediated autoimmune diseases. The ultimate aim is to offer patients an effective treatment featuring convenient dosing for long-term use.