AC0058 – BTK Inhibitor

AC0058 is a small molecule that potently, selectively, and irreversibly inhibits Bruton’s tyrosine kinase (BTK) phosphorylation and downstream signaling. In preclinical studies, AC0058 inhibited inflammatory cytokine production in monocytes and activation of lymphocytes (predominantly B cells).

Preclinical studies demonstrated that AC0058 has the potential to disrupt signaling mediated by tyrosine kinases and may be useful for controlling excessive or aberrant T and B cell activation in autoimmune diseases.

Consequently, AC0058 is being investigated as a targeted therapy for systemic lupus erythematosus (SLE), an autoimmune disease characterized by over-active B cells. It is anticipated that this drug can address the unmet needs of many patients with SLE, for whom there are currently no effective therapies.

>90% BTK occupancy achieved for all doses evaluated in Phase I MAD study.

ACEA has successfully completed a Phase I clinical trial of AC0058 in 56 healthy volunteers in the U.S. Our compound was found to be safe and well tolerated at all tested doses (50-600 mg total daily dose). Based on the encouraging safety data, robust pharmacodynamic (>90% BTK occupancy), and dose-dependent pharmacokinetic findings, ACEA has initiated a Phase Ib study of AC0058 in SLE patients.

For more information about our completed and ongoing clinical trials, please visit

AC0058 is an investigational drug candidate and has not yet been approved for use by the U.S. Food and Drug Administration (FDA), China Food and Drug Administration (CFDA) or other regulatory authorities.