ARQ 531 is an investigational BTK inhibitor. We are currently in the process of conducting additional efficacy, toxicology and pharmacology studies that, if positive, would allow us to file an Investigational New Drug (IND) application in 2017.
ARQ 531 is a reversible and orally bioavailable compound that potently inhibits the wild type and mutant (C481S) forms of BTK. Potent tumor growth inhibition has been observed in a TMD8 xenograft model as well as potent inhibition of p-BTK and its downstream signaling. ARQ 531 has also demonstrated potent signs of activity in additional preclinical models.
Patients with tumors harboring the BTK C481S mutation could benefit from being targeted by ARQ 531, a potent inhibitor of that mutation.
Preliminary studies suggest an opportunity for clinical development of ARQ 531 in ibrutinib resistant cancers.