Principia Confirms Human CNS Exposure and Good Tolerability of Oral BTK Inhibitor PRN2246

The double blind, placebo controlled, single and multiple ascending dose trial is evaluating the pharmacokinetics, BTK receptor occupancy, safety and tolerability of PRN2246 given orally to over 70 healthy volunteers. PRN2246 has been well-tolerated in the study, and achieved high and sustained peripheral BTK occupancy at clinically relevant dose levels studied. Importantly, in a dedicated arm of the trial, exposure of PRN2246 was confirmed in cerebral spinal fluid (CSF), highlighting the potential for PRN2246 to impact B-cell driven inflammation in both the periphery and central nervous system (CNS).

Upon Principia’s completion of early development work, Sanofi plans to develop this experimental oral therapy for the treatment of multiple sclerosis (MS) and, potentially, other CNS diseases that are driven by autoantibodies and inflammation. Potential for direct activity in the CNS may allow targeting of disease mechanisms that are normally shielded by the blood-brain barrier.

"Confirmation that PRN2246 crosses the blood-brain barrier in humans and achieves therapeutic levels in the CSF is an important milestone for this program and our collaboration with Sanofi," said Martin Babler, Chief Executive Officer of Principia Biopharma. "We now look forward to evaluating the potential additional benefit of modulating B-cells directly in both the periphery and the CNS in MS patients."

About Principia Biopharma

Principia Biopharma Inc., a private, clinical-stage biopharmaceutical company, has created a revolutionary new way to design and develop oral small molecule therapies that are more potent, selective, durable and safer than currently available drugs. The Company has utilized its proprietary Tailored Covalency® technology to develop a portfolio of drug candidates that exhibit antibody-like specificity to benefit patients with autoimmune and inflammatory diseases and cancer. PRN1008, a reversible covalent BTK inhibitor, is currently being evaluated in a Phase 2 clinical trial in patients with pemphigus, an orphan autoimmune disease, and in a Phase 2 clinical trial in patients with immune thrombocytopenic purpura, an orphan hematological disease. PRN1371, a covalent FGFR1-4 inhibitor, is currently being evaluated in a Phase 1 clinical trial in cancer patients with various solid tumors. PRN2246, a low dose covalent BTK inhibitor which crosses the blood-brain barrier, recently has completed dosing in a Phase 1 clinical trial in healthy volunteers. For more information, please visit the Company's website at www.principiabio.com.

View source version on businesswire.com: https://www.businesswire.com/news/home/20180726005830/en/