Supporting

CAMBRIDGE, Mass.–(BUSINESS WIRE)–Goldfinch Bio, a clinical stage biotechnology company focused on discovering and developing precision medicines for the treatment of kidney diseases, today announced for the first time results from its Phase 1 clinical trial evaluating GFB-887, a first-in-class highly potent and selective inhibitor of Transient Receptor Potential Canonical Channel 5 (TRPC5), in healthy volunteers. The data are being presented today at the virtual American Society of Nephrology (ASN) Kidney Week 2020 Annual Meeting.

Goldfinch Bio is developing GFB-887 as a precision medicine for patients with kidney diseases characterized by overactivation of the TRPC5-Rac1 pathway, including focal segmental glomerulosclerosis (FSGS) and diabetic nephropathy (DN). Overactivation of the TRPC5-Rac1 pathway leads to injury of podocytes, which are cells lining the kidney that, in their healthy state, prevent essential protein loss (proteinuria). Injury to podocytes causes podocyte loss, proteinuria and, eventually, kidney failure. TRPC5-Rac1 pathway overactivation is the key cause of disease in a substantial portion of FSGS and DN patients, and there are currently no approved drugs that specifically target the TRPC5-Rac1 pathway in these diseases.

“We are excited to share these first-in-human data, which demonstrate that GFB-887 is well-tolerated and suggest a dose-dependent reduction in urinary Rac1, confirming GFB-887 target engagement in the podocyte,” said Anthony Johnson, M.D., President and Chief Executive Officer of Goldfinch Bio. “Suppressing the TRPC5-Rac1 pathway has the potential to deliver clinically meaningful benefit to patients by reducing proteinuria and, as a result, preserving native kidney function. Supported by the Phase 1 data, we are now underway with our Phase 2 TRACTION-2 study of GFB-887 in FSGS and DN, as we continue to advance our mission of protecting patients from the inevitability of dialysis and kidney transplant by delivering precision medicines for subsets of kidney disease.”

Data from the Phase 1 Clinical Trial

The primary objective of the randomized, double-blinded, placebo-controlled trial was to assess the safety, tolerability, pharmacokinetic (PK) profile and pharmacodynamics (PD) of GFB-887 in healthy volunteers. A key exploratory objective was to characterize changes in urinary Rac1. Urinary Rac1 concentration may predict therapeutic response to TRPC5 inhibition.

The study enrolled 70 subjects, who were randomized four to one to receive GFB-887 at seven dose levels (ranging from 5 mg to 900 mg) or placebo.

Primary Objective: Safety, Tolerability and PK Data

GFB-887 was observed to be well-tolerated at all doses. There were no dose-limiting toxicities, severe adverse events (AEs) or abnormalities in laboratory or clinical assessments. In total, 38 percent of subjects who received GFB-887 reported AEs, compared to 21 percent of subjects treated with placebo. GFB-887-treated subjects reported headache more frequently than placebo-treated subjects (28.6% versus 7.2% respectively). The only other AE that was reported in two or more GFB-887-treated subjects was nausea (3.6%). Slight, asymptomatic reductions in blood pressure were observed in subjects treated at the highest doses.

The PK profile of GFB-887 is consistent with once-daily dosing, with a half-life ranging from 55 to 68 hours. A single 40 mg dose was also shown to exceed the preclinical