Goldfinch Bio Announces Initiation of Open-Label Extension Study for Patients with Focal Segmental Glomerular Sclerosis (FSGS) Enrolled in Phase 2 Clinical Trial of GFB-887


— GFB-887, company’s lead precision kidney medicine product candidate, is a highly potent and selective inhibitor of the TRPC5-Rac1 pathway —

— TRPC5-Rac1 pathway overactivation is key cause of disease in substantial portion of patients with FSGS and other kidney diseases —

CAMBRIDGE, Mass., August 10, 2021 – Goldfinch Bio, a clinical stage biotechnology company focused on discovering and developing precision medicines for the treatment of kidney diseases, today announced that it has dosed the first patient in an open-label extension study for patients with focal segmental glomerular sclerosis (FSGS) enrolled in its Phase 2 TRACTION-2 clinical trial of GFB-887, a highly potent and selective inhibitor of Transient Receptor Potential Canonical Channel 5 (TRPC5)[1]. Anticipated to enroll approximately 35 patients, the extension study is designed to evaluate the long-term safety and tolerability of GFB-887.

“I am thrilled that our understanding of the molecular drivers of kidney disease and our ability to identify associated targets and patient subsets is now enabling the pursuit of investigational precision kidney medicines like GFB-887,” said Katherine Tuttle, M.D., FASN, FACP, FNKF, Executive Director for Research at Providence Health Care and Professor of Medicine at the University of Washington and investigator in the TRACTION-2 trial. “Overactivation of the TRPC5-Rac1 pathway is implicated in the pathogenesis of kidney disease for a large number of patients with FSGS. I look forward to seeing how GFB-887’s inhibition of TRPC5 translates in the clinic, with the potential for near-term reductions in proteinuria and long-term, sustained benefit to patients.”

Anthony Johnson, M.D., President and Chief Executive Officer of Goldfinch Bio commented, “The initiation of the TRACTION-2 open-label extension study is another important milestone as we advance GFB-887 as a potential precision medicine to address the significant unmet need of patients with FSGS and other kidney diseases. We’re grateful to the TRACTION-2 and extension study investigators, clinical research staff and, most importantly, the patients who are participating in these important studies. Working together, I believe we can make precision kidney medicines a new and much-needed therapeutic solution for people living with kidney diseases.”

Currently, patients with kidney diseases, including FSGS, have limited treatment options, which are often associated with difficult short- and long-term side effects. Many patients ultimately require dialysis and kidney transplant, including repeat transplants due to the disease’s reoccurrence. Goldfinch Bio is advancing a pipeline of precision medicines designed to target the underlying causes of kidney disease, with the ultimate vision to save kidneys and end dialysis.

About TRACTION-2 and the Open-Label Extension Study

TRACTION-2 is a multicenter, double-blind, randomized, placebo-controlled Phase 2 trial, evaluating the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of GFB-887 in approximately 125 patients with FSGS, TR-MCD or diabetic nephropathy (DN). The primary objective of the study is to assess the clinical activity of multiple doses of GFB-887 over 12 weeks, as measured by percentage change from baseline in urine protein to creatinine ratio, urine albumin to creatinine ratio, and 24-hour urine protein/albumin excretion. Secondary outcome measures include safety and tolerability and PK of multiple doses of GFB-887. Additional exploratory outcome measures will include changes from baseline in PD biomarkers associated with TRPC5-Rac1 activation.

FSGS patients in the open-label extension study will be enrolled from the ongoing Phase 2 TRACTION-2 multiple ascending dose trial. Patients will have follow-up visits at Weeks 12, 24, 36, 48, and every 24 weeks thereafter through approximately three years from the time of their first dose in the open-label extension study to evaluate long-term safety and durability of response.

Goldfinch expects to report initial clinical data from TRACTION-2 in the first quarter of 2022. For more information about the clinical trial, please visit: (TRACTION-2: NCT04387448; Open-Label Extension: NCT04950114).

About GFB-887

GFB-887 is a once-daily, oral TRPC5 ion channel inhibitor in clinical development for the treatment of kidney diseases, including FSGS, TR-MCD and DN. TRPC5 is a calcium-permeable ion channel implicated in the pathogenesis of kidney disease. Recent evidence demonstrated that TRPC5 and Rac1, a critical regulator of cellular motility, form a vicious cycle that drives pathogenic remodeling of the actin cytoskeleton in podocytes. Overactivation of the TRPC5-Rac1 pathway causes podocyte loss and breach of the filtration barrier, which leads to proteinuria, the hallmark of progressive kidney diseases such as FSGS and DN. Inhibition of TRPC5 and subsequent suppression of the overactivated TRPC5-Rac1 pathway offers a potential point of therapeutic intervention to restore podocyte integrity and halt progression of these diseases. In a Phase 1 clinical trial, GFB-887 was well-tolerated and dose proportional increases in drug exposure of GFB-887 were observed.

About Goldfinch Bio

Goldfinch Bio, Inc. is a clinical stage biotechnology company focused on delivering disease-modifying precision medicines that bring hope and renewed quality of life to people living with kidney diseases. We aspire to save kidneys and end dialysis. Our precision medicine product engine allows us to discover and validate novel targets aimed at understanding the molecular and phenotypic heterogeneity in diverse kidney disease patient populations to identify subsets most likely to respond to our treatments. We have a robust pipeline of novel, precision medicine product candidates targeting kidney diseases with significant unmet need, including two clinical-stage assets. In 2020, Goldfinch Bio was named one of Fierce Biotech’s “Fierce 15” companies. Visit us at to learn more.

1 Patients diagnosed with treatment-resistant minimal change disease (TR-MCD) which is considered a subset of FSGS, are also being enrolled in the Phase 2 open label extension study. The Phase 2 TRACTION-2 trial is enrolling patients with FSGS, TR-MCD and diabetic nephropathy.


Goldfinch Bio Contacts:

Investors: Hannah Deresiewicz
Stern Investor Relations, Inc.

Media: Liz Melone