FDA Clears Autobahn Therapeutics' IND for ABX-002 in Bipolar Depression

Autobahn Therapeutics, a biotechnology firm based in San Diego, has received clearance from the U.S. Food and Drug Administration (FDA) to commence a Phase 2 clinical trial of ABX-002. This trial will explore ABX-002 as an adjunctive treatment for patients suffering from bipolar depression. ABX-002, an orally administered, potent thyroid hormone beta receptor (TRβ) selective agonist, is engineered to boost the central nervous system (CNS) benefits of thyroid hormone biology and ensure drug concentrations are directed to the brain.

Kevin Finney, President and CEO of Autobahn, expressed excitement about expanding their depression treatment program with ABX-002. He emphasized the significant impact of bipolar depression on millions in the United States, highlighting the scarcity of safe and effective treatments that specifically target depressive symptoms. The planned Phase 2 trial aims to establish proof-of-concept for ABX-002 and guide its further clinical development for bipolar depression. With regulatory clearance, the company is eager to advance ABX-002 into another clinical development program this year, alongside the ongoing Phase 2 study for major depressive disorder (MDD).

The upcoming Phase 2 trial will assess ABX-002 as an adjunctive therapy in adult patients experiencing depressive episodes associated with bipolar I or bipolar II disorder. Autobahn will investigate both biological and clinical proof-of-concept for ABX-002, examining various endpoints. These include changes in brain energy metabolism, assessed through phosphorus magnetic resonance spectroscopy (31P-MRS), and alterations in depressive symptoms, measured by the Hamilton Depression Rating Scale (HAMD).

Concurrently, ABX-002 is under evaluation in Autobahn’s ongoing AMPLIFY Phase 2 trial as an adjunctive treatment for patients with major depressive disorder (MDD). Results from this study are anticipated in the latter half of 2025.

Autobahn Therapeutics is focused on developing treatments for neuropsychiatric and neuroimmunologic disorders. The company leverages its brain-targeting chemistry platform to create a portfolio of clinical candidates. Their approach aims to fine-tune CNS exposure, pursue validated clinical and biological targets, and guide development with biomarkers. ABX-002, the lead candidate in their pipeline, is being explored as a potential adjunctive treatment for both major depressive disorder and bipolar disorder depression.

ABX-002 operates as a highly potent and selective thyroid hormone beta receptor (TRβ) agonist. It is designed to optimize the CNS benefits of thyroid hormone biology while reducing peripheral risks associated with synthetic thyroid hormones, such as triiodothyronine (T3). Thyroid hormone agonism has shown effectiveness in multiple placebo-controlled human studies for both MDD and bipolar depression. The activation of cellular energy metabolism pathways by thyroid hormones is crucial for regulating brain bioenergetics, making it particularly suited to address symptoms of atypical depression, a prevalent and underserved subset of MDD.

Nonclinical and clinical studies of ABX-002 have demonstrated its optimized pharmacokinetic properties, effective engagement of target areas in the brain linked with depression, and a favorable safety and tolerability profile.

Autobahn Therapeutics aims to unlock new therapeutic opportunities through precision tuning of CNS exposure, focusing on validated clinical and biological targets, and using biomarkers to guide development. Their San Diego-based operations continue to push the boundaries in treatment for neuropsychiatric and neuroimmunologic disorders.