ADARx Pharmaceuticals files S-1 for Nasdaq IPO under ticker ADRX

ADARx Pharmaceuticals, a San Diego-based biotechnology company, filed an S-1 registration statement on September 4, 2026 for an initial public offering of common stock. The company has applied to list its common stock on The Nasdaq Global Market under the symbol "ADRX," with the offering contingent on that approval.¹

ADARx describes itself as a late-clinical stage biotechnology company focused on developing next-generation siRNA therapeutics, with three clinical-stage programs and two advanced preclinical programs.¹ Its lead hepatic-targeted assets are agazisiran (targeting complement factor B), onvuzosiran (targeting prekallikrein for hereditary angioedema), and ADX-626 (targeting Factor XI for stroke prevention).

The company is conducting a randomized, double-blind, placebo-controlled Phase 3 STOP-HAE trial of onvuzosiran in 90 adults with Type I or Type II HAE, and received FDA Fast Track designation for the drug in August 2026, with topline data expected by the end of 2027 and a potential NDA submission in 2028 if results are positive.¹ Agazisiran is being evaluated in three Phase 2 trials across renal diseases, PNH, and geographic atrophy, with initial data expected in mid- to second half of 2027.¹

In May 2025, ADARx entered a discovery-stage Collaboration and License Option Agreement with AbbVie, receiving an upfront cash payment of $335.0 million and eligibility for up to $385.0 million in option payments plus up to $7.45 billion in milestone payments, along with tiered royalties in the high single digits to mid-teens.¹

Since its founding, ADARx has raised approximately $352.5 million in equity capital.¹ The company had 88,250,216 shares of common stock outstanding as of June 30, 2026, after conversion of preferred stock.¹ Underwriters include J.P. Morgan, Morgan Stanley, TD Cowen, UBS Investment Bank, and LifeSci Capital.