ADARx prices IPO at $17 per share, AbbVie to buy stake

ADARx Pharmaceuticals priced its initial public offering at $17.00 per share¹, offering 26,250,000 shares of common stock¹. The stock began trading on Nasdaq under the ticker "ADRX."¹ The underwriters were granted a 30-day option to purchase up to 3,937,500 additional shares¹, and shares were expected to be delivered to purchasers on or about September 28, 2026.¹

Alongside the IPO, AbbVie Inc. agreed to purchase, in a concurrent private placement exempt from the registration requirements of the Securities Act of 1933, as amended, a number of shares of common stock that would result in AbbVie owning approximately 4.9% of outstanding shares following the closing of the offering and concurrent private placement, at a price per share equal to the public offering price, provided AbbVie would not purchase more than $100.0 million in shares.¹ Based on the offering size, AbbVie will purchase 5,233,264 shares.¹

ADARx describes itself as a late-clinical stage biotechnology company focused on developing next-generation siRNA therapeutics designed to treat a broad spectrum of diseases¹. Its most advanced program, onvuzosiran, targets prekallikrein for hereditary angioedema prevention, and the company is running a randomized, double-blind, placebo-controlled Phase 3 STOP-HAE clinical trial in 90 adults with Type I or Type II HAE¹, with topline data expected by the end of 2027¹. In August 2026 the FDA granted Fast Track designation for onvuzosiran for prophylaxis to prevent attacks of HAE¹.

The company said net proceeds from the offering and private placement, combined with existing cash, will fund Phase 2 and Phase 3 work on agazisiran, completion of the STOP-HAE trial, Phase 1 and Phase 2 development of ADX-626, and Phase 1 studies for ADX-077 and ADX-199¹. Separately, ADARx entered a May 2025 collaboration with AbbVie under which it received an upfront cash payment of $335.0 million and is eligible to receive additional payments of up to $385.0 million in option extension and option exercise payments, up to $7.45 billion in additional contingent milestone payments, as well as tiered royalties at rates in the high single digits to mid-teens¹.