ADARx Pharmaceuticals on Monday said it plans to sell nearly 21.9 million shares at between $15 and $17 apiece in its initial public offering.

At the $16 midpoint of that price range, the San Diego clinical stage biotechnology company said it expects net proceeds of about $318.6 million, or roughly $367.4 million if the underwriters exercise an option to buy an additional 3.28 million shares.

ADARx said biopharmaceutical company AbbVie has agreed to buy shares in a concurrent private placement that would result in AbbVie owning a roughly 4.9% stake, which would result in about an additional $78.5 million in proceeds at the $16-a-share pricing midpoint.

AbbVie and ADARx last year inked a collaboration agreement potentially worth more than $8 billion to ADARx to advance the company's novel siRNA therapeutics across multiple therapeutic areas.

ADARx said it expects the proceeds from the offering and private placement, coupled with its existing resources, will be sufficient to fund its projected operating expenses and capital-spending needs into 2030.

ADARx said it would have about 105.5 million shares outstanding after the IPO and private placement, assuming an exercise of the overallotment option, for a market capitalization of around $1.69 billion at the $16-a-share pricing midpoint.

The company said it has applied to list its shares on the Nasdaq Global Select Market under the symbol ADRX.