Seaport Therapeutics (SPTX) said Thursday it priced an upsized initial public offering of 14.2 million common shares at $18 each.

The transaction is priced at the top of the targeted range and is projected to generate $254.9 million in gross proceeds, the company said.

Underwriters hold a 30-day option to acquire up to 2.12 million additional shares at the public offering price, it said.

The stock is scheduled to debut on the Nasdaq Global Select Market on Friday under the SPTX ticker, with the offering expected to close Monday, Seaport Therapeutics said.