(Bloomberg) -- Shares of Alumis Inc. fell 17% in their trading debut after the clinical stage biopharmaceutical company raised $250 million in a downsized initial public offering with a concurrent private placement.

The company’s shares closed Friday at $13.30 in New York, giving Alumis a market value of about $690 million. Alumis sold about 13.1 million shares Thursday, as well as 2.5 million shares in a concurrent private placement to one of its investors, at $16 each.

Based in the California city of South San Francisco, Alumis focuses on therapies for patients living with immune-mediated diseases who need alternatives to existing treatments, the filing shows. It is developing two Tyrosine Kinase 2 inhibitor product candidates.

The company had a net loss of $155 million in 2023, compared with a net loss of $111.9 million a year earlier, according to the filing.

Alumis had marketed 17.65 million shares for $16 to $18 each. Its largest shareholders before the listing included Foresite Capital Management entities and Baker Brothers Life Sciences LP entities, as well as AyurMaya Capital Management Fund LP, which purchased the private placement shares. 

The offering was led by Morgan Stanley, Leerink Partners, Cantor Fitzgerald and Guggenheim Securities. Its shares trade on the Nasdaq Global Market under the symbol ALMS.

(Updates with closing share price in second paragraph)

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