By Colin Kellaher

Pliant Therapeutics Inc. said its upsized initial public offering of nine million shares was priced at $16 apiece, the high end of the expected range.

The South San Francisco, Calif., clinical-stage biopharmaceutical company focused on the treatment of fibrosis said it also agreed to sell an additional 625,000 shares at $16 each to current investor Novartis AG in a private placement.

Novartis held a roughly 6.2% stake in Pliant prior to the IPO.

Pliant, which on Tuesday raised the size of the offering to nine million shares from six million, said it expects gross proceeds of $144 million from the IPO, adding that it granted the underwriters a 30-day option to buy up to an additional 1.35 million shares.

Write to Colin Kellaher at colin.kellaher@wsj.com