Alpine Immune Sciences, Inc. (NasdaqGM:ALPN) is weighing options including a potential sale after attracting takeover interest, according to people with knowledge of the matter. The stock gained as much as 17%. The Seattle-based company is working with advisers to weigh a potential transaction, said the people, who asked not to be identified discussing confidential information.

At least one larger pharmaceutical company has spoken to the company about a potential takeover, the people said.