Investing.com -- Nanobiotix shares rose 12% following a report that Johnson & Johnson is studying a potential takeover of the French biotechnology company.

La Lettre reported that J&J is examining a takeover of Nanobiotix, which is partnered with the healthcare giant on the development of a cancer drug. Representatives for J&J and Nanobiotix did not immediately respond to requests for comment.

The stock initially gained as much as 15% before paring gains to up 4% later in the session.

Van Lanschot Kempen analyst Chiara Montironi, who has a buy rating on the stock, wrote in a note that Nanobiotix management indicated a journalist from La Lettre reached out after rumors circulated within the investor community. The company has "no indication of interest from J&J for a potential takeover," the analyst said.

Van Lanschot Kempen said that a "takeout at this stage is unlikely," given that under their partnership J&J has the exclusive license to NBTXR3, "meaning the full strategic and the majority of the financial ownership."

According to Bloomberg, Nanobiotix is not aware of Johnson & Johnson studying taking control of the company.