If Indivior moves its primary listing, it would join a growing list of companies leaving London, where lower valuations compared with the United States have left Britain struggling to prevent companies exiting and to lure IPOs.

It said it would maintain its secondary listing in London.

Indivior forecast 2024 adjusted operating profit in the range of $330 million to $380 million, after annual profit for the year ended Dec. 31 rose to $269 million.

Shares in the FTSE 250 company traded about 16% higher at 1,565.78 pence by 0836 GMT, placing them at the top of the midcap index.

Indivior said a move to the U.S. would reflect its current and future growth opportunities as its proprietary treatments are U.S.-centred and the group's U.S.-based investors are nearing 50% of its overall shareholder base.

The drugmaker also said it expected a primary U.S. listing would attract more U.S. investors and analysts by elevating the group's leadership profile in addiction treatment in the U.S. markets, and allow for inclusion in major U.S. indices over time.

Some of the prized companies that have switched to U.S. listings include British chip designer Arm Holdings that listed on the Nasdaq in September.

Earlier this month, shareholders in TUI voted to remove Europe's largest travel operator from the London Stock Exchange.

A top investor in Pearson has called for the education company to do the same.

(Reporting by Aby Jose Koilparambil in Bengaluru; Editing by Savio D'Souza and Barbara Lewis)