April 25 (Reuters) - UK-listed drugmaker Indivior plans to seek shareholder approval next month for a primary listing in the United States, the company said on Thursday, which would add it to a growing list of firms leaving the London stock market.

Indivior had, in February, announced its intent to shift its listing by the middle of the year to the U.S., which, it argued, reflected its growth opportunities as its proprietary treatments are U.S.-centred and U.S.-based investors account for nearly 50% of its overall shareholder base.

The list of UK-based companies that have already listed in the United States includes ARM, the UK's biggest chip company, as well as building supplies firm CRH and plumbing equipment company Ferguson.

Indivior also reaffirmed its annual outlook after logging in a 12% net revenue growth in the first quarter, boosted by strong demand for its Sublocade treatment for opioid use disorder.

However, its adjusted operating profit inched down 1% to $70 million in the three months ended March 31.

The company said it expects its top- and bottom-line growth to accelerate over the rest of 2024, particularly in the second half. (Reporting by Aby Jose Koilparambil in Bengaluru; Editing by Savio D'Souza)