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Oct 19 (Reuters) - Britain's GW Pharmaceuticals Plc , a developer of marijuana-based epilepsy treatments, said it planned to cancel its listing in London's junior market and would retain listing of its American Depositary Receipts (ADRs) on Nasdaq to simplify trading and cut expenses of dual listing.
The pharmaceutical company, which listed on London Stock Exchange's Alternative Investment Market (AIM) in June 2001, said it would remain headquartered in the UK and would continue to expand its operations in the country.
"With the vast majority of shares now held and traded in the U.S. in the form of ADRs, the time is right to reduce the complexity and expense of a dual listing," Chief Executive Justin Gover said in the statement.
GW Pharma has had a rocky time on the London stock market, and in 2013 opted for a dual listing on the Nasdaq, where it has raised about $800 million from U.S. investors.
The company said 78 percent of its shares are held as ADRs and nearly 94 percent of its trading in the last six months took place on Nasdaq.
The company's delisting move comes at a time when Britain's vote to leave the European Union spells regulatory uncertainty for drug companies, as the London-based European Medicines Agency (EMA), which approves treatments for all EU countries, is expected to have to relocate.
GW Pharma's London-listed shares have more than doubled so far this year, boosting its market value to about 2.55 billion pounds ($3 billion) as of Tuesday's close.
The Cambridge, England-based company has emerged as a coveted takeover target for larger pharmaceutical companies, thanks to its key drug, Epidolex, which uses cannabis-based compounds to treat epilepsy.
Reuters had reported in September that the company was working with an investment bank after receiving interests from other drugmakers for an acquisition.
Its last day of trading on AIM will be Dec. 2, GW Pharma said.
Shares in the company were down 0.7 percent to 846.5 pence at 0740 GMT.
$1 = 0.8145 pounds Reporting by Rahul B in Bengaluru; Editing by Amrutha Gayathri