LONDON (Reuters) - Investor HgCapital has sold British pharmaceutical company Mercury Pharma to private equity firm Cinven for 465 $732 million.

"The realization of Mercury Pharma marks the continued development of HgCapital's investment focus in the healthcare sector," said HgCapital's head of healthcare, Philipp Schwalber, in a statement on Friday.

"We continue to seek out businesses that enjoy niches of secular growth despite the challenges facing much of the healthcare space," he said.

HgCapital bought the 25-year-old pharmaceutical firm, which sells niche prescription off-patent products in the UK, Ireland and the Netherlands, in 2009.

It said its listed investment trust HgCapital Trust expects to receive 35.4 million pounds in cash on the sale completion and further potential proceeds of 1 million pounds over the next 30 months.

($1 = 0.6352 British pounds)

(Reporting by Brenda Goh, editing by Rosalba O'Brien)