(Reuters) - Indivior Plc's (L:INDV) shares soared as much as 30 percent on Monday after a U.S. court blocked India's Dr.Reddy's Laboratories (NS:REDY) from selling copycat versions of the British drugmaker's bestselling opioid addiction treatment in the United States.
Indivior shares were up 25 percent in early trading on the London Stock Exchange, while Dr.Reddy's Laboratories (NS:REDY) shares fell more than 9 percent in morning trading on the National Stock Exchange.
The U.S. court granted a preliminary injunction on Friday, preventing Dr. Reddy's from re-launching its generic product until the patent litigation is concluded or until the company prevails on an appeal of the injunction.
The ruling came days after Indivior issued a profit warning, citing an "accelerated" U.S. market share loss of star drug Suboxone Film, which wiped out nearly a billion pounds from the company's market value.
Jefferies said the ruling underlined the strength in Indivior's intellectual property.
Suboxone Film generates 80 percent of Indivior's revenue and helps drug users beat their addiction to heroin and is dissolved under the tongue.
Generic rivals in tablet form are already in the U.S. market, which is grappling with an opioid addiction epidemic that killed 33,000 people in 2015.
Indivior, spun-off from Reckitt Benckiser (L:RB) in 2014, has been involved in a number of legal battles with generic drugmakers to stop them from flooding the U.S. market with cut-price versions of its Suboxone Film.