(Reuters) -U.S. drugmaker Amgen's shares jumped 14% premarket on Friday as the company said it was encouraged by interim trial data on its experimental obesity drug, denting rival stocks but leaving Wall Street frustrated over a lack of details.
Amgen, which is conducting mid-stage studies of its injectable drug MariTide, said, based on interim data, that it was "confident in MariTide's differentiated profile and believe it will address important unmet medical needs."
"The fact that ... the delivery dosing schedule is likely to be monthly or less frequent implies far fewer injection devices than competitors who, for example, are administering a weekly therapy," Amgen's CEO Robert Bradway told investors late on Thursday.
Amgen, however, provided no specifics on the actual data, and said it plans to start a late-stage study later this year.
Mizuho analyst Salim Syed said he acknowledged "the seemingly more upbeat tone" on the drug franchise but "we'd argue that a lot of questions remain unanswered."
Those questions, said Syed, included manufacturing plans, given that rivals Eli Lilly and Novo Nordisk are racing to boost supply, and how Amgen plans to make headway in the commercial market.
Supply of powerful new weight-loss drugs from Lilly and Novo are already falling short of soaring demand, and several other are gunning to grab a share of the market that some analysts expect will reach $100 billion by the end of the decade.
Amgen's comments pulled down shares of rivals on Friday. Eli Lilly was down 2.6%, while Novo Nordisk's Denmark-traded shares were off by nearly 5%. Shares of another weight-loss drug developer, Viking Therapeutics, fell 6% premarket.
Amgen's shares, part of the bluechip Dow Jones index, rose 14.1% to $317.65 in premarket trading.
Its stock is trading 13.9 times its forward 12-month earnings estimates, compared with a forward price-to-earnings ratio of 34.2 for Novo Nordisk and 48.49 for Eli Lilly.
(Reporting by Manas Mishra and Christy Santhosh in Bengaluru; Editing by Sonia Cheema and Devika Syamnath)
