SAN FRANCISCO (Reuters) - Biogen expects revenue from new launches to exceed its current sales by 2028 and does not feel the need to chase additional business development deals, the company's CEO said.

"The view out there in the analyst community is that the future of Biogen depends on the next deal that we do and that's not a view that we share inside Biogen," CEO Chris Viehbacher told Reuters in an interview on Monday during the annual JP Morgan Healthcare Conference in San Francisco.

Last Friday, Biogen offered to buy Sage Therapeutics, its marketing partner on a drug to treat postpartum depression. Sage saw its share price fall around 76% last year after a series of clinical setbacks.

Viehbacher declined to comment on the transaction, citing legal restrictions.

Shares of Biogen have dropped about 42% over the last year.

"While the deal may make financial sense for Biogen, we think it does little to change the narrative around the company, and additional revenue-generating deals are needed to change the company's growth profile," BMO Capital Markets analyst Evan Seigerman said in a research note.

Viehbacher said Biogen as "gained conviction" on the strength of its current pipeline, including amyloid-targeting Alzheimer's drug Leqembi and BIIB080, an experimental drug that targets tau, a different protein found in the brains of Alzheimer's patients.

"We are doubling down in Alzheimer's," the CEO said, noting that news is expected this year on an FDA filing for subcutaneous Leqembi and use of the drug as maintenance therapy.

He acknowledged that Leqembi sales have not lived up to the loftiest expectations, but said the trajectory is solid and the company is shifting its marketing strategy to target newly-diagnosed patients.

Viehbacher said Biogen also has late-stage studies underway with felzartamab in rare immune-related indications including kidney transplant patients and for experimental lupus drugs.

"It is hard to find assets worth paying for ... there is still an expectation of some pretty high premiums in the market," he said.

The CEO said Biogen has "teams of people" at the healthcare conference this week. At last year's meeting, those teams looked at 100 companies and ended up doing two deals: a collaboration to explore molecular glue degraders with Neomorph and the acquisition of Human Immunology Biosciences.