Aug 1 (Reuters) - Biogen lifted its full-year

earnings forecast on Thursday, as the launch of new treatments

such as rare disease drug Skyclarys is expected to make up for a

market-share loss of its older multiple sclerosis medicines.

The drugmaker has cut jobs, bolstered its pipeline for rare

disease medicines through takeover deals and unveiled new

products, such as Alzheimer's disease drug Leqembi as part of

its plan to return to growth

Sales of Leqembi, which it sells with Eisai ( ESALF ), came

in at $40 million for the second quarter ended June 30. Wall

Street consensus was at $30-$33 million, according to brokerage

Jefferies.

Leqembi sales in the United States have been slow to take

off due to requirements such as additional diagnostic tests,

twice-monthly infusions and regular brain scans.

In a fresh blow to the companies, the drug's application was

rejected in the EU last week.

Revenue for the quarter came in at $2.47 billion, compared

with LSEG estimates of $2.38 billion.

Sales of spinal muscular atrophy drug Spinraza, which is

competing with rival drugs made by Roche and Novartis

, fell 1.8% to $429.1 million, but beat estimates of

$405.24 million.

Skyclarys, which is used to treat a rare genetic disorder

that causes progressive damage to the nervous system, brought in

sales of $100 million for the quarter. Analysts had expected

$92.06 million.

Sales of multiple sclerosis drugs such as Tecfidera fell

4.9% to $1.15 billion.