It was a mixed start for the year for Biogen Inc. While making good progress on the pipeline, according to CEO George Scangos the firm's commercial results were not as strong as execs would have hoped.

Overall, the company did report revenues of $2.6 billion, a 20 percent increase compared to the first quarter of 2014, and non-GAAP diluted earnings per share (EPS) were $3.82, an increase of 55 percent over the comparable first quarter of last year. On the earnings webcast, Scangos said Biogen had expected to do even better.

The company suffered a number of headwinds during the quarter, including moderating patient growth for its oral multiple sclerosis (MS) therapy Tecfidera (dimethyl fumarate) in the U.S. and Germany, noted Scangos.

Sales of Tecfidera fell 10 percent compared to the fourth quarter of 2014. The company attributed the decline to the impact of one less shipping week in the U.S. vs. the prior quarter, increased discounts and allowances specific to the first quarter and updated pricing assumptions in Germany.

Despite the fall-off in sales of Tecfidera, Scangos expressed confidence in the MS franchise, which continues to gain market share. Total MS product sales were $2.1 billion compared to $1.7 billion in the same quarter last year.

Tecfidera revenues were $825 million compared to $506 million in first quarter 2014. Those results consisted of $648 million in U.S. sales and $177 million in sales outside the U.S., compared to $460 million and $46 million, respectively, in the comparable 2014 quarter.

The company reported interferon revenues, including Avonex (interferon beta-1a) and Plegridy (peginterferon beta-1a), of $755 million, compared to $761 million in the same quarter last year. Those results consisted of $518 million in U.S. sales and $236 million in sales outside the U.S., compared to $476 million and $285 million, respectively.

Tysabri (natalizumab) revenues were $463 million, compared to $441 million in the same quarter last year. Breaking out those figures showed $273 million in U.S. sales and $190 million in sales outside the U.S., compared to $234 million and $207 million, respectively, in first quarter 2014.

In addition to the strong line-up of MS products, Scangos was enthusiastic about the company's pipeline; in particular, he highlighted the compelling data for aducanumab (BIIB037) presented last month at the 12th International Conference on Alzheimer's and Parkinson's Diseases and Related Neurological Disorders in Nice, France.

Although Biogen provided only a modest update on the product at the American Academy of Neurology (AAN) 67th annual meeting last week, where it generated a great deal of interest, the earnings call did add more color on a planned phase III development program. Doug Williams, executive vice president of research and development, said the firm expects to initiate two phase III registrational studies in the second half of this year. They are anticipated to be 18-month studies, with each enrolling approximately 1,350 subjects with prodromal, or mild Alzheimer's disease. (See BioWorld Insight, April 27, 2015.)

Cambridge, Mass.-based Biogen is also embracing biosimilars, and Scangos noted that its joint venture with Samsung Biologics - Samsung Bioepis – is progressing well and received EMA acceptance and validation of its marketing authorization application (MAA) for its biosimilar candidate for Amgen Inc.'s Enbrel (etanercept). In March, the EMA also accepted and validated the MAA for the JV's infliximab biosimilar candidate.

On a reported basis, GAAP diluted EPS for first quarter 2015 was $3.49, an increase of 73 percent over first quarter 2014. GAAP net income attributable to Biogen for first quarter 2015 was $823 million, an increase of 71 percent vs. the same period in the prior year.

As of March 31, the company reported it had approximately $3.5 billion in cash, cash equivalents and marketable securities.

The company's shares (NASDAQ:BIIB) closed Friday at $401.80, a loss of $28.48.