NEW YORK (TheStreet) -- Shares of Biogen (BIIB) - Get Report  are up 4.72% to $239.30 this afternoon after Bernstein initiated coverage of the stock with an "outperform" rating.

The firm has a $282 price target on shares of the Cambridge, MA-based biopharmaceutical company.

Bernstein said that there is no risk of material downside in Biogen stock in the near term. However, 75% of Biogen's profits come from its multiple sclerosis franchise, which is an "aging" market, the firm said in an analyst note cited by Barron's.

The stock's future performance is dependent upon how quickly the MS franchise will decline, what other developments the company will generate for the time being and finally on the success of its promising but high-risk Alzheimer's program.

Like competitor Eli Lilly (LLY), Biogen is in the process of testing an Alzheimer drug, aducanumab, whose early-stage studies looked "promising."

(Biogen is held in Jim Cramer's charitable trust Action Alerts PLUS. See all of his holdings with a free trial.)

Separately, TheStreet Ratings rated this stock as a "buy" with a ratings score of B-. 

The company's strengths can be seen in multiple areas, such as its impressive record of earnings per share growth, increase in net income, revenue growth, largely solid financial position with reasonable debt levels by most measures and reasonable valuation levels. TheStreet Ratings feels its strengths outweigh the fact that the company has had lackluster performance in the stock itself.

You can view the full analysis from the report here: BIIB

Recently, TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this articles's author.

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