NEW YORK (TheStreet) - It's a brutal day for Biogen (BIIB - Get Report), and deservedly so, said TheStreet's Jim Cramer on CNBC's "Mad Dash" segment. 

Shares are down 16.5% on Friday after the company's earnings missed on revenue expectations and said its multiple sclerosis drug will only grow 6% to 8%, slower than its previous estimates of 14% to 16%, explained Cramer, the co-manager of the Action Alerts PLUS portfolio.

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Biogen BIIB data by YCharts

Its Tysabri drug won't work as a treatment for stroke, which is also disappointing investors. There's a lot of "gaffes" in this report, Cramer said. 

He turned his attention to other biotech faves, like Regeneron (REGN - Get Report) and Gilead Sciences (GILD - Get Report). 

Regeneron is on the "verge of getting approval" for its anti-cholesterol drug, while Gilead -- which is a cash flow machine with no debt -- will likely make an acquisition in the not-to-distant future, Cramer concluded.

At the time of publication, Cramer's Action Alerts PLUS had no position in companies mentioned.