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Stifel is moving off the sidelines when it comes to Biogen . The investment firm upgraded the biotech stock to buy from hold. It also hiked its target price to $202 per share from $144, which signals upside of nearly 32% from Wednesday's close. Analyst Paul Matteis' forecast implies that the stock could rally nearly 32% from here. BIIB YTD mountain BIIB YTD chart "For a cheaper, 'value-y' large cap, Biogen offers unique optionality even if clinical catalysts still have risks," he wrote. "Valuation isn't a thesis in its own right in biotech, but on a EV/sales basis Biogen trades well below peers." Matteis clarified that his upgrade was not a call on the base business, pointing to the company's "mixed" third-quarter results and a fourth-quarter report that should be "just okay." Instead, he pointed to a narrative shift in Alzheimer's treatment as a catalyst for the stock. Matteis also highlighted optionality from Biogen's lupus drugs as another tailwind. "For the stock, the past years have been challenging as Biogen's legacy business remains under competitive pressure, while the launches of lecanemab and skyclaris (acquired from RETA) have lagged investor expectations," the analyst wrote. "That said, with the stock trading at a discount to peers, we do see attractive optionality here with (1) a slowly improving landscape in Alzheimer's where abeta antibodies, like lecanemab, are starting to scale, (2) a potential narrative shift for abeta antibodies via the upcoming readout of LLY and BIIB/Esai preclinical studies, (3) the approval of a lecanemab SQ formulation that may alleviate treatment hurdles and (4) a a few other credible shots on goal in lupus and other I & I indications, as well as a next gen Alzheimer's program targeting tau, that we think are overly discounted by investors," he said. Shares of Biogen have added less than 1% this year, lagging the S & P 500's 15.6% advance in that time.