Biogen shares have a lot more potential upside for investors thanks to positive new data around the company's early Alzheimer's drug, Goldman Sachs said Wednesday. The firm upgraded Biogen to a buy from neutral and increased its price target on shares to $370, about 35% from where they closed on Tuesday. The upgrade followed the company's earnings call, which had a big focus on the drug, lecanemab, an anti-amyloid antibody that is in phase 3 trials. Goldman also raised its revenue estimates for the drug to $14 billion in 2035, compared with prior estimates of $2 billion. "The company is now poised to address the early Alzheimer's disease market in 2023+ following the recent topline lecanemab Ph3 (CLARITY-AD) data," Goldman analyst Salveen Richter said in a note. "While investors are generally cautious into the full presentation at CTAD," or the Clinical Trials on Alzheimer's Disease congress on Nov. 29, "our discussions with leading neurologists and management lead us to believe that the results are clinically meaningful (given the benefit across multiple endpoints, positive trend over time, and safety profile), notwithstanding competitor assets." The firm expects phase 3 data for Roche's gantenerumab at the event on Nov. 29 and Eli Lilly's donanameb by mid-2023. Without lecanemab, discounted cash flow value is $190/share, Richter said. Biogen partner Eisai plans to submit for full approval in the U.S., European Union and Japan in the first quarter of next year and Goldman anticipates it will be successful. "With BIIB shares now trading at ~$270 post the topline CLARITY-AD data, there is roughly ~$80/share reflected in the stock for Alzhiemer's disease," Richter said. "This $80/share for Alzhiemer's corresponds to ~$12 billion in BIIB market cap or ~$7 billion in peak WW lecanemab sales (based on a 3.5x multiple and the 50-50 profit split with Eisai)."