Biogen Inc. (NASDAQ:BIIB) shares are experiencing an upward trend as the U.S. Food and Drug Administration (FDA) has extended the review period for its Alzheimer's treatment, Leqembi Iqlik, by three months, setting a new action date of August 24, 2026. This extension allows the FDA to thoroughly evaluate additional information submitted by Biogen and its partner, Eisai. Leqembi is designed for patients with mild cognitive impairment or mild dementia, the same demographic targeted in clinical trials. Over the past year, Biogen's stock has gained 63.29%, currently trading at $191.66, which is 4.9% above its 20-day simple moving average. The stock's momentum is further supported by the MACD indicator, suggesting easing downside pressure. Additionally, Biogen is acquiring Apellis Pharmaceuticals for approximately $5.6 billion, a move aimed at bolstering its portfolio in immunology and rare diseases. The acquisition includes a contingent value right for shareholders, allowing for potential additional payments based on sales performance.