Why Is Apellis Stock Skyrocketing Tuesday? - Apellis Pharmaceuticals (NASDAQ:APLS), Biogen (NASDAQ:BIIB)

Eisai (TYO: 4523) and Biogen (Nasdaq: BIIB) launched Leqembi Pen, a weekly at-home injection for Alzheimer’s, in Japan. The launch follows its inclusion in Japan’s National Health Insurance Drug Price List and approval of the new administration route.

Biogen and Eisai launched LEQEMBI® Pen, a subcutaneous formulation of lecanemab, in Japan for early Alzheimer’s patients. The autoinjector allows weekly at-home administration, reducing clinic visits and healthcare resource use. LEQEMBI Pen is priced at 27,141 JPY per pen under Japan’s National Health Insurance. Eisai leads development, while both companies co-commercialize the product.

Litifilimab (Biogen) showed sustained improvement in skin assessments for cutaneous lupus patients through 52 weeks, per AMETHYST trial data. Response rates increased for those switched from placebo to litifilimab. The drug was well-tolerated, with significant patient-reported skin improvements.

Dutch regulators are investigating Biogen for allegedly restricting a blood test to patients using its MS drug Tysabri, potentially limiting access for competitors' treatments. The test is used to monitor a rare infection risk associated with Tysabri, Biogen's top-selling medication.

Biogen (BIIB) and UCB (UCB.BR) released Phase 3 data for Dapirolizumab pegol, showing lower disease activity in lupus patients. The trial met its primary endpoint, with 50% of patients showing improved BICLA scores compared to 35% on placebo. Post-hoc analysis showed 61.2% and 52.5% of patients responded in at least half or all active organ domains, respectively. Results will be presented at the ACR Convergence 2026 meeting.

Biogen (BIIB) and UCB reported Phase 3 trial results showing dapirolizumab pegol had higher response rates than placebo in lupus patients, with 61.2% vs. 43.2% improvement in organ domains and 52.5% vs. 36.8% improvement across all active domains. The treatment also showed higher rates of sustained low disease activity and remission, but had more adverse events. The companies are collaborating on its development.