Core Viewpoint - Sanofi's experimental multiple sclerosis drug tolebrutinib faces dual setbacks with regulatory delays in the U.S. and a failed late-stage clinical trial, impacting its potential annual sales peak of $1.7 billion [1][2]. Group 1: Regulatory Delays - The FDA's approval decision for tolebrutinib may be delayed, with further guidance expected by the end of Q1 [1]. - The review process was previously postponed by three months in September [2]. Group 2: Clinical Trial Results - In a late-stage trial for primary progressive multiple sclerosis, tolebrutinib failed to delay the progression of disability in patients [2]. - Sanofi will not seek regulatory approval for this indication, which accounts for approximately 10% of total patients [3]. Group 3: Market Impact - Sanofi's stock price fell by 6.4% in early trading, marking the largest drop in over three months, and has declined 15% year-to-date, underperforming its peers [1][3]. - Analysts express cautious optimism about the drug's approval potential despite current setbacks, citing unmet medical needs and ongoing data submissions for expanded access [2]. Group 4: Financial Implications - The company is conducting an asset impairment test related to tolebrutinib and will provide updates in January, with no impact expected on its main profit indicators or 2025 earnings guidance [2].

Acquisition of Mersana Therapeutics N O V E M B E R 2 0 2 5 Day One's Mission Inspired by the urgent needs of children, Day One creatively and intentionally develops new medicines for people of all ages with life- threatening diseases Q&A Session All Participants 2 Confidential Information. For internal use only. Forward Looking Statements This communication contains forward-looking statements. Forward-looking statements are generally identified by the words "expects", "anticipates", "believes", "intends", ...

Core Viewpoint - Jasper Therapeutics faced a significant setback due to issues with a batch of its investigational antibody drug, briquilimab, which interfered with the clinical trial results for chronic spontaneous urticaria (CSU), leading to a 55% drop in its stock price [1][2]. Group 1: Drug Batch Issue - A problematic batch of briquilimab affected the BEACON Ib/IIa clinical trial results, which involved approximately 40 patients in a randomized, double-blind, placebo-controlled study [1]. - Data from 13 patients indicated that those using the problematic batch showed "lower than expected" improvement in tryptase levels, a key pharmacodynamic outcome for the trial [1]. - The primary efficacy measure, urticaria activity score, showed "no significant impact" for the 10 patients using the affected batch [1]. Group 2: Market Reaction and Financial Impact - Following the announcement, Jasper's stock plummeted by 55%, prompting the company to consider cost-cutting measures, including potential strategic restructuring [2]. - As of March 31, Jasper had $48.8 million in cash and cash equivalents, which may be impacted by the current market environment and investor sentiment [2]. - Analysts from BMO Capital Markets suggested that the batch issue would make it harder for Jasper to attract investors in the current market climate [2]. Group 3: Future Plans and Adjustments - Jasper is investigating the specific reasons behind the batch issue and plans to provide new medication to the affected patients from an earlier cohort that showed efficacy [2]. - The company intends to add 10 to 12 new patients to the affected dosage groups to ensure data robustness, with results expected in Q4 [2]. - The initiation of the IIb clinical trial for briquilimab in CSU has been delayed to mid-2026, and the company will no longer pursue the drug for asthma indications [2][3].