SELLAS Stock Up 346% in a Year as Cancer Vaccine Trial Nears Its Final 8 Deaths

Core Viewpoint - SELLAS Life Sciences (SLS) has experienced a significant stock increase of 346% over the past year, reaching $5.04, as its Phase 3 REGAL trial for the WT1-targeting cancer vaccine in acute myeloid leukemia (AML) patients approaches completion with 72 of the required 80 patient deaths recorded, indicating a potentially lower-than-expected mortality rate [2][6]. Company Overview - SELLAS Life Sciences is a late-stage clinical biopharmaceutical company focused on immunotherapy for various cancers, currently at a pivotal point due to its ongoing clinical trials [5]. - The company’s stock has seen a recent pullback of 13.4% in the past week, coinciding with the anticipation of Q4 earnings [6]. Trial Progress and Implications - The REGAL trial's slower-than-expected death rate is viewed positively, suggesting that the GPS vaccine may extend long-term survival for AML patients, with only 12 deaths among 66 at-risk patients recorded [3][8]. - The Independent Data Monitoring Committee (IDMC) has cleared the trial twice without modifications, indicating that the trial's two arms remain clearly separated [14]. Institutional Interest - Institutional ownership has surged from approximately 35-72 institutions prior to the interim results to over 171 institutions as of March 2026, with notable accumulation from firms like Vanguard and BlackRock [14]. Market Sentiment - Social sentiment around SELLAS has been very bullish, with scores ranging from 78 to 88 on platforms like Reddit, driven by the trial's progress and institutional accumulation [10][11]. - Analysts have set a consensus price target of $7.83, although the stock is trading near its 52-week high of $6.14, with the final REGAL readout expected by the end of 2026 [12][13].