SELLAS Shares Build on 15% Surge Ahead of $2.98 Billion Pipeline Milestone

SELLAS Life Sciences Group Inc shares jumped 16.7% on Monday to close at $3.35 after the company updated investors on the timing of a late-stage acute myeloid leukemia trial. The stock traded between $2.60 and $3.44 and logged about 22.4 million shares, according to StockAnalysis data. StockAnalysis

SELLAS Life Sciences Group, Inc. is trading at around $1.74 per share in early trading on December 8, 2025, barely changed from the previous close.

Sellas Life Sciences stock has surged roughly 100% year-to-date, closing around $2.14 on Oct. 17, 2025 ts2.tech ts2.tech. In after-hours trading on Oct. 17 it spiked another +38%, briefly touching a new 52-week high ts2.tech. Big investors are piling in: BlackRock disclosed a 5.4% stake in SLS on Oct. 18 ts2.tech, and other funds like Vanguard and Marshall Wace added millions of shares in Q2 quiverquant.com. On the drug-development front, Sellas’s lead AML immunotherapy is in a Phase 3 AML trial, which recently passed an interim safety review ir.sellaslifesciences.com; SLS’s CDK9 inhibitor reported 44% response in a Phase 2 relapsed AML trial ir.sellaslifesciences.com and just showed statistically significant survival gains in a rare T-cell leukemia model ts2.tech ir.sellaslifesciences.com. The company will hold a virtual R&D Day on Oct. 29, 2025 to update investors on these AML programs ts2.tech, and final REGAL results are expected by late 2025 – potential near-term catalysts. Analysts are optimistic: Maxim Group reiterated a “Buy” and $7.00 12-month price target ts2.tech, and the consensus target implies ~220% upside ts2.tech investing.com. Sellas ended Q2 2025 with ~$25M cash on hand ts2.tech and raised another $23.6M through warrant exercises in Sept. 2025 ts2.tech to fund its trials. Overall,

As of mid-October 2025, Sellas Life Sciences trades around $2.10–2.20. This is near the top of its 52-week range and about twice its price at the start of 2025 stockanalysis.com marketbeat.com. Trading volume and volatility have picked up – for instance, on Oct. 14 a massive spike in call-option activity coincided with bullish sentiment marketbeat.com. The stock’s YTD gain far outpaces many small-cap biotechs. Technical platforms note SLS is in “uptrend” territory: the stock is well above its 20-day EMA and 50-day EMA tipranks.com, which TipRanks flags as “Buy” signals. Meanwhile, about 18% of shares are sold short marketbeat.com, a high level that could fuel further swings if any surprise news hits.