SLS Stock Jumps Overnight: ‘Potent’ AML Drug Data Ahead Of Cancer Summit Fuels Fresh Momentum

Investors are also watching the late-stage GPS immunotherapy trial, which is nearing final analysis with 72 of 80 survival events recorded.

• The company flagged “potent” preclinical data for its AML drug SLS009 ahead of the AACR 2026 conference.
• CEO Angelos Stergiou called the findings “compelling,” highlighting activity even in high-risk AML mutations like ASXL1 and TP53.
• Sellas recently enrolled its first patient in a Phase 2 AML trial, targeting hard-to-treat groups.

Shares of Sellas Life Sciences Group, Inc. (SLS) jumped nearly 6% in overnight trading on Wednesday after the company flagged “potent” new preclinical data for its acute myeloid leukemia (AML) drug SLS009, with the findings set to be unveiled at a cancer conference next month.

SLS stock recorded its second straight session of losses on Tuesday, declining nearly 6% to $5.04.

CEO Flags ‘Compelling’ SLS009 Findings

The company said it will present the data at the American Association for Cancer Research (AACR) 2026 in San Diego, drawing investor focus to its advancing acute myeloid leukemia (AML) program.

Sellas said early lab data show that SLS009 helps drive leukemia cells toward self-destruction by blocking the signals that normally keep them alive, including proteins such as MCL-1 and Survivin.

The company said the drug increased caspase-3 levels, a key indicator that cancer cells are dying, while lowering MCL-1. With repeated dosing, the drug became more effective, with its potency improving significantly over time and its effects becoming stronger the longer it was used.

In a LinkedIn Post late Monday, CEO Angelos Stergiou said the findings represent “compelling new data,” adding that SLS009 has shown the ability to deliver potent activity even in AML models with high resistance, including those with ASXL1 and TP53 mutations.

Clinical Momentum Builds For SLS009

The update comes days after Sellas announced the first patient enrollment in its Phase 2 trial evaluating SLS009 in newly diagnosed AML patients. The study is expected to enroll around 80 patients across the U.S. and Europe, targeting individuals unlikely to benefit from standard therapies such as Venetoclax and Azacitidine, as well as those showing early resistance.

The trial builds on prior Phase 2 results in relapsed or refractory AML, where SLS009, in combination therapy, delivered overall response rates of up to 50% in certain subgroups, with favorable safety and tolerability. Topline data from the ongoing trial is expected in the fourth quarter.

GPS Phase 3 Trial Nears Key Readout

Investor attention is also focused on Sellas’ lead immunotherapy, GPS (Galinpepimut-S), which is currently being evaluated in a late-stage Phase 3 trial.

The event-driven Regal study is approaching its final analysis trigger, with 72 of 80 required survival events already recorded. The trial is designed to assess whether GPS can improve overall survival in AML patients in remission.

How Did Stocktwits Users React?

On Stocktwits, retail sentiment for SLS was ‘bearish’ amid ‘normal’ message volume.

One user said, “Ignoring the noise and waiting for a news drop when it happens. The longer we wait the higher likelihood of overwhelmingly positive results.” 

Another user said, “Crazy Action Overnight $5.80. Something Bigly Positive gps regal p3 news coming!”

SLS stock has surged over 300% over the past year. 

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