SLS009 combined with AZA/VEN showed promising efficacy in heavily-pretreated AML-MR patients, achieving a 46% overall response rate.
Quiver AI Summary
SELLAS Life Sciences Group, Inc. announced promising results from a Phase 2 study of SLS009, a selective CDK9 inhibitor, combined with azacitidine (AZA) and venetoclax (VEN) for treating relapsed or refractory acute myeloid leukemia (AML) with myelodysplastic syndrome-related changes. The study showed a 46% overall response rate overall, improving to 58% in patients who had undergone one prior line of therapy, and a median overall survival of 8.9 months in the least pretreated cohort, significantly exceeding the historical benchmark of approximately 2.6 months. The combination was found to be safe and well-tolerated, with no dose-limiting toxicities. Encouraged by the results, the company plans to expand the study to newly diagnosed AML patients with high-risk features in Q1 2026. The findings were presented at the 67th ASH Annual Meeting.
Potential Positives
- SLS009 in combination with AZA/VEN achieved a 46% overall response rate, highlighting its effectiveness in treating relapsed or refractory acute myeloid leukemia (AML) with myelodysplastic syndrome-related changes (AML-MR).
- The median overall survival (mOS) of 8.9 months in the least pretreated patient cohort significantly exceeds the historical benchmark of approximately 2.5 months, indicating promising therapeutic potential.
- No dose-limiting toxicities (DLTs) were reported, demonstrating the safety and feasibility of the SLS009 regimen.
- Plans for further study expansion targeting newly diagnosed AML with high-risk features indicate a strategic move to capitalize on these promising findings.
Potential Negatives
- Despite promising response rates, the patient cohort is limited (only 35 evaluable patients), which may affect the statistical significance and broader applicability of the findings.
- The press release relies heavily on forward-looking statements that carry inherent risks and uncertainties, which could undermine investor confidence if results do not meet expectations.
- The mention of adverse-risk AML patients (98% of participants) could indicate that the treatment is being tested in a particularly challenging population, raising concerns about its effectiveness in broader patient groups.
FAQ
What were the response rates for SLS009 in the study?
SLS009 combined with AZA/VEN achieved a 46% overall response rate, and 58% in patients with one prior line of therapy.
How does SLS009 compare to historical benchmarks?
The median overall survival for patients in the study was significantly higher than the historical benchmark of approximately 2.5 months.
Was SLS009 safe during the clinical study?
Yes, SLS009 was found to be safe and feasible, with no dose-limiting toxicities observed in the trial.
What are the plans for future studies of SLS009?
SELLAS plans to expand the study of SLS009 plus AZA/VEN in newly diagnosed AML with high-risk features in Q1 2026.
What types of mutations were common among patients in the study?
Common mutations included ASXL1, RUNX1, TP53, and SRSF2, with notable response rates associated with ASXL1 and TP53 mutations.
Disclaimer: This is an AI-generated summary of a press release distributed by GlobeNewswire. The model used to summarize this release may make mistakes. See the full release here.
$SLS Insider Trading Activity
$SLS insiders have traded $SLS stock on the open market 2 times in the past 6 months. Of those trades, 2 have been purchases and 0 have been sales.
Here’s a breakdown of recent trading of $SLS stock by insiders over the last 6 months:
- KATHERINE BACH KALIN purchased 63,400 shares for an estimated $100,806
- NOSTRAND ROBERT L VAN purchased 10,000 shares for an estimated $14,800
To track insider transactions, check out Quiver Quantitative's insider trading dashboard.
$SLS Hedge Fund Activity
We have seen 51 institutional investors add shares of $SLS stock to their portfolio, and 29 decrease their positions in their most recent quarter.
Here are some of the largest recent moves:
- ANSON FUNDS MANAGEMENT LP added 5,757,938 shares (+2093.8%) to their portfolio in Q3 2025, for an estimated $9,270,280
- BLACKROCK, INC. added 1,096,613 shares (+23.9%) to their portfolio in Q3 2025, for an estimated $1,765,546
- MILLENNIUM MANAGEMENT LLC removed 812,523 shares (-72.1%) from their portfolio in Q3 2025, for an estimated $1,308,162
- SUSQUEHANNA INTERNATIONAL GROUP, LLP removed 626,097 shares (-42.0%) from their portfolio in Q3 2025, for an estimated $1,008,016
- GOLDMAN SACHS GROUP INC removed 446,241 shares (-95.9%) from their portfolio in Q3 2025, for an estimated $718,448
- MARSHALL WACE, LLP removed 357,490 shares (-13.2%) from their portfolio in Q3 2025, for an estimated $575,558
- EVERHART FINANCIAL GROUP, INC. added 331,150 shares (+inf%) to their portfolio in Q3 2025, for an estimated $533,151
To track hedge funds' stock portfolios, check out Quiver Quantitative's institutional holdings dashboard.
$SLS Analyst Ratings
Wall Street analysts have issued reports on $SLS in the last several months. We have seen 1 firms issue buy ratings on the stock, and 0 firms issue sell ratings.
Here are some recent analyst ratings:
- Maxim Group issued a "Buy" rating on 07/16/2025
To track analyst ratings and price targets for $SLS, check out Quiver Quantitative's $SLS forecast page.
Full Release
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SLS009 in combination with AZA/VEN achieved a 46% overall response rate across all cohorts, a 58% overall response rate in
patients with one prior line of therapy,
and encouraging survival outcomes in heavily-pretreated AML-MR following prior VEN-based treatment
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Median overall survival (mOS) of 8.9 months in the least pretreated patient cohort; across all cohorts, mOS was not yet reached in
patients with one prior line of therapy vs historical benchmark of approximately 2.5 months
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SLS009 30 mg IV twice weekly added to AZA/VEN was safe and feasible, with no dose-limiting toxicities (DLTs) observed
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Study expansion to evaluate SLS009 plus AZA/VEN in newly diagnosed AML with high-risk features is planned for Q1 2026
NEW YORK, Dec. 07, 2025 (GLOBE NEWSWIRE) -- SELLAS Life Sciences Group, Inc. (NASDAQ: SLS) (“SELLAS’’ or the “Company”), a late-stage clinical biopharmaceutical company focused on the development of novel therapies for a broad range of cancer indications, today announced that clinical data from its ongoing Phase 2 study of SLS009, a highly selective CDK9 inhibitor, in combination with azacitidine (AZA) and venetoclax (VEN) for the treatment of patients with relapsed or refractory (R/R) acute myeloid leukemia (AML) with myelodysplastic syndrome-related changes (AML-MR) after prior VEN-based treatment were presented today at the 67 th American Society of Hematology (ASH) Annual Meeting and Exposition, being held December 6 – 9, 2025, in Orlando, Florida.
In this Phase 2 expansion study, R/R AML-MR patients (N = 35 evaluable) were studied in three separate cohorts (cohorts 3-5) who were previously treated with VEN-based regimens and either relapsed and/or were refractory to VEN and were then treated with SLS009 plus AZA/VEN. The median age of participating patients was 69 years, and 98% of patients had ELN adverse-risk AML, with the most frequent mutations being ASXL1, RUNX1, TP53, and SRSF2.
SLS009 in combination with AZA/VEN demonstrated clinically meaningful activity in patients with R/R AML-MR, and among the 35 evaluable patients, the overall response rate (CR+CRi+MLFS) was 46%, including 29% achieving CR/CRi. Patients harboring ASXL1 or TP53 mutations achieved response rates of 48% (19% CR/CRi) and 57% (29% CR/CRi), respectively. The median overall survival (mOS) was exceedingly higher than the expected 2.6 months in this R/R AML patient population, and in the least pretreated cohort, mOS reached 8.9 months. Across all cohorts, patients with one prior line of therapy experienced the greatest benefit, with a 58% response rate and mOS not yet reached. No dose-limiting toxicities (DLTs) or treatment-related deaths were observed, and the combination was well tolerated.
“These results further reinforce the therapeutic potential of SLS009 to overcome resistance to venetoclax-based regimens by suppressing the expression of MCL-1, a key mechanism of resistance to BCL-2 inhibition in AML,” said Dr. Dragan Cicic, Senior Vice President and Chief Development Officer of SELLAS. “The combination of SLS009 with azacitidine and venetoclax demonstrates encouraging activity in a heavily pretreated population with adverse-risk AML-MR, including those harboring ASXL1 and TP53 mutations. We are particularly encouraged by the strong responses in patients with limited prior therapy and look forward to expanding this combination regimen into newly diagnosed AML with high-risk features.”
Presentation Details:
Title: Phase 2 Study of SLS009 in Combination with Azacitidine and Venetoclax for Relapsed/Refractory AML with MDS-Related Changes (AML-MR) After Prior Venetoclax Treatment
Session Date and Presentation Time : Sunday, December 7, 2025, 6:00 – 8:00 PM EST
Session Title: 616. Acute Myeloid Leukemias: Investigational Drug and Cellular Therapies: Poster II
Location : Orange County Convention Center (OCCC) – West Halls B3-B4
Lead Author: Joshua F. Zeidner, MD, University of North Carolina, Lineberger Comprehensive Cancer Center, Chapel Hill, NC
Publication Number
: 3423
About SELLAS Life Sciences Group, Inc.
SELLAS is a late-stage clinical biopharmaceutical company focused on the development of novel therapeutics for a broad range of cancer indications. SELLAS’ lead product candidate, GPS, is licensed from Memorial Sloan Kettering Cancer Center and targets the WT1 protein, which is present in an array of tumor types. GPS has the potential as a monotherapy and combination with other therapies to address a broad spectrum of hematologic malignancies and solid tumor indications. The Company is also developing SLS009 (tambiciclib) - potentially the first and best-in-class differentiated small molecule CDK9 inhibitor with reduced toxicity and increased potency compared to other CDK9 inhibitors. Data suggests that SLS009 demonstrated a high response rate in AML patients with unfavorable prognostic factors including ASXL1 mutation, commonly associated with poor prognosis in various myeloid diseases. For more information on SELLAS, please visit www.sellaslifesciences.com .
Forward-Looking Statements
This press release contains forward-looking statements. All statements other than statements of historical facts are “forward-looking statements,” including those relating to future events. In some cases, forward-looking statements can be identified by terminology such as “plan,” “expect,” “anticipate,” “may,” “might,” “will,” “should,” “project,” “believe,” “estimate,” “predict,” “potential,” “intend,” or “continue” and other words or terms of similar meaning. These statements include, without limitation, statements related to the GPS clinical development program, including the REGAL study and the timing of future milestones related thereto. These forward-looking statements are based on current plans, objectives, estimates, expectations, and intentions, and inherently involve significant risks and uncertainties. Actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties, which include, without limitation, risks and uncertainties with oncology product development and clinical success thereof, the uncertainty of regulatory approval, and other risks and uncertainties affecting SELLAS and its development programs as set forth under the caption “Risk Factors” in SELLAS’ Annual Report on Form 10-K filed on March 20, 2025 and in its other SEC filings. Other risks and uncertainties of which SELLAS is not currently aware may also affect SELLAS’ forward-looking statements and may cause actual results and the timing of events to differ materially from those anticipated. The forward-looking statements herein are made only as of the date hereof. SELLAS undertakes no obligation to update or supplement any forward-looking statements to reflect actual results, new information, future events, changes in its expectations, or other circumstances that exist after the date as of which the forward-looking statements were made.
Investor Contact
John Fraunces
Managing Director
LifeSci Advisors, LLC
