SELLAS Announces Completion of Enrollment and Initial Positive Data in Phase 2a Trial of SLS009 in r/r AML
SELLAS has completed enrollment for its Phase 2a trial of SLS009 in relapsed/refractory acute myeloid leukemia (r/r AML) ahead of schedule. The trial includes 30 patients who have not responded to venetoclax-based regimens.
Initial results show promising efficacy with an overall response rate (ORR) of 33% and 50% in the 60 mg QW and 30 mg BIW dosing cohorts, respectively. Median overall survival (OS) was 5.4 months at the 45 mg QW dose, significantly higher than the 2.5 months standard of care. Notably, patients with ASXL1 mutations in the 30 mg BIW cohort achieved a 100% ORR. The trial will now proceed with two additional cohorts focusing on patients with specific genetic mutations, with further updates expected in Q3 2024.
- Completion of patient enrollment ahead of schedule.
- Overall response rate (ORR) of 33% and 50% at 60 mg QW and 30 mg BIW doses, respectively.
- Median overall survival (OS) of 5.4 months at 45 mg QW dose, higher than the 2.5 months standard of care.
- 100% ORR in patients with ASXL1 mutations in the 30 mg BIW cohort.
- SLS009 was well-tolerated with no significant safety issues observed.
- Trial expansion to include two new cohorts targeting specific genetic mutations.
- Positive preliminary data exceeding the targeted ORR of 20% and median OS of 3 months.
- The highest ORR was only observed in specific subgroups, potentially limiting general applicability.
- Median overall survival has not been reached for the 60 mg QW and 30 mg BIW doses, requiring further data.
- Continuation of the trial and further cohort expansion indicate that definitive results are still pending.
- number of patients (30) may affect the generalizability of the trial results.
Insights
The completion of enrollment and initial positive data for SLS009 in a Phase 2a trial targeting relapsed/refractory AML signifies a significant milestone for SELLAS Life Sciences. The overall response rates (ORR) of
Importantly, a
Moreover, the trial's expansion to include additional cohorts for targeted genetic mutations suggests strategic clinical development focused on personalized medicine approaches, which could further enhance the drug's competitive positioning in the AML therapeutic landscape.
From a clinical perspective, the initial data for SLS009 is encouraging. The drug's efficacy, particularly in the patient cohort with ASXL1 mutations, highlights its potential as a targeted therapy in AML. Achieving an overall response rate of
The safety profile is also promising, with no severe treatment-related non-hematologic toxicities reported. The hematologic toxicity profile comparable to that of venetoclax-based regimens provides further support for its potential use in combination therapies. However, cautious optimism is warranted as these are initial data and the full clinical efficacy and safety profile will only be clear with more extensive patient follow-up and additional data expected later this year.
The next steps in the trial will be critical in confirming these findings and ensuring that the drug can meet the unmet medical need in this challenging patient population.
- 30 Patients Relapsed or Refractory to Venetoclax-Based Regimens Enrolled Ahead of Schedule -
- Overall Response Rate (ORR) of
- 45 mg (Safety Dose) Once a Week of SLS009 Showed a Median Overall Survival (OS) of 5.4 Months vs. 2.5 Months with Standard of Care; 60 mg Once a Week and 30 mg Twice a Week Median OS Have Not Been Reached Yet -
-
- Trial Continues with Two Expansion Cohorts of Patients with ASXL1 Mutations and Myelodysplasia-Related Molecular Mutations Other Than ASXL1; Additional Update Expected in Q3 2024 -
NEW YORK, June 10, 2024 (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 the completion of enrollment as well as positive initial data from the ongoing Phase 2a trial of SLS009, a highly selective CDK9 inhibitor, in relapsed/refractory acute myeloid leukemia (r/r AML).
“We are pleased to announce the completion of enrollment in the initial portion of our Phase 2a trial representing a significant milestone in the development of SLS009 in AML,” said Angelos Stergiou, MD, ScD h.c., President and Chief Executive Officer of SELLAS. “There has been a high level of enthusiasm from the clinical sites, trial investigators, and patients, reflecting the significant unmet need in the AML patient population previously treated with venetoclax-based regimens. We are extremely grateful to everyone who has helped us achieve this important milestone ahead of schedule.”
Dr. Stergiou continued: “In addition, we are excited to share very promising initial data from this Phase 2a trial. Efficacy was demonstrated across all cohorts far exceeding the targeted ORR of
Thirty heavily pretreated patients were recruited in 5 centers across the US, reflecting the high unmet need of this refractory/relapsed patient population. Except for one, all patients in this Phase 2a trial had unfavorable/poor cytogenetic and/or molecular genetics risk (
Key Highlights from the Initial Data:
Safety:
- SLS009 was generally well-tolerated with no safety issues observed across all doses.
- There were no dose-limiting and no high-grade treatment-related non-hematologic toxicities. Hematologic toxicities profile was not different from that of venetoclax-based regimens alone.
- 27 patients had at least one efficacy assessment as of May 25, 2024, and were considered evaluable for efficacy.
Efficacy:
- The overall response rate was
29.6% in all evaluable patients, and across all SLS009 doses, with the highest response rate of50% observed at the dosing regimen of 30 mg BIW. - In the first dose level (safety level, one dose level below recommended Phase 2 dose) of 45 mg once a week (QW), the median overall survival among evaluable patients followed for survival was 5.4 months, compared to the expected survival of 2.5 months in patients refractory to and relapsed on standard venetoclax in combination with hypomethylating agents.
- In the second dose level, 60 mg, administered once a week, 3 out of 9 evaluable patients (
33% ) achieved an overall response defined as leukemia-free status that includes complete response (CR), complete response with incomplete hematologic recovery (CRi), and morphologic leukemia-free state (MLFS). Median survival has not been reached. - In the third dose level of 30 mg twice a week, 4 out of 8 patients (
50% ) evaluable to date achieved overall response defined as leukemia-free status that includes complete response (CR), complete response with incomplete hematologic recovery (CRi), and morphologic leukemia-free state (MLFS). Median survival has not been reached. - Observed efficacy outcomes exceeded the target ORR of
20% and mOS of 3 months. - The highest response rates were observed among patients harboring ASXL1 mutations as previously reported. Notably, responses were highly correlated with mutational status, with 6 out of 8 responding patients having myelodysplasia-related somatic mutations and 5 having specifically ASXL1 mutations.
- A
100% overall response rate (CR/CRi/MLFS) was achieved in patients with ASXL1 mutations in the 30 mg BIW cohort to date. - Based on the preliminary findings from this Phase 2a trial, the trial has been expanded to include two additional cohorts consisting of dosing at 30 mg BIW. One cohort will enroll AML patients with ASXL1 mutations and the other AML patients with myelodysplasia-related molecular mutations other than ASXL1. Study enrollment continues and additional updates and data are expected in Q3.
The Phase 2a clinical trial of SLS009 is an open-label, single-arm, multi-center study designed to evaluate the safety, tolerability, and efficacy of SLS009 in combination with venetoclax and azacitidine at two dose levels, 45 and 60 mg. In the 60 mg dose cohort patients were randomized into either a 60 mg dose once per week or a 30 mg dose two times per week. The target response rate at the optimal dose level is
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’ other 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 (formerly GFH009), a small molecule, highly selective CDK9 inhibitor, which is licensed from GenFleet Therapeutics (Shanghai), Inc., for all therapeutic and diagnostic uses in the world outside of Greater China. 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 28, 2024 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
Bruce Mackle
Managing Director
LifeSci Advisors, LLC
SELLAS@lifesciadvisors.com
FAQ
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