SELLAS Life Sciences Group (SLS) Stifel 2026 Targeted Oncology Virtual Forum summary

Company overview and strategic focus

• Focused on late-stage oncology with two main assets: GPS (WT1-targeting immunotherapy, phase III) and SLS009 (selective CDK9 inhibitor, phase II).

• Both assets target acute myeloid leukemia (AML), aiming to shift the treatment paradigm from induction to maintenance.

• GPS and SLS009 have received orphan drug and fast track designations from FDA and EMA.

• Strong financial position with $110 million in cash, supporting upcoming milestones.

GPS (galinpepimut-S) clinical development and data

• GPS is a multivalent WT1-targeting immunotherapy, designed for high immunogenicity and long-term administration.

• Phase II trials in AML showed unprecedented median overall survival: 67.6 months (CR1) and 21 months (CR2), with strong immune responses.

• Phase III REGAL trial in AML (post-CR2) is event-driven; 78 of 80 events reached, with top-line data expected soon.

• Delayed event accrual suggests longer-than-expected survival, increasing optimism for positive outcomes.

• If successful, GPS could become the first-in-class maintenance therapy in AML, with significant commercial potential.

SLS009 (tambiciclib) clinical development and data

• SLS009 is a highly selective CDK9 inhibitor, designed to avoid toxicities seen with less selective drugs.

• Demonstrated synergy with venetoclax, overcoming resistance and improving response rates in AML.

• Phase I/II trials showed 44–58% response rates and median overall survival of 8.8–8.9 months in relapsed/refractory AML, surpassing historical benchmarks.

• Current phase II trial in newly diagnosed and refractory AML patients, using biomarker-driven patient selection; top-line data expected later this year.

• Biomarker work aims to identify responders and expand into solid tumor indications like lung, pancreatic, and liver cancers.