Benzinga | Jun 30, 2021 11:24AM EDT

Sellas Life Sciences Reports Encouraging Immune Response From GPS Combo Trial In Ovarian Cancer

* Sellas Life Sciences Group Inc (NASDAQ:SLS) has announced updated data and initial immunobiological data from its Phase 1/2 evaluating its lead asset, galinpepimut-S (GPS), in ovarian cancer.

* Conducted in collaboration with Merck & Co Inc (NYSE:MRK), the study is investigating the combination of GPS and (Keytruda) (pembrolizumab) in patients diagnosed with second- or third-line WT1(+) relapsed or refractory platinum-resistant, advanced metastatic ovarian cancer.

* In the cohort of 11 patients, a disease control rate (DCR) of 63.6%, with a median follow-up of 15.4 weeks, was observed.

* Median progression-free survival (PFS) was 11.8 weeks. The landmark PFS rate by log-rank analysis at six months (26 weeks) was 33%.

* All patients are alive, and five patients (45.5%) are continuing to receive investigational therapy.

* Enrollment is ongoing, with a target of approximately 20 total evaluable patients.

* Immune Data showed that GPS induced WT1-specific immune responses with a substantial increase in antigen-reactive T-lymphocytes averaging +242% for CD8+ and +80.5% for CD4+ T-cells from baseline to 18 weeks post-treatment.

* The safety profile of the GPS-pembrolizumab combination was similar to that seen with pembrolizumab alone, with the addition of only low-grade, temporary local reactions at the GPS injection site.

* Price Action: SLS shares are down 8.87% at $11.91 during the market session on the last check Wednesday.