Silverback Therapeutics Presents Initial Safety Data From Solid Tumor Combo Therapy Trial

Silverback Therapeutics Inc SBTX has presented interim data from a Phase 1/1b study of SBT6050 as a monotherapy and in combination with Merck & Co Inc's MRK Keytruda (pembrolizumab).
Data were shared at the 2021 European Society for Medical Oncology Congress (ESMO21).
As of August, 40 patients with advanced or metastatic HER2-expressing or amplified solid tumors were enrolled in the trial.
The most frequent treatment-related adverse events included injection site reactions, fever and chills, hypotension, nausea, vomiting, and fatigue.
These mainly were mild or moderate, and severe/serious adverse events were reported.
At higher dose levels, dose-limiting toxicities (DLTs) were observed, including Grade 3 hypotension, injection site reaction, fever, and hypoxia. These DLTs were resolved with supportive care.
Mild or moderate Cytokine release syndrome (CRS) was observed.
Early signals of anti-tumor activity were observed in a heavily pre-treated, heterogeneous population.
Among 18 evaluable patients, one with HER2 IHC 2+ NSCLC had a confirmed partial response maintained at the most recently available scan obtained at 36 weeks post-enrollment and eight weeks after discontinuing study treatment.
In addition, stable disease was reported in seven patients.
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Check out our coverage of the European Society for Medical Oncology Congress (ESMO21)