Pyxis Oncology’s maMICVO Demonstrates Synergistic Tumor Inhibition with Anti-PD-1
maMICVO monotherapy produced dose-dependent tumor inhibition in a syngeneic MOC2 HNSCC model, with 6 mg/kg yielding strongest growth suppression. Combination of maMICVO with anti-mouse PD-1 showed synergistic anti-tumor activity and enhanced CD8/Treg ratio, supporting Phase 1/2 trials of MICVO plus pembrolizumab.
1. Preclinical Efficacy of maMICVO
In a syngeneic MOC2 head and neck squamous cell carcinoma model, maMICVO monotherapy produced dose-dependent inhibition of EDB+FN–expressing tumors, with 6 mg/kg showing the strongest suppression. Treatment also reduced regulatory T cells and increased CD8 T cell-to-Treg ratios, creating a more immunotherapy-permissive microenvironment.
2. Synergy with Anti-PD-1 in Refractory HNSCC Model
When combined with anti-mouse PD-1, maMICVO achieved synergistic tumor growth inhibition in an immune-refractory HNSCC model, outperforming monotherapy with either agent. Bliss independence analysis confirmed synergy, highlighting maMICVO’s potential to enhance responses in PD-1 resistant tumors.
3. Clinical Development and Next Steps
These preclinical findings support ongoing clinical development of MICVO as both monotherapy and in combination with pembrolizumab for recurrent/metastatic HNSCC. A Phase 1 monotherapy update is expected mid-2026, with Phase 1/2 combination dose escalation results anticipated in the second half of 2026.