Conclusions
ASPS
RECURRENT OSTEOSARCOMA, SECONDARY
Dual targeting of TGF-β and PD-L1 (TQB2858) did not improve outcomes in refractory or recurrent osteosarcoma and ASPS. However, it showed an acceptable safety profile, encouraging the use of combination therapy in advanced cases. Sometimes, it could overcome secondary resistance to anti-PD-1 monotherapy in selected ASPS. The PD-L1 expression and TGF-β level of mesenchymal cells might not contribute in better patient selection, which needs future validation.