A Single-arm, Multicenter Exploratory Clinical Trial of Anlotinib Combined With TQB2450 and the SOX Regimen as First-line Treatment for Advanced Gastric Cancer With Low PD-L1 Expression

"Anlotinib: 10mg, po, d1-14,q3w,until disease progression or unacceptable toxicity.~TQB2450: 1200mg, iv, d1, q3w,until disease progression or unacceptable toxicity. Oxaliplatin: 130mg/㎡, iv, d1,6 cycles.~S-1:40mg, po, bid, d1\~14,6 cycles."