atezolizumab + platinum-based chemotherapy

Atezolizumab + platinum-based chemotherapy is a **combination regimen** used primarily as first-line treatment for several advanced cancers, most notably extensive-stage small cell lung cancer (ES-SCLC) and metastatic non-small cell lung cancer (NSCLC) without EGFR or ALK genomic alterations. **Atezolizumab** is a humanized IgG1 monoclonal antibody that targets programmed cell death ligand 1 (PD-L1), blocking its interaction with PD-1 and B7.1 on T cells, thereby restoring and promoting anti-tumor immune responses[2][3][4][5][6][8][9]. **Platinum-based chemotherapy** (typically carboplatin or cisplatin, often combined with agents like etoposide, paclitaxel, or pemetrexed) exerts its anti-cancer effect through DNA crosslinking, causing apoptosis of rapidly dividing tumor cells. The combination improves overall survival and progression-free survival in multiple studies versus chemotherapy alone[1][3][5]. The regimen is typically administered intravenously, with atezolizumab continued as maintenance after initial cycles alongside chemotherapy[1][5]. The combination is developed and primarily manufactured by Roche and its subsidiary Genentech.