Evaluating the effectiveness and safety of adebrelimab plus standard chemotherapy as first-line treatment for extensive-stage small cell lung cancer.

This study investigated the effectiveness and safety outcomes of adebrelimab (SHR-1316) plus carboplatin (Paraplatin) and etoposide (Etopophos)-based chemotherapy as first-line treatment for extensive-stage (ES) small-cell lung cancer (SCLC). The data showed that adebrelimab added to standard chemotherapy as first-line treatment significantly improved the overall survival with manageable side effects in these patients.

SCLC is responsible for 15% of all lung cancer diagnoses. Around 70% of SCLCs are diagnosed as extensive stage (ES). ES-SCLC is cancer that has spread beyond the lung, to the lymph node, the other lung, or to other parts of the body. Standard first-line treatment for ES-SCLC is usually chemotherapy with etoposide and/or platinum drugs such as carboplatin. SCLC is usually responsive to chemotherapy, however, this response does not usually last. To improve responses, other therapies are needed.

Immunotherapy has been found to be effective in SCLC. Adebrelimab is an immunotherapy. It targets a protein PD-L1 that can be found on some cancerous cells and shuts down the immune system so they can grow and spread undetected. Blocking PD-L1 restores the capacity of the immune system to attack and kill cancer cells. Previous studies have shown that immunotherapy added to chemotherapy improves the survival outcomes of patients with ES-SCLC. However, the effectiveness and safety of adebrelimab plus carboplatin and etoposide-based chemotherapy as first-line treatment for ES-SCLC are still unknown.

This study involved 462 patients with ES-SCLC. Patients were randomly assigned into 2 groups. Group 1 included 230 patients who received adebrelimab plus carboplatin and etoposide-based chemotherapy combination. Group 2 included 232 patients who received a placebo plus carboplatin and etoposide-based chemotherapy combination. The average follow-up time was 13.5 months.

The average survival was significantly improved in group 1 compared to group 2 (15.3 months vs 12.8 months). Patients in group 1 were 28% more likely to have a better survival than patients in group 2. After 1 year, 62.9% of the patients in group 1 were alive compared to 52% of the patients in group 2.

39% of the patients in group 1 experienced treatment-related side effects compared to 28% of the patients in group 2. The most common side effects were low white blood cell counts, low platelet counts, and low red blood cell counts.  

This study concluded that adebrelimab plus carboplatin and etoposide-based chemotherapy as first-line treatment significantly improved the overall survival with manageable side effects in patients with ES-SCLC.

This study was funded by Jiangsu Hengrui Pharmaceuticals, the manufacturers of adebrelimab. This study was conducted only at institutions in China. The follow-up period was too short.