Can durvalumab improve the effectiveness of treatment for patients with SCLC?

This study examined the effectiveness and safety of adding durvalumab (Imfinzi) to platinum-etoposide to treat patients with small-cell lung carcinoma (SCLC). The authors found that durvalumab was well-tolerated and improved survival outcomes.

Small cell lung carcinoma (SCLC) is a type of lung cancer that rapidly progresses unless treated. SCLC that spreads to other parts of the body is classified as extensive disease. This makes treatment more difficult. Platinum-etoposide (etoposide with either cisplatin or carboplatin) is the standard first-line treatment for patients with extensive SCLC.

Durvalumab is a biological drug that works by blocking the cancer cell’s ability to turn off immune responses. So, by helping activate immune cells, durvalumab helps boost a patient's response to chemotherapy. It is unclear adding durvalumab to platinum-etoposide makes it safer and more effective in patients with SCLC.

537 patients with extensive SCLC were divided into two groups. 268 patients received durvalumab plus platinum-etoposide. 269 patients received platinum-etoposide. Patients were followed for an average of 14.2 months.

Overall, Patients who received durvalumab plus platinum-etoposide survived for longer on average (13 months) than platinum-etoposide alone (10.3 months). Treatment with durvalumab plus platinum-etoposide decreased mortality risk by 27% compared to platinum-etoposide alone.

54% of the durvalumab group were still alive 1 year later, compared to 40% of the platinum-etoposide group. 34% of the durvalumab group were still alive 18 months later, compared to 25% of the platinum-etoposide group.

Survival without cancer progression was similar in the durvalumab group (5.1 months) and the platinum-etoposide group (5.4 months). After 12 months, more patients in the durvalumab group were still alive without cancer progression compared to the platinum-etoposide group (18% vs. 5%).

98% (durvalumab) and 97% of patients (platinum-etoposide) developed side effects. The most common ones were low white blood cell counts (42% vs. 47%) and low red blood cell counts (38% vs. 47%). Allergic reactions to treatment were also reported (20% vs. 3%), but these were mild and easily treated.

62% of patients in both groups had serious side effects. The most common of these were low white blood cell counts (24% vs. 33%) and low red blood cell counts (9% vs. 18%).

The authors concluded that durvalumab improved the effectiveness of platinum-etoposide for patients with extensive SCLC. The authors suggest that adding durvalumab to first-line treatment is safe and effective.

The manufacturer of durvalumab, AstraZeneca, funded this study. This study was not blinded, meaning that the patients knew which treatment they would receive. This may bias the results.