Effectiveness of atezolizumab plus chemotherapy in small-cell lung cancer

This article investigated the safety and effectiveness of atezolizumab (Tecentriq) plus chemotherapy for the treatment of extensive-stage small-cell lung cancer (SCLC). The authors concluded that this treatment is safe and can improve survival of these patients.

Patients with extensive-stage SCLC are usually treated with chemotherapy. However, after this treatment, the outcomes still remain poor. An alternative treatment method is immunotherapy. This treatment uses monoclonal antibodies (laboratory-produced molecules engineered to stimulate the immune system to destroy cancer cells). 

Atezolizumab is a type of immunotherapy. The addition of atezolizumab to chemotherapy may result in an improved response to treatment. The effect on overall survival and safety of atezolizumab in patients with extensive-stage SCLC? are still under investigation.

This study involved 403 patients with SCLC. They were not treated previously. They were randomly assigned to two groups. Group 1 received atezolizumab and chemotherapy (201) patients. Group 2 was given a placebo and chemotherapy (202 patients). The average follow-up period was 13.9 months. 

At follow-up, group 1 had a longer overall survival (12.3 months) than group 2 (10.3 months). The group that received atezolizumab were 30% less likely to die compared with the placebo group. The average time without cancer growing or spreading was also longer in group 1 (5.2 months) compared to group 2 (4.3 months). The group that received atezolizumab were 23% less likely to have cancer progression compared with the placebo group. 

Side effects were reported in 188 patients (94.9%) in group 1 and in 181 patients (92.3%) in group 2. The most common severe to life-threatening side effects experienced were low white cell count (making patients more prone to infection) and anemia (low hemoglobin causing excessive tiredness). 

The authors concluded that atezolizumab therapy combined with chemotherapy resulted in longer survival than placebo in patients with extensive-stage SCLC. 

This study had a short follow-up period. Longer-term studies are needed.