KEY TAKEAWAYS
- The phase 3 CAPSTONE-1 study aimed to assess adebrelimab + chemo’s OS benefits in ES-SCLC.
- The result concluded that adebrelimab + chemo boosts long-term SCLC survival with manageable side effects.
In the CAPSTONE-1 study, researchers found that using adebrelimab with chemo as the first treatment for extensive-stage small cell lung cancer (ES-SCLC) significantly increased overall survival (OS) compared to using a placebo with chemo. About three years after the last patient joined the study, Ying Cheng and other researchers aimed to provide updated results.
In the study, around 462 patients with previously untreated ES-SCLC were randomly assigned in a 1:1 ratio to receive either 4-6 cycles of adebrelimab (20 mg/kg, iv, d1, q3w) or placebo. Both groups were given carboplatin (AUC 5, d1, q3w) plus etoposide (100 mg/m2, d1, d2, d3, q3w). This was followed by maintenance therapy with adebrelimab or placebo. The primary endpoint was aimed to attain OS among the patients.
As a result, the median follow-up was 15.1 months for all patients in the adebrelimab group and 12.8 months in the placebo group. The median follow-up for censored patients was 45.8 months and 42.5 months, respectively.
The OS events occurred in 188 (81.7%) patients in the adebrelimab group and 212 (91.4%) in the placebo group. The median OS was 15.3 months (95% CI 13.2-17.3) with adebrelimab plus chemo compared to 12.8 months (95% CI 11.3-13.9) with placebo plus chemo (HR 0.73, 95% CI 0.60-0.89; one-sided P=0.0008). An improvement of over 10% in the OS rate was observed at 12, 24, and 36 months in the adebrelimab group compared to the placebo group. The OS benefits of adebrelimab remained consistent across clinically relevant subgroups. No new safety signals were identified.
The interventional study concluded that after an extended period of observation, the inclusion of adebrelimab in combination with chemotherapy consistently showed OS advantages, accompanied by manageable side effects. This continued positive outcome further solidifies the recommendation of this regimen as a promising first-line treatment option for ES-SCLC. This study is sponsored by Jiangsu HengRui Medicine Co., Ltd.
Source: https://cslide.ctimeetingtech.com/immuno23hybrid/attendee/confcal/show/session/34
Clinical Trial: https://clinicaltrials.gov/study/NCT03711305
Cheng Y et al. “Adebrelimab plus chemotherapy (chemo) as first-line treatment for extensive-stage small-cell lung cancer (ES-SCLC): 3-year update of the phase 3 CAPSTONE-1 study”. Presented at ESMO IO 2023. (Abstract: 84P)
