Astragalus-containing Chinese Herbal Combinations for Advanced Non-small-cell Lung Cancer: a Meta-analysis of 65 Clinical Trials Enrolling 4751 Patients

Background: Non-small-cell lung cancer (NSCLC) is a leading cause of death. Interventions to reduce mortality in patients with NSCLC represent a patient-important field of research. Little is known about interventions used outside the Western world for NSCLC. One intervention widely used in Asia is astragalus-based herbal preparations.

Methods: We conducted a comprehensive systematic review of all published randomized clinical trials (RCTs) evaluating astragalus-based herbal preparations in NSCLC patients. We searched independently, in duplicate, 6 English language electronic databases and 2 Chinese-language databases. We abstracted data independently, in duplicate on studies reporting of methods, survival outcomes, tumor responses, and performance score responses. We applied a random-effects meta-analysis and report outcomes as relative risks (RR) with 95% confidence intervals (CIs).

Results: We included 65 RCTs enrolling 4751 patients. All trials included the herbal preparations plus platinum-based chemotherapy versus chemotherapy alone. We pooled 7 studies (n = 529) reporting on survival at 6 months and found a pooled RR of 0.54 (95% CI, 0.45 to 0.65, ≤ 0.0001). We included 20 trials (n = 1520) on survival at 12 months and found a pooled RR of 0.65 (95% CI, 0.54 to 0.79, ≤ 0.0001). This effect was consistent at 24 and 36 months. When we applied a composite endpoint of any tumor treatment response, we pooled data from 57 trials and found a pooled RR of 1.35 in favor of herbal treatment (95% CI, 1.26 to 1.44, ≤ 0.0001). Statistical heterogeneity was low across trials.

Limitations: The quality of reporting the RCTs was generally poor. There is also reason to believe that studies reported as randomized may not be.

Conclusions: We found a large treatment effect of adding astragalus-based herbal treatment to standard chemotherapy regimens. There is a pressing need for validation of these findings in well-conducted RCTs in a Western setting.