HR+ MBC: fulvestrant combination therapy beats fulvestrant monotherapy in Chinese meta-analysis

  • Xu L & al.
  • Onco Targets Ther
  • 1 ene. 2018

  • de Miriam Davis, PhD
  • Univadis Clinical Summaries
El acceso al contenido completo es sólo para profesionales sanitarios registrados. El acceso al contenido completo es sólo para profesionales sanitarios registrados.

Takeaway

  • A meta-analysis finds that fulvestrant plus a targeted agent is more efficacious than fulvestrant monotherapy in patients with hormone receptor (HR)-positive metastatic breast cancer (MBC) who had progressed on prior endocrine therapy.

Why this matters

  • Endocrine resistance is nearly universal in MBC.
  • Previous individual studies have shown conflicting results.

Study design

  • Meta-analysis of phase 2 or 3 randomized controlled trials (RCTs) of fulvestrant combination therapy vs fulvestrant monotherapy (n=13 studies; 2247 patients received combination therapy, 1663 received monotherapy) after a search of PubMed, EMBASE, and Cochrane Library.
  • Funding: Youth Science Foundation of Jianxi Province, China.

Key results

  • Across all studies, combination therapy was superior to monotherapy:
    • PFS: HR, 0.73 (95% CI, 0.63-0.86).
    • Objective response rate (ORR): risk ratio (RR), 2.07 (95% CI, 1.67-2.58).
  • In subgroup analysis, fulvestrant+cyclin-dependent kinase (CDK4/6) inhibitor was superior to monotherapy:
    • PFS: HR, 0.51 (95% CI, 0.43-0.61).
    • ORR: RR, 2.72 (95% CI, 1.93-3.83).
  • In subgroup analysis, fulvestrant+PI3K/mTOR inhibitor was superior to monotherapy:
    • PFS: HR, 0.73 (95% CI, 0.66-0.81).
    • ORR: RR, 1.60 (95% CI, 1.15-2.23).
  • In subgroup analysis, fulvestrant+other targeted therapies had no different PFS but superior ORR, 2.19 (95% CI, 1.21-3.98).

Limitations

  • Heterogeneity in drug doses, combination strategy, and treatment regimens.