- The combination of lapatinib plus vinorelbine fails to extend PFS vs vinorelbine alone in HER2+ metastatic breast cancer (mBCa) patients who progressed on both lapatinib and trastuzumab.
Why this matters
- This is the first trial to test the efficacy and safety of continuing lapatinib after the failure of both trastuzumab and lapatinib therapies in HER2+ mBCa.
- Open-label multicenter, randomized phase 2 study (n=149) by the Korean Cancer Study Group (KCSG BR11-16).
- The lapatinib+vinorelbine (LV) group (lapatinib dose of 1000 mg daily and vinorelbine dose of 20 mg/m2 on days 1 and 8 every 3 weeks) was compared with the vinorelbine-only (V) group (at a dose of 30 mg/m2 on days 1 and 8 every 3 weeks).
- Primary outcome was PFS at 18 weeks.
- Funding: GlaxoSmithKline; National Cancer Center Korea.
- No difference between groups on:
- PFS at 18 weeks (LV group, 45.9% vs V group, 38.9%; P=.402).
- Objective response rates (19.7% vs 16.9%, respectively; P=.881).
- Median PFS (16.0 vs 12.0 weeks, respectively; HR, 0.86; 95% CI, 0.61-1.22)
- Median OS (15.0 vs 18.9 months, respectively; HR, 1.07; 95% CI, 0.72-1.58).
- Toxicity profiles were tolerable and similar across groups.
- Open-label design.
- Short follow-up.