Conditions: Neoplasms, Breast
Keywords: 1st line MBC MBC hormone receptor positive lapatinib trastuzumab HER2 positive aromatase inhibitor
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 369
Healthy volunteers: no

Brief summary:
A study to compare the safety and efficacy of an aromatase inhibitor in combination with lapatinib, trastuzumab or both for the treatment of hormone receptor positive, HER2+ metastatic breast cancer (MBC).

Detailed description:
This Phase III, multicenter, open-label study randomized subjects to one of the three treatment arms:

1. Treatment group A: lapatinib 1000 mg PO once daily + trastuzumab (loading dose of 8 mg/kg) followed by the maintenance dose of 6 mg/kg IV q3weeks + an AI (either letrozole, anastrozole, or exemestane) of Investigator's choice PO once daily.
2. Treatment group B: trastuzumab (loading dose of 8 mg/kg) followed by maintenance dose of 6 mg/kg IV q3weeks + an AI (either letrozole, anastrozole, or exemestane) of Investigator's choice PO once daily.
3. Treatment group C: lapatinib 1500 mg PO once daily + an AI (either letrozole, anastrozole, or exemestane) of Investigator's choice PO once daily.

Treatment continued until disease progression, death, or unacceptable toxicities, whichever came first.

Subjects who discontinued study treatment for reasons other than disease progression were followed-up every 12 weeks until disease progression or death, until the start of post-study treatment anti-cancer therapy (including radiotherapy and surgery), withdrawal of consent, or lost to follow-up, whichever came first.

Arms:
arm 1: Lapatinib 1000 mg PO once daily + Trastuzumab (loading dose of 8 mg/kg) followed by the maintenance dose of 6 mg/kg IV every 3 weeks (q3weeks) + an Aromatase Inhibitor (AI) of Investigator's choice PO once daily. arm 2: Trastuzumab (loading dose of 8 mg/kg) followed by maintenance dose of 6 mg/kg IV every 3 weeks (q3weeks) + an Aromatase Inhibitor (AI) of Investigator's choice PO once daily. arm 3: Lapatinib 1500 mg PO once daily + an Aromatase Inhibitor (AI) of Investigator's choice PO once daily.

Interventions: intervention 1: Lapatinib intervention 2: Trastuzumab intervention 3: Aromatase Inhibitor intervention 4: Lapatinib
Intervention descriptions: intervention 1: 1000 mg by mouth once a day intervention 2: Loading dose of 8 mg/kg IV followed by the maintenance dose of 6 mg/kg IV every 3 weeks (q3weeks) intervention 3: Aromatase inhibitor (either letrozole, anastrozole, or exemestane) of investigator's choice given by mouth once daily intervention 4: 1500 mg by mouth once daily

Protocol document: