Long-term survival demonstrated with trastuzumab plus docetaxel: 24-month data from a randomised trial (M77001) in HER2-positive metastatic breast cancer

Abstract

555 Background: Trial M77001 investigated trastuzumab (Herceptin; H) in combination with docetaxel (D) vs D alone as first-line treatment in HER2+ MBC and demonstrated significant clinical benefits, including prolonged survival, when H was added to taxane therapy. Here we report updated results 24 months after the last pt entered the trial. Methods: M77001 is a multicentre, randomised trial. Eligibility criteria included: HER2+ disease (95% had IHC 3+ and/or FISH+ disease); no prior chemotherapy for MBC; LVEF >50%. D was given as 100mg/m2 q3w x 6 cycles and H as 4mg/kg loading followed by 2mg/kg wkly until disease progression. Pts progressing on D alone could crossover to receive H. The primary endpoint was ORR, confirmed by an independent radiologist. Results: 94 pts were randomised to each arm (2 pts in the HD arm received no treatment and were excluded). The 24-month cut-off data are shown in the table below. Considerably more pts who received the HD regimen showed long-term survival at the 24-month cut-off analysis. 28 of the HD pts were alive for >3 yrs after randomisation, with 2 pts surviving for >4 yrs (14 and 1 pt, respectively, in the D only group; of the 14 pts who survived >3 yrs several had crossed over to H). H added little to the toxicity profile of D. There are no new safety concerns. The incidence of febrile neutropenia (23% vs 17%) and CHF (2% vs 0%) for HD vs D remains unchanged. Conclusion: In patients with HER2-positive MBC the combination of HD is highly effective and associated with significant clinical benefits over D alone. There is evidence of a long-term survival benefit following the addition of H to the D regimen. These sustainable data strongly support the first-line use of H + taxane in pts with HER2-positive MBC. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Aventis Aventis, Bristol-Myers Squibb, Elan Pharma, Eli Lilly, Italfarmaco Hoffmann-La Roche Roche, sanofi-aventis