The cumulative incidence of cardiac events at 6 years was slightly higher with the addition of trastuzumab immunotherapy; however, the late development of cardiac events is infrequent, a new study published online ahead of print in the Journal of Clinical Oncology has shown.1
The NCCTG (Alliance) N9831 trial compared adjuvant doxorubicin plus cyclophosphamide followed by weekly paclitaxel (arm A), paclitaxel then trastuzumab (arm B), or paclitaxel plus trastuzumab followed by trastuzumab alone (arm C) in patients with HER2-positive breast cancer.
For this long-term analysis of cardiac safety, researchers assessed the cumulative incidence of cardiac and left ventricular ejection fraction (LVEF) in 1,944 women who proceeded to therapy after doxorubicin and cyclophosphamide.
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Results showed that the 6-year cumulative incidence of cardiac events was 0.6%, 2.8%, and 3.4% in arms A, B, and C, respectively. Researchers observed 2 cardiac deaths in arm A, 1 in arm B, and 1 in arm C.
The study demonstrated that age 60 years or older, LVEF <65%, and antihypertensive medication use were associated with an elevated risk of cardiac events in arms B and C.
“Trastuzumab (in the context of anthracycline- and taxane-based therapy) continues to have a favorable benefit-risk ratio,” the authors concluded.
- Advani PP, Ballman KV, Dockter TJ, et al. Long-term cardiac safety analysis of NCCTG N9831 (Alliance) Adjuvant Trastuzumab trial [published online ahead of print on September 21, 2015]. J Clin Oncol. doi: 10.1200/JCO.2015.61.8413.