Share on Facebook
Share on Twitter
Share on LinkedIn
Share by Email
Print
Adding pertuzumab to adjuvant chemotherapy and trastuzumab can improve long-term outcomes in patients with operable, HER2-positive early breast cancer, according to updated results from the phase 3 APHINITY trial.
Pertuzumab provided a significant improvement in invasive disease-free survival (IDFS) and a trend toward improvement in overall survival (OS) at 8 years.
“The trend towards a benefit for the overall survival was influenced strongly by the node-positive cohort, whereas the node-negative cohort didn’t show any differences,” said Sibylle Loibl, MD, PhD, of the German Breast Group Forschungs GmbH in Germany.
Dr Loibl presented these findings in an ESMO Virtual Plenary.
The phase 3 APHINITY trial (ClinicalTrials.gov Identifier: NCT01358877) included 4805 patients with HER2-positive, operable breast cancer who were randomly assigned to receive pertuzumab (n=2400) or placebo (n=2405), each in combination with chemotherapy and trastuzumab, within 8 weeks of surgery.
IDFS Results
The study’s primary endpoint was IDFS, and the addition of pertuzumab significantly improved IDFS. The 8-year IDFS rate was 88.4% with pertuzumab and 85.8% with placebo (hazard ratio [HR], 0.77; 95% CI, 0.66-0.91).
The benefit observed with pertuzumab was driven by patients with node-positive disease, Dr Loibl noted. In the node-positive cohort, the 8-year IDFS was 86.1% with pertuzumab and 81.2% with placebo (HR, 0.72; 95% CI, 0.60-0.87). There was no benefit in the node-negative cohort (92.3% vs 93.3%; HR, 1.01; 95% CI, 0.72-1.42).
Among patients with hormone receptor-positive disease, the 8-year IDFS was 88.9% with pertuzumab and 86.1% with placebo (HR, 0.75; 95% CI, 0.61-0.92). In the hormone receptor-negative cohort, the 8-year IDFS rate was 87.5% with pertuzumab and 85.2% with placebo (HR, 0.82; 95% CI, 0.64-1.06).
Dr Loibl said these results suggest that hormone receptor status should not guide pertuzumab treatment decisions, but patients with node-positive disease derive a benefit from pertuzumab.
OS and Safety
There was no significant difference in OS between the treatment arms. The 8-year OS rate was 92.7% with pertuzumab and 92.0% with placebo (HR, 0.83; 95% CI, 0.68-1.02; P =.078).
However, there was an OS benefit with pertuzumab among patients with node-positive disease. The 8-year OS rate was 91.1% with pertuzumab and 89.2% with placebo (HR, 0.80; 95% CI, 0.63-1.00).
There was no significant difference in OS between treatment groups in the node-negative cohort. The 8-year OS rate was 95.5% with pertuzumab and 96.4% with placebo (HR, 0.99; 95% CI, 0.64-1.55).
Primary cardiac adverse events occurred in less than 1% of patients in both treatment arms. Heart failure (class III with a left ventricular ejection fraction decrease) occurred in 0.7% of patients in the pertuzumab arm and 0.2% of those in the placebo arm. There were 3 cardiac deaths in the pertuzumab arm and 4 in the placebo arm.
Disclosures: This study was supported by Roche. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Reference
Loibl S, Jassem J, Sonnenblick A, et al. Adjuvant pertuzumab and trastuzumab in patients with early HER-2 positive breast cancer in APHINITY: 8.4 years’ follow-up. ESMO Virtual Plenary; July 14-15, 2022. Abstract VP6-2022.
This article originally appeared on Cancer Therapy Advisor
