KEY TAKEAWAYS
- The study aimed to investigate the real-world efficacy and safety of T-DXd in patients with heavily pretreated HER2+ metastatic/unresectable BC.
- Researchers noticed significant antitumor activity and favorable tolerability of T-DXd.
Early access program (formerly cohort Temporary Authorization for Use) was granted for trastuzumab deruxtecan (T-DXd) based on the DESTINY-Breast01 trial, which demonstrated its efficacy and safety in HER2-positive (+) metastatic/unresectable breast cancer (BC) after ≥2 anti-HER2-based regimens received at a metastatic stage.
Thierry Petit and the team aimed to assess the response to treatment and adverse events associated with T-DXd in patients with BC.
They performed an inclusive analysis within a multicenter real-world early access program, comprising patients with HER2+ metastatic/unresectable BC who had undergone pretreatment with at least 2 lines of anti-HER2 regimens. These patients received T-DXd at a dosage of 5.4 mg/kg intravenously in monotherapy every 3 weeks.
About 459 patients (median age, 58 years; hormone receptor-positive, 67%; brain metastases, 28.1%) were administered T-DXd. Prior to enrollment, 81.7% of patients had undergone radiation therapy, and 76.5% had received surgery. The median number of prior metastatic treatment lines was 4(range, 2-22), with almost all patients (99.8%) having received trastuzumab, 94.8% trastuzumab emtansine, and 79.3% pertuzumab. Follow-up was conducted from September 30, 2020, to March 30, 2021, spanning a median duration of T-DXd treatment of 3.4 (range, 0-7.8) months.
Among 160 patients with available tumor assessment, the objective response rate was 56.7%, with 12.1% experiencing progression. In 57 patients with available brain tumor assessment, complete or partial intracranial response was observed in 35.7% of patients, while 5.4% experienced progression. A total of 17 (3.7%) patients were reported to have interstitial lung disease (ILD), with no ILD-related deaths recorded.
The study concluded that in patients with heavily pretreated HER2+ metastatic/unresectable BC, T-DXd demonstrated significant antitumor activity comparable to that reported in previous clinical studies. Furthermore, T-DXd exhibited favorable tolerability with no new safety signals observed, affirming its potential as a valuable therapeutic option in this challenging clinical setting.
The study was sponsored by AstraZeneca and Daiichi Sankyo.
Source: https://pubmed.ncbi.nlm.nih.gov/38733172/
Petit T, Hajjaji N, Antoine EC, et al. (2024). “Trastuzumab deruxtecan in previously treated HER2-positive metastatic or unresectable breast cancer: Real-life data from the temporary use authorization program in France.” Cancer Med. 2024 May;13(9):e7168. doi: 10.1002/cam4.7168. PMID: 38733172; PMCID: PMC11087844.
