|The following article features coverage from the 2019 San Antonio Breast Cancer Symposium. Click here to read more of Cancer Therapy Advisor‘s conference coverage.|
Adjuvant paclitaxel and trastuzumab may provide the same benefit for patients with low-risk, HER2-positive early breast cancer compared with historical controls. These findings were presented at the 2019 San Antonio Breast Cancer Symposium (SABCS) in San Antonio, Texas.
Although adjuvant paclitaxel and trastuzumab is commonly used in clinical practice, the safety and efficacy data that support its use are from a single-arm trial.
“It would have been a very difficult to do a meaningful randomized trial,” said poster discussant Antonio Wolff, MD, professor of oncology, Johns Hopkins School of Medicine in Baltimore, Maryland.
Patient data were pooled for 19,087 patients with low-risk, HER2-positive early breast cancer from 5 randomized clinical trials submitted to the U.S. Food and Drug Administration.
Overall, patients who received trastuzumab with anthracycline, cyclophosphamide, and taxane (ACTH) or trastuzumab with taxane and carboplatin (TCH) served as external controls. In addition, patients who received anthracycline, cyclophosphamide, and taxane (ACT) served as an external control group. All external controls were matched to patients from the Adjuvant Paclitaxel and Trastuzumab trial (ClinicalTrials.gov Identifier: NCT00542451) who received paclitaxel and trastuzumab.
The rates of 5-year invasive disease-free survival (IDFS) were comparable for patients who received paclitaxel and trastuzumab compared with patients who received ACTH or TCH (96.5%; 95% CI, 93.6-98.1 vs 92.9%; 95% CI, 88.2-95.8), as was the 5-year overall survival rate (99.3%; 95% CI, 97.2- 99.8 vs 97.4%; 95% CI, 94.5-98.7).
However, compared with paclitaxel and trastuzumab, ACT had a worse 5-year IDFS rate (96.1%; 95% CI, 91.5-98.2 vs 83.5%; 95% CI, 76.5-88.6) and 5-year overall survival rate (99.3%; 95% CI, 95.3-99.9 vs 94.0%; 95% CI, 88.8-96.8).
According to the researchers, these exploratory analyses “further support” the use of de-escalated therapy in patients with low-risk HER2-positive early breast cancer.
Disclosure: Some of the study authors disclosed financial relationships with the pharmaceutical industry. For a full list of disclosures, please refer to the original abstract.
Read more of Cancer Therapy Advisor‘s coverage of SABCS by visiting the conference page.
- Amiri-Kordestani L, Xie D, Bloomquist E, et al. An FDA analysis of survival outcomes comparing adjuvant paclitaxel and trastuzumab trial (APT) to an external control from historical clinical trials. Poster presentation at: 2019 San Antonio Breast Cancer Symposium; December 10-14, 2019; San Antonio, TX. Abstract PD4-08.