Site Editor
William J. Gradishar, MD, FACP, FASCO
William J. Gradishar, MD, FACP, FASCO
Posted: Monday, March 10, 2025
Patients with HER2-negative advanced breast cancer typically develop resistance to endocrine therapies, which presents challenges for treatment. An article published in The Lancet Oncology examined findings from a phase II randomized trial that investigated the effects of the next-generation oral selective estrogen receptor degrader (SERD) camizestrant in postmenopausal women with ER-positive, HER2-negative advanced breast cancer. Mafalda Oliveira, MD, of Vall d’Hebron Hospital and Vall d’Hebron Institute of Oncology, Barcelona, and colleagues compared camizestrant with the first approved SERD, fulvestrant, and found that camizestrant (at daily doses of 75 mg and 150 mg) produced a significant improvement in progression-free survival.
A total of 240 patients were included in this open label study. Patients were randomly assigned to receive oral camizestrant at 75 mg (group 1, n = 74), 150 mg (group 2, n = 73), 300 mg (group 3, n = 20), or intramuscular fulvestrant (group 4, n = 73). Clinical efficacy was compared at each dose level using the primary endpoint of investigator-assessed progression-free survival, per Response Evaluation Criteria in Solid Tumors v1.1, which was assessed by intention to treat in all randomly assigned patients.
Findings revealed that the median progression-free survival was 7.2 months (90% confidence interval [CI] = 3.7–10.9 months) in group 1, 7.7 months (CI = 5.5–12.9 months) in group 2, and 3.7 months (CI = 2.0–6.0 months) in group 4. The hazard ratio (HR) for group 1 vs group 4 was 0.59 (90% CI = 0·42–0·82; P = .017), and the HR for group 2 vs group 4 was 0.64 (CI = 0.46–0.89; P = .0090).
Treatment-related adverse events were reported in 39 of 74 patients (53%) in group 1, 49 of 73 patients (67%) in group 2, 14 of 20 patients (70%) in group 3, and 13 of 73 patients (18%) in group 4. Moreover, no treatment-related deaths occurred.
Disclosure: For full disclosures of the study authors, visit www.thelancet.com.
JNCCN Spotlights
