Targeted Drug Extended Median Survival by About Six Months Versus Chemotherapy in Advanced Triple-Negative Breast Cancer Trial

A new antibody-drug conjugate nearly doubled the time before disease progression and extended overall survival when tested as first-line therapy in patients with advanced triple-negative breast cancer who were not candidates for immune-based treatments.

More than 640 patients participated in the international trial. Patients receiving the targeted drug recorded a median progression-free survival of almost 11 months, compared with just under 6 months for those given chemotherapy.

5 years with chemotherapy. Nearly two-thirds of patients on the targeted drug experienced tumor shrinkage, versus fewer than one-third on chemotherapy. Tumor responses lasted more than one year on average with the new treatment, and a small number of patients showed complete disappearance of detectable tumors on imaging.

The most common side effects of the targeted drug were mouth sores, nausea, and hair loss. Most mouth and eye-related side effects were mild to moderate. Serious treatment-related side effects occurred at similar rates in both groups, yet fewer patients discontinued treatment due to side effects in the targeted-drug arm.

No treatment-related deaths occurred during the trial. Triple-negative breast cancer accounts for roughly 10% to 20% of breast cancer cases. Nearly 70% of patients with advanced disease are not candidates for immune-based treatments, leaving chemotherapy as the standard first option.

The antibody-drug conjugate uses a targeting antibody that recognizes a protein found in high amounts on many breast cancer cells. Once attached, the cancer cell internalizes the attached chemotherapy, concentrating the drug inside tumor cells rather than throughout the body. com on June 11, 2026, and written by William A.

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