What this phase means
Phase 3: this treatment already looked useful in smaller studies. Now it is tested in a large group, often against standard care or a dummy treatment, to see if it should be approved.
Phase labels are FDA/ICH categories applied to the registry Phase field. They are not a finding that this study succeeded.
What the registry says happens
If you join, the listed intervention(s) are Patritumab deruxtecan, Paclitaxel, or Nab-paclitaxel. The registry lists allocation as randomized. Researchers are looking for other ways to treat breast cancer (BC) that is hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/HER2-) and either unresectable locally advanced or metastatic.
They plan to enroll about 1,000 people at 206 sites. Taking part typically means taking a study drug (or dummy pill), an infusion or injection of a biologic plus check-ins.
Official title (unrewritten)
An Open-label, Randomized, Phase 3 Study to Evaluate Patritumab Deruxtecan Monotherapy Versus Treatment of Physician's Choice in Hormone Receptor-positive, HER2-negative Unresectable Locally Advanced or Metastatic Breast Cancer (HERTHENA-Breast04).
Interventions: Patritumab deruxtecan, Paclitaxel, Nab-paclitaxel, Capecitabine, Pegylated liposomal doxorubicin, Trastuzumab deruxtecan, Rescue Medication
Primary outcome (registry wording): Progression Free Survival (PFS)