Finding results in a space where its rivals have consistently fallen short, British drugmaker AstraZeneca (AZ) is proudly touting the success of two of its experimental breast cancer drugs in separate clinical trials. The first, capivasertib, rose to meet both of its goals in a phase-3 trial consisting of breast cancer patients with hormone-positive tumors but low or undetectable HER2 protein levels. Camizestrant, the other candidate, scored in a smaller phase-2 study of post-menopausal patients with metastatic, estrogen receptor-positive disease. Further details will be made public at an upcoming medical conference, as AZ as of now has not cited specific data points in media covering the trial outcomes.
Together, these drugs have the potential to become new treatments for tumors found in roughly 70% of diagnosed breast cancer cases. Using hormone therapy or CDK4/6 inhibitors, the typical route, has seen cancer cells build resistance to those treatment vectors over time. The aforementioned pair’s stellar study results represent a follow-up to AZ’s highly successful Enhertu and its newly found role as the pioneering treatment for individuals with HER2-low tumors.
Competing drugs from Sanofi and Roche proved to be busts in clinical testing, while Radius Health’s entry in the space, elacestrant, was a relative win that is currently eyeing an FDA green light. The key ingredient for Radius was including patients with the ESR1 tumor mutation; though AZ chose not to make this inclusion, the quantifiable impact Radius’ decision had on elacestrant’s advancement is not known.