Pertuzumab Approved to Treat Some Metastatic Breast Cancers
The Food and Drug Administration (FDA) has approved pertuzumab (Perjeta) to treat women with HER2-positive breast cancer that has spread to other parts of the body. Pertuzumab is approved for use in combination with trastuzumab (Herceptin), another anti-HER2 therapy, and the chemotherapy drug docetaxel (Taxotere) to treat women who have not received previous anti-HER2 therapy or chemotherapy.
Pertuzumab is a monoclonal antibody that is believed to work by targeting a different part of the HER protein than trastuzumab.
Production issues may affect the long-term supply of the drug, so the FDA has limited its approval to supplies that have not been affected by those issues. Genentech, the drug’s manufacturer, said that the company is committed to taking steps to resolve these production issues in a timely manner.
The approval was based on the results of a phase III clinical trial in which 808 women with HER2-positive metastatic breast cancer were randomly assigned to receive either pertuzumab, trastuzumab, and docetaxel or trastuzumab, docetaxel, and a placebo. The median progression-free survival of the women receiving pertuzumab was more than 6 months longer than those treated with the placebo (18.5 months versus 12.4 months).
The most common side effects observed in patients receiving the pertuzumab combination were diarrhea, hair loss, a decrease in infection-fighting white blood cells, nausea, fatigue, rash, and peripheral neuropathy.
The drug’s approval includes a Boxed Warning alerting patients and health care professionals to potential risks of birth defects and fetal death. Pregnancy status must be verified prior to the start of treatment.
The FDA approved pertuzumab under its priority review program, which provides for an expedited 6-month review of agents that may offer major advances in treatment.