Drug is designed to bind different region of Her2 than Herceptin.
FDA approved Roche’s Perjeta™ (pertuzumab) for use as combination therapy with Herceptin (trastuzumab) and docetaxel in the treatment of people with Her2-positive metastatic breast cancer (mBC) who haven’t yet received prior anti-Her2 therapy or chemotherapy for metastatic disease. A regulatory filing with the European Medicines Agency is currently under review.
Approval in the U.S. was based on data from the 808-patient Phase III Cleopatra study, which showed that progression free survival averaged 18.5 months for patients treated using Perjeta plus Herceptin and docetaxel chemotherapy, compared with 12.4 months for patients given just Herceptin and docetaxel. Cleopatra also showed that adding Perjeta to Herceptin and chemotherapy was associated with a 38% reduction in the risk of disease worsening or death.
Perjeta is designed to prevent the Her2 receptor from dimerizing with other Her recetors (EGFR/Her1, Her2, and Her4), but binds to a different region of Her2 than Herceptin. “Perjeta attacks Her2-positive tumors differently,” explains Hal Barron, M.D., Roche CMO and head of global product development. “Based on the way the two medicines work together, the combination plus chemotherapy can prolong the time before this aggressive cancer worsens, compared to Herceptin and chemotherapy alone.”