A type of breast cancer with no specific FDA-approved therapy may be on the verge of a breakthrough thanks to a recent clinical trial.
There’s an unmet need in treating a type of breast cancer tumor called triple negative breast cancer (TNBC), which is associated with a high risk of recurrence and poor survival. It refers to tumors that lack estrogen, progesterone and HER2 receptors that allow other breast cancers to be treated in a targeted way. Because there’s no current FDA-approved therapy for TNBC, chemotherapy is the mainstay of management.
Finding targets
“There’s a need for identification of targets for TNBC,” says Dr. Aditya Bardia, a physician at Massachusetts General Hospital Cancer Center and an investigator in a phase II trial for IMMU-132, an antibody drug conjugate targeting an antigen (protein) overexpressed in many tumor types, including most TNBC tumors.
“We utilize the antibody to link a toxic payload and release it to cancer cells, while sparing normal cells,” explains Dr. Bardia.
IMMU-132 is being evaluated in patients with multiple cancer types, including TNBC patients who received an average of five prior therapies since diagnosis.
“The phase II data is very encouraging,” says Dr. Pamela M. Klein, a senior advisor to Immunomedics, the company developing IMMU-132. “Metastatic TNBC remains a difficult cancer to treat, and we’re committed to bringing IMMU-132 to patients.”
Moving ahead
Based on promising data, the FDA granted IMMU-132 breakthrough designation. Immunomedics plans to file for accelerated approval later this year or early next year. Additionally, a phase III global confirmatory trial will open this year.
“There’s great excitement,” says Dr. Joyce O’Shaughnessy, a trial investigator from Baylor; Texas Oncology and U.S. Oncology. “We’re seeing IMMU-132 kill some cancer cells that seem to be resistant to prior therapies. It’s working differently than everything else we have.”