Herceptin Biosimilar Demonstrates Equivalence in Comparative Phase 3 Study

An investigational biosimilar to trastuzumab (Herceptin) demonstrated positive results from a phase 3 comparative study.

PF-05280014 is a monoclonal antibody designed as a potential biosimilar of trastuzumab for HER2-positive breast cancer and gastric cancer, according to a press release.

The REFLECTIONS B327-02 study was a pivotal, double-blind, randomized, comparative safety and efficacy phase 3 trial of biosimilar PF-05280014.

The study achieved the primary objective for equivalence in the objective response rate (ORR) of PF-05280014 compared with trastuzumab in patients with HER2-positive metastatic breast cancer administered first-line treatment in combination with paclitaxel.

Furthermore, rates of 1 year progression-free survival and 1 year survival were found to be similar across the treatment arms at 56% and 88.84% for PF-05280014 versus 52% and 87.96% for trastuzumab, respectively.

“Biosimilars are poised to revolutionize the oncology treatment landscape by expanding patient access to high quality and effective therapies,” Dr Mark Pegram, associate director for clinical research at the Stanford Comprehensive Cancer Institute, and direct of the Breast Oncology Program at the Stanford Women’s Caner Center, said in the release. “These data are encouraging, and reinforce the future potential of Pfizer’s investigational trastuzumab biosimilar to help meet the needs of cancer patients and their treating physicians as a potentially lower cost option to Herceptin, across all indications.”

Data from the REFLECTIONS B327-02 trial were presented at the European Society for Medical Oncology 2017 Congress in Madrid. Additionally, positive data from the supplemental study REFLECTIONS B327-04 were also presented.

In the REFLECTIONS B327-04, investigators found no clinically meaningfully differences between PF-05280014 and trastuzumab for safety, efficacy, immunogenicity, and non-inferiority in pharmacokinetics.

“Pfizer is committed to driving significant improvements in patient are through the development of high quality, effective biosimilars,” Salomon Azoulay, MD, senior vice president and chief medical officer of Pfizer Essential Health, said in the release. “By continuing to grow our oncology and supportive care presence through both novel therapies and biosimilars, we are able to provide an array of important treatment options for patients, physicians, and health care systems.”