Yesterday, the FDA approved Roche’s ado-trastuzumab emtansine (Kadcyla) for the adjuvant treatment of HER2-positive early breast cancer in patients who have residual invasive disease after neoadjuvant taxane- and trastuzumab-based therapy. The new indication could help to stave off some of the impact of biosimilar trastuzumab, which is expected to launch this year.
Yesterday, the FDA approved Roche’s ado-trastuzumab emtansine (Kadcyla) for the adjuvant treatment of HER2-positive early breast cancer in patients who have residual invasive disease after neoadjuvant taxane- and trastuzumab-based therapy.
The approval of the drug was based on the phase 3 KATHERINE study, a randomized, open-label trial in 1486 patients with HER2-positive EBC.1 Patients received either ado-trastuzumab emtansine or Roche’s trastuzumab (Herceptin), and the study’s primary end point was invasive disease-free survival. After a median follow-up of 40 months, the trial demonstrated a statistically significant improvement in the primary end point in patients who received ado-trastuzumab emtansine compared with those who received trastuzumab (hazard ratio for invasive disease or death, 0.50; 95% CI, 0.39-0.64; P <.0001), and safety data were consistent with the known profile of the study drug.
Ado-trastuzumab emtansine was first approved in the United States in 2013 for the treatment of HER2-positive metastatic breast cancer, and is a so-called “biobetter” of Roche’s older trastuzumab. The product is an antibody—drug conjugate (ADC), comprising the monoclonal antibody trastuzumab with maytansinoid DM1. Trastuzumab binds to HER2 on the tumor cell surface, and on internalization, the DM1 moiety inhibits cell division and the proliferation of cancer cells, providing a therapeutic advantage over trastuzumab alone.
Because there is no regulatory pathway specifically devised to address “biobetters,” and the term is typically used in marketing rather than in a scientific context, these products have the substantial business benefit of being treated as new agents. Altering an originator biologic will result in a therapy that must be addressed as a new product under existing regulatory pathways, and approval may lead to patent protection and market exclusivity that can help defend a company’s market share against biosimilar competition for originator products that have lost—or are about to lose—patent protection.2
Biosimilars of trastuzumab have already entered the European market and have begun to make an impact on Roche’s sales; Roche recently revealed that its sales for the innovator drug declined by 44% in the first quarter of this year. However, to date, the brand-name Herceptin, still top-selling drug for Roche, has no US biosimilar competition.
That is set to change, however, as 4 biosimilars (Ogivri, Herzuma, Ontruzant, and Trazimera) have been FDA approved, and Roche predicted in a 2018 earnings call that it would face its first biosimilar trastuzumab competition in the US market in the second half of 2019. Roche’s new indication for its biobetter could help to stave off some of the impact of those biosimilar launches, given the ADC’s advantages over trastuzumab.
Reference
1. von Minckwitz G, Huang CS, Mano MS, et al. Trastuzumab emtasine for residual invasive HER2-positive breast cancer. NEJM. 2019;380:617-628. doi: 10.1056/NEJMoa1814017.
2. Kesik-Brodacka M. Progress in biopharmaceutical development. Biotechnol Appl Biochem. 2018;65(3):306-322. doi: 10.1002/bab.1617.
Eye on Pharma: Sandoz Files Antitrust Suit; Yuflyma Interchangeability; Costco’s Ustekinumab Pick
April 22nd 2025Sandoz's antitrust suit against Amgen, the FDA’s interchangeability designation for Celltrion’s adalimumab biosimilar, and the inclusion of an ustekinumab biosimilar in Costco’s prescription program highlight growing momentum to expand biosimilar access and affordability for patients with chronic inflammatory diseases.
How AI Can Help Address Cost-Related Nonadherence to Biologic, Biosimilar Treatment
March 9th 2025Despite saving billions, biosimilars still account for only a small share of the biologics market—what's standing in the way of broader adoption and how can artificial intelligence (AI) help change that?
Will the FTC Be More PBM-Friendly Under a Second Trump Administration?
February 23rd 2025On this episode of Not So Different, we explore the Federal Trade Commission’s (FTC) second interim report on pharmacy benefit managers (PBMs) with Joe Wisniewski from Turquoise Health, discussing key issues like preferential reimbursement, drug pricing transparency, biosimilars, shifting regulations, and how a second Trump administration could reshape PBM practices.
How State Substitution Laws Shape Insulin Biosimilar Adoption
April 15th 2025States with fewer restrictions on biosimilar substitution tend to see higher uptake of interchangeable insulin glargine, showing how even small policy details can significantly influence biosimilar adoption and expand access to more affordable insulin.
Latest Biosimilar Deals Signal Growth Across Immunology, Oncology Markets
April 14th 2025During Q1 2025, pharmaceutical companies accelerated biosimilar expansion through strategic acquisitions and partnerships in hopes of boosting patient access to lower-cost treatments in immunology and oncology.