HLX319

**HLX319** is Shanghai Henlius Biotech's investigational fixed-dose **subcutaneous biosimilar of Phesgo** containing the anti-HER2 monoclonal antibodies **pertuzumab** and **trastuzumab**, with proprietary recombinant human hyaluronidase as a formulation excipient to facilitate subcutaneous delivery. The complementary HER2-directed antibodies inhibit HER2 signaling: pertuzumab disrupts HER2 dimerization and trastuzumab inhibits HER2-mediated tumor signaling. HLX319 is being evaluated for HER2-positive breast cancer, including neoadjuvant treatment of early or locally advanced disease; Henlius has also stated intended development in adjuvant and metastatic settings. ([henlius.com](https://www.henlius.com/en/NewsDetails-5835-26.html))

Other names

pertuzumab + trastuzumab