US-based immunotherapy developer Harpoon Therapeutics has filed to raise up to $86.3m in an initial public offering that would enable pharmaceutical companies Eli Lilly and Taiho to exit.
Harpoon is working on T cell engagers intended to treat diseases such as cancer by leveraging the body’s immune system, and aims to have advanced four drug candidates into clinical testing by the end of 2020.
The IPO proceeds will support clinical work on HPN424, a candidate that is in a phase 1 trial for metastatic castration-resistant prostate cancer, and a second candidate, HPN536, which is expected to shortly begin testing for ovarian cancer and solid tumours expressing the mesothelin antigen.
Harpoon has raised at least $115m in funding, most recently securing $70m in a series C round featuring corporate venturing units Lilly Asia Ventures and Taiho Ventures last month.
Healthcare-focused investment firm OrbiMed led the round, which included Arix Bioscience, Cormorant Asset Management, NS Investment, MPM Capital, Oncology Impact Fund, Ridgeback Capital Investments and New Leaf Venture Partners.
Arix and New Leaf had co-led the company’s $45m series B round in May 2017, investing alongside Taiho Ventures and MPM Capital, the latter of which had previously supplied an undisclosed amount of series A cash for Harpoon.
Neither corporate holds 5% or more of Harpoon’s shares. Its largest shareholders are MPM Capital (23.3%) and UBS Oncology Impact Fund, a vehicle for which MPM is general partner (20.2%), followed by New Leaf (13.9%), Arix (13.7%) and OrbiMed (11.6%).
Citigroup and Leerink Partners have been appointed joint book-running managers for the IPO, which will take place on the Nasdaq Stock Market, while Canaccord Genuity and Wedbush PacGrow are co-managers.
