The funding round resulted in resulted in a write-up of Arix’s initial investment in Harpoon to £14.1mln, a £4.7mln uplift to the most recent valuation of £9.4mln.
Including the £6.1mln Series C investment, the value of Arix’s 11.3% stake in Harpoon has increased to £20.2mln.
Arix investment director Mark Chin will continue to serve on Harpoon’s board of directors.
Harpoon will use the proceeds from the financing to support further advancement of its immunotherapy programs based on its TriTAC and ProTriTAC platforms, which are designed to harness the natural power of the body’s immune system to fight cancer and other diseases.
Its lead candidate, HPN224, is currently in phase I clinical trial as a potential treatment for prostate cancer.
Harpoon also plans to initiate a phase I clinical trials in for HPN536 for the treatment of mesothelin-expressing tumours, and HPN217 for the treatment of multiple myeloma, in 2019.
On top of that, Harpoon expects to advance its first ProTriTAC product candidate into IND-enabling studies in 2019.