Pfizer is set to pay $340 million (€304 million) upfront to buy Therachon for its treatment for a form of short-limbed dwarfism. The deal commits Pfizer to up to $470 million in additional milestones tied to the advance of the early-phase rare disease drug.
Therachon has emerged as one of the better financed European rare disease biotechs in recent years, pulling in $100 million from investors including Novo Holdings and OrbiMed across its series A and B rounds. The funding has supported work on TA-46, a FGFR3 ligand trap designed to prevent the excessive signalling thought to suppress bone growth in people with achondroplasia.
Limited data are available publicly on the drug, which only began testing in healthy volunteers last year. But Pfizer has seen enough promise in the preclinical and phase 1 results to put together an $810 million financial package and make TA-46 a key part of its plans in pediatric growth disorders.
“Pfizer’s existing research programs for pediatric growth disorders provide a complementary setting for this potential breakthrough therapy,” Pfizer Senior Vice President Seng Cheng said in a statement.
Patients with achondroplasia currently lack pharmacological treatment options, but Therachon is far from the only company trying to address the unmet need. BioMarin’s vosoritide moved into phase 3 in 2017, and a small pool of other companies including Denmark’s Ascendis Pharma are also going after the indication. Ascendis thinks the global achondroplasia market could exceed $1 billion.
Therachon’s pipeline also features a synthetic GLP-2 analog that it picked up in its 2018 takeover of GLyPharma Therapeutic. That drug is in phase 2 development in short bowel syndrome but holds less appeal to Pfizer, leading the Big Pharma to clear Therachon to spin it off to form a new startup. Pfizer Ventures will hold a stake in the startup, but the new company will advance the asset independently.