Pfizer has agreed to acquire Therachon Holdings for up to $810 million, the companies said today, in a deal intended to expand the buyer’s rare disease portfolio with a pipeline to be led by a clinical-phase candidate for the most common form of short-limbed dwarfism.
Therachon’s TA-46 is a soluble recombinant human fibroblast growth factor receptor 3 (FGFR3) decoy for children and adolescents with achondroplasia. TA-46—which has completed Phase I study—has received orphan drug designations from the FDA and European Medicines Agency.
“By acquiring Therachon, we hope to leverage Pfizer’s leading scientific and development capabilities to more rapidly advance this potentially promising therapy for people with achondroplasia,” Mikael Dolsten, Pfizer CSO and president, worldwide research, development, and medical, said in a statement.
There are currently no approved treatments for achondroplasia, a genetic condition that can lead to serious cardiovascular, neurological, and metabolic complications for approximately 250,000 people worldwide.
“With its rare disease expertise and worldwide reach, Pfizer is well positioned to accelerate the development of TA-46 and fulfill Therachon’s vision of addressing the complications suffered by children with achondroplasia by targeting the molecular root causes of this condition,” added Therachon CEO Luca Santarelli.
“We are thrilled that the work we have done to discover and advance a novel and potentially life-transforming medicine for achondroplasia is now being continued by Pfizer,” Santarelli added.
Privately-held Therachon is based in Basel, Switzerland. Pfizer agreed to acquire Therachon for $340 million upfront, and up to an additional $470 million tied to achieving development and commercialization milestones for TA-46.
Taking aim at BioMarin
By developing TA-46, Pfizer would position itself as a direct competitor to BioMarin Pharmaceutical, which is developing the Phase III candidate Vosorotide (BMN 111) for achondroplasia.
In 2015, BioMarin announced positive Phase II proof-of-concept results for vosoritide, an analog of CNP which is designed to bind to a specific receptor that initiates intracellular signals that inhibit the overactive FGFR3 pathway.
Vosorotide is the subject of numerous clinical studies, including two Phase III trials: NCT03197766, which was active but not recruiting patient as of May 7; and NCT03424018 , which was enrolling by invitation as of the most recent update posted July 30, 2018.
TA-46 is not furthest along in Therachon’s current pipeline. That distinction belongs to apraglutide, a once-weekly, potential best-in-class GLP-2 analog that is in Phase II development for short bowel syndrome, and in Phase I for other rare gastrointestinal diseases.
However, before it closes its deal to be acquired by Pfizer, Therachon plans to spin off its apraglutide development program into a separate, independent company. Pfizer’s venture capital arm Pfizer Ventures, which now holds a minority stake in Therachon, will hold an equity stake in the new company.
Pfizer is holding on to another Therachon pipeline candidate, TA-100, an FGFR3 decoy also indicated for achondroplasia and other rare skeletal dysplasias.
Pfizer Ventures was among new investors that took part in Therachon’s $60 million mezzanine financing in August 2018. The financing was led by Novo Holdings with Pfizer Ventures among new investors that included Cowen Healthcare Investments and funds managed by Tekla Capital Management. Existing investors Versant Ventures, OrbiMed, Bpifrance, and Inserm Transfert Initiative also participated.
According to Crunchbase, Therachon has raised a total $100 million in financing since it was founded in 2014.