Dyax is engaged in the development and commercialization of novel biotherapeutics for unmet medical needs.
The company is developing DX-2930, a fully humanized monoclonal antibody targeting plasma kallikrein (pKal) inhibitors to treat hereditary angioedema (HAE).
Dyax also markets Kalbitor (ecallantide) to treat acute attacks of HAE in patients 12 years of age and older.
Shire paid $37.30 for each Dyax share. Dyax investors may also get an additional $4.00 per share in cash via a non-tradable contingent value right for the regulatory approval of phase 3-stage DX-2930, representing a potential additional $646m in aggregate contingent consideration.
Shire CEO Flemming Ornskov said: "The addition of Kalbitor and DX-2930 to our portfolio strengthens our leadership position in HAE and, along with the commercial and research and development expertise at Dyax, is a clear strategic fit for us that advances our position as the global leader in rare diseases."
DX-2930 recently completed early-stage clinical trials, which showed it reduced attacks by over 90% in patients who had suffered from two or more flare-ups in the previous three months.
It is expected to be launched in 2018 and bring in about $2bn in peak annual sales.
Shire expects the deal to generate about $50m in savings in 2017 and $100m in 2019.