The Swedish firm has decided to pass on a bid from a proposed buyer which would have involved a healthy premium but “considerably undervalued” its long-term prospects.

Data from part B of the Swedish firm’s pivotal trial of Tarpeyo in the rare kidney disorder showed that the treatment effects lasted two years across the entire population, enabling the move from conditional to full approvals in several markets.

The Swedish group’s Tarpeyo is reaping the benefits of an expanded US sales force and the company is confident of a big revenue rise in 2023, regardless of new competition in the IgAN field from Travere’s Filspari.

Travere Therapeutics is aiming to provide a new foundational therapy for IgAN patients with its novel non-immunosuppressive agent, Filspari, as it prices it at a discount to Calliditas’s rival Tarpeyo, ahead of looming further competition.