Calliditas Therapeutics AB (STO:CALTX), a speciality pharmaceutical company, announced on Tuesday the grant by the US Food and Drug Administration (FDA) of orphan drug designation (ODD) to the company for the treatment of primary biliary cholangitis (PBC).

PBC, previously known as primary biliary cirrhosis, is an autoimmune disease of the liver, where common symptoms are tiredness, itching and, in more advanced cases, jaundice. PBC is a rare disease, affecting approximately 4.3 people in 10,000 in US.

Also, the company plans to discuss the regulatory pathway for this indication in consultation with the FDA and investigate the most appropriate way forward for this patient population.

Earlier in February 2019, the company was granted ODD by the FDA for AIH. The company plans to agree the regulatory pathway for this indication in consultation with the FDA later this year.

In addition, the company is currently running a global, pivotal phase 3 with study for the treatment of the rare disease IgA nephropathy (IgAN), which has already obtained ODD by the FDA and the European Medicines Agency (EMA). Top line data for IgAN is expected in H2 2020.

Calliditas Therapeutics is focused on developing high quality pharmaceutical products for patients with a significant unmet medical need in niche indications, in which the company can partially or completely participate in the commercialisation efforts.