Chinese biopharmaceutical company HUTCHMED has announced that the US Food and Drug Administration (FDA) has granted Orphan Drug Designation to sovleplenib for the treatment of primary immune thrombocytopenia (ITP), an autoimmune disorder associated with an increased risk of bleeding.
The FDA’s Orphan Drug Designation programme provides orphan status to drugs and biologics intended for the safe and effective treatment, diagnosis or prevention of rare diseases or conditions affecting fewer than 200,000 people in the US.
If approved for the designated indication, drugs receiving Orphan Drug Designation are eligible for seven years of US market exclusivity following approval, tax credits for qualifying clinical trials, waivers of certain user fees under the Prescription Drug User Fee Act and specialised regulatory guidance from the FDA during clinical development.
In China, New Drug Applications (NDAs) for sovleplenib for the treatment of primary ITP and warm antibody autoimmune haemolytic anaemia are currently under review by the National Medical Products Administration (NMPA).
The applications are supported by positive data from the pivotal ESLIM-01 and ESLIM-02 trials in China, respectively.
Understanding immune thrombocytopenia
As described by HUTCHMED, ITP is a rare autoimmune disorder characterised by the immune-mediated destruction of platelets and reduced platelet production. Patients with the condition face an increased risk of excessive bleeding and bruising. ITP is also associated with fatigue, reported in up to 39% of adults with the condition, and impaired quality of life.
Adult ITP can persist for years despite treatment, with few therapies offering a cure. Many patients develop treatment resistance or experience relapses, highlighting the need for new therapies for those who respond inadequately to existing treatments.
As platelet destruction in ITP is mediated by spleen tyrosine kinase (Syk)-dependent phagocytosis of platelets bound to Fc gamma receptors (FcγR), Syk inhibition represents a potential therapeutic approach for managing the condition.
Sovleplenib is a novel, selective Syk inhibitor designed for once-daily oral administration. Syk plays a key role in B-cell receptor and Fc receptor (FcR) signalling and is an established therapeutic target in multiple subtypes of B-cell lymphoma and autoimmune disorders.
HUTCHMED retains worldwide rights to sovleplenib.
