Sobi has shared positive results from a late-stage study of Doptelet (avatrombopag) in paediatric patients with immune thrombocytopenia (ITP), a rare autoimmune disorder estimated to affect up to 100 people per million.
The condition, characterised by low numbers of platelets that lead to bruising and an increased risk of bleeding, occurs in five out of 100,000 children per year. There is currently no cure available and patients usually relapse after various treatments, yet they still require treatment to reduce the risk of clinically significant bleeding.
Sobi’s Doptelet, an orally administered thrombopoietin receptor agonist that works to increase platelet count, is already approved in the US and EU to treat certain adults with chronic ITP.
It is hoped that data from the phase 3 AVA-PED-301 study, which has been evaluating Doptelet against placebo in eligible children and adolescents with ITP, will support global regulatory filings for the use of the therapy in this patient population.
Lydia Abad-Franch, head of research, development and medical affairs, and chief medical officer at Sobi, said: “Considering the challenges in treatment administration, coupled with variable and transient responses, frequent relapses and associated toxicities from existing therapies, an unmet medical need currently exists in managing ITP among children and adolescents.”
AVA-PED-301’s primary endpoint of durable platelet response was met in 28% of Doptelet-treated patients in comparison to 0% of those in the placebo cohort. The key secondary endpoint of two consecutive platelet counts was also met in 81.5% of patients receiving Doptelet, compared with 0% in the placebo arm.
Additionally, a platelet response at day eight was observed in 56% of Doptelet-treated patients and 0% of those receiving placebo, while rescue therapy use occurred in 7% of the Doptelet group and 43% of the placebo group.
Rachael Grace, lead investigator of the study, said: “Based on these results, I believe that [Doptelet] could provide a much-needed oral treatment option for adolescents and children with persistent and chronic ITP.
“In this paediatric population, the lack of any food restrictions or chronic immune suppression with [Doptelet] treatment would be beneficial for patients living with ITP.”
Beyond ITP, Doptelet holds approvals to treat thrombocytopenia in certain adults with chronic liver disease who are scheduled to undergo a procedure.
