Takeda gets okay in US for rare blood disorder drug

Patients in the US with ultra-rare blood clotting disorder congenital thrombotic thrombocytopenic purpura (cTTP) have an FDA-approved therapy for the first time, after Takeda got the green light for its Adzynma drug.

cTTP is a subtype of thrombotic thrombocytopenic purpura (TTP), a rare and life-threatening disorder in which blood clots form in the small blood vessels throughout the body. It is caused by a deficiency in the ADAMTS13 protease enzyme.

Symptoms typically develop in infancy or early childhood, but in some cases may develop in adulthood and may first manifest during pregnancy. Patients with cTTP can experience severe bleeding episodes, strokes, and damage to vital organs, which can be fatal if untreated.

Adzynma (formerly TAK-755) is a recombinant form of ADAMTS13 that has been cleared for prevention, as well as on-demand treatment of children and adults with the disease, which is estimated to affect fewer than 1,000 patients with the disease in the US.

The drug is the first alternative to prophylactic plasma-based therapy used to indirectly replenish ADAMTS13 levels in the body. It is approved as an intravenous infusion once every week or every other week for prevention and as a once-daily infusion for on-demand treatment of acute events.

Plasma infusions take longer to administer and in acute cases continue until blood tests and symptoms improve, which can lead to days or even weeks in hospital. They can also lead to serious complications, including volume overload – when the amount of blood in the body gets too high and puts strain on the heart – as well as allergic reactions.

In a pivotal clinical trial, Adzynma reduced the incidence of low platelet count (thrombocytopenia) events by 60% compared to plasma-based treatment and was much better tolerated, with less than 9% of patients on Takeda's drug reporting side effects compared to almost half (48%) of those on standard therapy.

“Without treatment, cTTP is ultimately fatal,” said Peter Marks, director of the FDA’s Centre for Biologics Evaluation and Research (CBER). “Today’s approval reflects important progress in the development of much-needed treatment options for patients affected by this life-threatening disorder.”

Takeda said the launch of the drug will take place in December and, for now, it isn’t disclosing its pricing plans for the drug for cTTP. It does not expect the approval to have a material impact on its financial results in the current fiscal year ending 31st March 2024.

Meanwhile, the company is also running trials of the drug in other indications, including a phase 2 study in acquired or immune-mediated TTP (iTTP) and phase 1 in sickle cell disease (SCD), which if positive could expand the number of patients eligible for treatment.

Approval in iTTP would put Adzynma in competition with Sanofi's Cablivi (caplacizumab), which became the first therapeutic specifically indicated for the disease in the US in 2019. Sales of the drug were $169 million in the first nine months of the year, up around 15% on the same period of 2022.