Takeda Pharmaceutical Company Limited announced that the totality of evidence from a pre-planned interim analysis of a pivotal Phase 3 study supports the efficacy and safety of TAK-755 as enzyme replacement therapy for congenital thrombotic thrombocytopenic purpura (cTTP). cTTP is an ultra-rare sub-type of thrombotic thrombocytopenic purpura (TTP), a rare, chronic and debilitating blood clotting disorder caused by a deficiency in ADAMTS13 protease. Acute TTP has a mortality rate of >90%, if left untreated. The trial was designed to evaluate the clinical benefit of TAK-755 across multiple clinically relevant endpoints and based on the totality of the evidence provided by efficacy, pharmacokinetic, safety and tolerability data.

This approach was discussed with global regulatory agencies. The study evaluated TAK-755 compared to plasma-based therapies, which are the current standard of care (SoC), in a randomized cross-over study. The interim results showed that TAK-755 reduced the incidence of thrombocytopenia events by 60% (95% Confidence Interval, 30%-70%), an important marker of disease activity in cTTP, as compared to SoC.

The proportion of subjects experiencing adverse events determined to be related to the treatment was substantially lower among subjects during treatment with TAK-755 (8.9%) compared to that while receiving SoC therapy (47.7%). Based on these data from the Phase 3 interim analysis, Takeda aims to seek marketing authorization for TAK-755 as the first recombinant ADAMTS13 (rADAMTS13) replacement therapy for cTTP, a disorder with considerable unmet patient need. Takeda plans to submit the results of this interim analysis for presentation at an upcoming scientific meeting.

In addition to announcing these results, Takeda indicated that the December 22, 2022, edition of the New England Journal of Medicine (NEJM) included two case reports written and submitted by two physicians who requested compassionate use of TAK-755 to treat patients who were facing critical health complications related to cTTP. The case reports are available on NEJM's website. TAK-755 is also being investigated in a Phase 2 study to evaluate the pharmacokinetics, safety and efficacy of rADAMTS13 in immune-mediated TTP (iTTP).

Results from the interim analysis of the Phase 3 study have no impact on the full year consolidated reported forecast for the fiscal year ending March 31, 2023 (Fiscal Year 2022).