A Study of TAK-662 for Japanese Patients With Congenital Protein C Deficiency

An Open-Label, Single-Dose, Phase 1/2 Study to Evaluate the Pharmacokinetics, Safety, and Tolerability of Human Protein C (TAK-662) for the Treatment of Congenital Protein C Deficiency in Japanese Subjects Followed by an Extension Part

Pharmacokinetic Part:

This study is for Japanese participants with congenital protein C deficiency. The main aim of this study is to check how much TAK-662 stays in their blood over time. This will help the study sponsor (Takeda) to work out the best dose to give patients in the future.

Participants will receive 1 single infusion of TAK-662.

They will stay at the clinic until 3 days after the infusion. Then, participants will return to their clinic 7 days after the infusion to check side effects from the study treatment.

Extension Part:

Participants who will complete the PK part will be given an opportunity to continue TAK-662 administration as 3 different treatment options (on-demand therapy, short-term prophylaxis, and long-term prophylaxis) in the Extension part, until the commercial protein C concentrate is available at each study site or study termination.

Inclusion Criteria:

PK Part:

1. Male and female participants with Japanese nationality.
2. A diagnosis of congenital protein C deficiency (homozygous or compound heterozygous).
3. Asymptomatic participant.
4. Oral anticoagulants allowed to be received.

Extension part:

1. Participants who participated in the PK part of this study (TAK-662-1501).
2. Participant who are; a. Diagnosed with PF, CISN/WISN, and/or other acute thromboembolic episode for on-demand treatment only; b. Requiring treatment with TAK-662 for short-term prophylaxis for surgical procedures; c. Requiring treatment with TAK-662 for long-term prophylaxis.

Exclusion Criteria:

PK Part:

1. Current or recurrent disease that could affect the action, or disposition of the investigational product (IP), or clinical or laboratory assessments.
2. A body weight less than 8 kg.
3. Serious liver dysfunction, judged by the investigator.
4. Any thrombosis within 2 weeks prior to administration of the IP.
5. Other investigational product than TAK-662 received within 60 days prior to the administration of the IP.
6. Current or relevant history of physical or psychiatric illness, or any medical disorder that may require treatment or make the participant unlikely to fully complete the study, or any condition that presents undue risk from the IP or procedures.
7. Current use of any medication (including over-the-counter, herbal, or homeopathic preparations) that could affect (improve or worsen) the condition being studied, or could affect the action or disposition of the IP, or clinical or laboratory assessment.
8. Known or suspected intolerance or hypersensitivity to the IP, closely-related compounds, or any of the stated ingredients.
9. Known history of alcohol or other substance abuse within the last year.
10. Within 30 days prior to the first dose of IP, a participant has been enrolled in a clinical study (including vaccine studies) that, in the investigator's opinion, may impact this sponsored study.

Extension Part:

1. New serious medical conditions which could affect participant's safety or treatment were observed during participation in the PK part of this study (TAK-662-1501).