Inclusion Criteria:

1. Male or female participants ages 18-70 years old.
2. Diagnosis of aFXD associated with AL amyloidosis with FX:C ≤ 50 IU/dL.
3. Woman of Childbearing Potential (defined in Appendix 2) and men of reproductive potential who agree to use an effective contraception measure during the study.

Exclusion Criteria:

1. Female participants that are pregnant or lactating.
2. Presence of FX inhibitors.
3. Uncontrolled arterial hypertension.
4. On anticoagulant therapy (not antiplatelets), unstable heart disease, clinically significant thrombotic event in the past 180 days or any other condition that the Investigator believes is likely to interfere with evaluation of the study drug or with satisfactory conduct of the trial.
5. Any factor X containing product taken within 2 weeks of first Coagadex® administration.
6. Participation in another interventional clinical study with an investigational drug, biologic, or device within 30 days prior to screening.
7. Hemodynamically unstable due to any cause or even after blood transfusion, fluid resuscitation and pharmacologic or volume replacement pressor therapy.
8. Prior history of bleeding disorder other than aFXD.

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 11/12/2025. Questions regarding updates should be directed to the study team contact.