Safety And Efficacy Evaluation Of Fx-1006A In Subjects With Transthyretin Amyloidosis

This is a Phase 3, open-label study designed to obtain additional, long-term, open-label safety and efficacy data for Fx-1006A and to continue to provide patients with 20 mg oral Fx-1006A (soft gel capsule) who have completed either Protocol Fx-006 (a 1 year, open-label extension study to Protocol Fx-005 which is a randomized, double-blind, placebo-controlled, 18-month study to evaluate the safety and efficacy of Fx-1006A) or Protocol Fx1A-201 (a Phase 2, open-label study to evaluate TTR stabilization as well as the safety and tolerability of Fx-1006A) until market availability of Fx-1006A in individual patients' country of residence.

Patients who successfully complete Protocol Fx-006 or Fx1A-201 will report to the clinical unit on Day 0 (Baseline) to sign the informed consent form and determine their eligibility for Protocol Fx1A-303. In addition, on Day 0 (Baseline), patients will have their entrance criteria reviewed and medical history and demography for all patients will be obtained. The relevant end of study assessments from Protocols Fx1A-201 and Fx-006 will serve as Baseline assessments for Protocol Fx1A-303 if these examinations were performed within 30 days of Day 0 (Baseline). For any patient successfully completing Protocol Fx-006, the Karnofsky Performance Scale Index will be assessed and the cranial nerve and upper limb components of the NIS will be performed and combined with the NIS-LL data from the end of study visit from Protocol Fx-006.

If there is more than 30 days between the final study visit of Fx-006 or Fx1A-201 and Day 0 (Baseline) of Fx1A-303, all Day 0 study procedures will be performed (i.e., no data from the final study visits from the previous studies will be utilized).

Eligible patients will begin once-daily dosing with 20 mg Fx-1006A at home on Day 1 (i.e., first dose) and will return to the clinical unit for study visits every 6 months.

Adverse events (AEs) and concomitant medication use will be collected at each 6-month visit to the clinical unit and, if female, a urine pregnancy test will be performed. An abbreviated physical examination (including weight and vitals signs) will be conducted at every other 6 month visit. A telephone call will be made at 3-month intervals between clinic visits to assess safety and the use of concomitant medications.

For the evaluation of efficacy, the NIS, Norfolk QOL-DN, and Karnofsky Performance Scale Index will be performed on an annual basis (i.e., every other 6-month visit).

An end of study visit will occur upon patient withdrawal (for any reason), program discontinuation by the Sponsor, or upon market availability of Fx-1006A in individual patients' country of residence.

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Inclusion Criteria:

• Patient has successfully completed either Protocol Fx-006 or Fx1A-201.
• If female, patient is post-menopausal, surgically sterilized, or willing to use two acceptable methods of birth control (i.e., hormonal contraceptive, intra-uterine device, diaphragm with spermicide, condom with spermicide) throughout the study and for 3 months from the end of the study. (A condom alone is not considered an acceptable method of birth control.)
• Patient is, in the opinion of the investigator, willing and able to comply with the investigational product regimen and all other study requirements.

Exclusion Criteria:

• Patient has not successfully completed either Protocol Fx-006 or Fx1A-201.
• Chronic use of non-protocol approved non-steroidal anti-inflammatory drugs (NSAIDs), defined as greater than 3 to 4 times/month. The following NSAIDs are allowed: acetylsalicylic acid, etodolac, ibuprofen, indomethicin, ketoprofen, nabumetone, naproxen, nimesulide, piroxicam, and sulindac.
• If female, patient is pregnant or breast feeding.
• Clinically significant medical condition that, in the opinion of the investigator, would place the patient at an increased risk to participate in the study.
• The patient has received a liver or heart transplant prior to enrollment.