Open-Label Extension Assessing Long Term Safety and Efficacy of IONIS-TTR Rx in Familial Amyloid Polyneuropathy (FAP)

Familial Amyloid Polyneuropathy (FAP) is a rare, hereditary disease caused by mutations in
the transthyretin (TTR) protein. TTR is made by the liver and secreted into the blood. TTR
mutations cause it to misfold and deposit in multiple organs causing FAP.

IONIS-TTR Rx is an antisense drug that is designed to decrease the amount of mutant and
normal TTR made by the liver. It is predicted that decreasing the amount of TTR protein will
result in a decrease in the formation of TTR deposits, and thus slow or stop disease
progression.

This study evaluates the safety and tolerability of extended dosing with IONIS-TTR Rx in
patients with Familial Amyloid Polyneuropathy.

Inclusion Criteria:

- Satisfactory completion of dosing & efficacy assessments in ISIS 420915-CS2

Exclusion Criteria:

- Any new condition or worsening of existing condition that could make the patient
unsuitable for participation, or interfere with the patient participating in and/or
completing the study