Eplontersen

12.1 Mechanism of Action Eplontersen is an antisense oligonucleotide-GalNAc conjugate that causes degradation of mutant and wild-type TTR mRNA through binding to the TTR mRNA, which results in a reduction of serum TTR protein and TTR protein deposits in tissues.

1 INDICATIONS AND USAGE WAINUA is indicated for the treatment of the polyneuropathy of hereditary transthyretin-mediated amyloidosis in adults. WAINUA is a transthyretin-directed antisense oligonucleotide indicated for the treatment of the polyneuropathy of hereditary transthyretin-mediated amyloidosis in adults. ( 1 )

2 DOSAGE AND ADMINISTRATION • The recommended dosage of WAINUA is 45 mg administered by subcutaneous injection once monthly. ( 2.1 ) • Administer WAINUA into the abdomen or upper thigh region; the back of the upper arm can be used if a healthcare provider or caregiver administers the injection. ( 2.2 ) 2.1 Recommended Dosage The recommended dosage of WAINUA is 45 mg administered by subcutaneous injection once monthly [see Dosage and Administration (2.2) ] . Missed Dose Administer WAINUA as soon as possible after a missed dose. Resume dosing at monthly intervals from the date of the most recently administered dose. 2.2 Administration Instructions Prior to initiation, train patients and/or caregivers on proper preparation and administration of WAINUA [see Instructions for Use ] . Remove the single-dose autoinjector from the refrigerator 30 minutes prior to the injection and allow to warm to room temperature. Do not use other warming methods. Inspect WAINUA visually for particulate matter and discoloration prior to administration. The solution should appear colorless to yellow. Do not use if cloudiness, particulate matter, or discoloration is observed prior to administration. Administer WAINUA as a subcutaneous injection into the abdomen or upper thigh region. The back of the upper arm can also be used as an injection site if a healthcare provider or caregiver administers the injection.

6 ADVERSE REACTIONS The following clinically significant adverse reactions are discussed in greater detail in other sections of the labeling: • Reduced Serum Vitamin A Levels and Recommended Supplementation [see Warnings and Precautions (5.1) ]. Most common adverse reactions (that occurred in at least 9% of patients treated with WAINUA) were vitamin A decreased and vomiting. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact AstraZeneca at 1-800-236-9933 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of WAINUA cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. In Study 1 [see Clinical Studies (14) ] , a total of 144 patients with polyneuropathy caused by hereditary transthyretin-mediated amyloidosis (hATTR amyloidosis) were randomized to WAINUA and received at least one dose of WAINUA. Of these, 141 patients received at least 6 months of treatment and 107 patients received at least 12 months of treatment. The mean duration of treatment was 15 months (range: 1.9 to 19.4 months). The median patient age at baseline was 52 years and 69% of the patients were male. Seventy-eight percent of patients treated with WAINUA were White, 15% were Asian, 4% were Black, 2% were reported as other races, and <1% were multiple races. Fifty-nine percent of patients had the Val30Met variant in the transthyretin gene; the remaining patients had one of 19 other variants. At baseline, 80% of patients were in Stage 1 of the disease and 20% were in Stage 2 with a mean duration from polyneuropathy diagnosis of 47 months. The mean duration from onset of polyneuropathy symptoms was 68 months. Table 1 lists the adverse reactions that occurred in at least 5% of patients treated with WAINUA in Study 1. Table 1: Adverse Reactions Reported in at least 5% of Patients Treated with WAINUA (Study 1) Adverse Reaction WAINUA N=144 % Vitamin A decreased Vitamin A decreased includes vitamin A deficiency and vitamin A decrease. 15 Vomiting 9 Proteinuria 8 Injection site reactions Injection site reactions includes erythema, pain, and pruritis. 7 Blurred vision 6 Cataract 6 Three serious adverse reactions of atrioventricular (AV) heart block (2%) occurred in WAINUA-treated patients, including 1 case of complete AV block. Laboratory Tests Vitamin A Decrease In Study 1, patients were instructed to take the recommended daily allowance of vitamin A [see Warnings and Precautions (5.1) ] . All patients treated with WAINUA had normal vitamin A levels at baseline, 95% of patients developed low vitamin A levels during the study. In some cases, the decreased vitamin A level was reported as an adverse reaction.