FDA Label for Wainua

1 Indications And Usage

WAINUA is indicated for the treatment of the polyneuropathy of hereditary transthyretin-mediated amyloidosis in adults.

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.

3 Dosage Forms And Strengths

Injection: 45 mg/0.8 mL of eplontersen as a clear, colorless-to-yellow solution in a single-dose autoinjector.

4 Contraindications

None.

5.1 Reduced Serum Vitamin A Levels And Recommended Supplementation

WAINUA treatment leads to a decrease in serum vitamin A levels [see Adverse Reactions (6.1), Use in Specific Populations (8.1), and Clinical Pharmacology (12.2)].

Supplementation at the recommended daily allowance of vitamin A is advised for patients taking WAINUA. Higher doses than the recommended daily allowance of vitamin A should not be given to try to achieve normal serum vitamin A levels during treatment with WAINUA, as serum vitamin A levels do not reflect the total vitamin A in the body.

Patients should be referred to an ophthalmologist if they develop ocular symptoms suggestive of vitamin A deficiency (e.g., night blindness, dry eyes).

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)]

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.

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.

Risk Summary

There are no available data on WAINUA use in pregnant women to inform drug-associated risk of adverse developmental outcomes. WAINUA treatment leads to a decrease in serum vitamin A levels, and vitamin A supplementation is advised for patients taking WAINUA. Vitamin A is essential for normal embryofetal development; however, excessive levels of vitamin A are associated with adverse developmental effects. The effect of vitamin A supplementation on the fetus in the setting of a reduction in maternal serum TTR caused by WAINUA administration is unknown [see Clinical Pharmacology (12.2) and Warnings and Precautions (5.1)].

No adverse developmental effects were observed when eplontersen or a mouse-specific surrogate was administered to mice prior to mating and continuing throughout organogenesis [see Animal Data].

In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown.

There is no information regarding the presence of eplontersen in human milk, the effects on the breast-fed infant, or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for WAINUA and any potential adverse effects on the breast-fed infant from WAINUA or from the underlying maternal condition.

Animal Data

Subcutaneous administration of eplontersen (0, 5, 25, or 75 mg/kg) or a mouse-specific surrogate (25 mg/kg) to male and female mice weekly prior to and during mating and administration continued every other day in females throughout the period of organogenesis resulted in no adverse effects on embryofetal development.

8.4 Pediatric Use

Safety and effectiveness in pediatric patients have not been established.

8.5 Geriatric Use

No dose adjustment is required in patients ≥65 years of age [see Clinical Pharmacology (12.3)]. In Study 1 [see Clinical Studies (14)], 44 (31%) patients were 65 to 74 years of age, and 8 (5.6%) patients were ≥75 years of age. No overall differences in safety or effectiveness were observed between these patients and younger adult patients, but greater sensitivity of some older individuals cannot be ruled out.

8.6 Renal Impairment

No dose adjustment is necessary in patients with mild to moderate renal impairment (estimated glomerular filtration rate [eGFR]≥30 to <90 mL/min/1.73 m²) [see Clinical Pharmacology (12.3)].

WAINUA has not been studied in patients with severe renal impairment or end-stage renal disease.

8.7 Hepatic Impairment

No dose adjustment is necessary in patients with mild hepatic impairment (total bilirubin ≤1 x ULN and AST >1 x ULN, or total bilirubin >1.0 to 1.5 x ULN and any AST) [see Clinical Pharmacology (12.3)].

WAINUA has not been studied in patients with moderate or severe hepatic impairment.

11 Description

Eplontersen is a transthyretin-directed antisense oligonucleotide (ASO), covalently linked to a ligand containing three N-acetyl galactosamine (GalNAc) residues to enable delivery of the ASO to hepatocytes.

WAINUA contains eplontersen sodium as the active ingredient. Eplontersen sodium is a white to yellow solid and it is freely soluble in water and in phosphate buffer. The molecular formula of eplontersen sodium is C₂₉₆H₄₁₇N₇₇O₁₅₆P₂₀S₁₃Na₂₀ and the molecular weight is 9046.1 daltons. The chemical name of eplontersen sodium is DNA, d([2′-O-(2-methoxyethyl)]m5rU-sp-[2′-O-(2-methoxyethyl)]m5rC-[2′-O-(2-methoxyethyl)]m5rU-[2′-O-(2-methoxyethyl)]m5rU-[2′-O-(2-methoxyethyl)]rG-G-sp-T-sp-T-sp-A-sp-m5C-sp-A-sp-T-sp-G-sp-A-sp-A-sp-[2′-O-(2-methoxyethyl)]rA-[2′-O-(2-methoxyethyl)]m5rU-[2′-O-(2-methoxyethyl)]m5rC-sp-[2′-O-(2-methoxyethyl)]m5rC-sp-[2′-O-(2-methoxyethyl)]m5rC), 5′-[26-[[2-(acetylamino)-2-deoxy-β-D-galactopyranosyl]oxy]-14,14-bis[[3-[[6-[[2-(acetylamino)-2-deoxy-β-D-galactopyranosyl]oxy]hexyl]amino]-3-oxopropoxy]methyl]-8,12,19-trioxo-16-oxa-7,13,20-triazahexacos-1-yl hydrogen phosphate], sodium salt (1:20).

The structure of eplontersen sodium is presented below:

Chemical_Structure - chemical structure

WAINUA is a sterile, preservative-free, aqueous solution for subcutaneous injection. Each single-dose autoinjector contains 45 mg eplontersen (equivalent to 47 mg eplontersen sodium) in 0.8 mL of solution. The solution also contains dibasic sodium phosphate, anhydrous (to adjust pH); monobasic sodium phosphate, dihydrate (to adjust pH); sodium chloride (to adjust tonicity); water for injection; and may include hydrochloric acid and/or sodium hydroxide for pH adjustment between 6.9 – 7.9. Each dose of WAINUA injection contains 5 mg of sodium and 5 mg of phosphorus.

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.

12.2 Pharmacodynamics

In Study 1 [see Clinical Studies (14)], following administration of the recommended WAINUA dosage every 4 weeks to patients with hATTR amyloidosis, a decrease in serum TTR levels was observed at the first assessment and the (least square) mean serum TTR at Week 35 was reduced by 81% from baseline. Similar TTR reductions were observed across subgroups including Val30Met variant status, body weight, sex, age, or race.

Eplontersen also reduced the mean steady state serum vitamin A by 71% by Week 37 [see Warnings and Precautions (5.1)].

Cardiac Electrophysiology

At a dose 2.7-times the maximum recommended dose for WAINUA, clinically significant QTc interval prolongation was not observed.

12.3 Pharmacokinetics

The pharmacokinetic (PK) properties of WAINUA were evaluated following subcutaneous administration of single and multiple doses (once every 4 weeks) in healthy subjects and multiple doses (once every 4 weeks) in patients with hATTR amyloidosis.

Eplontersen C_max and AUC showed a slightly greater than dose-proportional increase following single subcutaneous doses ranging from 45 to 120 mg (i.e., 1- to 2.7-times the recommended dose) in healthy volunteers.

Population estimates (mean ± SD) of steady state maximum concentrations (C_max), and area under the curve (AUC_τ) were 283 ± 152 ng/mL, and 2190 ± 689 ng/mL, respectively, following 45 mg monthly dosing in patients with hATTR amyloidosis. No accumulation of eplontersen C_max and AUC was observed in repeated dosing (once every 4 weeks).

Absorption

Following subcutaneous administration, eplontersen is absorbed with the time to maximum plasma concentrations of approximately 2 hours, based on population estimates.

Distribution

Eplontersen is expected to distribute primarily to the liver and kidney cortex after subcutaneous dosing. Eplontersen is bound to human plasma proteins (>98%) in vitro. The population estimate for the apparent central volume of distribution is 12 L and the apparent peripheral volume of distribution is 11,100 L.

Elimination

The terminal elimination half-life is approximately 3 weeks.

Metabolism

Eplontersen is metabolized by endo- and exonucleases to short oligonucleotide fragments of varying sizes within the liver.

Excretion

The mean fraction of unchanged ASO eliminated in urine was less than 1% of the administered dose within 24 hours.

Specific Populations

Population pharmacokinetic and pharmacodynamic analysis showed no clinically meaningful differences in the pharmacokinetics or pharmacodynamics of eplontersen based on age, body weight, sex, race, Val30Met variant status, mild and moderate renal impairment (eGFR ≥30 to <90 mL/min), or mild hepatic impairment (total bilirubin ≤1 x ULN and AST >1 x ULN, or total bilirubin >1.0 to 1.5 x ULN and any AST). Eplontersen has not been studied in patients with severe renal impairment, end-stage renal disease, or in patients with moderate to severe hepatic impairment, or in patients with prior liver transplant.

Drug Interaction Studies

No clinical drug-drug interaction studies have been performed with eplontersen. In vitro studies show that eplontersen is not a substrate or inhibitor of transporters, does not interact with highly plasma protein bound drugs, and is not an inhibitor or inducer of cytochrome P450 (CYP) enzymes. Oligonucleotide therapeutics, including eplontersen, are not typically substrates of CYP enzymes. Therefore, eplontersen is not expected to cause or be affected by drug-drug interactions mediated through drug transporters, plasma protein binding or CYP enzymes.

12.6 Immunogenicity

The observed incidence of anti-drug antibodies (ADAs) is highly dependent on the sensitivity and specificity of the assay. Differences in assay methods preclude meaningful comparisons of the incidence of ADAs in the study described below with the incidence of anti-drug antibodies in other studies, including those of eplontersen.

In Study 1, with duration of treatment up to 85 weeks (mean treatment duration of 445 days (63.2 weeks), range: 57 to 582 days), 53 out of 144 (37%) patients developed treatment-emergent ADAs during treatment with WAINUA. The presence of ADAs did not affect eplontersen plasma C_max or AUC, but increased C_trough. Although anti-drug antibody development was not found to affect the pharmacokinetics, pharmacodynamics, safety, or efficacy of WAINUA in these patients, the available data are too limited to make definitive conclusions.

Carcinogenesis

Carcinogenicity studies have not been conducted with eplontersen.

Mutagenesis

Eplontersen was negative for genotoxicity in in vitro (bacterial reverse mutation, chromosomal aberration in Chinese hamster lung cells) and in vivo (mouse bone marrow micronucleus) assays.

Impairment Of Fertility

Subcutaneous administration of eplontersen (0, 5, 25, or 75 mg/kg) or a mouse-specific surrogate (25 mg/kg) to male and female mice weekly prior to and during mating and continuing in females throughout the period of organogenesis resulted in no adverse effects on fertility.

14 Clinical Studies

The efficacy of WAINUA was demonstrated in a randomized, open-label, multicenter clinical trial in adult patients with polyneuropathy caused by hATTR amyloidosis (Study 1; NCT04136184). Patients were randomized in a 6:1 ratio to receive either 45 mg of WAINUA once every 4 weeks (N=144), or 284 mg of inotersen once per week (N=24), respectively, as subcutaneous injections. Ninety-seven percent of WAINUA-treated patients and 83% of inotersen-treated patients completed at least 35 weeks of the assigned treatment.

Efficacy assessments were based on a comparison of the WAINUA arm of Study 1 with an external placebo group (N=60) in another study (NCT01737398) composed of a comparable population of adult patients with polyneuropathy caused by hATTR amyloidosis.

The efficacy endpoints were the change from baseline to Week 35 in the modified Neuropathy Impairment Scale+7 (mNIS+7) composite score and the change from baseline to Week 35 in the Norfolk Quality of Life-Diabetic Neuropathy (QoL-DN) total score.

The mNIS+7 is an objective assessment of neuropathy and comprises the neuropathy impairment score (NIS) and Modified +7 composite scores. In the version of the mNIS+7 used in the trial, the NIS objectively measures deficits in cranial nerve function, muscle strength, reflexes, and sensations, and the Modified +7 assesses heart rate response to deep breathing, quantitative sensory testing (touch-pressure and heat-pain), and peripheral nerve electrophysiology. The validated version of the mNIS+7 score used in the trial has a range of -22.3 to 346.3 points, with higher scores representing a greater severity of disease.

The clinical meaningfulness of effects on the mNIS+7 was assessed by the change from baseline to Week 35 in Norfolk Quality of Life-Diabetic Neuropathy (QoL-DN) total score. The Norfolk QoL-DN scale is a patient-reported assessment that evaluates the subjective experience of neuropathy in the following domains: physical functioning/large fiber neuropathy, activities of daily living, symptoms, small fiber neuropathy, and autonomic neuropathy. The version of the Norfolk QoL-DN that was used in the trial has a range from -4 to 136 points, with higher scores representing greater impairment.

Treatment with WAINUA resulted in statistically significant improvements in the mNIS+7 and the Norfolk QoL-DN total scores, compared to the external placebo control (p<0.001) at Week 35 (Table 2, Figures 1 and 3). The distributions of changes in mNIS+7 and Norfolk QoL-DN scores from baseline to Week 35 by percent of patients in each category are shown in Figure 2 and Figure 4, respectively.

Figure 1: Change from Baseline in mNIS+7 at Week 35 (Comparison of WAINUA Treatment in Study 1 to an External Placebo Control*)

Figure_1 - figure 1

* External placebo group from another randomized controlled trial (NCT01737398).
Based on an analysis of covariance (ANCOVA) model. Patients with a missing mNIS+7 at Week 35 had values multiply imputed using an imputation model.

Figure 2: Histogram of mNIS+7 Change from Baseline at Week 35 (Comparison of WAINUA Treatment in Study 1 to an External Placebo Control*)

* External placebo group from another randomized controlled trial (NCT01737398).
Categories are mutually exclusive; patients who died before Week 35 are summarized in the Death category only; missing mNIS+7 values not imputed; patients with missing values at Week 35 presented in the Missing category.

Figure 3: Change from Baseline in Norfolk QoL-DN Total Score at Week 35 (Comparison of WAINUA Treatment in Study 1 to an External Placebo Control*)

* External placebo group from another randomized controlled trial (NCT01737398).
Based on an analysis of covariance (ANCOVA) model. Patients with a missing Norfolk QoL-DN at Week 35 had values multiply imputed using an imputation model.

Figure 4: Histogram of Norfolk QoL-DN Total Score Change from Baseline at Week 35 (Comparison of WAINUA Treatment in Study 1 to an External Placebo Control*)

* External placebo group from another randomized controlled trial (NCT01737398).
Categories are mutually exclusive; patients who died before Week 35 are summarized in the Death category only; missing Norfolk QoL-DN values not imputed; patients with missing values at Week 35 presented in the Missing category.

Patients receiving WAINUA experienced similar improvements relative to those in the external placebo in mNIS+7, and Norfolk QoL-DN score across subgroups including age, sex, race, region, Val30Met variant status, and disease stage.

16.1 How Supplied

WAINUA injection is a sterile, preservative-free, clear, colorless to yellow solution supplied in a single-dose autoinjector. Each autoinjector of WAINUA is filled to deliver 0.8 mL of solution containing 45 mg of eplontersen.

WAINUA is available in cartons containing one 45 mg single-dose autoinjector each.

The NDC is: 0310-9400-01.

16.2 Storage And Handling

Store refrigerated at 2°C to 8°C (36°F to 46°F) in the original carton protected from light.

If needed, WAINUA can be kept at room temperature (up to 30°C [86°F]) in the original carton for up to 6 weeks. If not used within the 6 weeks stored at room temperature, discard WAINUA.

Do not freeze. Do not expose to heat.

17 Patient Counseling Information

Advise the patient to read the FDA-approved patient labeling (Patient Information and Instructions for Use).

Recommended Vitamin A Supplementation

Inform patients that WAINUA treatment leads to a decrease in vitamin A levels measured in the serum. Instruct patients to take the recommended daily allowance of vitamin A. Advise patients to contact their healthcare provider if they experience ocular symptoms suggestive of vitamin A deficiency (e.g., night blindness, dry eyes) and refer them to an ophthalmologist if they develop these symptoms [see Warnings and Precautions (5.1)].

Pregnancy

Instruct patients that if they are pregnant or plan to become pregnant while taking WAINUA they should inform their healthcare provider. Advise patients of the potential risk to the fetus, including that WAINUA treatment leads to a decrease in serum vitamin A levels [see Use in Special Populations (8.1)].

Distributed by: AstraZeneca Pharmaceuticals LP, Wilmington, DE 19850

©AstraZeneca 2023

Other

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Especially tell your healthcare provider if you take:

Ask your healthcare provider or pharmacist if you are not sure if you take any of these medicines. Know the medicines you take. Keep a list of them to show your healthcare provider or pharmacist when you get a new medicine.

The most common side effects of WAINUA include decreased vitamin A and vomiting.

These are not all of the possible side effects of WAINUA. For more information, ask your healthcare provider or pharmacist.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1‑800-FDA-1088.

Keep WAINUA and all medicines out of the reach of children.

This Patient Information has been approved by the U.S. Food and Drug Administration.              Approved: 12/2023

Package/Label Principal Display Panel

NDC 0310-9400-01                                                        Rx only

WAINUA™                                                                    45 mg/0.8 mL

(eplontersen) injection

for subcutaneous use

Each WAINUA autoinjector contains 45 mg eplontersen

(equivalent to 47 mg eplontersen sodium) in 0.8 mL of solution, for single-dose only.

Store refrigerated at 2°C to 8°C (36°F to 46°F) in the original carton protected from light.

Do not freeze. Do not expose to heat.

1 single-dose autoinjector

                                                                                  IONIS™   AstraZeneca

Carton_Label_45mg_per_0.8mL - Carton Label 45mg per 0.8mL