Sodium Iodide I 131 Diagnostic

1 INDICATIONS AND USAGE Sodium Iodide I 131 Capsules Diagnostic is indicated for use in adults for: Assessment of thyroid function using radioactive iodine (RAI) uptake test Imaging the thyroid (scintigraphy) Sodium Iodide I 131 Capsules Diagnostic is a radioactive diagnostic agent indicated for the assessment of thyroid function and for thyroid imaging.

2 DOSAGE AND ADMINISTRATION Use careful handling with appropriate safety measures to minimize radiation exposure to patients and healthcare workers. ( 2.1 , 5.2 ) Follow suitable radioactivity calibration prior to administration. ( 2.1 ) In an adult patient, recommended doses are ( 2.2 ): Thyroid Function: 0.185 to 1.1 megabecquerels (MBq) [5 to 30 microcuries (microCi)] Thyroid Imaging: 1.85 to 3.70 MBq (50 to 100 microCi) 2.1 Radiation Safety Sodium Iodide I 131 Capsules Diagnostic is a radioactive drug and should be handled with appropriate safety measures to minimize radiation exposure to the patient and healthcare worker [see Warnings and Precautions ( 5.2 ) ]. Use waterproof gloves during the entire handling and administration procedure. Maintain adequate shielding during the life of the product. Open the capsule-containing vial in a well ventilated hood to avoid exposure to trace levels of volatile I-131 which may be present. Measure patient dose by a suitable radioactivity calibration system immediately prior to administration. 2.2 Recommended Dosage and Administration Instructions Administer Sodium Iodide I 131 Capsules Diagnostic orally prior to scanning. The recommended dose of Sodium Iodide I 131 Capsules Diagnostic for an adult patient is the following: Thyroid Function: 0.185 to 1.1 megabecquerels (MBq) [5 to 30 microcuries (microCi)]. Administer 24 hours before uptake measurement. Thyroid Imaging (Scintigraphy): 1.85 to 3.70 MBq (50 to 100 microCi). Administer 16 -24 hours before imaging. Consult the color-coded decay calendar that is updated in January of every year to determine which colored capsule(s) correspond to the prescribed dose: https://www.draximage.com/products/us/draximage-i-131-diagnostic-capsules/ or calculate the correct dose from the date and time of calibration provided on the container label. Prior to Sodium Iodide I 131 Capsules Diagnostic Administration Obtain a pregnacy test in females of reproductive potential prior to administration to verify the absence of pregnancy [see Contraindications ( 4 ) and Use in Specific Populations ( 8.1, 8.3 ) ]. Advise patients to maintain a low-iodine diet two weeks prior to radioiodine administration and continue for several days during the uptake or imaging process [see Drug Interactions ( 7 ) ]. Advise patients to fast at least 2 hours before and 2 hours after administration to ensure absorption. Advise patients to hydrate before and after administration of radioiodine and void frequently to ensure rapid excretion. 2.3 Radiation Dosimetry The biokinetic and radiation dose distributions associated with thyroid uptake of iodide I 131 depend on dietary intake of stable iodine. A range of uptake percentages in an average adult (73.7 kg) are shown in Table 1. For a thyroid blocked from iodide uptake in the production of hormones, the effective half-life of iodide I 131 is approximately 1.4 hours; for "low" to "high" uptake, the effective half-life of I 131 ranges from approximately 80 to 90 hours. Table 1 Absorbed dose per unit activity sodium iodide I 131 administered orally (mGy/MBq) in adult (73.7-kg reference model) Organ Thyroid uptake of I 131 (% administered activity A 0 ) 24 h after oral administration Blocked thyroid (0% A 0 ) Low uptake (16% A 0 ) Medium uptake (26% A 0 ) High uptake (36% A 0 ) Adrenals 0.044 0.051 0.055 0.059 Bone surfaces 0.030 0.089 0.12 0.16 Brain 0.021 0.093 0.13 0.17 Breast 0.020 0.038 0.048 0.058 Gallbladder wall 0.037 0.043 0.046 0.049 Gastrointestinal tract Stomach wall 0.87 0.77 0.71 0.66 Small intestine wall 0.035 0.033 0.032 0.032 Colon wall 0.14 0.14 0.14 0.14 (Upper large intestine wall) 0.12 0.12 0.12 0.12 (Lower large intestine wall) 0.17 0.17 0.17 0.16 Heart wall 0.062 0.089 0.10 0.12 Kidneys 0.27 0.27 0.27 0.27 Liver 0.050 0.093 0.12 0.14 Lungs 0.053 0.10 0.13 0.15 Muscles 0.026 0.084 0.12 0.15 Oesophagus 0.024 0.10 0.14 0.19 Ovaries 0.038 0.037 0.036 0.035 Pancreas 0.060 0.064 0.066 0.068 Red marrow 0.031 0.072 0.095 0.12 Salivary glands 0.27 0.22 0.19 0.16 Skin 0.019 0.043 0.057 0.071 Spleen 0.064 0.069 0.072 0.075 Testes 0.025 0.024 0.023 0.22 Thymus 0.024 0.10 0.14 0.19 Thyroid 2.2 280 430 580 Urinary bladder wall 0.54 0.45 0.39 0.34 Uterus 0.045 0.042 0.040 0.038 Remaining organs 0.029 0.84 0.11 0.15 Effective dose per administered activity (mSv/MBq) 0.28 14 22 29

4 CONTRAINDICATIONS Sodium Iodide I 131 Capsules Diagnostic is contraindicated in pregnancy [see Warnings and Precautions ( 5.1 ) , Use in Specific Populations ( 8.1 ) ]. Pregnancy

5 WARNINGS AND PRECAUTIONS Fetal Toxicity – I 131 can cause severe and irreversible hypothyroidism in the neonate. Verify absence of pregnancy before administering the product. ( 4 , 5.1 , 8.1, 8.3 ) Radiation Risk – I 131 contributes to patients’s long-term cumulative radiation exposure, which is associated with an increased risk of cancer. Ensure safe handling to minimize radiation exposure. ( 5.2 ) 5.1 Fetal Toxicity Sodium Iodide I 131 Capsules Diagnostic is contraindicated in pregnancy because sodium iodide I 131 crosses the placenta and can cause severe and irreversible hypothyroidism in the neonate. Multiple reports in the literature describe neonatal hypothryroidism following in utero exposure to sodium iodide I 131. Some of these cases were severe and irreversible. Verify pregnancy status of females of reproductive potential prior to administering Sodium Iodide I 131 Capsules Diagnostic [see Use in Specific Populations ( 8.1, 8.3 ) ]. 5.2 Radiation Exposure Sodium Iodide I 131 Capsules Diagnostic contributes to a patient’s overall long-term cumulative radiation exposure, which is associated with an increased risk of cancer. Follow safe administration instructions to minimize radiation exposure to the patient and healthcare providers [see Dosage and Administration ( 2.1 ) ]. 5.3 Risk of Radioactive Uptake Measurement and Imaging Misinterpretation The recent intake of stable iodine in any form, or the use of thyroid or anti-thyroid drugs will affect the uptake of sodium iodide I 131. Question the patient carefully regarding their exposure to these drugs or procedures involving radiographic contrast media [see Drug Interactions ( 7 ) ]. 5.4 Hypersensitivity Reactions Hypersensitivity reactions including anaphylaxis may occur in patients who receive sodium iodide I 131. Although iodine is not considered an allergen, hypersensitivity reactions may occur in relation with excipients or chemical component of the capsule, such as sodium thiosulfate. Obtain and document an allergy history, particularly a sulfite allergy. Emergency resuscitation equipment and personnel should be immediately available [see Adverse Reactions ( 6 ) ].

7 DRUG INTERACTIONS Certain drugs and iodine-containing foods interfere with the accumulation of radioiodide by the thyroid. Review the patients history, current medications, and recent diagnostic tests prior to the administration of Sodium Iodide I-131 Capsules Diagnostic. Advise patients to maintain a low-iodine diet two weeks prior to radioiodine administration and continue for several days during the uptake or imaging process and to discontinue the following products before they undergo the procedure as shown in Table 3: Table 3 Pharmaceuticals/OTCs/Agents Blocking Radioiodine Uptake ​Products Recommended duration of withdrawal Thionamide medications (e.g., propylthiouracil, methimazole carbimazole) 3 days Multivitamins containing iodide 10 days Natural or synthetic thyroid hormones triiodothyronine thyroxine 2 weeks 4 weeks Iodine containing foods: iodinized salt, dairy products, egg yolks, seafood, turkey, and liver 2 weeks Kelp, agar, carrageenan, Lugol solution 3 weeks Saturated solution of potassium iodide 3 weeks Topical iodine (e.g., surgical skin preparation) 3 weeks Radiographic contrast agents Water soluble Lipophilic 2 months 6 months Amiodarone 6 months The recent intake of iodine in any form or the use of thyroid or anti-thyroid drugs will affect the uptake of sodium iodide I 131. ( 5.3 , 7 )

6 ADVERSE REACTIONS The following adverse reaction has been described elsewhere in the labeling: Hypersensitivity Reactions [see Warnings and Precautions ( 5.4 ) ] The following adverse reactions have been identified during post-approval use from Sodium Iodide I 131 Capsules Diagnostic. Because these reactions are voluntarily reported from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Adverse reactions associated with the administration of Sodium Iodide I 131 Capsules Diagnostic are: Gastrointestinal disorders: vomiting, nausea, and diarrhea General disorders and administration site conditions: local thyroid swelling Immune system disorders: hypersensitivity reactions Skin and subcutaneous tissue disorders: itching, rash, hives, and erythema Common adverse reactions reported with diagnostic doses of sodium iodide I 131 include nausea, vomiting, itching, rash and hives. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Jubilant DraxImage Inc. at 1-888-633-5343 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

8.1 Pregnancy Risk Summary Sodium Iodide I 131 Capsules Diagnostic is contraindicated in pregnancy because fetal exposure can lead to neonatal hypothyroidism, which in some cases is severe and irreversible. Data from the published literature describe reports of neonatal thyroid abnormalities after fetal exposure, including agenesis of the thyroid and hypothyroidism (see Clinical Considerations, Data ). No animal reproductive studies have been conducted. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies are 2-4% and 15-20%, respectively. Clinical Considerations Fetal/Neonatal Adverse Reactions A fetus exposed to sodium iodide I 131 can develop neonatal hypothyroidism. Delay in diagnosis of neonatal hypothyroidism after exposure to sodium iodide I 131 in utero can result in severe sequelae such as decreased mental capacity and delayed skeletal maturation. Monitor thyroid function in any infant born after in utero exposure to sodium iodide I 131. Data Human Data Literature reports of maternal exposures to sodium iodide I 131 at doses of 330-8300 MBq during 4-26 weeks estimated gestational age. There were various adverse pregnancy outcomes; the most common was hypothyroidism in infants and children.