Koselugo

Selumetinib · Capsule · Oral

Uses

1 INDICATIONS AND USAGE KOSELUGO is indicated for the treatment of adult and pediatric patients 1 year of age and older with neurofibromatosis type 1 (NF1) who have symptomatic, inoperable plexiform neurofibromas (PN) [see Dosage and Administration (2) ]. KOSELUGO is a kinase inhibitor indicated for the treatment of adult and pediatric patients 1 year of age and older with neurofibromatosis type 1 (NF1) who have symptomatic, inoperable plexiform neurofibromas (PN). ( 1 )

Dosage and administration

• KOSELUGO capsules: The recommended dosage is 25 mg/m 2 , swallowed whole, taken orally twice daily with or without food (see Table 1) . (2.1 , 2.2 )
• KOSELUGO oral granules: The recommended dosage is equivalent to 25 mg/m 2 , sprinkled onto or mixed with soft food and taken orally twice daily (see Table 2). ( 2.1 , 2.2 )
• Moderate hepatic impairment (Child-Pugh B): The recommended dosage is 20 mg/m 2 orally twice daily (see Tables 6 and 7) . ( 2.2 , 2.4 )
• Severe hepatic impairment (Child-Pugh C): The recommended dosage has not been established. ( 2.4 , 8.6 )
• Strong or Moderate CYP3A4 Inhibitors or Fluconazole: If coadministration with strong or moderate CYP3A4 inhibitors or fluconazole cannot be avoided, reduce the dose of KOSELUGO (see Tables 8 and 9) . ( 2.5 ) 2.1 Recommended Dosage The recommended dosage of KOSELUGO capsules ( see Table 1 ) and KOSELUGO oral granules ( see Table 2 ) for adult and pediatric patients 1 year of age and older, based on body surface area, is 25 mg/m 2 orally twice daily, until disease progression or unacceptable toxicity [see Dosage and Administration (2.2)]. Table 1 Recommended Dosage: KOSELUGO Capsules Body Surface Area The recommended dosage of KOSELUGO capsules for patients with a BSA less than 0.55 m 2 has not been established. KOSELUGO Capsules 0.55 – 0.69 m 2 20 mg in the morning and 10 mg in the evening 0.70 – 0.89 m 2 20 mg twice daily 0.90 – 1.09 m 2 25 mg twice daily 1.10 – 1.29 m 2 30 mg twice daily 1.30 – 1.49 m 2 35 mg twice daily 1.50 – 1.69 m 2 40 mg twice daily 1.70 – 1.89 m 2 45 mg twice daily ≥ 1.90 m 2 50 mg twice daily Table 2 Recommended Dosage: KOSELUGO Oral Granules Body Surface Area The recommended dosage of KOSELUGO oral granules for patients with a BSA less than 0.40 m 2 has not been established. KOSELUGO Oral Granules 0.40 – 0.59 m 2 12.5 mg twice daily 0.60 – 0.69 m 2 15 mg twice daily 0.70 – 0.89 m 2 20 mg twice daily 0.90 – 1.09 m 2 25 mg twice daily 1.10 – 1.29 m 2 30 mg twice daily 1.30 – 1.49 m 2 35 mg twice daily 1.50 – 1.69 m 2 40 mg twice daily 1.70 – 1.89 m 2 45 mg twice daily ≥ 1.90 m 2 50 mg twice daily 2.2 Administration KOSELUGO is available in two dosage forms: KOSELUGO capsules and KOSELUGO oral granules. Prescribe KOSELUGO oral granules for patients who have difficulty swallowing whole capsules. KOSELUGO Capsules
• Administer KOSELUGO capsules to patients who can swallow a whole capsule.
• Swallow KOSELUGO capsules whole. Do not open, chew or crush KOSELUGO capsules.
• KOSELUGO capsules may be administered with or without food. KOSELUGO Oral Granules Administer KOSELUGO oral granules to patients who have difficulty swallowing a whole capsule. Sprinkle KOSELUGO oral granules on or mix with a small amount (about 1 to 3 teaspoons) of smooth yogurt, or fruit puree containing the following fruits: apple, banana, pear, or strawberry and consume within 30 minutes of preparation. If not consumed within 30 minutes of preparation, discard and prepare a new dose. If a dose has been partially consumed within 30 minutes of preparation, discard the remainder of the dose and do not prepare a new dose, aim to complete dosing within 30 minutes next time. The KOSELUGO oral granules should be free-flowing. Do NOT use if the oral granules are clumped or stuck inside the capsule shell. Instruct the patient or caregiver to contact their pharmacy if this happens. Discard the empty capsule shells after use. Do NOT swallow, chew, or dissolve the capsule shells of KOSELUGO oral granules. Do NOT chew or crush the KOSELUGO oral granules. Do NOT add oral granules to liquids. Do NOT mix KOSELUGO oral granules in grapefruit or any juice, fruit puree or jam containing Seville orange. Missed Dose If a dose of KOSELUGO capsules or KOSELUGO oral granules is missed, make up that dose unless the next dose is due within 6 hours. Vomiting If vomiting occurs after taking a dose of KOSELUGO capsules or KOSELUGO oral granules, do not take an additional dose. Take the next dose at the regular scheduled time. 2.3 Dosage Modifications for Adverse Reactions The recommended dose reductions for adverse reactions for KOSELUGO capsules and KOSELUGO oral granules are provided in Tables 3 and 4, respectively. Table 3 Recommended Dose Reductions for KOSELUGO Capsules for Adverse Reactions Body Surface Area First Dose Reduction (mg/dose) Second Dose Reduction (mg/dose) Morning Evening Morning Evening 0.55 – 0.69 m 2 10 10 10 mg once daily 0.70 – 0.89 m 2 20 10 10 10 0.90 – 1.09 m 2 25 10 10 10 1.10 – 1.29 m 2 25 20 20 10 1.30 – 1.49 m 2 25 25 25 10 1.50 – 1.69 m 2 30 30 25 20 1.70 – 1.89 m 2 35 30 25 20 ≥ 1.90 m 2 35 35 25 25 Permanently discontinue KOSELUGO capsules in patients unable to tolerate two dose reductions. Table 4 Recommended Dose Reductions for KOSELUGO Oral Granules for Adverse Reactions Body Surface Area First Dose Reduction (mg/dose) Second Dose Reduction (mg/dose) Morning Evening Morning Evening 0.40 – 0.59 m 2 10 10 7.5 7.5 0.60 – 0.69 m 2 12.5 12.5 10 10 0.70 – 0.89 m 2 15 15 12.5 12.5 0.90 – 1.09 m 2 20 20 15 15 1.10 – 1.29 m 2 22.5 22.5 15 15 1.30 – 1.49 m 2 25 25 25 10 1.50 – 1.69 m 2 30 30 25 20 1.70 – 1.89 m 2 35 30 25 20 ≥ 1.90 m 2 35 35 25 25 Permanently discontinue KOSELUGO oral granules in patients unable to tolerate two dose reductions. The recommended dosage modifications of KOSELUGO capsules and KOSELUGO oral granules for adverse reactions are provided in Table 5. Table 5 Recommended Dosage Modifications for Adverse Reactions Severity of Adverse Reaction Recommended Dosage Modifications for KOSELUGO capsules and KOSELUGO oral granules Left Ventricular Dysfunction [see Warnings and Precautions (5.1) ]
• Asymptomatic decrease in left ventricular ejection fraction (LVEF) of 10% or greater from baseline and less than lower level of normal Withhold until resolution. Resume at reduced dose.
• Symptomatic decreased LVEF
• Grade 3 or 4 decreased LVEF Permanently discontinue.

Dosage forms and strengths

Capsules:
• 10 mg selumetinib: white to off-white, opaque, hard capsule sealed with a clear band and marked with “SEL 10” in black ink.
• 25 mg selumetinib: blue, opaque, hard capsule sealed with a clear band and marked with “SEL 25” in black ink. Oral Granules:
• 5 mg selumetinib: off-white to light-yellow free-flowing oral granules contained within capsules. The capsules have a yellow cap and white body. The cap is printed with “sel 5” in black ink, and body is printed with a sprinkle capsule image indicating opening.
• 7.5 mg selumetinib: off-white to light-yellow free-flowing oral granules contained within capsules. The capsules have a pink cap and white body. The cap is printed with “sel 7.5” in black ink, and body is printed with a sprinkle capsule image indicating opening.
• Capsules: 10 mg and 25 mg of selumetinib. ( 3 )
• Oral Granules: 5 mg and 7.5 mg of selumetinib. ( 3 )

Contraindications

None. None. ( 4 )

Warnings and precautions

• Left Ventricular Dysfunction : Assess ejection fraction prior to initiating treatment, every 3 months during the first year, then every 6 months thereafter and as clinically indicated. Withhold, reduce the dose, or permanently discontinue KOSELUGO based on severity of adverse reaction. ( 2.3 , 5.1 )
• Ocular Toxicity : Conduct ophthalmic assessments prior to initiating KOSELUGO, at regular intervals during treatment and for new or worsening visual changes. Permanently discontinue KOSELUGO for retinal vein occlusion (RVO). Withhold KOSELUGO for retinal pigment epithelial detachment (RPED), monitor with optical coherence tomography assessments until resolution, and resume at reduced dose. ( 2.3 , 5.2 )
• Gastrointestinal Toxicity : Advise patients to start an anti-diarrheal agent immediately after the first episode of loose stool and to increase fluid intake. Withhold, reduce the dose, or permanently discontinue KOSELUGO based on severity of adverse reaction. ( 2.3 , 5.3 )
• Skin Toxicity : Monitor for severe skin rashes. Withhold, reduce the dose, or permanently discontinue KOSELUGO based on severity of adverse reaction. ( 2.3 , 5.4 )
• Increased Creatine Phosphokinase (CPK) : Increased CPK and rhabdomyolysis can occur. Obtain serum CPK prior to initiating KOSELUGO, periodically during treatment, and as clinically indicated. If increased CPK occurs, evaluate for rhabdomyolysis or other causes. Withhold, reduce the dose, or permanently discontinue KOSELUGO based on severity of adverse reaction. ( 2.3 , 5.5 )
• Increased Vitamin E Levels and Increased Risk of Bleeding (KOSELUGO Capsules) : KOSELUGO capsules contain vitamin E and daily intake of vitamin E that exceeds the recommended or safe limits may increase the risk of bleeding. An increased risk of bleeding may occur in patients co-administered vitamin-K antagonists or anti-platelet agents. KOSELUGO oral granules do not contain vitamin E. ( 5.6 )
• Embryo-Fetal Toxicity: Can cause fetal harm. Advise patients of reproductive potential of the potential risk to a fetus and to use effective contraception ( 5.7 , 8.1 , 8.3 ). 5.1 Left Ventricular Dysfunction KOSELUGO can cause cardiomyopathy, defined as a decrease in left ventricular ejection fraction (LVEF) ≥ 10% below baseline. KOSELUGO has not been studied in patients with a history of clinically significant cardiac disease or LVEF less than 55% prior to treatment. Pediatric Patients In the NF1 PN pediatric safety pool (N = 134) [see Adverse Reactions (6.1) ], Grade 2 LVEF decrease [Grade 2 LVEF decrease (40% to 50%; 10 to 19% drop from baseline)], based on reported adverse reactions, occurred in 17% of evaluable patients. Decreased LVEF of ≥ 20% occurred in 0.7% of patients and resulted in dose interruption and dose reduction. Decreased LVEF resolved in 75% of these patients. The median time to first onset of maximum CTCAE grade LVEF decrease was approximately 12 months (median duration approximately 3 months). Adult Patients In the KOMET adult NF1 PN study (N = 71) [see Adverse Reactions (6.1) ], Grade 2 LVEF decrease [Grade 2 LVEF decrease (40% to 50%; 10 to 19% drop from baseline)], based on echocardiogram results, occurred in 14% of evaluable patients. Decreased LVEF resulted in dose interruption in 1.4% of patients. The median time to first onset of maximum CTCAE grade LVEF decrease was approximately 4 months (median duration approximately 4 months). Assess ejection fraction by echocardiogram prior to initiating treatment, every 3 months during the first year of treatment, every 6 months thereafter, and as clinically indicated. Withhold, reduce dose, or permanently discontinue KOSELUGO based on severity of adverse reaction [see Dosage and Administration (2.3)]. In patients who interrupt KOSELUGO for decreased LVEF, obtain an echocardiogram or a cardiac MRI every 3 to 6 weeks until resolution. Upon resolution of decreased LVEF to greater than or equal to the institutional LLN, obtain an echocardiogram or a cardiac MRI every 2 to 3 months or as directed by the cardiologist. 5.2 Ocular Toxicity KOSELUGOcan cause ocular toxicity, including retinal vein occlusion (RVO), retinal pigment epithelial detachment (RPED), central serous retinopathy (CSR), and blurred vision. Pediatric Patients In the NF1 PN pediatric safety pool (N = 134) [see Adverse Reactions (6.1)], blurred vision, photophobia, cataracts, ocular hypertension, and retinal tear occurred in 13% of pediatric patients receiving KOSELUGO. Blurred vision resulted in dose interruption in 1.5% of patients. Ocular toxicity resolved in 72% of these patients. Grade 1 asymptomatic transient subretinal fluid was observed in 6% of patients, none required dose modification and of these 88% resolved. Grade 1 retinopathy occurred in 0.7% of patients, and all events resolved without dose modification. RPED occurred in the pediatric population during treatment with single agent KOSELUGO and resulted in permanent discontinuation. Adult Patients In the KOMET adult NF1 PN study (N = 71) [see Adverse Reactions (6.1)], blurred vision and vitreous floaters occurred in 6% of patients receiving KOSELUGO. Serious ocular toxicities including RVO and RPED, occurred in an unapproved population of adult patients with multiple tumor types who received KOSELUGO as a single agent or in combination with other anti cancer agents. Postmarketing Experience In postmarketing experience [see Adverse Reactions (6.2)], cases of RPED/CSR occurred. Conduct comprehensive ophthalmic assessments prior to initiating KOSELUGO, at regular intervals during treatment, and for new or worsening visual changes. Permanently discontinue KOSELUGO in patients with RVO. Withhold KOSELUGO in patients with RPED, follow up with optical coherence tomography assessments every 3 weeks until resolution, and resume KOSELUGO at a reduced dose.

Side effects

The following clinically significant adverse reactions are described elsewhere in the labeling:
• Left Ventricular Dysfunction [see Warnings and Precautions (5.1) ]
• Ocular Toxicity [see Warnings and Precautions (5.2) ]
• Gastrointestinal Toxicity [see Warnings and Precautions (5.3) ]
• Skin Toxicity [see Warnings and Precautions (5.4) ]
• Increased Creatine Phosphokinase [see Warnings and Precautions (5.5) ] Most common adverse reactions in pediatric patients (≥ 40%) are: vomiting, diarrhea, increased creatine phosphokinase, dry skin, paronychia, nausea, dermatitis acneiform, and pyrexia. ( 6.1 ) Most common adverse reactions in adult patients (≥ 40%) are rash (all), dermatitis acneiform, and diarrhea. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact AstraZeneca 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 a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The NF1 PN pediatric safety pool described in the WARNINGS AND PRECAUTIONS reflects exposure to KOSELUGO at the recommended dosage in 134 pediatric patients in SPRINKLE (N = 36) (NCT05309668), SPRINT Phase I (N = 24) (NCT01362803), SPRINT Phase II Stratum 1 (N = 50) [see Clinical Studies (14.1) ] , and Phase I Food Effect Study (N = 24) (NCT05101148). Among pediatric patients, the duration of KOSELUGO exposure was 12 months or longer (80%), more than 2 years (44%), or more than 3 years (37%). The most common adverse reactions in pediatric patients (≥ 40%) are vomiting, diarrhea, increased creatine phosphokinase, dry skin, paronychia, nausea, dermatitis acneiform, and pyrexia. In the KOMET adult NF1 PN study, 71 adult patients received KOSELUGO at the recommended dosage [see Clinical Studies (14.1) ] . Among adult patients, the duration of KOSELUGO exposure in the randomized period was 6 months or longer (92%), and 11 months or longer (66%). The most common adverse reactions in adult patients (≥ 40%) are rash (all), dermatitis acneiform, and diarrhea. Neurofibromatosis Type 1 (NF1) with Inoperable Plexiform Neurofibromas (PN) Pediatrics 2-18 years of Age (SPRINT Phase II Stratum 1) The safety of KOSELUGO was evaluated in SPRINT Phase II Stratum 1 [see Clinical Studies (14.1) ] . Eligible patients were 2-18 years of age with neurofibromatosis type 1 (NF1) who had inoperable plexiform neurofibromas (PN) that was causing significant morbidity. Patients were excluded for abnormal LVEF, uncontrolled hypertension (blood pressure ≥ the 95th percentile for age, height, and sex), any current or past history of RVO or RPED, intraocular pressure > 21 mmHg (or upper limit of normal adjusted by age), uncontrolled glaucoma, and inability to swallow whole capsules. Patients received KOSELUGO 25 mg/m 2 orally twice daily (N = 50). Among these patients, 88% were exposed for 12 months or longer and 66% were exposed for greater than 2 years. Serious adverse reactions occurred in 24% of patients who received KOSELUGO. Serious adverse reactions that occurred in 2 or more patients were anemia, hypoxia and diarrhea. Permanent discontinuation due to an adverse reaction occurred in 12% of patients who received KOSELUGO. Adverse reactions resulting in permanent discontinuation of KOSELUGO included increased blood creatinine, increased weight, diarrhea, paronychia, malignant peripheral nerve sheath tumor, acute kidney injury, and skin ulcer. Dosage interruptions and dose reductions due to adverse reactions occurred in 80% and 24% of patients who received KOSELUGO, respectively. Adverse reactions requiring a dosage interruption or reduction in ≥ 5% of patients were vomiting, paronychia, diarrhea, nausea, abdominal pain, rash, skin infection, influenza-like illness, pyrexia and weight gain. The most common adverse reactions (≥ 40%) were vomiting, rash (all), abdominal pain, diarrhea, nausea, dry skin, fatigue, musculoskeletal pain, pyrexia, acneiform rash, stomatitis, headache, paronychia, and pruritus. Table 10 presents the adverse reactions in SPRINT Phase II Stratum 1. Table 10 Adverse Reactions (≥ 20%) in Patients Who Received KOSELUGO in SPRINT Phase II Stratum 1 Adverse Reaction KOSELUGO (N = 50) All Grades (%) Grade ≥ 3 (%) * Gastrointestinal Vomiting 82 6 Abdominal pain Abdominal pain includes abdominal pain; abdominal pain upper 76 0 Diarrhea 70 16 Nausea 66 2 Stomatitis Stomatitis includes stomatitis; mouth ulceration 50 0 Constipation 34 0 Skin and Subcutaneous Tissue Rash (all) Rash (all) includes dermatitis acneiform; rash maculo-papular; erythema; rash pustular; rash; urticaria; exfoliative rash; rash pruritic; rash erythematous 80 6 Dry skin 60 0 Rash acneiform Rash (acneiform) includes dermatitis acneiform 50 4 Paronychia Paronychia includes paronychia; nail infection 48 6 Pruritus 46 0 Dermatitis Dermatitis includes dermatitis; dermatitis atopic; dermatitis diaper; eczema; seborrheic dermatitis; skin irritation 36 4 Hair changes Hair changes include alopecia; hair color change 32 0 Musculoskeletal and Connective Tissue Musculoskeletal pain Musculoskeletal pain includes pain in extremity; back pain; neck pain; musculoskeletal pain 58 0 General Fatigue Fatigue includes fatigue; malaise 56 0 Pyrexia 56 8 Edema Edema includes peripheral swelling; edema; localized edema 20 0 Nervous System Headache 48 2 Respiratory, Thoracic and Mediastinal Epistaxis 28 0 Renal and Urinary System Hematuria 22 2 Proteinuria 22 0 Metabolism and Nutrition Decreased appetite 22 0 Cardiac System Decreased ejection fraction 22 0 Sinus tachycardia 20 0 Infections Skin infection Skin infection includes skin infection; abscess; cellulitis; impetigo; staphylococcal skin infection 20 2 * All events were Grade 3.

Drug interactions

• Strong or Moderate CYP3A4 Inhibitors or Fluconazole : Avoid coadministration of strong or moderate CYP3A4 inhibitors or fluconazole with KOSELUGO. If coadministration cannot be avoided, reduce the dose of KOSELUGO. ( 2.5 , 7.1 )
• Strong or Moderate CYP3A4 Inducers : Avoid concomitant use of strong and moderate CYP3A4 inducers. ( 7.1 ) 7.1 Effect of Other Drugs on KOSELUGO Strong or Moderate CYP3A4 Inhibitors or Fluconazole Management
• Avoid concomitant use of strong or moderate CYP3A4 inhibitors or fluconazole with KOSELUGO. If coadministration with strong or moderate CYP3A4 inhibitors or fluconazole cannot be avoided, reduce KOSELUGO dosage [see Dosage Modifications for Drug Interactions (2.5) ]. Clinical Impact
• Concomitant use of KOSELUGO with a strong or moderate CYP3A4 inhibitor or fluconazole increased selumetinib plasma concentrations [see Clinical Pharmacology (12.3) ] , which may increase the risk of adverse reactions. Strong or Moderate CYP3A4 Inducers Management
• Avoid concomitant use of strong or moderate CYP3A4 inducers with KOSELUGO. Clinical Impact
• Concomitant use of KOSELUGO with a strong or moderate CYP3A4 inducer decreased selumetinib plasma concentrations [see Clinical Pharmacology (12.3) ] , which may reduce KOSELUGO efficacy. Vitamin E Management
• Supplemental vitamin E is not recommended if daily vitamin E intake (including the amount of vitamin E in KOSELUGO capsules and supplement) will exceed the recommended or safe limits.
• Monitor for bleeding in patients administered a vitamin‑K antagonist or an anti‑platelet agent with KOSELUGO capsules. Increase INR monitoring, as appropriate, in patients taking a vitamin‑K antagonist [see Warnings and Precautions (5.3) ] . Clinical Impact
• KOSELUGO capsules contain vitamin E and daily vitamin E intake that exceeds the recommended or safe limits may increase the risk of bleeding. An increased risk of bleeding may occur in patients taking a vitamin‑K antagonist or an anti‑platelet agent with KOSELUGO capsules.

Use in specific populations

• Lactation: Advise not to breastfeed. (8.2) 8.1 Pregnancy Risk Summary Based on findings from animal studies and its mechanism of action [see Clinical Pharmacology (12.1) ] , KOSELUGO can cause fetal harm when administered to a pregnant woman. There are no available data on the use of KOSELUGO in pregnant women to evaluate drug-associated risk. In animal reproduction studies, administration of selumetinib to mice during organogenesis caused reduced fetal weight, adverse structural defects, and effects on embryofetal survival at exposures approximately > 5 times the human exposure at the clinical dose of 25 mg/m 2 twice daily ( see Data ). Advise pregnant women of the potential risk to the fetus. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Human Data In KOMET, a first trimester spontaneous abortion was reported in a patient receiving KOSELUGO. Animal Data In embryo-fetal development studies in mice at doses > 2.5 mg/kg twice daily (~5-times the human exposure based on area under the curve [AUC] at the clinical dose of 25 mg/m 2 twice daily), selumetinib caused increases in post-implantation loss, a reduction in mean fetal and litter weights, and an increased occurrence of open eye and cleft palate, but did not induce significant maternal toxicity. Administration of selumetinib to pregnant mice from gestation Day 6 through lactation Day 20 resulted in reduced pup body weights and fewer pups met the pupil constriction criterion on day 21 post-partum. The incidence of malformations (e.g., prematurely open eye(s) and cleft palate) was increased even at the lowest dose of 0.5 mg/kg twice daily (maternal maximal concentration [C max ] of ~0.6 times the human C max at the clinical dose of 25 mg/m 2 twice daily). 8.2 Lactation Risk Summary There are no data on the presence of selumetinib or its active metabolite in human milk or their effects on the breastfed child or milk production. Selumetinib and its active metabolite were present in the milk of lactating mice ( see Data ). Due to the potential for adverse reactions in a breastfed child, advise women not to breastfeed during treatment with KOSELUGO and for 1 week after the last dose. Data Animal Data Selumetinib and its active metabolite were present in milk from mice dosed with selumetinib throughout gestation and lactation, with a mean plasma/milk ratio of 1.5 in lactating dams dosed at 5 mg/kg twice daily. Administration of selumetinib to dams during gestation and early lactation was associated with adverse events in pups, including reduced growth rates and incidence of malformations [see Use in Specific Populations (8.1) ]. 8.3 Females and Males of Reproductive Potential KOSELUGO can cause fetal harm when administered to a pregnant woman [see Use in Specific Populations (8.1) ] . Pregnancy Testing Verify the pregnancy status of females of reproductive potential prior to initiating KOSELUGO [see Use in Specific Populations (8.1) ] . Contraception Females Advise females of reproductive potential to use effective contraception during treatment and for 1 week after the last dose. Males Advise male patients with female partners of reproductive potential to use effective contraception during treatment with KOSELUGO and for 1 week after the last dose. 8.4 Pediatric Use The safety and effectiveness have been established in pediatric patients 1 year of age and older with NF1 who have inoperable PN and the information on this use is discussed throughout the labeling. The safety and effectiveness of KOSELUGO have not been established in pediatric patients younger than 1 year of age. Animal Toxicity Data In 3-month general toxicology studies, male rats receiving selumetinib at doses ≥ 10 mg/kg daily (~60-times the human exposure based on AUC at the clinical dose of 25 mg/m 2 twice daily) showed growth plate dysplasia. 8.5 Geriatric Use Clinical studies of KOSELUGO did not include a sufficient number of patients aged 65 and over to determine whether they respond differently from younger patients. 8.6 Hepatic Impairment Selumetinib exposures increased in patients with moderate or severe hepatic impairment [see Clinical Pharmacology (12.3) ] . Reduce the dose of KOSELUGO for patients with moderate hepatic impairment (Child-Pugh B). A recommended dosage of KOSELUGO for use in patients with severe hepatic impairment (Child-Pugh C) has not been established [see Dosage and Administration (2.4) ].

Pregnancy

8.1 Pregnancy Risk Summary Based on findings from animal studies and its mechanism of action [see Clinical Pharmacology (12.1) ] , KOSELUGO can cause fetal harm when administered to a pregnant woman. There are no available data on the use of KOSELUGO in pregnant women to evaluate drug-associated risk. In animal reproduction studies, administration of selumetinib to mice during organogenesis caused reduced fetal weight, adverse structural defects, and effects on embryofetal survival at exposures approximately > 5 times the human exposure at the clinical dose of 25 mg/m 2 twice daily ( see Data ). Advise pregnant women of the potential risk to the fetus. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Human Data In KOMET, a first trimester spontaneous abortion was reported in a patient receiving KOSELUGO. Animal Data In embryo-fetal development studies in mice at doses > 2.5 mg/kg twice daily (~5-times the human exposure based on area under the curve [AUC] at the clinical dose of 25 mg/m 2 twice daily), selumetinib caused increases in post-implantation loss, a reduction in mean fetal and litter weights, and an increased occurrence of open eye and cleft palate, but did not induce significant maternal toxicity. Administration of selumetinib to pregnant mice from gestation Day 6 through lactation Day 20 resulted in reduced pup body weights and fewer pups met the pupil constriction criterion on day 21 post-partum. The incidence of malformations (e.g., prematurely open eye(s) and cleft palate) was increased even at the lowest dose of 0.5 mg/kg twice daily (maternal maximal concentration [C max ] of ~0.6 times the human C max at the clinical dose of 25 mg/m 2 twice daily).

Pediatric use

8.4 Pediatric Use The safety and effectiveness have been established in pediatric patients 1 year of age and older with NF1 who have inoperable PN and the information on this use is discussed throughout the labeling. The safety and effectiveness of KOSELUGO have not been established in pediatric patients younger than 1 year of age. Animal Toxicity Data In 3-month general toxicology studies, male rats receiving selumetinib at doses ≥ 10 mg/kg daily (~60-times the human exposure based on AUC at the clinical dose of 25 mg/m 2 twice daily) showed growth plate dysplasia.

Geriatric use

8.5 Geriatric Use Clinical studies of KOSELUGO did not include a sufficient number of patients aged 65 and over to determine whether they respond differently from younger patients.

Overdosage

Dialysis is not effective as KOSELUGO is highly protein bound and is extensively metabolized.

Description

11 DESCRIPTION KOSELUGO contains selumetinib sulfate, a kinase inhibitor. The chemical name is 5-[(4-bromo-2-chlorophenyl)amino]-4-fluoro-6-[(2-hydroxyethoxy)carbamoyl]-1-methyl-1 H -benzimidazol-3-ium hydrogen sulfate. The molecular formula for selumetinib sulfate is C 17 H 17 BrClFN 4 O 7 S and the relative molecular mass is 555.76 g/mol. Selumetinib sulfate has the following structural formula: Selumetinib sulfate is a white to yellow monomorphic crystalline powder that exhibits a pH dependent solubility. Selumetinib sulfate is freely soluble at pH < 1.5, sparingly soluble in the pH range at 1.5 to 3 and slightly soluble at pH > 3. Selumetinib sulfate has two ionizable functions with pKa values of 2.8 and 8.4. KOSELUGO (selumetinib) 10 mg capsules for oral use, contain 10 mg selumetinib (equivalent to 12.1 mg selumetinib sulfate) and the excipient, vitamin E polyethylene glycol succinate. The capsule shell contains carnauba wax, carrageenan, hypromellose, potassium chloride, purified water, and titanium dioxide. The capsule is imprinted with black ink that contains ammonium hydroxide, iron oxide black, propylene glycol, and shellac. KOSELUGO (selumetinib) 25 mg capsules for oral use, contain 25 mg selumetinib (equivalent to 30.25 mg selumetinib sulfate) and the excipient, vitamin E polyethylene glycol succinate. The capsule shell contains carnauba wax and/or cornstarch, carrageenan, FD&C blue 2, ferric oxide yellow, hypromellose, potassium chloride, purified water, and titanium dioxide. The capsule is imprinted with black ink that contains carnauba wax, FD&C Blue 2 aluminum lake, ferric oxide red, ferric oxide yellow, glyceryl monooleate, and shellac. KOSELUGO (selumetinib) 5 mg oral granules contain 5 mg selumetinib (equivalent to 6.05 mg selumetinib sulfate). The uncoated cores contain selumetinib sulfate, glyceryl dibehenate, and stearoyl polyoxylglycerides. The granule coating contains acetone, hypromellose acetate succinate, and stearic acid. The capsule shell contains ferric oxide yellow, hypromellose, and titanium dioxide. The capsule shell is imprinted with black ink that contains butyl alcohol, dehydrated alcohol, ferric oxide black, isopropyl alcohol, potassium hydroxide, propylene glycol, purified water, shellac, and strong ammonia solution. KOSELUGO (selumetinib) 7.5 mg oral granules contain 7.5 mg selumetinib (equivalent to 9.08 mg selumetinib sulfate). The uncoated cores contain selumetinib sulfate, glyceryl dibehenate, and stearoyl polyoxylglycerides. The granule coating contains acetone, hypromellose acetate succinate, and stearic acid. The capsule shell contains ferric oxide red, hypromellose, and titanium dioxide. The capsule shell is imprinted with black ink that contains butyl alcohol, dehydrated alcohol, ferric oxide black, isopropyl alcohol, potassium hydroxide, propylene glycol, purified water, shellac, and strong ammonia solution. structure

Mechanism of action

12.1 Mechanism of Action Selumetinib is an inhibitor of mitogen-activated protein kinase kinases 1 and 2 (MEK1/2). MEK1/2 proteins are upstream regulators of the extracellular signal-related kinase (ERK) pathway. Both MEK and ERK are critical components of the RAS-regulated RAF-MEK-ERK pathway, which is often activated in different types of cancers. In genetically modified mouse models of NF1 that generate neurofibromas that recapitulate the genotype and phenotype of human NF1, oral dosing of selumetinib inhibited ERK phosphorylation, and reduced neurofibroma numbers, volume, and proliferation.

How supplied

How Supplied Selumetinib Capsules Strength Description Capsules per Bottle NDC Number 10 mg White to off-white, opaque, hard capsule sealed with a clear band and marked with “SEL 10” in black ink. 60 0310-0610-60 28 0310-0610-28 25 mg Blue, opaque, hard capsule sealed with a clear band and marked with “SEL 25” in black ink. 60 0310-0625-60 28 0310-0625-28 Selumetinib Oral Granules Strength Description Capsules per Bottle NDC Number 5 mg Off‑white to light‑yellow free‑flowing oral granules contained within capsules. The capsules have a yellow cap and white body. The cap is printed with “sel 5” in black ink, and body is printed with a sprinkle capsule image indicating opening. 60 0310‑0635‑60 7.5 mg Off‑white to light‑yellow free‑flowing oral granules contained within capsules. The capsules have a pink cap and white body where the cap is printed with “sel 7.5” in black ink, and body is printed with a sprinkle capsule image indicating opening. 60 0310‑0640‑60 Storage KOSELUGO Capsules Store KOSELUGO capsules at 20°C to 25°C (68°F to 77°F) with excursions permitted to 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Dispense and store in the original bottle to protect from light and moisture. Do not remove desiccant. Keep the bottle tightly closed after first opening. KOSELUGO Oral Granules Store and transport KOSELUGO oral granules refrigerated at 2°C to 8°C (36°F to 46°F). After receipt, patients may store at room temperature 20°C to 25°C (68°F to 77°F). Do NOT exceed 30°C (86°F). KOSELUGO oral granules may clump together or stick to the capsule shell if exposed to high temperatures, which may lead to underdose. Dispense and store in the original bottle to protect from light and moisture. Do not remove desiccant. Keep the bottle tightly closed after first opening.

Patient information

Advise the patient to read the FDA-approved patient labeling (Patient Information and Instructions for Use). Left Ventricular Dysfunction Advise patients and caregivers that KOSELUGO can cause a reduction in LVEF and to immediately report any signs or symptoms of cardiomyopathy to their healthcare provider [see Warnings and Precautions (5.1) ] . Ocular Toxicity Advise patients and caregivers that KOSELUGO can cause ocular toxicity that can lead to blindness and to contact their healthcare provider if the patient experiences any changes in their vision [see Warnings and Precautions (5.2) ] . Gastrointestinal Toxicity Advise patients and caregivers that KOSELUGO can cause diarrhea, nausea, vomiting, and stomatitis and to contact their healthcare provider at the first sign of gastrointestinal toxicity [see Warnings and Precautions (5.3) ] . Skin Toxicity Advise patients and caregivers that KOSELUGO can cause serious skin toxicities and to contact their healthcare provider for severe skin changes [see Warnings and Precautions (5.4) ] . Increased Creatine Phosphokinase Advise patients and caregivers that KOSELUGO can cause increased CPK and rhabsomyolysis to report any signs and symptoms of muscle pain or weakness to their healthcare provider [see Warnings and Precautions (5.5) ] . Increased Vitamin E Levels and Increased Risk of Bleeding (KOSELUGO Capsules) Advise patients and caregivers to notify their healthcare provider if they are taking a supplement containing vitamin E, a vitamin-K antagonist or an anti-platelet agent [see Warnings and Precautions (5.6) ] . Embryo-Fetal Toxicity
• Advise pregnant women and females of reproductive potential of the potential risk to a fetus. Advise females of reproductive potential to inform their healthcare provider of a known or suspected pregnancy [see Warnings and Precautions (5.7) , Use in Specific Populations (8.1) ].
• Advise females of reproductive potential to use effective contraception during treatment with KOSELUGO and for 1 week after the last dose [see Use in Specific Populations (8.3) ] .
• Advise males with female partners of reproductive potential to use effective contraception during treatment with KOSELUGO and for 1 week after the last dose [see Use in Specific Populations (8.3) , Nonclinical Toxicology (13.1) ] . Lactation Advise women not to breastfeed during treatment with KOSELUGO and for 1 week after the last dose [see Use in Specific Populations (8.2) ] . Drug Interactions Advise patients and caregivers to inform their healthcare provider of all concomitant medications, including prescription medicines, over-the-counter drugs, vitamins, and herbal products. Inform patients to avoid St. John’s wort, grapefruit or grapefruit juice, and Seville orange while taking KOSELUGO [see Drug Interactions (7) ] . Dosing and Administration Inform patients and caregivers on how to take KOSELUGO and what to do for missed or vomited doses [see Dosage and Administration (2.1) ] . Distributed by: AstraZeneca Pharmaceuticals LP Wilmington, DE 19850 © AstraZeneca 20XX

Label text from the FDA structured product label by AstraZeneca Pharmaceuticals LP (revised May 26, 2026). Long sections are shortened; the complete label is on DailyMed.

Active ingredients

Selumetinib in 4 products

Koselugo NDC products (4)

NDC	Strength & form	Labeler	Type
0310-0610	Selumetinib 10 mg/1 Capsule	AstraZeneca Pharmaceuticals LP	NDA
0310-0625	Selumetinib 25 mg/1 Capsule	AstraZeneca Pharmaceuticals LP	NDA
0310-0635	Selumetinib 5 mg/1 Granule	AstraZeneca Pharmaceuticals LP	NDA
0310-0640	Selumetinib 7.5 mg/1 Granule	AstraZeneca Pharmaceuticals LP	NDA

Frequently asked questions

What is Koselugo used for?

What are the side effects of Koselugo?

Who makes Koselugo?

Koselugo is listed by 1 labeler in the FDA NDC directory, including AstraZeneca Pharmaceuticals LP.