Sonidegib

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Capsule, Oral:

Odomzo: 200 mg

Pharmacology

Mechanism of Action

Basal cell cancer is associated with mutations in Hedgehog pathway components. Hedgehog regulates cell growth and differentiation in embryogenesis; while generally not active in adult tissue, Hedgehog mutations associated with basal cell cancer can activate the pathway resulting in unrestricted proliferation of skin basal cells (Von Hoff, 2009). Sonidegib is a selective Hedgehog pathway inhibitor which binds to and inhibits Smoothened homologue (SMO), the transmembrane protein involved in Hedgehog signal transduction.

Pharmacokinetics/Pharmacodynamics

Absorption

<10%; AUC_inf and C_max are increased by 7.4- to 7.8-fold, respectively, when administered with a high-fat meal (~1,000 calories with 50% fat content)

Distribution

9,166 L

Metabolism

Primarily hepatic through CYP3A

Excretion

Feces (~70%); urine (30%)

Time to Peak

2 to 4 hours

Half-Life Elimination

~28 days

Protein Binding

>97%

Use in Specific Populations

Special Populations: Race

Following a single 200 mg dose, exposure (AUC_inf) is 1.7-fold higher in Japanese healthy subjects as compared to Western healthy subjects.

Use: Labeled Indications

Basal cell carcinoma, locally advanced: Treatment of adult patients with locally advanced basal cell carcinoma (BCC) that has recurred following surgery or radiation therapy, or those who are not candidates for surgery or radiation therapy.

Contraindications

There are no contraindications listed in the manufacturer's labeling.

Dosage and Administration

Dosing: Adult

Note: Verify pregnancy status of females of reproductive potential prior to therapy initiation. Measure serum creatine kinase (CK) levels and renal function tests in all patients prior to starting treatment.

Basal cell carcinoma, locally advanced: Oral: 200 mg once daily until disease progression or unacceptable toxicity (Migden 2015)

Missed doses: If a dose is missed, skip the missed dose and resume dosing with the next scheduled dose.

Dosing: Geriatric

Refer to adult dosing.

Dosing: Adjustment for Toxicity

Withhold treatment for any of the following (may resume at 200 mg daily upon resolution of toxicity):

Creatine kinase (CK) serum elevation between 2.5 and 10 times ULN (first occurrence) or between 2.5 and 5 times ULN (recurrent)

Musculoskeletal toxicity, severe or intolerable

Permanently discontinue therapy for:

CK serum elevation >2.5 times ULN with worsening renal function

CK serum elevation >10 times ULN

CK serum elevation >5 times ULN (recurrent)

Musculoskeletal toxicity, severe or intolerable (recurrent)

Administration

Oral: Administer on an empty stomach at least 1 hour before or 2 hours after a meal.

Storage

Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F).

Drug Interactions

Clofazimine: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Conivaptan: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

CYP3A4 Inducers (Moderate): May decrease the serum concentration of Sonidegib. Avoid combination

CYP3A4 Inducers (Strong): May decrease the serum concentration of Sonidegib. Avoid combination

CYP3A4 Inhibitors (Moderate): May increase the serum concentration of Sonidegib. Management: Avoid concomitant use of sonidegib and moderate CYP3A4 inhibitors when possible. When concomitant use cannot be avoided, limit CYP3A4 inhibitor use to less than 14 days and monitor for sonidegib toxicity (particularly musculoskeletal adverse reactions). Consider therapy modification

CYP3A4 Inhibitors (Strong): May increase the serum concentration of Sonidegib. Avoid combination

Deferasirox: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Erdafitinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Erdafitinib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Fosaprepitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Fusidic Acid (Systemic): May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Idelalisib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Ivosidenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Larotrectinib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Palbociclib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Sarilumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Siltuximab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Simeprevir: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Stiripentol: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Use of stiripentol with CYP3A4 substrates that are considered to have a narrow therapeutic index should be avoided due to the increased risk for adverse effects and toxicity. Any CYP3A4 substrate used with stiripentol requires closer monitoring. Consider therapy modification

Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Adverse Reactions

>10%:

Central nervous system: Fatigue (41%), headache (15%), pain (14%)

Dermatologic: Alopecia (53%)

Endocrine & metabolic: Hyperglycemia (51%), weight loss (30%), increased serum ALT (19%), increased serum AST (19%), increased amylase (16%)

Gastrointestinal: Dysgeusia (46%), increased serum lipase (43%), nausea (39%), diarrhea (32%), decreased appetite (23%), abdominal pain (18%), vomiting (11%)

Hematologic & oncologic: Anemia (32%), lymphocytopenia (28%, grades 3/4: 3%)

Neuromuscular & skeletal: Increased creatine phosphokinase (61%, grades 3/4: 8%), muscle spasm (54%; grade 3: 3%), musculoskeletal pain (32%, grade 3: 1%), myalgia (19%)

Renal: Increased serum creatinine (92%)

1% to 10%:

Dermatologic: Pruritus (10%)

<1%, postmarketing, and/or case reports: Amenorrhea, rhabdomyolysis

Warnings/Precautions

Concerns related to adverse effects:

• Amenorrhea: Amenorrhea lasting for at least 18 months was observed in women of reproductive potential.
• Musculoskeletal toxicity: Musculoskeletal toxicity occurred in more than two-thirds of patients treated with sonidegib (including grade 3 and 4 events). Muscle spasms, musculoskeletal pain, and myalgia were the most frequently reported musculoskeletal adverse reactions. Increased serum creatine kinase (CK) levels were also commonly observed (some events were grade 3 or 4); CK elevations were usually preceded by musculoskeletal pain and myalgia. When CK elevations were grade 2 or higher, the median time to symptom onset was ~13 weeks (range: 2 to 39 weeks), and the median time to resolution (to ≤ grade 1) was 12 days. More than one-quarter of patients required medical management for musculoskeletal toxicity (eg, magnesium supplementation, muscle relaxants, and analgesics/opioids); several patients required intravenous hydration or hospitalization. Rhabdomyolysis was observed in 1 patient in clinical trials (at a dose higher than the FDA-approved dose). Monitor serum CK levels and serum creatinine at baseline and periodically during therapy (more frequently if muscle symptoms are reported or if clinically indicated). Advise patients to promptly report new unexplained muscle pain, tenderness, or weakness (either occurring during therapy or persisting after discontinuation). May require therapy interruption or discontinuation.

Disease-related concerns:

• Renal impairment: Increased serum creatinine was observed in the majority of patients receiving sonidegib, although the measurement remained within the normal range in more than 75% of patients. While dosage adjustment is not required in patients with renal impairment, monitor serum creatinine at baseline and periodically, particularly if patients present with musculoskeletal toxicity.

Concurrent drug therapy issues:

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Special populations:

• Pediatric: Premature fusion of the epiphyses has been reported in pediatric patients exposed to sonidegib and other Hedgehog pathway inhibitors; the fusion progressed after discontinuation in some cases following use of other Hedgehog pathway inhibitors. Sonidegib is not indicated for use in pediatric patients.
• Pregnancy: [US Boxed Warning]: Sonidegib can cause embryo-fetal death or severe birth defects when administered to a pregnant woman. Sonidegib is embryotoxic, fetotoxic, and teratogenic in animals. Verify the pregnancy status of females of reproductive potential prior to initiating therapy. Advise females of reproductive potential to use effective contraception during treatment with sonidegib and for at least 20 months after the last dose. Advise males of the potential risk of exposure through semen and to use condoms with a pregnant partner or a female partner of reproductive potential during treatment with sonidegib and for at least 8 months after the last dose.

Other warnings/precautions:

• Blood donations: Advise patients not to donate blood or blood products during sonidegib treatment and for at least 20 months after the last sonidegib dose.
• Conversion: One 200 mg sonidegib capsule is equivalent to 281 mg of the diphosphate salt of sonidegib.
• Sperm donations: It is not known if sonidegib is present in semen. Advise patients not to donate sperm during sonidegib treatment and for at least 8 months after the last sonidegib dose.

Monitoring Parameters

Serum creatine kinase (CK) and serum creatinine (baseline, periodically during treatment, and at least weekly with musculoskeletal toxicity and CK elevations >2.5 times ULN until resolution), liver function, pregnancy status, signs/symptoms of musculoskeletal toxicity.

Pregnancy

Pregnancy Considerations

[US Boxed Warning]: Sonidegib can cause embryo-fetal death or severe birth defects when administered to a pregnant woman. Sonidegib is embryotoxic, fetotoxic, and teratogenic in animals. Verify the pregnancy status of females of reproductive potential prior to initiating therapy. Advise females of reproductive potential to use effective contraception during treatment with sonidegib and for at least 20 months after the last dose. Advise males of the potential risk of exposure through semen and to use condoms with a pregnant partner or a female partner of reproductive potential during treatment with sonidegib and for at least 8 months after the last dose. It is not known if sonidegib is present in semen. Males with female partners of reproductive potential should use condoms even following a vasectomy. Advise male patients not to donate sperm during sonidegib treatment and for at least 8 months after the last sonidegib dose.

Health care providers should notify the manufacturer of pregnancies which may occur following exposure to sonidegib (800-406-7984).

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
• Patient may experience hair loss, change in taste, abdominal pain, nausea, vomiting, diarrhea, weight loss, lack or appetite, itching, or headache. Have patient report immediately to prescriber signs of high blood sugar (confusion, fatigue, increased thirst, increased hunger, passing a lot of urine, flushing, fast breathing, or breath that smells like fruit), severe loss of strength and energy, chills, sore throat, muscle spasms, muscle pain, dark urine, or change in amount of urine passed (HCAHPS).
• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.