Ganaxolone

Ganaxolone is a prescription medicine used to treat seizures associated with cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) in patients aged 2 years and older.

• Ganaxolone is available under the following different brand names: Ztalmy.

Common side effects of Ganaxolone include:

• drowsiness
• fever
• coughing (with or without mucus)
• runny or stuffy nose 
• sneezing
• sore throat
• lightheadedness
• drowsiness
• slurred speech
• shallow breathing
• slowed heart rate
• poor coordination  
• increased saliva
• itchy, watery, or red eyes
• postnasal drip
• headache
• sneezing 
• fatigue
• chills
• chest discomfort 
• influenza
• difficulty walking

Serious side effects of Ganaxolone include:

• hives 
• difficulty breathing 
• swelling of the face, lips, tongue, or throat
• dizziness

Rare side effects of Ganaxolone include:

• none 

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, coordination loss, unsteady, very stiff muscles, high fever, profuse sweating, or tremors.
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, lightheadedness, or passing out.

This is not a complete list of side effects and other serious side effects or health problems that may occur because of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Adult and pediatric dosage

Oral suspension

• 50 mg/mL (110mL/bottle)

Controlled substance schedule pending

Seizures

• Adult dosage
  • Dosage increased based on tolerability and no more frequently than every 7 days.
  • The dose must be taken with food.
  • Titration schedule (weight above 28 kg)
  • Days 1-7: 150 mg orally three times a day.
  • Days 8-14: 300 mg orally three times a day.
  • Days 15-21: 450 mg orally three times a day.
  • Days 22 and thereafter: 600 mg orally three times a day.
• Pediatric dosage
  • Dosage increased based on tolerability and no more frequently than every 7 days.
  • The dose must be taken with food.
  • Titration schedule (weighing 28 kg or below)
    • Days 1-7: 6 mg/kg orally three times a day
    • Days 8-14: 11 mg/kg orally three times a day
    • Days 15-21: 16 mg/kg orally three times a day
    • Days 22 and thereafter: 21 mg/kg orally three times a day
  • Titration schedule (weight above 28 kg)
    • Days 1-7: 150 mg orally three times a day.
    • Days 8-14: 300 mg orally three times a day.
    • Days 15-21: 450 mg orally three times a day.
    • Days 22 and thereafter: 600 mg orally three times a day.

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Ganaxolone has severe interactions with no other drugs.
• Ganaxolone has serious interactions with at least 37 other drugs.
• Ganaxolone has moderate interactions with at least 203 other drugs.
• Ganaxolone has minor interactions with at least 26 other drugs.

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all the products you use. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, health questions, or concerns.

Contraindications

• none

Effects of drug abuse

• dependence

Short-Term Effects

• See “What Are Side Effects Associated with Using Ganaxolone?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Ganaxolone?”

Cautions

• Somnolence and sedation observed early during treatment and are generally dose-related; caution if coadministered with CNS depressants; advise the patient not to drive or operate machinery until they have gained sufficient experience to gauge whether ganaxolone adversely affects their ability to drive
• Antiepileptic drugs may increase the risk of suicidal thoughts or behavior in patients taking these drugs for any indication; monitor for emergence or worsening of depression; if suicidal thoughts and behavior emerge during treatment, consider whether these symptoms may be related to the illness being treated
• Ganaxolone can be abused or lead to dependence
• Ganaxolone, like other antiepileptic drugs, should be withdrawn gradually owing to the risk of increased seizure frequency and status epilepticus; because of a serious adverse event, rapid discontinuation can be considered
• Drug interaction overview
  • CYP3A4 substrate.
  • CYP3A4 inducers.
    • Avoid coadministration with moderate or strong CYP3A4 inducers
    • If coadministration is unavoidable, consider increasing the Ganaxolone dose; however, do not exceed the maximum daily dose for weight
    • In patients on a stable Ganaxolone dosage who are initiating or increasing the dosages of enzyme-inducing antiepileptic drugs (eg, carbamazepine, phenytoin, phenobarbital, primidone), Ganaxolone dose may need to be increased (not to exceed maximum daily dose)
  • CYP3A4 inhibitors.
    • Not clinically significant
    • Coadministration with itraconazole, a strong CYP3A4 inhibitor, increased Ganaxolone AUC by 17% in healthy subjects (peak plasma concentration was unchanged)
    • Changes in Ganaxolone exposures when coadministered with strong, moderate, or weak CYP3A4 inhibitors are not expected to be clinically significant
  • CNS depressants and alcohol
• Caution
  • Coadministration with CNS depressants, including alcohol, may increase the risk of somnolence and sedation

Pregnancy and Lactation

• Data are unavailable regarding the use of drug in pregnant women to inform a drug-associated risk of adverse developmental outcomes
• Based on animal data, may cause fetal harm
• Encourage women who are taking ganaxolone during pregnancy to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry by calling the toll-free number 1-888-233-2334 or visiting www.aedpregnancyregistry.org/
• Lactation
  • Excreted in human milk.
  • Following a single oral dose of Ganaxolone (300 mg), Ganaxolone exposures (AUC0-24 hours) in human milk were approximately 4 times higher than those in maternal plasma, resulting in an estimated daily dose in the infant of below 1% of the maternal dose
  • Effects on milk production and breastfed infants are unknown
  • Consider the developmental and health benefits of breastfeeding along with the mother’s clinical need for Ganaxolone, and any potential adverse effects on the breastfed child from Ganaxolone, or the underlying maternal condition