Each tablet of FIRDAPSE includes 18.98 mg of amifampridine phosphate that is the equivalent to 10 mg of amifampridine freebase as found in 3,4-diaminopyridine freebase (often called 3,4-DAP or DAP), which was available to some LEMS patients through a compassionate-use program for years.
FIRDAPSE utilizes a phosphate salt in the amifampridine structure to stabilize the amifampridine molecule, allowing FIRDAPSE to be stored at room temperature for long periods of time without losing potency and keeping it safe for others.
When FIRDAPSE is taken, the drug quickly separates into amifampridine (3,4-DAP) freebase and phosphate salt ions in your bloodstream.
Each tablet of FIRDAPSE includes 1.5 mg of phosphate, an essential nutrient that the human body needs. The US Centers for Disease Control and Prevention recommends a 700 mg/day allowance of phosphorus; a maximum daily dose of FIRDAPSE provides only 12 mg per day.
Yes—FIRDAPSE also uses inactive ingredients to help form a tablet that includes calcium stearate, colloidal silicon dioxide, and microcrystalline cellulose.
All of these inactive ingredients are classified by the FDA as “generally recognized as safe” (GRAS) for this use and are considered hypoallergenic. Additionally, FIRDAPSE is gluten free.
The only other approved product that contains amifampridine (approved for an indication distinct and separate from that of FIRDAPSE) has 10 mg of 3,4-DAP freebase but also contains inactive ingredients such as colloidal silicon dioxide, dibasic calcium phosphate dihydrate, magnesium stearate, microcrystalline cellulose, and sodium starch glycolate.
FIRDAPSE is a prescription medicine used to treat adults 17 years of age or older with Lambert-Eaton myasthenic syndrome (LEMS). The safety and efficacy of FIRDAPSE in patients under the age of 17 has not been established.
What is the most important information I should know about FIRDAPSE?
Stop taking FIRDAPSE and call your doctor right away if you have a seizure while taking FIRDAPSE.
Do not take FIRDAPSE if you:
Before you take FIRDAPSE, tell your doctor about all of your medical conditions, including if you:
Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
How should I take FIRDAPSE?
What are the possible side effects of FIRDAPSE?
FIRDAPSE may cause serious side effects, including:
Tell your doctor if you have any side effect that bothers you or that does not go away.
These are not all the possible side effects of FIRDAPSE.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
How should I store FIRDAPSE?
Keep FIRDAPSE and all medicines out of the reach of children.
If you would like more information, ask your doctor or pharmacist for additional information about FIRDAPSE.
The active ingredient in FIRDAPSE is amifampridine phosphate. Inactive ingredients are calcium stearate, colloidal silicon dioxide, and microcrystalline cellulose.
Please see full Prescribing Information for additional Important Safety Information.
FIRDAPSE is a prescription medicine used to treat adults 17 years of age or older with Lambert-Eaton myasthenic syndrome (LEMS). The safety and efficacy of FIRDAPSE in patients under the age of 17 has not been established.
What is the most important information I should know about FIRDAPSE?
Stop taking FIRDAPSE and call your doctor right away if you have a seizure while taking FIRDAPSE.
Do not take FIRDAPSE if you:
Before you take FIRDAPSE, tell your doctor about all of your medical conditions, including if you:
Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
How should I take FIRDAPSE?
What are the possible side effects of FIRDAPSE?
FIRDAPSE may cause serious side effects, including:
Tell your doctor if you have any side effect that bothers you or that does not go away.
These are not all the possible side effects of FIRDAPSE.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
How should I store FIRDAPSE?
Keep FIRDAPSE and all medicines out of the reach of children.
If you would like more information, ask your doctor or pharmacist for additional information about FIRDAPSE.
The active ingredient in FIRDAPSE is amifampridine phosphate. Inactive ingredients are calcium stearate, colloidal silicon dioxide, and microcrystalline cellulose.
Please see full Prescribing Information for additional Important Safety Information.