Firdapse amifampridine phosphate 10 mg Tablet, 240-count — NDC 69616-211-03 (Billing 69616-0211-03)
This is a package of 240 tablets of Firdapse amifampridine phosphate 10 mg Tablet from Catalyst Pharmaceuticals, Inc., marketed since Jan 2019 and currently FDA-listed. It is the main listing for this product, which comes in 3 package sizes.
NDC database record
One package, one record: these facts belong to NDC 69616-211-03 alone.
- Record
- FDA NDC Directory package listing · Human prescription drug
- Code segments
- 69616 labeler · 211 product · 03 package
- Package marketed since
- Jan 7, 2019
- Sample package
- No — commercial package
- Listing certified through
- Dec 31, 2027
- Billing quantity
- 240 EA per package
- Barcode (UPC-A, from the NDC)
- 3 6961621103 4
- Medicaid fills, this package
- 217 prescriptions in the last four reported quarters
- FDA record last changed
- Jul 24, 2026
Identity & classification
Regulatory identifiers FDA, NLM and CMS codes for this package
Drug-database identifiers Medi-Span GPI and First Databank GCN / HICL / AHFS classification
- GSN (GCN sequence number): 066227
- GCN: 28457
- GPI-14 (Medi-Span): 76000012100320
- HICL (First Databank): 036930
- AHFS class code: 12:04.00.00
- RxCUI (RxNorm): 2106343
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 8, 2026
- FDA label on DailyMed · label index refreshed Oct 8, 2026
- RxNorm (NLM RxNav) · catalog refreshed Oct 8, 2026
- Medi-Span GPI (licensed)
- First Databank (licensed) · refreshed Oct 8, 2026
RxNorm drug class
This medicine belongs to the Potassium Channel Blocker class.
Where does this data come from?
- RxClass (NLM) · catalog refreshed Oct 8, 2026
Clinical
Patient education
Supplement & herbal interactions
Some supplements/herbs that may interact with Amifampridine Phosphate — tap one for details:
Where does this data come from?
- MedlinePlus (NLM) · refreshed Oct 8, 2026
- FDA label on DailyMed · label index refreshed Oct 8, 2026
Ask a licensed pharmacist directly — free, answered by our team.
Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per each | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | $249.23 | $59,815.49 / 240 tablets |
| Medicare drug plans payPart D · Q2 2026 | $266.15 | $63,875.81 / 240 tablets |
Where does this data come from?
- CMS NADAC weekly file
- CMS ASP pricing files · refreshed Sep 20, 2026
- CMS Medicaid State Drug Utilization Data · through Q1 2026
- CMS Part D plan pricing files · refreshed Sep 24, 2026
- VA National Acquisition Center price file
Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Marketing end | Status |
|---|---|---|---|---|
| 69616-0211-03 You're viewing this Main listing | 240 TABLET in 1 BOTTLE, PLASTIC | 2019-01-07 | — | Active |
| 69616-0211-06 69616-211-06 | 12 BLISTER PACK in 1 CARTON / 10 TABLET in 1 BLISTER PACK | 2019-01-07 | — | Active |
| 69616-0211-08 69616-211-08 | 60 TABLET in 1 BOTTLE, PLASTIC | 2019-01-07 | — | Active |
In Medicaid, this is the most-dispensed pack of this product — about 88% of fills over the last four reported quarters. See all packs ↓
Pack size FAQ
What quantity is in this package?
How does this package differ from NDC 69616-0211-08?
What NDC number is used to bill for this package of Firdapse amifampridine phosphate 10 mg Tablet?
Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Firdapse 10 mgthis 69616-0211-03 | Catalyst | 240 tablets | — | — | FDA listed | — |
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 8, 2026
- FDA Orange Book · refreshed Oct 3, 2026
- CMS NADAC weekly file
Availability & generic status
We did not find an FDA-approved generic match for this exact strength, form and route. Patent/protection dates below may affect future generic timing.
Why the date isn’t exact: Generic timing can change because patents may be challenged, settled, licensed, added, removed, or worked around with a narrower label — and FDA approval does not always mean a pharmacy can get the generic today.
🛈 What do these terms mean?
- Patent
- Legal protection listed in the Orange Book that may delay generic approval or launch. Issued by the U.S. Patent & Trademark Office.
- Substance patent
- Covers the active drug molecule itself — the hardest to design around. A generic generally can’t launch until it expires.
- Formulation (product) patent
- Covers a specific formulation or dosage form. A generic can sometimes work around it with a different formulation.
- Method-of-use patent
- A patent covering one specific approved use of the drug — not necessarily the whole molecule. A generic can sometimes launch with a “skinny label” that carves out the protected use and keeps the others.
- Skinny label
- A generic label that omits a still-patented use when the FDA allows it — letting a generic reach the market for the unprotected uses.
- Exclusivity
- FDA-granted marketing protection, separate from patents — e.g. 5-yr new chemical entity, 7-yr orphan drug, or a +6-month pediatric extension.
- Paragraph IV
- A generic applicant’s formal challenge to a listed patent. It can potentially lead to earlier generic entry, but often involves litigation or a settlement.
- RLD / RS
- Reference Listed Drug — the brand product the FDA uses as the reference for generic applications. Reference Standard — the product the FDA expects generics to compare against in bioequivalence testing.
- TE / AB rating
- FDA therapeutic-equivalence rating. An AB rating generally means the FDA considers a generic therapeutically equivalent to — and substitutable for — the brand.
- LOE (loss of exclusivity)
- The latest patent or exclusivity currently listed — the loss-of-exclusivity / latest-listed-protection date shown on this page. Paragraph-IV challenges and settlements can move the real date earlier; FDA approval and a manufacturer’s decision to market can move it later.
Built from the FDA Orange Book. The bars above are scaled to each protection’s expiry; the red LOE marker is the last one to lapse.
| Patent | Type | Use code | Expires |
|---|---|---|---|
| US 11274332 ↗ | Method of use | U-2956 | Jun 29, 2032 |
| US 11274331 ↗ | Method of use | U-2956 | Jun 29, 2032 |
| US 10793893 ↗ | Method of use | U-2956 | May 26, 2034 |
| US 11268128 ↗ | Method of use | U-2956 | Jun 29, 2032 |
| US 11060128 ↗ | Method of use | U-2956 | Jun 29, 2032 |
| US 10626088 ↗ | Drug product | — | Feb 25, 2037 |
| Code | What it grants | Expires |
|---|---|---|
| ODE-553 | Orphan Drug Exclusivity (7-year) | Sep 29, 2029 |
Is there a generic version of FIRDAPSE 10 MG TABLET?
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Where does this data come from?
- FDA Orange Book · refreshed Oct 3, 2026
What it looks like
Where does this data come from?
- FDA label on DailyMed · label index refreshed Oct 8, 2026
Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII 776XM7047L
Calcium stearate is a white powder derived from stearic acid and calcium. It works as a lubricant and glidant to help the medicine flow smoothly during manufacturing and prevent ingredients from sticking to equipment.
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UNII OP1R32D61U
Microcrystalline cellulose is a purified form of cellulose, a natural fiber from plant sources. It acts as a binder and filler in tablets and capsules, helping hold ingredients together and give the medicine its shape and size.
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UNII ETJ7Z6XBU4
Silicon dioxide is a naturally occurring mineral used as a glidant and anti-caking agent. It helps powder ingredients flow smoothly and prevents clumping during manufacturing and storage.
3 inactive ingredients listed in the exact product block matched to this NDC.
Where does this data come from?
ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.- FDA label on DailyMed · label index refreshed Oct 8, 2026
- FDA openFDA NDC Directory · synced Oct 8, 2026
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Manufacturer & labeler
More NDCs from Catalyst Pharmaceuticals, Inc. labeler code 69616
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 8, 2026
- Drugs@FDA
Full prescribing information FDA SPL
🎯 Indications and Usage ▾
1 INDICATIONS AND USAGE FIRDAPSE ® is indicated for the treatment of Lambert-Eaton myasthenic syndrome (LEMS) in adults and pediatric patients 6 years of age and older. FIRDAPSE is a potassium channel blocker indicated for the treatment of Lambert-Eaton myasthenic syndrome (LEMS) in adults and pediatric patients 6 years of age and older. ( 1 )
⏱️ Dosage and Administration ▾
2 DOSAGE AND ADMINISTRATION Administer orally in divided doses (3 to 5 times daily). ( 2.1 ) The recommended starting dosage for adults (any weight) and pediatric patients weighing 45 kg or more is 15 mg to 30 mg daily, in divided doses. ( 2.1 ) Dosage can be increased by 5 mg daily every 3 to 4 days.
( 2.1 ) The maximum single dose is 20 mg. ( 2.1 ) Dosage is not to exceed a maximum of 100 mg daily. ( 2.1 ) The recommended starting dosage for pediatric patients weighing less than 45 kg is 5 mg to 15 mg daily, in divided doses.
( 2.1 ) Dosage can be increased by 2.5 mg daily every 3 to 4 days. ( 2.1 ) The maximum single dose is 10 mg. ( 2.1 ) Dosage is not to exceed a maximum of 50 mg daily.
( 2.1 ) The recommended starting dosage for adult and pediatric patients with renal impairment, hepatic impairment, and in known N-acetyltransferase 2 (NAT2) poor metabolizers is the lowest recommended initial daily dosage ( 2.1 , 2.2 , 2.3 , 2.4 ) For patients with a dosage adjustment of less than 5 mg increments, or who have difficulty swallowing, or require feeding tube, a l mg/mL suspension can be prepared. ( 2.5 )
2.1Dosage Information The recommended oral dosage of FIRDAPSE for adults and pediatric patients 6 years of age and older is included in Table 1 . For pediatric patients, the recommended dosing regimen is dependent on body weight. Dosage should be increased every 3 to 4 days based on clinical response and tolerability.
Titration increments should not exceed those shown in Table 1 . Table 1: Recommended Oral Dosage for the Treatment of LEMS in Adults and Pediatric Patients 6 Years of Age and Older * See Dosage and Administration ( 2.5 ) for a method to achieve these doses Age and Body Weight Initial Daily Dosage * Titration Regimen Maximum Single Dose Maximum Total Daily Maintenance Dosage Adults (any weight) Pediatric patients weighing 45 kg or more 15 mg to 30 mg daily, in 3 to 5 divided doses Increase total daily dosage by 5 mg every 3 or 4 days 20 mg 100 mg Given in divided doses Pediatric patients weighing less than 45 kg 5 mg to 15 mg daily, in 3 to 5 divided doses Increase total daily dosage by 2.5 mg every 3 or 4 days 10 mg 50 mg Given in divided doses Missed Dose If a dose is missed, patients should not take double or extra doses.
2.2Patients with Renal Impairment The recommended starting dosage of FIRDAPSE in patients with renal impairment [creatinine clearance (CLcr) 15 to 90 mL/min] is the lowest recommended initial daily dosage (i.e., 15 mg daily for pediatric patients weighing 45 kg or more and for adults, and 5 mg daily for pediatric patients weighing less than 45 kg) taken orally in divided doses. No dosage recommendation for FIRDAPSE can be made for patients with end-stage renal disease [see Dosage and Administration ( 2.1 ), Use in Specific Populations ( 8.6 ), and Clinical Pharmacology ( 12.3 )].
2.3Patients with Hepatic Impairment The recommended starting dosage of FIRDAPSE in patients with any degree of hepatic impairment is the lowest recommended initial daily dosage (i.e., 15 mg daily for pediatric patients weighing 45 kg or more and for adults, and 5 mg daily for pediatric patients weighting less than 45 kg) taken orally in divided doses [see Dosage and Administration ( 2.1 ), Use in Specific Populations ( 8.7 ), and Clinical Pharmacology ( 12.3 )].
2.4Known N-acetyltransferase 2 (NAT2) Poor Metabolizers The recommended starting dosage of FIRDAPSE in known N-acetyltransferase 2 (NAT2) poor metabolizers is the lowest recommended initial daily dosage (i.e., 15 mg daily for pediatric patients weighing 45 kg or more and for adults, and 5 mg daily for pediatric patients weighing less than 45 kg) taken orally in divided doses [see Dosage and Administration ( 2.1 ), Use in Specific Populations ( 8.8 ), and Clinical Pharmacology ( 12.5 )].
2.5Administration Instructions FIRDAPSE can be taken without regard to food. Preparation of a 1mg/mL Suspension (see the Instructions for Use for full instructions on ho… [Excerpted — this section continues on DailyMed.]
💊 Dosage Forms and Strengths ▾
3 DOSAGE FORMS AND STRENGTHS FIRDAPSE tablets contain 10 mg amifampridine and are white to off-white, round, and functionally scored. Each tablet is debossed on the non-scored side with “CATALYST” and on the scored side with “211” above the score and “10” below the score. Tablets: 10 mg, functionally scored. ( 3 )
⛔ Contraindications ▾
4 CONTRAINDICATIONS FIRDAPSE is contraindicated in patients with: A history of seizures [see Warnings and Precautions ( 5.1 )] Hypersensitivity to amifampridine phosphate or another aminopyridine [see Warnings and Precautions ( 5.2 )] FIRDAPSE is contraindicated in patients with: A history of seizures ( 4 ) Hypersensitivity to amifampridine or another aminopyridine ( 4 )
⚠️ Warnings and Cautions ▾
5 WARNINGS AND PRECAUTIONS Seizures: FIRDAPSE can cause seizures. Consider discontinuation or dose-reduction of FIRDAPSE in patients who have a seizure while on treatment. ( 5.1 ) Hypersensitivity reactions: If a hypersensitivity reaction such as anaphylaxis occurs, FIRDAPSE should be discontinued and appropriate therapy initiated. ( 5.2 )
5.1Seizures FIRDAPSE can cause seizures. Seizures have been observed in patients without a history of seizures taking FIRDAPSE at the recommended doses, at various times after initiation of treatment, at an incidence of approximately 2%. Many of the patients were taking medications or had comorbid medical conditions that may have lowered the seizure threshold [see Drug Interactions ( 7.1 )].
Seizures may be dose-dependent. Consider discontinuation or dose-reduction of FIRDAPSE in patients who have a seizure while on treatment. FIRDAPSE is contraindicated in patients with a history of seizures.
5.2Hypersensitivity In clinical trials, hypersensitivity reactions and anaphylaxis associated with FIRDAPSE administration have not been reported. Anaphylaxis has been reported in patients taking another aminopyridine; therefore, it may occur with FIRDAPSE. If anaphylaxis occurs, administration of FIRDAPSE should be discontinued and appropriate therapy initiated.
🤒 Adverse Reactions ▾
6 ADVERSE REACTIONS The following serious adverse reactions are described elsewhere in the labeling: Seizures [see Warnings and Precautions ( 5.1 )] Hypersensitivity [see Warnings and Precautions ( 5.2 )] The most common (> 10%) adverse reactions are: paresthesia, upper respiratory tract infection, abdominal pain, nausea, diarrhea, headache, elevated liver enzymes, back pain, hypertension, and muscle spasms. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Catalyst Pharmaceuticals at 1-844-347-3277 (1-844-FIRDAPSE) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .
6.1Clinical Trials Experience Adults 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. In controlled and uncontrolled clinical trials (Study 1 and 2) in patients with LEMS [see Clinical Studies ( 14 )] , 63 patients were treated with FIRDAPSE, including 40 patients treated for more than 6 months, and 39 patients treated for more than 12 months.
In an expanded access program, 139 patients with LEMS were treated with FIRDAPSE, including 102 patients treated for more than 6 months, 77 patients treated for more than 12 months, and 53 patients treated for more than 18 months. In the expanded access program, patients were treated with FIRDAPSE with up to 100 mg daily in divided doses. Study 1 was a double-blind, placebo-controlled, randomized discontinuation study in adults with LEMS.
Following an initial open- label run-in phase (up to 90 days), patients were randomized to either continue FIRDAPSE treatment or transition to placebo, for a 14-day double-blind phase. Following final assessments, patients were allowed to resume FIRDAPSE treatment for up to 2 years (open-label long-term safety phase of the study). During the open-label run-in phase of Study 1, 53 patients received FIRDAPSE for an average of 81 days at a mean daily dosage of 50.5 mg/day.
The mean patient age was 52.1 years and 66% were female. There were 42 patients who had no prior exposure to FIRDAPSE at the initiation of this study. Table 2 shows adverse reactions with an incidence of 5% or greater occurring in the 42 LEMS patients newly initiated on treatment with FIRDAPSE during the run-in phase of the study.
Table 2. Adverse Reactions in ≥5% of LEMS Patients Newly Treated with FIRDAPSE in Study 1 *Includes paresthesia, oral paresthesia, oral hypoesthesia **Includes elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and gamma-glutamyl transferase (GGT) Adverse Reaction FIRDAPSE N=42 % Paresthesia* 62 Upper respiratory tract infection 33 Abdominal pain 14 Nausea 14 Diarrhea 14 Headache 14 Elevated liver enzymes** 14 Back pain 14 Hypertension 12 Muscle spasms 12 Dizziness 10 Asthenia 10 Muscular weakness 10 Pain in extremity 10 Cataract 10 Constipation 7 Bronchitis 7 Fall 7 Lymphadenopathy 7 Other Adverse Reactions In the overall population treated in Study 1 (n=53), including the double-blind phase and the 2-year open-label long-term safety phase, additional adverse reactions occurring in at least 5% of the patients included: dyspnea, urinary tract infection, gastroesophageal reflux, insomnia, peripheral edema, pyrexia, viral infection, blood creatine phosphokinase increase, depression, erythema, hypercholesterolemia, and influenza.
These patients received a mean daily dosage of 66 mg of FIRDAPSE. Pediatrics Safety of FIRDAPSE was evaluated in pediatric patients in an expanded access program, where 21 pediatric patients received FIRDAPSE for at least 1 year. Adverse reactions reported in pediatric patients were similar to those seen in adult patients, with the exception of clinically significant weight loss in two pediatric patients at doses of 60 mg per day and higher.
🔄 Drug Interactions ▾
7 DRUG INTERACTIONS Drugs that lower seizure threshold: Concomitant use may lead to an increased risk of seizures. ( 7.1 ) Drugs with cholinergic effects (e.g., direct or indirect cholinesterase inhibitors): Concomitant use may increase the cholinergic effects of FIRDAPSE and of those drugs and increase the risk of adverse reactions. ( 7.2 )
7.1Drugs that Lower Seizure Threshold The concomitant use of FIRDAPSE and drugs that lower seizure threshold may lead to an increased risk of seizures [see Warnings and Precautions ( 5.1 )]. The decision to administer FIRDAPSE concomitantly with drugs that lower the seizure threshold should be carefully considered in light of the severity of the associated risks.
7.2Drugs with Cholinergic Effects The concomitant use of FIRDAPSE and drugs with cholinergic effects (e.g., direct or indirect cholinesterase inhibitors) may increase the cholinergic effects of FIRDAPSE and of those drugs and increase the risk of adverse reactions.
👥 Use in Specific Populations ▾
8 USE IN SPECIFIC POPULATIONS Pregnancy: Based on animal data, may cause fetal harm. ( 8.1 )
8.1Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to FIRDAPSE during pregnancy. Physicians are encouraged to enroll pregnant patients, or pregnant women may register themselves in the registry by calling 855- 212-5856 (toll-free), using the Fax number 877-867-1874 (toll-free), by contacting the Pregnancy Coordinating Center at [email protected], or by visiting the study website www.firdapsepregnancystudy.com. Risk Summary There are no data on the developmental risk associated with the use of FIRDAPSE in pregnant women.
In animal studies, administration of amifampridine phosphate to rats during pregnancy and lactation resulted in developmental toxicity (increase in stillbirths and pup deaths, reduced pup weight, and delayed sexual development) at doses associated with maternal plasma drug levels lower than therapeutic drug levels (see Animal Data ). In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown.
Data Animal Data Oral administration of amifampridine phosphate (0, 7.5, 22.5, or 75 mg/kg/day) to female rats prior to and during mating and continuing throughout organogenesis produced no adverse effects on embryofetal development. The highest dose tested is approximately 4 times the maximum recommended human dose (MRHD) of amifampridine (100 mg/day) on a body surface area (mg/m 2 ) basis. Oral administration of amifampridine phosphate (0, 9, 30, or 57 mg/kg/day) to pregnant rabbits throughout organogenesis produced no adverse effects on embryofetal development.
The highest dose tested is approximately 6 times the MRHD of amifampridine on a body surface area (mg/m 2 ) basis. Oral administration of amifampridine phosphate (0, 7.5, 22.5, or 75 mg/kg/day) to female rats throughout pregnancy and lactation resulted in an increase in stillbirths and pup deaths, reduced pup weight, and delayed sexual development in female pups at the mid and high doses tested. The no-effect dose (7.5 mg/kg/day amifampridine phosphate) for adverse developmental effects is associated with a plasma amifampridine exposure (AUC) less than that in humans at the MRHD of amifampridine.
8.2Lactation Risk Summary There are no data on the presence of FIRDAPSE in human milk, the effects on the breastfed infant, or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for FIRDAPSE and any potential adverse effects on the breastfed infant from FIRDAPSE or from the underlying maternal condition. In lactating rat, amifampridine was excreted in milk and reached levels similar to those in maternal plasma.
8.4Pediatric Use Safety and effectiveness of FIRDAPSE for the treatment of LEMS have been established in pediatric patients 6 years of age and older. Use of FIRDAPSE for this indication is supported by evidence from adequate and well-controlled studies of FIRDAPSE in adults with LEMS, pharmacokinetic data in adult patients, pharmacokinetic modeling and simulation to identify the dosing regimen in pediatric patients, and safety data from pediatric patients aged 6 years and older [see Adverse Reactions ( 6.1 ), Clinical Pharmacology ( 12.3 ), and Clinical Studies ( 14 )] .
Safety and effectiveness in pediatric patients below the age of 6 years have not been established.
8.5Geriatric Use Clinical studies of FIRDAPSE did not include a sufficient number of subjects aged 65 and over (19 of 63 patients in Studies 1 and 2) to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the el… [Excerpted — this section continues on DailyMed.]
🤰 Pregnancy ▾
8.1Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to FIRDAPSE during pregnancy. Physicians are encouraged to enroll pregnant patients, or pregnant women may register themselves in the registry by calling 855- 212-5856 (toll-free), using the Fax number 877-867-1874 (toll-free), by contacting the Pregnancy Coordinating Center at [email protected], or by visiting the study website www.firdapsepregnancystudy.com. Risk Summary There are no data on the developmental risk associated with the use of FIRDAPSE in pregnant women.
In animal studies, administration of amifampridine phosphate to rats during pregnancy and lactation resulted in developmental toxicity (increase in stillbirths and pup deaths, reduced pup weight, and delayed sexual development) at doses associated with maternal plasma drug levels lower than therapeutic drug levels (see Animal Data ). In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown.
Data Animal Data Oral administration of amifampridine phosphate (0, 7.5, 22.5, or 75 mg/kg/day) to female rats prior to and during mating and continuing throughout organogenesis produced no adverse effects on embryofetal development. The highest dose tested is approximately 4 times the maximum recommended human dose (MRHD) of amifampridine (100 mg/day) on a body surface area (mg/m 2 ) basis. Oral administration of amifampridine phosphate (0, 9, 30, or 57 mg/kg/day) to pregnant rabbits throughout organogenesis produced no adverse effects on embryofetal development.
The highest dose tested is approximately 6 times the MRHD of amifampridine on a body surface area (mg/m 2 ) basis. Oral administration of amifampridine phosphate (0, 7.5, 22.5, or 75 mg/kg/day) to female rats throughout pregnancy and lactation resulted in an increase in stillbirths and pup deaths, reduced pup weight, and delayed sexual development in female pups at the mid and high doses tested. The no-effect dose (7.5 mg/kg/day amifampridine phosphate) for adverse developmental effects is associated with a plasma amifampridine exposure (AUC) less than that in humans at the MRHD of amifampridine.
🧒 Pediatric Use ▾
8.4Pediatric Use Safety and effectiveness of FIRDAPSE for the treatment of LEMS have been established in pediatric patients 6 years of age and older. Use of FIRDAPSE for this indication is supported by evidence from adequate and well-controlled studies of FIRDAPSE in adults with LEMS, pharmacokinetic data in adult patients, pharmacokinetic modeling and simulation to identify the dosing regimen in pediatric patients, and safety data from pediatric patients aged 6 years and older [see Adverse Reactions ( 6.1 ), Clinical Pharmacology ( 12.3 ), and Clinical Studies ( 14 )] .
Safety and effectiveness in pediatric patients below the age of 6 years have not been established.
🧓 Geriatric Use ▾
8.5Geriatric Use Clinical studies of FIRDAPSE did not include a sufficient number of subjects aged 65 and over (19 of 63 patients in Studies 1 and 2) to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy [see Dosage and Administration ( 2.2 , 2.3 ) and Drug Interactions ( 7.1 , 7.2 )] .
🆘 Overdosage ▾
10 OVERDOSAGE Overdose with FIRDAPSE was not reported during clinical studies. In a case report, a 65-year-old patient with LEMS inadvertently received a total daily amifampridine dose of 360 mg/day (approximately 4 times the maximum recommended total daily dose) and was hospitalized for general weakness, paresthesia, nausea, vomiting, and palpitations. The patient developed convulsions and paroxysmal supraventricular tachycardia, and four days after admission, experienced cardiac arrest.
The patient was resuscitated and ultimately recovered following withdrawal of amifampridine. Patients with suspected overdose with FIRDAPSE should be monitored for signs or symptoms of exaggerated FIRDAPSE adverse reactions or effects, and appropriate symptomatic treatment instituted immediately.
🧬 Clinical Pharmacology ▾
12 CLINICAL PHARMACOLOGY
12.1Mechanism of Action The mechanism by which amifampridine exerts its therapeutic effect in LEMS patients has not been fully elucidated. Amifampridine is a broad-spectrum potassium channel blocker.
12.2Pharmacodynamics The effect of FIRDAPSE on QTc interval prolongation was studied in a double blind, randomized, placebo and positive controlled study in 52 healthy individuals who are slow acetylators. At an exposure 2-fold the expected maximum therapeutic exposure of amifampridine, FIRDAPSE did not prolong QTc to any clinically relevant extent.
12.3Pharmacokinetics The pharmacokinetics of amifampridine are similar between healthy individuals and LEMS patients. Following single and multiple doses, AUC, C max and C min were highly variable between individuals. FIRDAPSE exposure increased proportionally with dose across the range of 20 mg to 80 mg single oral doses.
Absorption Amifampridine peak plasma concentration is reached 20 minutes to 1 hour after administration. Food does not have a clinically significant effect on the exposure of amifampridine. Elimination Amifampridine is eliminated primarily through metabolism to 3-N-acetyl-amifampridine and to a smaller extent through the kidneys.
The terminal half-life ranges from 1.8 to 2.5 hours in healthy subjects. Metabolism Amifampridine is extensively metabolized by N-acetyltransferase 2 (NAT2) to 3-N-acetyl-amifampridine, which is considered an inactive metabolite. Excretion Following administration of FIRDAPSE to healthy subjects, 93% to 100% of the administered dose was eliminated in the urine as amifampridine or 3-N-acetyl amifampridine over 24 hours.
Specific Populations Pediatric Patients (6 Years of Age and Older) A population pharmacokinetic analysis showed that body weight significantly correlates with the clearance of amifampridine; clearance increased with an increase in body weight. A weight-based dosing regimen is necessary to achieve amifampridine exposures in pediatric patients 6 years of age and older, similar to the exposures observed in adults at recommended doses of FIRDAPSE [see Dosage and Administration ( 2.1 ) and Clinical Studies ( 14 )]. Patients with Renal Impairment Pharmacokinetic data are available from a study of 24 otherwise healthy subjects with impaired renal function who received a single 10-mg dose of FIRDAPSE.
The exposure of amifampridine (measured as AUC) was 2- to 3-fold higher in subjects with moderate (CLcr 30-59 mL/min) or severe (CLcr 15-29 mL/min) renal impairment than in subjects with normal renal function (CLcr greater than or equal to 90 mL/min). Compared with subjects with normal renal function, subjects with mild renal impairment (CLcr 60-89 mL/min) had a 36% increase in exposure. Therefore, FIRDAPSE should be initiated at the lowest recommended initial daily dosage in patients with renal impairment, and such patients should be closely monitored for adverse reactions [see Dosage and Administration ( 2.2 ) and Use in Specific Populations ( 8.6 )] .
C max was marginally affected by renal impairment. Patients with Hepatic Impairment A study was conducted to determine the PK, safety, and tolerability of FIRDAPSE (amifampridine phosphate) administered at 10 mg to subjects with moderate hepatic impairment (N = 7) compared to demographically matched healthy subjects with normal hepatic function (N = 9). The subjects with moderate hepatic impairment had a 22% higher C max and a 33% higher AUC inf for amifampridine than subjects with normal hepatic function.
FIRDAPSE was not evaluated in subjects with severe hepatic impairment [see Dosage and Administration ( 2.3 ) and Use in Specific Populations ( 8.7 )] .
12.5Pharmacogenomics Genetic variants in the N-acetyltransferase gene 2 (NAT2) affect the rate and extent of FIRDAPSE metabolism. Poor metabolizers, also referred to as “slow acetylators” (i.e., carriers of two reduced function alleles), have 3.5- to 4.5-fold higher C max , and 5.6- to 9- fold higher AUC tha… [Excerpted — this section continues on DailyMed.]
🧬 Mechanism of Action ▾
12.1Mechanism of Action The mechanism by which amifampridine exerts its therapeutic effect in LEMS patients has not been fully elucidated. Amifampridine is a broad-spectrum potassium channel blocker.
📦 How Supplied / Storage and Handling ▾
16 HOW SUPPLIED/STORAGE AND HANDLING
16.1How Supplied FIRDAPSE 10 mg tablets are white to off white-round, and functionally scored. Each tablet is debossed on the non-scored side with “CATALYST” and on the scored side with “211” above the score and “10” below the score. Tablets can be divided in half at the score.
FIRDAPSE is supplied as follows: Child Resistant Blister Pack Blister pack containing 10 tablets NDC 69616-211-04 Carton containing 12 blister packs (120 tablets total) NDC 69616-211-06 Bottles 60 tablets NDC 69616-211-08 240 tablets NDC 69616-211-03
16.2Storage and Handling Store FIRDAPSE tablets at 20°C to 25°C (68°F to 77°F) with excursions permitted from 15°C to 30°C (59°F to 86°F) [see USP controlled room temperature]. See Dosage and Administration ( 2.5 ) for storage instructions for FIRDAPSE prepared suspension.
16.1How Supplied FIRDAPSE 10 mg tablets are white to off white-round, and functionally scored. Each tablet is debossed on the non-scored side with “CATALYST” and on the scored side with “211” above the score and “10” below the score. Tablets can be divided in half at the score.
FIRDAPSE is supplied as follows: Child Resistant Blister Pack Blister pack containing 10 tablets NDC 69616-211-04 Carton containing 12 blister packs (120 tablets total) NDC 69616-211-06 Bottles 60 tablets NDC 69616-211-08 240 tablets NDC 69616-211-03
📦 Storage and Handling ▾
16.2Storage and Handling Store FIRDAPSE tablets at 20°C to 25°C (68°F to 77°F) with excursions permitted from 15°C to 30°C (59°F to 86°F) [see USP controlled room temperature]. See Dosage and Administration ( 2.5 ) for storage instructions for FIRDAPSE prepared suspension.
📋 Description ▾
11 DESCRIPTION The active ingredient of FIRDAPSE is amifampridine phosphate, which is a voltage-gated potassium channel blocker. Amifampridine phosphate is described chemically as 3,4-diaminopyridine phosphate with a molecular weight of 207.1 and a molecular formula of C 5 H 7 N 3 • H 3 PO 4 . The structural formula is: Amifampridine phosphate is a white, crystalline powder that is freely soluble in water, and slightly soluble in solvents ethanol, methanol and acetic acid.
A 1% aqueous solution of amifampridine phosphate has a pH of 4.4 at ambient conditions. Each FIRDAPSE tablet contains 10 mg amifampridine (equivalent to 18.98 mg amifampridine phosphate). The tablet formulation includes the following inactive ingredients: calcium stearate, colloidal silicon dioxide, and microcrystalline cellulose.
FIRDAPSE tablets are intended for oral administration only. Structural Formula
💬 Information for Patients ▾
17 PATIENT COUNSELING INFORMATION Advise the patient and/or caregiver to read the FDA-approved patient labeling ( Medication Guide and Instructions for Use ). Risk of Seizures Inform patients that FIRDAPSE can cause seizures, and to notify their healthcare provider if they experience a seizure [see Warnings and Precautions ( 5.1 )] . Hypersensitivity Instruct patients to inform their healthcare provider if they have signs or symptoms of hypersensitivity, and to seek emergency help if symptoms of anaphylaxis occur [see Warnings and Precautions ( 5.2 )].
FIRDAPSE Dosing Instruct patients to take FIRDAPSE exactly as prescribed. Patients should carefully follow the dose escalation schedule provided by their healthcare provider to safely achieve the therapeutic dosage [see Dosage and Administration ( 2 )] . Inform patients that the tablets may be divided in half at the score, if needed.
Instruct patients not to take a double dose to make up for a missed dose. If they require a dosage in less than 5 mg increments, have difficulty swallowing tablets, or require feeding tubes, refer patients and/or caregivers to the Instructions for Use on how to prepare a 1 mg/mL suspension [ see Dosage and Administration ( 2.5 ) ]. If the patient requires treatment with the 1 mg/mL FIRDAPSE suspension, advise patients and/or caregivers that supplies required to prepare the suspension may be obtained at their local pharmacy.
Drug Interactions Instruct patients to notify their healthcare provider prior to starting any new medication, including over-the-counter drugs [see Drug Interactions ( 7 )]. Pregnancy Instruct patients that if they are pregnant or plan to become pregnant while taking FIRDAPSE they should inform their healthcare provider. Advise patients that there is a pregnancy registry that monitors pregnancy outcomes in women exposed to FIRDAPSE during pregnancy and encourage them to enroll if they become pregnant while taking FIRDAPSE [see Use in Specific Populations ( 8.1 )] .
Storage Advise patients to store FIRDAPSE at 68ºF to 77ºF (20ºC to 25ºC). Instruct patients and/or caregivers who prepare the 1 mg/mL suspension of FIRDAPSE that it should be prepared daily and refrigerated between doses. The suspension can be stored under refrigeration for up to 24 hours.
Instruct the patient and/or caregiver to discard any unused portion of the suspension after 24 hours. Distributed by Catalyst Pharmaceuticals, Inc., Coral Gables, FL 33134 FIRDAPSE is a trademark of SERB S.A. Catalyst and the Catalyst logo are trademarks of Catalyst Pharmaceuticals, Inc. © 2024 Catalyst Pharmaceuticals, Inc. – All rights reserved.
💬 Medication Guide ▾
This Medication Guide has been approved by the U.S. Food and Drug Administration Revised: 5/2024 MEDICATION GUIDE FIRDAPSE ® (FIR-dapse) (amifampridine) tablets, for oral use Read this Medication Guide before you start taking FIRDAPSE and each time you get a refill. There may be new information.
This information does not take the place of talking with your doctor about your medical condition or your treatment. What is the most important information I should know about FIRDAPSE? FIRDAPSE can cause seizures.
You could have a seizure even if you never had a seizure before. Do not take FIRDAPSE if you have ever had a seizure. Stop taking FIRDAPSE and call your doctor right away if you have a seizure while taking FIRDAPSE.
What is FIRDAPSE? FIRDAPSE is a prescription medicine used to treat Lambert-Eaton myasthenic syndrome (LEMS) in people 6 years of age and older. It is not known if FIRDAPSE is safe or effective in children less than 6 years of age.
Do not take FIRDAPSE if you: have ever had a seizure. are allergic to amifampridine phosphate, or another aminopyridine. Before you take FIRDAPSE, tell your doctor about all of your medical conditions. including if you: are taking another aminopyridine, such as compounded 3,4-diaminopyridine (3,4-DAP) have had a seizure have kidney problems have liver problems are pregnant or plan to become pregnant. It is not known if FIRDAPSE will harm your unborn baby.
You and your doctor will decide if you should take FIRDAPSE while you are pregnant. There is a registry for women who become pregnant during treatment with FIRDAPSE. The purpose of this registry is to collect information about your health and your baby's health.
Contact the registry as soon as you learn that you are pregnant, or ask your doctor to contact for you by calling 855-212-5856 (toll free), contacting the Fax number 877-867-1874 (toll free), emailing the Pregnancy Coordinating Center at [email protected], or visiting the study website www.firdapsepregnancystudy.com are breastfeeding or plan to breastfeed. It is not known if FIRDAPSE passes into your breast milk. Talk to your doctor about the best way to feed your baby while taking FIRDAPSE.
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? If your dose is less than 5mg, you have trouble swallowing tablets, or a feeding tube is needed, see the detailed Instructions for Use on how to take and prepare a suspension of FIRDAPSE.
Take FIRDAPSE exactly as your doctor tells you to take it. Do not change your dose of FIRDAPSE. Do not stop taking FIRDAPSE without first talking to your doctor.
FIRDAPSE tablets are scored and can be split if less than a full tablet is needed for you to get the right dose. FIRDAPSE can be taken with or without food. If you miss a dose of FIRDAPSE, skip that dose and take your next dose at your next scheduled dose time.
Do not double your dose to make up the missed dose. Do not take FIRDAPSE together with other medicines known to increase the risk of seizures. If you take too much FIRDAPSE, call your doctor or go to the nearest hospital emergency room right away.
What are the possible side effects of FIRDAPSE? FIRDAPSE may cause serious side effects, including: Seizures. See “ What is the most important information I should know about FIRDAPSE? ” Serious allergic reactions, such as anaphylaxis.
FIRDAPSE can cause serious allergic reactions. Stop taking FIRDAPSE and call your doctor right away or get emergency medical help if you have: shortness of breath or trouble breathing swelling of your throat or tongue hives The most common side effects of FIRDAPSE include: tingling around the mouth, tongue, face, fingers, toes, and other body parts upper respiratory infection stomach pain nausea diarrhea headache increased liver enzymes back pain high blood pressure muscle spasms Tell your doctor if you have any side effect that bothe… [Excerpted — this section continues on DailyMed.]
🧬 Pharmacokinetics ▾
12.3Pharmacokinetics The pharmacokinetics of amifampridine are similar between healthy individuals and LEMS patients. Following single and multiple doses, AUC, C max and C min were highly variable between individuals. FIRDAPSE exposure increased proportionally with dose across the range of 20 mg to 80 mg single oral doses.
Absorption Amifampridine peak plasma concentration is reached 20 minutes to 1 hour after administration. Food does not have a clinically significant effect on the exposure of amifampridine. Elimination Amifampridine is eliminated primarily through metabolism to 3-N-acetyl-amifampridine and to a smaller extent through the kidneys.
The terminal half-life ranges from 1.8 to 2.5 hours in healthy subjects. Metabolism Amifampridine is extensively metabolized by N-acetyltransferase 2 (NAT2) to 3-N-acetyl-amifampridine, which is considered an inactive metabolite. Excretion Following administration of FIRDAPSE to healthy subjects, 93% to 100% of the administered dose was eliminated in the urine as amifampridine or 3-N-acetyl amifampridine over 24 hours.
Specific Populations Pediatric Patients (6 Years of Age and Older) A population pharmacokinetic analysis showed that body weight significantly correlates with the clearance of amifampridine; clearance increased with an increase in body weight. A weight-based dosing regimen is necessary to achieve amifampridine exposures in pediatric patients 6 years of age and older, similar to the exposures observed in adults at recommended doses of FIRDAPSE [see Dosage and Administration ( 2.1 ) and Clinical Studies ( 14 )]. Patients with Renal Impairment Pharmacokinetic data are available from a study of 24 otherwise healthy subjects with impaired renal function who received a single 10-mg dose of FIRDAPSE.
The exposure of amifampridine (measured as AUC) was 2- to 3-fold higher in subjects with moderate (CLcr 30-59 mL/min) or severe (CLcr 15-29 mL/min) renal impairment than in subjects with normal renal function (CLcr greater than or equal to 90 mL/min). Compared with subjects with normal renal function, subjects with mild renal impairment (CLcr 60-89 mL/min) had a 36% increase in exposure. Therefore, FIRDAPSE should be initiated at the lowest recommended initial daily dosage in patients with renal impairment, and such patients should be closely monitored for adverse reactions [see Dosage and Administration ( 2.2 ) and Use in Specific Populations ( 8.6 )] .
C max was marginally affected by renal impairment. Patients with Hepatic Impairment A study was conducted to determine the PK, safety, and tolerability of FIRDAPSE (amifampridine phosphate) administered at 10 mg to subjects with moderate hepatic impairment (N = 7) compared to demographically matched healthy subjects with normal hepatic function (N = 9). The subjects with moderate hepatic impairment had a 22% higher C max and a 33% higher AUC inf for amifampridine than subjects with normal hepatic function.
FIRDAPSE was not evaluated in subjects with severe hepatic impairment [see Dosage and Administration ( 2.3 ) and Use in Specific Populations ( 8.7 )] .
🧬 Pharmacodynamics ▾
12.2Pharmacodynamics The effect of FIRDAPSE on QTc interval prolongation was studied in a double blind, randomized, placebo and positive controlled study in 52 healthy individuals who are slow acetylators. At an exposure 2-fold the expected maximum therapeutic exposure of amifampridine, FIRDAPSE did not prolong QTc to any clinically relevant extent.
🔬 Clinical Studies ▾
14 CLINICAL STUDIES The efficacy of FIRDAPSE for the treatment of LEMS was demonstrated in two randomized, double-blind, placebo-controlled discontinuation studies. A total of 64 adults (age 21 to 88 years) with LEMS were enrolled (Study 1 and Study 2). The studies enrolled patients with a confirmed diagnosis of LEMS based on either neurophysiology studies or a positive anti-P/Q type voltage-gated calcium channel antibody test.
Patients were required to be on an adequate and stable dosage (30 to 80 mg daily) of amifampridine phosphate prior to entering the randomized discontinuation phases of both studies. The two co-primary measures of efficacy in both studies were the change from baseline to the end of the discontinuation period in the Quantitative Myasthenia Gravis (QMG) score and in the Subject Global Impression (SGI) score. The QMG is a 13-item physician-rated categorical scale assessing muscle weakness.
Each item is assessed on a 4-point scale, where a score of 0 represents no weakness, and a score of 3 represents severe weakness (total score 0-39). Higher scores represent greater impairment. The SGI is a 7-point scale on which patients rated their global impression of the effects of the study treatment on their physical well- being.
Lower scores on the SGI represent lower perceived benefit with the study treatment. A key secondary efficacy endpoint was the clinical global impression improvement (CGI-I) score, a 7-point scale on which the treating physician rated the global impression of change in clinical symptoms. A higher CGI-I score indicates a perceived worsening of clinical symptoms.
Study 1 (NCT01377922) After an initial open-label run-in phase, 38 patients were randomized in a double-blind fashion to either continue treatment with FIRDAPSE (n=16) or to a downward titration to placebo (n=22) over 7 days. Following the downward titration period, patients remained on blinded FIRDAPSE or placebo for 7 more days. Efficacy was assessed at Day 14 of the double-blind period.
Patients were allowed to use stable dosages of peripherally acting cholinesterase inhibitors or oral immunosuppressants. Twenty-six percent of patients randomized to FIRDAPSE were receiving cholinesterase inhibitors, versus 36% in the placebo group, and 28% of patients randomized to FIRDAPSE were receiving oral immunosuppressant therapies, versus 34% in the placebo group. Patients had a median age of 54 years (range: 21 to 88 years), 61% were female, and 90% were White.
Eighty-four percent of patients had a diagnosis of autoimmune LEMS, and 16% of patients had a diagnosis of paraneoplastic LEMS. During the double-blind period (from Baseline to Day 14), the QMG scores tended to worsen in both treatment groups, but there was significantly greater worsening in the placebo group than in the FIRDAPSE group ( p =0.045). Similarly, the SGI score tended to worsen in both treatment groups during the double-blind period, but there was significantly greater worsening in the placebo group than in the FIRDAPSE group ( p =0.003), as summarized in Table 3 .
These results indicate that in Study 1, patients randomized to placebo had a significantly greater worsening of muscle weakness and of global impression of the effects of the study treatment on their physical well-being, compared to patients who continued FIRDAPSE in the double-blind period. Table 3. Change from Baseline to Day 14 in QMG Score and SGI Score in Study 1 a.
QMG Score range 0 (no impairment) to 39 (worst impairment) b. SGI Score range 0 (least perceived benefit) to 7 (most perceived benefit) c. Pairwise contrast at Day 14 from mixed-effects model with repeated measures.
Assessment FIRDAPSE (n=16) Placebo (n=21) Primary Endpoints QMG Score a Baseline (mean) 6.4
5.6Change from Baseline (Least Square Mean) 0.4
2.2FIRDAPSE-placebo Treatment Difference (Least Square Mean (95% CI)) –1.7 (–3.4, –0.0) p -value c 0.045 SGI Score b Baseline (mean) 5.6
5.9Change from Baseline (Least Square Mean) -0.8 -2.6 F… [Excerpted — this section continues on DailyMed.]
🧪 Nonclinical Toxicology ▾
13 NONCLINICAL TOXICOLOGY
13.1Carcinogenesis, Mutagenesis, Impairment of Fertility Carcinogenicity In a 104-week carcinogenicity study in rats, oral administration of amifampridine phosphate (0, 15, 48, or 105 mg/kg/day) resulted in an increase in uterine tumors (endometrial carcinoma and combined endometrial adenoma/endometrial carcinoma/squamous cell carcinoma) at the mid and high doses tested. The low dose, not associated with an increase in tumors, is less than the maximum recommended human dose (MRHD) of amifampridine (100 mg/day) on a body surface area (mg/m 2 basis).
In a 26-week carcinogenicity study in transgenic (Tg.rasH2) mice, oral administration of amifampridine phosphate (0, 2, 7, or 21 mg/kg/day in males and 0, 3, 10, or 30 mg/kg/day in females) resulted in no increase in tumors. Mutagenesis Amifampridine phosphate was negative in the in vitro bacterial reverse mutation and in vivo rat micronucleus assays. Amifampridine phosphate was positive for clastogenicity in the in vitro mouse lymphoma tk assay in the absence of metabolic activation.
Impairment of Fertility Oral administration of amifampridine phosphate (0, 7.5, 22.5, or 75 mg/kg/day) to male and female rats prior to and during mating, and continuing in females throughout organogenesis, produced no adverse effects on fertility. The highest dose tested is approximately 4 times the MRHD of amifampridine on a body surface area (mg/m 2 ) basis.
📄 Carcinogenesis, Mutagenesis, Impairment of Fertility ▾
13.1Carcinogenesis, Mutagenesis, Impairment of Fertility Carcinogenicity In a 104-week carcinogenicity study in rats, oral administration of amifampridine phosphate (0, 15, 48, or 105 mg/kg/day) resulted in an increase in uterine tumors (endometrial carcinoma and combined endometrial adenoma/endometrial carcinoma/squamous cell carcinoma) at the mid and high doses tested. The low dose, not associated with an increase in tumors, is less than the maximum recommended human dose (MRHD) of amifampridine (100 mg/day) on a body surface area (mg/m 2 basis).
In a 26-week carcinogenicity study in transgenic (Tg.rasH2) mice, oral administration of amifampridine phosphate (0, 2, 7, or 21 mg/kg/day in males and 0, 3, 10, or 30 mg/kg/day in females) resulted in no increase in tumors. Mutagenesis Amifampridine phosphate was negative in the in vitro bacterial reverse mutation and in vivo rat micronucleus assays. Amifampridine phosphate was positive for clastogenicity in the in vitro mouse lymphoma tk assay in the absence of metabolic activation.
Impairment of Fertility Oral administration of amifampridine phosphate (0, 7.5, 22.5, or 75 mg/kg/day) to male and female rats prior to and during mating, and continuing in females throughout organogenesis, produced no adverse effects on fertility. The highest dose tested is approximately 4 times the MRHD of amifampridine on a body surface area (mg/m 2 ) basis.
📖 Instructions for Use ▾
Instructions for Use FIRDAPSE (FIR-dapse) (amifampridine) tablets for oral use This Instructions for Use contains information on how to mix and use FIRDAPSE prepared suspension. The FIRDAPSE prepared suspension can be used for people who are prescribed a dosage that cannot be obtained with whole or half tablets, who have trouble swallowing tablets, or who have a feeding tube. Prepare FIRDAPSE oral suspension each day.
Supplies you will need: You can get these supplies at your local pharmacy. your FIRDAPSE tablets empty bottle with cap (50-100 mL recommended) sterile water oral syringe with catheter tip (10mL, may require smaller syringe for dosing) Instructions to make a 1 mg/mL suspension: Important: Do not use any foods or liquids other than sterile water to mix FIRDAPSE. You can prepare each dose separately or all of your doses for the day at one time. Step 1 Step 2 Step 3 Place the number of FIRDAPSE tablets you need for your dose or doses in a bottle.
For each tablet, add 10 mL of water to the bottle. Measure the water with an oral syringe, and inject the water into the bottle. Note: Depending on the number of tablets and the size of the syringe, you may need to measure and inject the water more than one time.
Secure the cap back on the bottle. Wait for 5 minutes. Shake well for 30 seconds.
Instructions to administer the prepared suspension: Important: Prepare fresh suspensions daily. If you prepare all of your doses for the day at one time, refrigerate the suspension between doses. Shake well before drawing up each dose.
OPTION 1 To administer by mouth : Step 4 Step 5 Remove the bottle cap and use an oral syringe with a catheter tip to measure the prescribed dose. Push syringe plunger to administer by mouth. Note: Depending on the dose and size of syringe, you may need to repeat steps 4 and 5 until the prescribed dose is given.
OPTION 2 To administer by feeding tube : Important: Do not use any foods or liquids other than sterile water to mix FIRDAPSE. Use only an oral syringe with a catheter tip to give FIRDAPSE through the feeding tube. Talk to your healthcare provider about the size catheter tipped syringe you should use.
Step 4 Step 5 Remove the bottle cap and use an oral syringe with a catheter tip to measure the prescribed dose. Inject the medicine using the oral syringe with a catheter tip into the feeding tube right away. Note: Depending on the dose and size of syringe, you may need to repeat steps 4 and 5 until the prescribed dose is given.
Step 6 Step 7 To flush the feeding tube: Refill the syringe with 10 mL of sterile water. Shake the syringe, insert the catheter tip into the feeding tube to flush any remaining medicine from the feeding tube into the stomach. How should I store FIRDAPSE?
Firdapse tablets: Store FIRDAPSE tablets at room temperature between 68ºF to 77ºF (20ºC to 25ºC). Safely throw away FIRDAPSE tablets that are out of date or no longer needed. Firdapse prepared suspension: Store FIRDAPSE prepared oral suspension in the refrigerator between 36°F to 46°F (2°C to 8°C) between doses for up to 24 hours.
Safely throw away unused FIRDAPSE oral suspension after 24 hours. Distributed by Catalyst Pharmaceuticals, Inc., Coral Gables, FL 33134 For more information, go to www.YourCatalystPathways.com or call 1-833-422-8259 This Instructions for Use has been approved by the U.S. Food and Drug Administration.
Approved: 5/2024 Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure
📄 Recent Major Changes ▾
Dosage and Administration ( 2.1 ) 5/2024
📄 Package Label / Principal Display Panel ▾
PRINCIPAL DISPLAY PANEL - 10 mg Tablet Blister Pack Carton Rx Only NDC 69616-211-06 120 Tablets Total Provided in 12 Child-Resistant Blister Cards Of 10 Tablets Each FIRDAPSE ® (amifampridine) Tablets 10 mg per Tablet Manufactured for: Catalyst Pharmaceuticals, Inc. Coral Gables, FL 33134 image description
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