ClinicalTrials.gg
Approved for marketingNCT02189720EAP-001Updated Mar 26, 2025

Expanded Access Study Amifampridine Phosphate in Lambert-Eaton Myasthenic Syndrome (LEMS),Congenital Myasthenic Syndrome

An expanded access record providing Amifampridine Phosphate in Congenital Myasthenic Syndrome, Lambert-Eaton Myasthenic Syndrome and Nystagmus, Acquired, sponsored by Catalyst Pharmaceuticals, Inc.. Approved for marketing at 1 site in United States. Open to participants aged 2 Years and older. Per ClinicalTrials.gov, last updated 2025-03-26.

Sponsored by Catalyst Pharmaceuticals, Inc. (part of Angelini Pharma) · Expanded access

Study type
Expanded access
Ages
2 Years and older
Sex
All
01

Study summary

Primary:

The primary objective of this study under the original protocol was to provide neuromuscular specialists and neurologists access to amifampridine phosphate therapy for their patients with LEMS, CMS or downbeat nystagmus until the product became commercially available.

Secondary:

The secondary objective of this study under the original protocol was to provide additional long-term safety data on amifampridine phosphate in patients.

Primary The primary objective of this study after its fifth amendment was to provide access to amifampridine phosphate therapy to pediatric patients with LEMS, and pediatric and adult patients with CMS until the product became commercially available for these indications or development of the product for the indication was terminated.

Secondary:

The secondary objective of this study after its fifth amendment was to assess the long-term safety of amifampridine phosphate in pediatric patients with LEMS, and pediatric and adult patients with CMS.

Read the detailed description

This multicenter, expanded access study was designed to allow EAP-001 Investigators, neuromuscular specialists, and neurologists access to amifampridine phosphate therapy for their patients with LEMS, CMS, or downbeat nystagmus until such time the product became commercially available for these specific indications or development of the product for the indication was terminated. Given that these are chronic conditions, this study obtained some long-term safety data by evaluating Adverse Events, physical exams, vital signs, standard safety laboratory tests (chemistry, hematology, and urinalysis), pregnancy testing (if applicable) and abnormal ECG findings, where each of these data/measures were performed as part of a routine standard of care treatment provided by the Principal Investigator or the patient's personal physician(s) (i.e., could be performed by a different physician not involved in the treatment of neuromuscular disease).

Planned -100 sites in US and up to 200 patients. Actual- 50 sites activated and 200 patients enrolled.

Patients were seen at screening/baseline, Day 1 and at least once per year at the PIs discretion. With the COVID-19 Pandemic, telehealth visits were allowed and assessments that could be completed via remote telehealth visits were performed via phone or videoconference. Follow-up visits included Physical exams, vital signs, standard safety laboratory tests (chemistry, hematology, and urinalysis), pregnancy testing (if applicable) and ECGs.

Patients were titrated to an optimal individualized dose of amifampridine phosphate based on Principal Investigator assessment of optimal neuromuscular benefit. In patients already taking amifampridine base, amifampridine phosphate was started at an equivalent or lower dose of amifampridine phosphate, at the Principal Investigator's discretion. Therapeutic doses were to range from 10 to 80 mg, divided into doses taken two (2) to four (4) times per day, with a maximum single dose of 20 mg. For upward titration, amifampridine phosphate could be increased by 10 mg increments every four (4) to five (5) days to a maximum of 80 mg per day (ages >16 years), and to a maximum of 60 mg (ages 2 to 16 years) based on optimal neuromuscular benefit and at the discretion of the Principal Investigator. If needed, titration could occur in 5 mg/dose and per day increments. Drug was shipped to the clinic for the first dose ( Day 1) and subsequent shipments were sent to the patients home by a specialty pharmacy.

In addition to amifampridine phosphate, patients received best supportive care (BSC) treatment as determined by the Principal Investigator using concomitant medications permitted by protocol, including selected oral immunosuppressant's (i.e., prednisone or other corticosteroids, azathioprine, mycophenolate) and peripherally acting cholinesterase inhibitors (e.g., pyridostigmine). Changes to BSC could be made at the Principal Investigator's discretion, as long as prohibited concomitant medications were not used.

Firdapse® was approved for adult patients with LEMS in November 2018 and approved for pediatric patients with LEMS ages 6 years and older in September 2022. The indications for CMS and DBN were not pursued.

02

Conditions studied

  • Congenital Myasthenic Syndrome
  • Lambert-Eaton Myasthenic Syndrome
  • Nystagmus, Acquired

Keywords

  • Amifampridine Phosphate
  • Amifampridine
  • 3,4-Diaminopyridine Phosphate
  • 3,4-Diaminopyridine
  • 3,4-DAP
  • CMS
  • Congenital Myasthenic Syndrome
  • Neuromuscular
  • Expanded Access
  • Firdapse®
  • LEMS
03

In context

Lambert-Eaton Myasthenic Syndrome

22 studies on the registry are indexed under Lambert-Eaton Myasthenic Syndrome; 5 are open to participants now.

Browse Lambert-Eaton Myasthenic Syndrome studies →

Lead sponsor

Catalyst Pharmaceuticals, Inc. is the lead sponsor of 13 studies on the registry; 1 is open to participants now.

First submitted before Catalyst Pharmaceuticals, Inc. became part of Angelini Pharma.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
2 Years and older
Sexes eligible
All

Eligibility criteria

Inclusion Criteria - Amendment 5 v6 - most recent version

  • Male or female:

    • 2 years of age
  • Confirmed physician diagnosis of LEMS in pediatric patients or CMS in either pediatric or adult patients.
  • Completion of anti-cancer treatment at least 3 months (90 days) before treatment.
  • Negative urine pregnancy test for females of at Screening.
  • If sexually active and of childbearing potential, willing to use 2 acceptable methods of from screening visit until 3 months after the last dose of product. No adequate clinical data on exposed pregnancies are available for amifampridine. No nonclinical safety data are available regarding the effects of amifampridine on reproductive function. Amifampridine phosphate should not be used during pregnancy. It is unknown whether amifampridine is excreted in human breast milk. The excretion of amifampridine in milk has not been studied in animals. Amifampridine phosphate should not be used during breastfeeding.
  • Any subject currently participating in study CMS 001 is immediately eligible for enrollment into study EAP-001, as long as inclusion/exclusion criteria are still met.
  • Willing and able to provide written after the nature of the study has been explained and before the start of any research-related procedures.

Exclusion Criteria- Amendment 5 v6

  • History of epilepsy and on medication/treatment for the same.
  • CMS subtypes including slow-channel syndrome, LRP4 deficiency, plectin deficiency and acetylcholinesterase deficiency.
  • Any subject with a LEMS diagnosis and ≥18 years of age.
  • Known active . Patients with treated brain metastasis (radiotherapy and/or surgery) who have completed treatment for their brain metastasis >90 days before Screening, are neurologically stable (neurological symptoms grade \<1), are on a stable dose of and have no evidence of new disease on magnetic resonance imaging (MRI) are eligible, provided they meet the other inclusion/exclusion criteria.
  • Current use of dalfampridine (Ampyra®; 4-aminopyridine), and any form of 3,4 DAP other than the investigational product provided, such as amifampridine base and does not agree to discontinue use for the duration of the study.
  • Use of guanidine hydrochloride within 7 days of starting amifampridine phosphate treatment.
  • History of drug allergy to any pyridine-containing substances or any amifampridine phosphate (i.e. microcrystalline cellulose, colloidal silicon dioxide or calcium stearate).
  • Use of any other investigational product (other than 3,4 DAP or amifampridine phosphate) or investigational medical device within 30 days before starting treatment or requirement for any investigational agent before completion of all scheduled study assessments.
  • An (ECG) within 6 months before starting treatment that shows abnormality(ies), in the opinion of the patient's personal physician for pediatric subjects \<18 years of age.
  • Breastfeeding or pregnant or planning to become pregnant (self or partner). Male patients with breastfeeding partners are not excluded from the study.
  • Patients with end stage kidney disease on dialysis.
  • Any condition that, in the view of the Principal Investigator, places the patient at risk, or patients with poor treatment compliance.

Inclusion Criteria: Protocol Amendment 1 ( first version IRB approved)

  • Male or female:
  • Confirmed genetic diagnosis of CMS.
  • Negative urine pregnancy test for females of childbearing potential at Screening.
  • If sexually active and of childbearing potential, willing to use 2 acceptable methods of contraception from screening visit until 3 months after the last dose of investigational product. No adequate clinical data on exposed pregnancies are available for amifampridine. No nonclinical safety data are available regarding the effects of amifampridine on reproductive function. Amifampridine phosphate should not be used during pregnancy. It is unknown whether amifampridine is excreted in human breast milk. The excretion of amifampridine in milk has not been studied in animals. Amifampridine phosphate should not be used during breastfeeding.
  • Willing and able to provide written informed consent after the nature of the study has been explained and before the start of any research-related procedures.

Exclusion Criteria: Protocol Amendment 1 ( first version IRB approved)

  • History of epilepsy and on medication/treatment for the same.
  • CMS subtypes including slow-channel syndrome, LRP4 deficiency, and acetylcholinesterase deficiency.
  • Current use of dalfampridine (Ampyra®; 4-aminopyridine), and any form of 3,4 DAP other than the investigational product provided, such as amifampridine base and does not agree to discontinue use for the duration of the study.
  • Use of guanidine hydrochloride within 7 days of starting amifampridine phosphate treatment.
  • History of drug allergy to any pyridine-containing substances or any amifampridine phosphate excipients (i.e. microcrystalline cellulose, colloidal silicon dioxide or calcium stearate).
  • Use of any other investigational product (other than 3,4 DAP or amifampridine phosphate) or investigational medical device within 30 days before starting treatment or requirement for any investigational agent before completion of all scheduled study assessments.
  • An electrocardiogram (ECG) within 6 months before starting treatment that shows clinically significant abnormality(ies), in the opinion of the patient's personal physician.
  • Breastfeeding or pregnant or planning to become pregnant (self or partner). Male patients with breastfeeding partners are not excluded from the study.
  • Any condition that, in the view of the Principal Investigator, places the patient at high risk of poor treatment compliance or of not completing the study.
Terms in these criteria, in plain language(9)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Brain metastases

Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).

Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Excipients

The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.

ECG (electrocardiogram)

A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

05

Access details

Study type
Expanded access

Available treatment

  • Dosage form: tablets containing the equivalent of 10 mg amifampridine per tablet. Amifampridine Phosphate given based on Investigator assessment of optimal neuromuscular benefit. In adult patients \> 16 years of age, Doses ranged from 30 mg to 80 mg, divided into doses taken 3 to 4 times per day and in pediatric patients age \< 16 years the maximum daily dose was 60 mg/day. No single dose to exceed 20 mg.

    Also known as: 3,4-Diaminopyridine Phosphate, 3,4 DAP, Firdapse®

06

Where to request access

1 site
  • UCLA
    Los Angeles, California 90095, United States
07

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Mar 26, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
08

Registry details

Key details

Study ID
NCT02189720
Responsible party
Sponsor
First posted
Jul 15, 2014
Last update
Mar 26, 2025

Study contacts

Perry Shieh, MD, PhD
principal investigator · University of California, Los Angeles
View the source record on ClinicalTrials.gov ↗

Requesting access

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No contact was published for this record. The registry link below has the sponsor’s details.

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