Dalfampridine

2 DOSAGE AND ADMINISTRATION The maximum recommended dosage is 10 mg twice daily (approximately 12 hours apart). There is no evidence of additional benefit with doses greater than 10 mg twice daily. Adverse reactions, including seizures, were more frequent at higher doses.

1) Take with or without food. 2) Patients should not take double or extra doses if they miss a dose. 2) Estimated creatinine clearance (CrCl) should be known before initiating treatment with dalfampridine extended-release tablets. 1 Dosage Information The maximum recommended dosage of dalfampridine extended-release tablet is one 10 mg tablet twice daily and should not be exceeded.

Take doses approximately 12 hours apart. There is no evidence of additional benefit at doses greater than 10 mg twice daily. Adverse reactions, including seizures, and discontinuations because of adverse reactions were more frequent at higher doses.

2 Administration Instructions Dalfampridine extended-release tablet can be taken with or without food. Administer tablets whole; do not divide, crush, chew, or dissolve dalfampridine extended-release tablets. If a dose is missed, patients should not take double or extra doses.

3 Renal Monitoring Prior to and During Treatment Estimated creatinine clearance (CrCl) should be known before initiating treatment with dalfampridine extended-release tablets, and monitored at least annually during treatment with dalfampridine extended-release tablets.

5 times the maximum recommended dose and may be associated with an increased risk of seizures. As mild renal impairment is common after age 50, estimating CrCl is particularly important in these patients. 3)]. Dalfampridine extended-release tablet is contraindicated in patients with moderate or severe renal impairment (CrCl≤50 mL/min).

1). gov/medwatch. 1 Clinical Trials Experience Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice.

In three placebo-controlled clinical trials of up to 14 weeks duration, 4% (15/400) of patients treated with dalfampridine extended-release tablets 10 mg twice daily experienced one or more adverse reactions leading to discontinuation, compared to 2% (5/238) of placebo-treated patients.

3%, placebo 0%). Table 1 lists adverse reactions that occurred in ≥2% of patients treated with dalfampridine extended-release tablets 10 mg twice daily, and more frequently than in placebo-treated patients, in controlled clinical trials.

Table 1:

Adverse Reactions with an Incidence ≥2% of dalfampridine extended-release tablets-Treated Adult MS Patients and More Frequent with dalfampridine extended-release tablets Compared to Placebo in Controlled Clinical Trials Adverse Reaction Placebo (N=238) % Dalfampridine extended-release tablets 10 mg twice daily (N=400) % Urinary tract infection 8 12 Insomnia 4 9 Dizziness 4 7 Headache 4 7 Nausea 3 7 Asthenia 4 7 Back pain 2 5 Balance disorder 1 5 Multiple sclerosis relapse 3 4 Paresthesia 3 4 Nasopharyngitis 2 4 Constipation 2 3 Dyspepsia 1 2 Pharyngolaryngeal pain 1 2 Other Adverse Reactions Dalfampridine extended-release tablets has been evaluated in a total of 1,952 subjects, including 917 MS patients.

A total of 741 patients have been treated with dalfampridine extended-release tablets for over six months, 501 for over one year and 352 for over two years. The experience in open-label clinical trials is consistent with the safety profile observed in the placebo-controlled clinical trials.

3 ) Dalfampridine extended-release tablets can cause anaphylaxis. 1 Seizures Dalfampridine extended-release tablets can cause seizures. Increased incidence of seizures has been observed at 20 mg twice daily (2 times the maximum recommended dosage) in controlled clinical studies of 9 to 14 weeks duration with dalfampridine in patients with MS.

4/100PY). In the post-marketing period seizures have been reported. The majority of seizures occurred at the recommended dose and in patients without a history of seizures, and generally within days to weeks of starting therapy. Dalfampridine extended-release tablets has not been evaluated in patients with a history of seizures or with evidence of epileptiform activity on an EEG, as these patients were excluded from clinical trials.

The risk of seizures in patients with epileptiform activity on an EEG is unknown, and could be substantially higher than that observed in dalfampridine extended-release tablets clinical studies. Permanently discontinue dalfampridine extended-release tablets in patients who have a seizure while on treatment.

Dalfampridine extended-release tablets are contraindicated in patients with a history of seizures [see Contraindications (4)] . 3)]. Because patients with moderate to severe renal impairment (CrCl ≤50mL/min) would require a dose lower than 10 mg twice daily and no strength smaller than 10 mg is available, dalfampridine extended-release tablets are contraindicated in these patients [see Contraindications (4)].

1)]. 3 Concurrent Treatment with Other Forms of 4-Aminopyridine Avoid concomitant use with other forms of 4-aminopyridine (4-AP, fampridine) since the active ingredient is the same. Instruct patients to discontinue use of any product containing 4-aminopyridine prior to initiating treatment with dalfampridine extended-release tablets in order to reduce the potential for dose-related adverse reactions.

4)] History of seizure (4) Moderate or severe renal impairment (CrCl≤50 mL/min) (4) History of hypersensitivity to dalfampridine extended-release tablets or 4-aminopyridine (4)