Abbreviations or special terms	Explanation of the invention
		SEM	Mean standard error
SPF	Free of specific pathogens
		SR	Sustained release
SS	Steady state
		t_1/2	Apparent terminal elimination half-life
t.i.d.(tid)	Three times daily
		TK	Pharmacokinetics of toxicity
TLC	Thin layer chromatography
		T_max	Time of maximum plasma concentration measurement
USP	United states pharmacopoeia
		UTI	Urinary tract infection
V_d	Volume of distribution
		V_dss	StableVolume of distribution of state

It should be noted that aminopyridine-SR, when used herein, should be considered only as an example of a sustained release 4-AP composition. Other sustained release compositions are also within the scope of the present invention. Furthermore, while BID or other uses of sustained release 4AP are disclosed, which is only an example, modified dosing regimens (without limitations like QD or TID) are also within the scope of the invention. Thus, modified release formulations (in addition to sustained release) and modified dosing cycles (in addition to BID) are also within the scope of the invention.

In the claims, the words "a" or "an" when used in conjunction with the word "comprising" or other open language means "one or more"

Although the present invention has been described herein in considerable detail with respect to certain preferred embodiments thereof, other versions are possible. The spirit and scope of the appended claims should not be limited to the description and the preferred versions contained within this specification. All documents mentioned herein are incorporated herein by reference in their entirety for all purposes.

Brief description of the drawings

The following drawings form part of the present specification and are included to demonstrate certain aspects of the present disclosure in greater detail. The invention may be better understood by reference to any one of these drawings in combination with the detailed description of specific embodiments contained herein.

FIG. 1 shows information about 4-aminopyridine.

FIG. 2: primary endpoint for MS-F203: aminopyridine-SR improves timing walking.

FIG. 3: and (4) configuring the patient.

FIG. 4: a baseline demographic.

FIG. 5: MS-F203 overall patient survival.

FIG. 6: MS-F203 overall patient survival.

FIG. 7: extended timing walking

FIG. 8: walking speed variation of extended timing walking answering group

FIG. 9: persistence of extended responder groups

FIG. 10: overall score for extended response groups

FIG. 11: relationship between timing walking responses in double-blind and extended studies

FIG. 12: MS F203 EXT: adverse events

FIG. 13: MS-F203 EXT: the most common adverse event (TEAE) that occurs after treatment.

FIG. 14: severe adverse events following treatment occurred in > 1 individuals

FIG. 15: 4-aminopyridine in plasma after administration of 10mg IR aminopyridine.

FIG. 16: steady state pharmacokinetic profile of sustained release 4-aminopyridines

Detailed description of the invention

The chemical 4-aminopyridine is a potassium (K +) channel blocker approved or evaluated as a therapeutic agent, for example for improving nerve and muscle function in patients with Multiple Sclerosis (MS); aminopyridine is the name of this compound elsewhere in the world. Dafanopyridine is the American common name (USAN) for 4-aminopyridine (4AP) and has the molecular formula C₅H₆N₂The molecular weight is 94.1. Within this specification, "aminopyridine", "daparinux" and "4-aminopyridine" will be used to refer to the active agent. 4-aminopyridinesHave been formulated as Sustained Release (SR) matrix tablets with various concentrations ranging from 5 to 40 mg. aminopyridine-SR is available in the United states, for example under the trademark AmpyraAcordia Therapeutics, Hawthorne, NY in the form of tablets with a concentration of 10 mg. In one embodiment, the following excipients are generally included in each tablet: hydroxypropyl methylcellulose, USP; microcrystalline cellulose, USP; colloidal silica, NF; magnesium stearate, USP; and opadry.

Effect on axonal conductionPharmacologically, the K + channel blocking properties of 4-aminopyridine and its effect on action potential conduction in demyelinated nerve fiber preparations have been widely characterized. At low concentrations associated with clinical experience, 4-aminopyridine was able to block certain voltage-dependent K + channels in neurons in the 0.2-2 μ M (18-180ng/mL) range. This feature appears to explain the ability of drugs to restore action potential conduction in demyelinated nerve fibers. At high concentrations (millimolar), 4-aminopyridine affects other types of K + channels in both neural and non-neural tissue. Blockade of repolarized K + flow can increase synaptic transmission within the nervous system by increasing the time course of the presynaptic action potential. A range of neurological effects are consistent with the increase in pre-synaptic nerve terminal excitability caused by clinically relevant doses of 4-aminopyridine.

K + channels blocked by low concentrations of 4-aminopyridine have in part an effect on repolarization of neuronal action potentials. This appears to include those channels found under the myelin sheath of adult mammalian myelinated nerve fibers. These channels are located mainly on the paraganglionic and internodal membranes of axons (Waxman and ritchae, 1993) because myelin sheaths act as an electrical barrier, so they are not significantly activated by the passage of action potentials. Thus, the action potential of normal adult myelinated axons shows very low sensitivity or complete insensitivity to 4-aminopyridine at concentrations below 100. mu.M (9.4. mu.g/mL) (Shi and Blight, 1997). Concentrations above 1mM (94.1. mu.g/mL) tend to cause progressive depolarization of axon resting potential, perhaps through interaction with leaky channels (Shi and Blight, 1997).

However, after demyelination of the axon, the internode membrane and its ion channels begin to be exposed to larger electrical transients during the action potential. Under these conditions, ion current leakage through the K + channel can contribute to the phenomenon of blocking of action potential conduction (Waxman and ritchai, 1993). Without being bound by theory, it is understood that 4-aminopyridines can prolong nerve action potentials by blocking these exposed channels and inhibiting repolarization (Sherrat et al, 1980). This is consistent with the ability of drugs to overcome conduction blockages and increase the safety factor for conduction in some severely demyelinated axons (Bostock et al, 1981; Targ and Kocsis, 1985), including axons in chronically injured and partially demyelinated mammalian spinal cords (Bright, 1989; Shi and Blight, 1997). Additional studies (Shi et al, 1997) showed that this effect of 4-aminopyridine in chronically injured spinal cords in guinea pigs occurred between concentration thresholds of 0.2 to 1. mu.M (19.1 to 94.1ng/mL), although it was most effective at about 10. mu.M (941ng/mL) in this tissue.

It is understood that blockade of K + flow amplifies synaptic transmission in the brain and spinal cord.

In the Central Nervous System (CNS), with increasing concentrations of 4-aminopyridine, a range of neurological effects occur, even and including the initiation of epilepsy. After a large dose of 4-aminopyridine, seizures are visible in the animals and are part of the toxicological profile of the drug. A synchronized burst activity was recorded in the spinal cord of a cerebrated cat following administration of a very large dose of 4-aminopyridine (5 to 20mg/kg), which is expected to produce plasma levels in the range of several hundred ng/mL (Dubuc et al, 1986).

Repetitive pulsatile activity, whether spontaneous or in response to a single stimulus, occurs in vitro in demyelinated axons of some 4-aminopyridines exposed to higher levels [0.1 to 1mM (9.4 to 94.1. mu.g/mL) ] (Bright, 1989; Bowe et al, 1987; Targ and Kocsis, 1985). Similar effects at lower concentrations (on susceptible neurons or nerve endings) may explain paresthesia and pain in the area of intravenous infusion, which is reported in human individuals as a side effect of clinical exposure to 4-aminopyridine.

Absorb (absorb)4-aminopyridine is rapidly absorbed after oral administration. In the in situ study, 4-aminopyridine was absorbed more rapidly from the small intestine than from the stomach. For the stomach and small intestine, the absorption half-life was 108.8 minutes and 40.2 minutes, respectively.

In animals, peak plasma concentrations occurred within 1 hour of dosing following oral administration (non-sustained release) of 4-aminopyridine (fig. 15). Based on the area under the plasma concentration/time curve (AUC) after administration of 4-aminopyridine (2mg/kg) for i.v. and p.o. administration_(0-∞)) In comparison, the bioavailability of 4-aminopyridine was reported to be about 66.5% in male rats and about 55% in female rats (M2001-03). After oral administration, Although (AUC)_(0-∞)) And body weight, but peak plasma concentrations in females were 38% lower than in males; no difference in AUC values between males and females after i.v. administration.

Using administration in solution as a single oral gavage dose¹⁴C-labeled 4-aminopyridine (1mg/kg) was studied in rats and dogs. Of the two species, the two species are,¹⁴the C4-aminopyridines are all rapidly absorbed. In both species, peak plasma levels were reached within 0.5 to 1 hour. Peak plasma levels (C) after equivalent doses based on mg/kg_max) And the extent of absorption, as reflected by AUC, is about four times higher in dogs than in rats. In these studies, there were no significant gender differences in any of the species. These results are summarized in table 1.

Table 1: single oral administration¹⁴Data summarises of the uptake after 1mg/kg of C-4-aminopyridine in rats and dogs (study numbers HWI 6379-101 and HWI 6379-102)

1. At each point in time

When administered orally, 4-aminopyridine is completely absorbed from the gastrointestinal tract. The absolute bioavailability of IR tablets of both formulations was reported to be 95% (Uges et al, 1982). The absolute bioavailability of the aminopyridine-SR tablets was not evaluated, but the relative bioavailability (compared to oral aqueous solution) was 95%. Absorption is rapid unless administered in some circumstances to achieve delayed release. Such a situation may be included in a modified matrix comprising 4-AP (e.g., fampridine-SR), or in a capsule coated with any form of 4-AP (sustained or immediate release) that achieves delayed release of its contents.

When a single 10mg dose of the aminopyridine-SR tablet was administered to healthy volunteers in the fasted state, the mean peak concentration ranged from 17.3ng/mL to 21.6ng/mL in different studies, occurring 3 to 4 hours after administration (T.sub._max). In contrast, the same 10mg dose of 4-aminopyridine oral solution achieved C_maxIs 42.7ng/mL, occurring at about 1.1 hour after dose administration. The exposure increases proportionally with dose (linear kinetics), while the steady state maximum concentration is about 29-37% higher than a single dose.

Table 2 illustrates the dose ratio of the 10mg and 25mg single doses, and the relative bioequivalence of the solid oral dosage form and oral solution.

Table 2: results of a relative bioavailability/bioequivalence summary study in healthy adult volunteers (data N ═ 26)

The dose ratios of the exposures following administration of a single dose of aminopyridine-SR are illustrated in table 3. The pharmacokinetic profile following administration of multiple doses of aminopyridine-SR is illustrated in table 4.

Table 3: dose-normalized pharmacokinetic parameter values (mean + -SEM) following single oral administration of aminopyridine-SR tablets to MS patients

^*Standardized to 5mg dose.

Table 4: pharmacokinetic parameter values (mean and 95% CI) after multiple oral doses of aminopyridine-SR tablets (40 mg/day, 20mg b.i.d.) in 20 patients with MS

NE is not evaluable

Distribution ofIn rats, steady-state volume of distribution (V)_dss) Has been reported to be approximately systemic (unadjusted with bioavailability). V in females following administration of a single p.o. dose of 4-aminopyridine (2mg/kg) to male and female rats_dss13% lower than males (1094.4 mL in males and 947.5mL in females); however, the difference is not statistically significant. Furthermore, there was no difference (2%) between males and females when adjusted for differences in body weight.

In a single dose study, p.o. administration to rats¹⁴C-labeled 4-aminopyridine (1 mg/kg). At 1, 3, 8 and 24 hours post-dose, 3 animals were sacrificed at each time point. Blood was collected and tissues were excised for radioactivity determination. Radioactivity was measured in all collected tissues at a time approximately consistent with peak plasma concentrations 1 hour after dosing. The amounts represent a small proportion of the dose; however, the total amount was only 58.3% of the dose. The highest concentrations were in liver (2.6%), kidney (1.6%) and blood (0.7%); 51% of the radioactivity was in the cadavers (mainly gastrointestinal tract and musculoskeletal system). Range of half-lives excluded from tissueFrom 1.1 to 2.0 hours. The amount of radioactivity detected in all tissues 3 hours after administration was negligible (except for cadavers, which contained 15.4% of the radioactive dose).

In vitro studies were performed in rat and dog plasma to assess binding of plasma proteins. 4-aminopyridine concentrations of 5, 50 or 500ng/mL were used. At all three concentrations tested, 4-aminopyridine did not bind to a large extent and had a high free drug fraction. After the 4 hour dialysis period, the mean percentage of free drug ranged from 73 to 94% in rat plasma and 88 to 97% in dog plasma.

4-aminopyridine did not bind to plasma proteins to a large extent (97 to 99%). A single 20mg intravenous dose was administered, with an average Vd of 2.6L/kg, which greatly exceeded the total body fluid (Uges et al, 1982), similar to the values calculated in healthy volunteers and SCI patients receiving aminopyridine-SR tablets. The plasma concentration-time profile is one of two or three chambers with a rapid initial distribution period. There are measurable levels in saliva.

In the case of rats,¹⁴c-labeled 4-aminopyridine was detected in the brain and cerebellum at tissue/blood ratios of 3.07 and 1.48, respectively, indicating that 4-aminopyridine crossed the blood-brain barrier after oral administration. The rate of 4-aminopyridine exclusion from the brain was similar to that from the blood. Specifically, the half-lives of 4-aminopyridine exclusion from brain tissue (cerebellum and brain) and blood were similar (1.24, 1.63, and 1.21 hours, respectively).

ToxicologyIn single and repeated dose toxicity studies, the dosing regimen greatly affects the rate of side effects. Clinical signs appeared similar after large single doses or repeated lower doses in all species studied and included tremor, convulsions, ataxia, dyspnea, mydriasis, collapse, abnormal vocalization, enhanced respiration, excessive salivation, gait abnormalities, and hyperexcitability and deficits. These clinical signs are deliberate and represent an aggravated pharmacological effect of 4-aminopyridine。

In controlled clinical studies involving the use of 4-aminopyridine, the most common adverse events of the body system occurred in the nervous system, "whole body" and digestive system. Dizziness, insomnia, paresthesia, pain, headache and weakness are the most common adverse events of the nervous system, while nausea is the most commonly reported event in the digestive category.

In MS patients and other populations including spinal cord injuries, the most common treatment-related adverse events reported with aminopyridine-SR can be generally classified as excitatory effects in the nervous system, consistent with the potassium channel blocking activity of the compound. These adverse events include vertigo, paresthesia, insomnia, balance disorders, anxiety, confusion, and epilepsy. While the increased incidence of such events appears to be moderately dose-related, the sensitivity of individuals is quite variable. As a result of disease pathology, it appears that the threshold for epilepsy is lower in people with potentially MS than in people with spinal cord injury; this may be due to the channel blocking nature of the drug interacting with MS brain pathology in certain individuals.

Formulation and applicationThe parenteral compositions are particularly advantageously formulated in dosage unit form, are easy to administer, and are uniform in dosage. Dosage unit form as used herein refers to physically discrete units suitable for administration to the individual to be treated; each unit containing a predetermined amount of therapeutic compound calculated to produce the desired therapeutic effect in association with any pharmaceutical carrier. Administration may be in the form of a single dosage unit, or administration may be in the form of multiple dosage units, including the simultaneous administration of different amounts of the unit dose.

In general, the dosage unit forms of the invention are determined by, and are directly dependent on, the unique characteristics of the therapeutic compound and the particular therapeutic effect to be achieved in a given patient or patient population. The unit dosage form may be a tablet, capsule, aliquot; the unit dosage form may be provided as a blister pack containing one or more doses. In certain administration procedures, a patient may use more than one single unit dose at a time, for example eating two capsules or two tablets contained in different bubbles in a blister pack.

The active compound is administered in a therapeutically effective amount sufficient to treat a condition associated with a particular state in the patient. A "therapeutically effective amount" preferably reduces or ameliorates the symptoms of the condition or the condition itself in a patient by at least about 20%, more preferably by at least about 40%, even more preferably by at least about 60%, and even more preferably by at least about 80%, relative to an untreated individual. The efficacy of a compound can be based on an assessment in an animal model system that can predict the efficacy of treatment of the disease in humans, such as the model systems described herein. The efficacy of a compound can be based on results obtained in a standard population, e.g., results from clinical trials.

The actual dose of 4-AP to be administered to an individual can be determined by physical and physiological factors such as age, sex, weight, severity of the condition, type of disease being treated, previous or concurrent therapeutic intervention, the individual's underlying condition, and the route of administration. Alternatively, substantially all patients may be provided with a standard amount, which is typically derived from studies in a standard population, e.g., data from human individuals in clinical trials. These factors may be determined by skilled artisans, such as health care providers, drug prescribers, doctors, pharmacists, and the like (collectively "practitioners"). In certain embodiments, the practitioner responsible for administration may determine the concentration of the active ingredient in the composition and the appropriate dosage for the individual. In certain embodiments, the dosage may be adjusted by an independent physician, if any complications arise. In certain embodiments, the same dose is administered to all patients (regardless of MS classification, temperature sensitivity, disease duration, progression status, etc.), which amount is found to be safe and effective in a standard reference population.

The sustained release formulations and compositions of the present invention exhibit a desired release profile, which may be termed the maximum plasma concentration (C) of the drug or active agent at steady state_maxSS) And minimum plasma concentration (C) of the drug or active agent at steady state_minSS) To describe. Steady state is observed when the rate of administration (absorption) and the rate of exclusion of the drug or active agent are equal. C_maxSSAnd C_minSSRatio (C) of_maxSS∶C_minSS) Can be observed from C_maxSSAnd C_minSSAnd (4) calculating. In addition, the formulations and compositions of the present invention exhibit desirable release profiles, which may be termed the mean maximum plasma concentration (Cmax) of the drug or active agent at steady state_avSS) To describe.

Sustained release 4-aminopyridine compositions exhibiting C for twice daily (BID) or once daily (QD) administration as set forth herein_maxSS∶C_minSSThe ratio is about 1.0 to 3.5. In alternative embodiments, for a twice daily (BID) or once daily (QD) administration, the sustained release formulation comprises from about 1.5 to about 3.0C_maxSS∶C_minSSA ratio. In another preferred embodiment, for twice daily (BID) or once daily (QD) administration, C_maxSS∶C_minSSThe ratio is about 2.0 to about 3.0. As one of ordinary skill in the art readily understands, C occurs when plasma levels drop as re-administration occurs_minSSOccurs when the drug is administered again. The foregoing can be exemplified by reference to fig. 16, which is a steady state pharmacokinetic profile of sustained release 4 AP.

A further aspect is a sustained release composition comprising a sustained release matrix and an aminopyridine, wherein the composition provides a C of about 15ng/ml to about 35ng/ml_avSSThe value is obtained. In a further aspect, sustained release tablets comprising a sustained release matrix and an aminopyridine exhibiting a C of about 20ng/ml to about 35ng/ml are provided_maxSSThe value is obtained. Pharmacokinetic profiles of Sustained Release Aminopyridine compositions and methods of treating various neurological disorders Co-pending U.S. application Ser. No. 11/102,559 entitled "Stable Formulations of Aminoprydines and Uses Thereof, filed on 17.4.2004 and U.S. application Ser. No. 11/010,828 entitled" Sustanated Release Aminopyridine Composition ", filed on 13.12.2004The contents of which are incorporated herein by reference in their entirety.

Reagent kitThe kit comprises an exemplary embodiment of the invention. The kit may comprise one external receptacle or container configured to hold one or more internal receptacles/containers, instruments and/or instructions. In accordance with the present invention, the device may comprise means for administering a drug, such as a patch, an inhalation device, a fluid container cup, a syringe or a needle. The composition of the invention may be contained within some of the receptacles or containers of the invention. The receptacle of the present invention may contain a sufficient amount of the composition of the present invention for multiple doses, or may be a unit or single dosage form.

The kits of the invention generally comprise instructions for administration according to the invention. Any mode of administration supported herein may form part of the specification. In one embodiment, the instructions indicate that the composition of the invention is to be taken twice daily. The instructions may be affixed to any container/receptacle of the present invention. Alternatively, the instructions may be printed or embossed on/in or constituting components of the receptacle of the invention.

The kit may also contain instructions for using the kit components and using any other reagents not contained in the kit. Such reagents are contemplated to be embodiments of the kits of the invention. However, such kits are not limited to the specific items identified above, and may comprise any agent used, directly or indirectly, in the treatment of cognitive disorders or cognitive impairment.

In one embodiment, the kit of the invention comprises, for example, a bottle containing the medicament of the invention, together with information on administration and/or safety; this information may be affixed to the bottle, or provided simultaneously, so that the patient obtains the bottle and the instructions substantially simultaneously. In one embodiment, the kit of the invention comprises, for example, a blister pack containing the medicament of the invention, together with information on administration and/or safety; this information may be affixed to the bottle, or provided simultaneously, so that the patient obtains the bottle and the instructions substantially simultaneously. Typically, the medicaments of the invention in the kit are in unit dosage form.

Durable treatmentEmbodiments of the invention include methods of effectively treating multiple sclerosis in a patient over a chronic, extended, protracted, or sustained period; this is also referred to as "permanent" treatment or "permanent" treatment method; this is also referred to as "continuous" treatment or "continuous" treatment method. Another embodiment of the invention relates to a method of maintaining an improvement in symptoms of multiple sclerosis in a patient comprising administering to said patient a therapeutically effective amount of 4-aminopyridine after previously said patient achieved an improvement in symptoms of multiple sclerosis in the course of continuous or prior administration of 4-aminopyridine. Any such method comprises administering to the patient a therapeutically effective amount of 4-aminopyridine for an extended, protracted, sustained or chronic period (as used herein, extended, protracted, sustained, chronic is synonymous unless the context clearly indicates otherwise).

In certain embodiments, the extended, protracted, sustained, or chronic period is at least or more than 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, or 22 weeks; 3. 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 months; or 1, 2, 3, 4, 5, 6, or more than 5 years. In certain embodiments, the extended, protracted, chronic, or sustained period is the lifetime of the patient. These methods may also include administering a therapeutic level (e.g., C) in accordance with the present invention_minSSOr average C_minSS) Or range (e.g. C)_minSSRange or average C_minSSReference range of values) or 4-aminopyridine to a therapeutic level (e.g., C)_minSSOr average C_minSS) Or range (e.g. C)_minSSRange or average C_minSSReference range of values).

In certain embodiments, the symptom of improvement is not walking, not walking ability, not increased or improved walking speed, not cognition and/or not spasticity. In certain embodiments, one or more of these parameters may or may not be specifically excluded.

In certain embodiments, the therapeutically effective amount of 4-aminopyridine is 10mg in a sustained release composition for twice daily administration. In certain embodiments, the sustained release composition may be administered twice daily. In certain embodiments, the sustained release composition may be administered once daily. These methods may also comprise administering a therapeutic level (e.g., C) in accordance with the present invention_minSS) Or range (e.g. C)_minSSRange) or administering 4-aminopyridine to therapeutic levels (e.g., C)_minSS) Or range (e.g. C)_minSSRange). Certain embodiments relate to the use of 4-aminopyridine to treat a demyelinating condition for at least 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, or 22 weeks; 3. 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 months; or 1, 2, 3, 4, 5, 6, or more than 5 years. Still further embodiments relate to the use of 4-aminopyridine for the preparation of a medicament or therapeutic agent or formulation for the chronic or permanent treatment of demyelinating conditions or multiple sclerosis or traumatic neuronal injury.

A further embodiment of the invention relates to a method of achieving a sustained or relatively sustained improvement in MS symptoms in a patient suffering from multiple sclerosis, comprising continuously administering to the patient a therapeutically effective amount of 4-aminopyridine for an extended period of time. Improvement is generally defined relative to a control or standard amount or value, it being understood that there is often progressive decline in patients with a disease such as multiple sclerosis, and thus an increase or relative increase may be suitably considered relative to the decline in function that accompanies the intrinsic progression of multiple sclerosis pathology.

In certain embodiments, the therapeutically effective amount of 4-aminopyridine is 10mg in a sustained release composition. In certain embodiments, the sustained release composition may be administered twice daily. In thatIn certain embodiments, the sustained release composition may be administered once daily. These methods may also comprise administering a therapeutic level (e.g., not less than C) according to the invention_minSS) Or range (e.g. at C)_minSS-C_maxSSIn range) or administering 4-aminopyridine to a therapeutic level (e.g., not less than C)_minSS) Or range (e.g. at C)_minSS-C_maxSSWithin range).

The methods of the invention also include achieving sustained improvement in MS symptoms in a patient comprising continuously administering to the patient a therapeutically effective amount of 4-aminopyridine for an extended period of time. This sustained improvement may be relatively increased when there is an ongoing increase in percent improvement relative to the reference or standard population, or it may be relatively variable when there is a fluctuating percent improvement relative to the reference or standard population, such that there is a tendency to perform better than the reference group; when improving the relative change, this may include periods when the individual patient performs worse relative to the reference or standard population.

Combination therapyThe compositions and methods of the invention may be used in a number of therapeutic or prophylactic applications. In order to increase the effectiveness of treatment with a composition of the invention, e.g., aminopyridine, or to increase the protective nature of another treatment (second treatment), it may be desirable to combine these compositions and methods with other agents and methods that are effective in the treatment, amelioration or prevention of diseases and pathological conditions, such as disorders or damage resulting from demyelination of nerve cells.

Administration of the compositions of the invention to an individual will follow the general procedure for administration described herein, and the general procedure for administration of a particular second treatment will also be followed, with the toxicity of the treatment, if any, being taken into account. The necessary repetition of the treatment cycle is expected. It is also contemplated that various standard treatments may be used in combination with the described treatments.

Various combinations may be used; for example, where the aminopyridine or derivative or analogue thereof is "a" and the second treatment (e.g. an immune system modulator often used in MS) is "B", non-limiting combination cycles include (these are exemplary only and the order may be in a forward or backward direction):

A/B/A B/A/B B/B/A A/A/B A/B/B B/A/A A/B/B/B B/A/B/BB/B/B/A B/B/A/B A/A/B/B A/B/A/B A/B/B/A B/B/A/A B/A/B/AB/A/A/B A/A/A/B B/A/A/A A/B/A/A A/A/B/A AB/AB A/AB AB/BAB A/B AB/AB/AB AB/B/B AB/B/AB AB/A/A

examples

Example 1: long term use of 4-AP, MS-F203 extension study (MS-F203EXT)

An intermediate assessment of efficacy and safety of oral sustained release fampridine (fampridine-SR) was obtained in Multiple Sclerosis (MS) patients who were involved in an ongoing open label extension study.

Background: phase 3 studies of aminopyridine in MS (MS-F203) showed an improvement in walking ability. This extended study (MS-F203EXT) monitored the efficacy and safety of patients from MS-F203 during open label treatment. Designing/method: patients were treated with 10mg of aminopyridine bid and clinically evaluated at weeks 2, 14 and 26 and every 6 months thereafter. The qualification criteria include: an explicit MS; age 18-70 years; and when the MS-F203 is screened, the time of 25 feet walking (T25FW) is timed for 8-45 seconds. Efficacy was analyzed by extending the proportion of timed walking responders (ETWR) who walked faster than their fastest untreated rate during most visits.

The interim data from the long-term extended study (MS-F203-EXT) of the phase 3 aminopyridine-SR trial (MS-F203) showed that 24.9% of the extended study participants reached the Extended Timed Walking Responder (ETWR) criteria after one year of treatment and furthermore showed improved walking speed over a period of at least two years. In addition, the safety profile of aminopyridine-SR observed within two years in this study was consistent with the previous placebo-controlled trial.

Before the extension study, a phase 3 study of 4-aminopyridine in MS (MS-F203) showed an improvement in walking ability; MS-F203 is a double-blind phase 3 study. In MS-F203, patients were randomized to 10mg bid aminopyridine-SR or placebo in a 3: 1 ratio. The primary result is a consistent improvement in walking speed (timed walk response) over a timed 25 foot walk.

Design/method: MS-F203EXT monitors efficacy and safety during open label treatment of patients from MS-F203. Patients were treated with 10mg of aminopyridine bid and clinically evaluated at weeks 2, 14 and 26 and every 6 months thereafter. The qualification criteria include: an explicit MS; age 18-70 years; and when the MS-F203 is screened, the time of 25 feet walking (T25FW) is timed for 8-45 seconds. Efficacy was analyzed by extending the proportion of timed walking responders (ETWR) who walked faster than their fastest untreated rate during most visits. The MS-F203EXT study was performed until the time of this application. At each visit, a safety assessment, a timed 25 foot walk assessment, a clinician and individual global impression were made. EDSS evaluations were performed every two years. The timeline and exposure of the MS-F203EXT study (interim data by 2008. 11/30) are as follows: the first patient participated in 2005 on 12/13. The average exposure was 2.1 years (ranging from 9 days to 3 years). The total exposure was 565 patient-years.

In a 14-week placebo-controlled MS-F203 study, 34.8% of the individuals in the fampridine-SR group achieved the criteria for outcome defined as a timed walking responder compared to 8.3% of the individuals in the placebo group. After the placebo-controlled study, 269 of the 283 participants who completed the study (the 269 included those defined as time-walk responders, non-responders, and placebo participants) participated in an open-label extension study (MS-F203 EXT). All participants in the extended study were treated twice daily with 10mg fampridine-SR and clinically evaluated at weeks 2, 14, 26, 52, 78 and 104.

Of the 269 patients who completed MS-F203 and participated in MS-F203EXT, 263 had an assessment of at least one treatment. At the time of this interim analysis, patients had been treated for a maximum of 2.6 years (average exposure of 1.9 years), 196 were still under treatment, 24 were discontinued from adverse events, and 59 experienced at least one severe adverse event, most commonly a relapse of MS. A total of 66 (24.9%) patients were ETWR and showed an average improvement in walking speed of > 30% at each visit within the first year of treatment. By 24 months, the mean improvement decreased to 22%. In contrast, the extended timed walk non-responders showed a 8% decline in the average T25FW speed over two years. There was a statistically significant improvement (p < 0.005) in the individual and clinician global impression scores of ETWR compared to non-responders.

In an extended study, timed walk response was measured using a timed 25 foot walk (T25W). Extended Timed Walking Responders (ETWR) were defined as the most rapidly walking in the first four open-labeled visits (weeks 2, 14, 26 and 52) compared to the fastest untreated speed taken among measurements at five different time points during the placebo-controlled trial and re-measurements at the start of the extended study.

At the interim analysis, participants had been treated for a maximum of 3 years, with an average exposure of 2.1 years and a total exposure of 565 patient-years. A total of 187 (69.7%) of 269 individuals enrolled in the extension trial remained on at the time of the interim analysis. More than half of the study participants were diagnosed with secondary progressive MS (52.8%), the remainder were diagnosed with relapsing remitting MS (28.6%), primary progressive MS (14.9%) and progressive relapsing (3.7%).

ResultsA total of 66 out of 269 study participants (24.9%) were Extended Timed Walking Responders (ETWR) after one year of twice daily treatment with 10mg fampridine-SR. After 12 months of treatment, ETWR showed an average improvement in walking speed of > 30% compared to their best untreated speed, and 22% at 24 months. Extended timing walking non-responders showed a 8% decline in average walking speed over 24 months. Patients and clinics of ETWR compared to non-respondersThere was also a statistically significant improvement in physician global impression score (p < 0.005).

Among the participants defined as timed walking responders in the placebo-controlled trial, 42.9% achieved ETWR criteria after one year in the extended study. In addition, 16.2% of the individuals receiving placebo achieved ETWR in extension in the placebo-controlled MS-F203 test, while 16.2% of the individuals receiving placebo achieved ETWR in the placebo-controlled test. Clearly, 19.7% of the participants defined as time walking non-responders later reached the ETWR criteria in the extension in the placebo-controlled MS-F203 trial.

At the start of the placebo-controlled trial, the overall disability level was assessed using the Expanded Disability Status Score (EDSS) for all study participants, and then assessed again two years later in the extended study. At baseline, the mean EDSS score was 5.76, representing significant disability. After two years in the extended study, the EDSS baseline change in ETWR was-0.1 (p ═ 0.018) compared to +0.4 in non-responders. An increase in EDSS score indicates worsening disability.

ConclusionRetention in open-label studies was 82.9% after one year and 75% after two years. In addition, a sustained walking speed improvement was seen in the responder group after two years. MS patients treated with 4-aminopyridine showed consistently improved and clinically meaningful walking speeds during 2 years of open label treatment. This study provides the first evidence that treatment with 4-aminopyridine has such long-term efficacy. No new security issues arise.

Thus, there is a high retention rate in open label studies: 82.9% in 1 year and 75.0% in 2 years. A subgroup of patients experienced a sustained improvement in walking speed within 2 years. There is no new security signal. At 10mg bid, the incidence of epilepsy was consistent with the expected background rate and other MS experimental experience.

It can be seen that the long-term use of aminopyridine-SR is safe and useful. In particular, the drug was found to be useful for consistent improvement in walking speed (timed walking response) in, for example, timed 25 foot walks.

These long-term data for aminopyridine-SR are important because this drug is used as a chronic treatment for people with MS. The data indicate that fampridine-SR produces a sustained clinically meaningful improvement in walking speed over a two-year period for a subpopulation of people with MS.

A subset of MS patients treated with fampridine showed consistently improved walking speed during the 2 year open label treatment period, an improvement that was considered clinically significant. This is the first published data in the art to demonstrate the long-term efficacy and safe and clinically meaningful treatment of aminopyridine. No new security issues arise.

In further detail: MSF-203EXT

This is an extended study of long-term multicenter open-label sustained treatment with aminopyridine-SR. The target population consisted of patients throughout the united states and canada who had been diagnosed with multiple sclerosis and had been involved in the MS-F203 study.

A total of 269 patients were enrolled and included in the study. Patients were screened for the study at the last visit (visit 8) of the MS-F203 study, and when they met the inclusion and exclusion criteria, the open-label investigational drug of MS-F203EXT was dispensed at that visit. If a patient is not screened for a MS-F203 study at the same time that the last visit to the study was completed, a separate full screening visit is required at the time of study entry. Patients eligible for this screening visit are required to return an additional visit (visit 0) within two weeks to receive their first open label study medication. This schedule for subsequent visits is the same for all patients. The patient returned 2 weeks later for visit 1, and then 12 weeks later for visit 2. Visit 3 occurred 12 weeks after visit 2. Thereafter, the patient appeared every 26 weeks with approximately 8 and 16 weeks of each telephone visit after each clinical visit. At the study endpoint, the patient returned to his next scheduled routine 26 week visit (last visit) and a four week follow-up period without the investigational drug was started. They returned for follow-up evaluation (follow-up visit) in 4 weeks.

During the study, patients consumed one tablet every 12 hours, at approximately the same time each day. All patients received a stable therapeutic dose of aminopyridine-SR, 10mg BID (20 mg/day). The functional assessment comprises

Walk 25 feet in time

Clinician global impression Change (CGI)

Individual Global impression (SGI) and

extended Disability Status Score (EDSS)

Safety assessments are based on reported adverse events, physical examinations, clinical laboratory tests, 12-lead ECG and standard EEG tests (requiring all patients to be done at the time of screening for an incoming visit; should be done if the patient has epilepsy). At each clinical visit, the investigator needs to record whether continued study participation will be in line with the patient's greatest benefit. Patients who terminate therapy experience an early termination visit.

Included diagnosis and primary criteria-to be included in the trial, the patient needs to have:

participating in the MS-F203 study (receiving aminopyridine-SR or placebo)

Has already suffered from clinically definite multiple sclerosis as defined by the McDonald criteria, and

male or female, must be at least 18 years old.

Any patient over 70 years of age needs to have good overall health in the judgment of the investigator.

Test product, dose and mode of administration-the test product was a 10mg fampridine SR tablet, administered orally b.i.d. (every 12 hours).

Duration of treatment and estimated patient-annual exposure-this is an ongoing study. Based on ongoing monitoring, 269 patients in the study had on average been exposed to 10mg of aminopyridine-SR b.i.d. for approximately 2.1 years (range 8.5 days, 3.0 years). By the clinical cutoff of 2008, 11, 30 days in this cohort, the estimated exposure was approximately 565 patient-years.

Efficacy-functional and subjective efficacy assessments included a timed 25 foot walk, clinician global impression Change (CGI), and individual global impression (SGI).

Safety-safety assessments included reported adverse events, physical examinations, clinical laboratory tests, vital signs, and 12-lead ECG.

Statistical approach-this is a brief interim analysis in patients with multiple sclerosis to support clinical safety updates for new drug applications for aminopyridine-SR. SAS is used for all computationsVersion 8.2 or more. All study data were from a pooled database updated with a clinical cutoff of day 11, 30. Descriptive statistics were calculated for more than four classes of continuous and ordered variables (n, mean, standard deviation [ SD)]Median, minimum and maximum). The incidence and percentage of all other category variables are tabulated. Percentages are based on the total number of undeleted values. The safety population included all patients who received open-label investigational drugs. This population is used in the analysis of demographic and baseline characteristic data as well as in the analysis of security data. In this study, only one analytical dose group (10mg b.i.d.) was defined. No formal hypothesis testing was performed. A brief safety analysis was performed for the following variables: adverse Events (TEAE) and clinical signs that occurred after treatment: vital signs, laboratory assessments, and ECG parameters.

Patient configuration-attended: n-269; the number of stops was 82 (30.5%) (28 people for adverse events and 54 people for other reasons); the continuation quantity is 187 (69.7%).

Efficacy results-updated efficacy results from ongoing open label studies are provided in a combined comprehensive analytical clinical study report (MS-F-EXT) which includes MS-F202EXT, MS-F203EXT, and MS-F204 EXT. This integrated analysis reports a signal that long-term efficacy of aminopyridine-SR was examined in multiple sclerosis patients.

Safety results-in double-blind placebo-controlled primary study (MS-F203), the most common adverse events (TEAE) in aminopyridine-SR-treated patients were falls, urinary tract infections, dizziness, insomnia, fatigue, nausea, upper respiratory tract infections, weakness, back pain, balance impairment, and headache. In this extended study (MS-F203EXT), the most common adverse events were urinary tract infections, multiple sclerosis relapses, falls, joint pain, weakness, limb pain, nausea, peripheral edema, upper respiratory tract infections, and insomnia. In general, the observed adverse event patterns in this open-label extension study subpopulation were similar to those recorded for patients treated with aminopyridine-SR in a double-blind study. Of the 269 patients treated, 187 remained on by 11/30 of 2008. 28 patients withdrew from the study due to adverse events. In addition, 4 patients were withdrawn for non-compliance, 27 consented to withdrawal, 4 failed to follow-up, and 19 were withdrawn for "other" reasons. 63 patients experienced severe adverse events at some time point in the study, most commonly multiple sclerosis relapses. In addition to adverse event summary tables, patient counts, demographics, and clinical signs: summary tables of laboratory values, vital signs and ECG are found at the end of this text. One patient experienced a complex partial seizure and three patients experienced generalized seizures (convulsions) when taking 10mg of b.i.d. aminopyridine-SR.

This ongoing extensive study provides additional evidence for the long-term efficacy and tolerability of fampridine-SR in multiple sclerosis patients. 70% of patients survived the last 3 years of the study demonstrated that the treatment produced appreciable benefit and safety for some patients and investigators.

Example 2: long term of 4-APExtension study Using-MS-F204 (MS-F204EXT)

This example provides data for an extended study of long-term multicenter open-label sustained treatment with aminopyridine-SR. The target population consisted of patients throughout the United states and Canada who had been diagnosed with multiple sclerosis and had been involved in the MS-F204 study.

A total of 214 patients were enrolled and included in the study. Patients were screened at the last visit of the MS-F204 study (visit 8) and, when they met the inclusion and exclusion criteria, were dispensed open label investigational drugs of MS-F204EXT at that visit. If a patient is not screened at the same time that the last visit of the MS-F204 study was completed, a separate full screening visit is required at the time of study entry. Patients eligible for this screening visit are required to return an additional visit (visit 0) within two weeks to receive their first open label study medication. This schedule for subsequent visits is the same for all patients. The patient returned 2 weeks later for visit 1, and then 12 weeks later for visit 2. Visit 3 occurred 12 weeks after visit 2. Thereafter, the patient appeared every 26 weeks with approximately 8 and 16 weeks of each telephone visit after each clinical visit. At the study endpoint, the patient returned to his next scheduled routine 26 week visit (last visit) and a four week follow-up period without the investigational drug was started. They returned for follow-up evaluation (follow-up visit) in 4 weeks.

During the study, patients consumed one tablet every 12 hours, at approximately the same time each day. All patients received a stable therapeutic dose of aminopyridine-SR, 10mg b.i.d. (20 mg/day).

The functional assessment comprises:

walk 25 feet in time

Clinician global impression Change (CGI)

Individual Global impression (SGI) and

extended Disability Status Score (EDSS)

Safety assessments are based on reported adverse events, physical examinations, clinical laboratory tests, 12-lead ECG and standard EEG tests (requiring all patients to be done at the time of screening for an incoming visit; should be done if the patient has epilepsy). At each clinical visit, the investigator needs to record whether continued study participation is in line with the patient's greatest benefit. Patients who terminate treatment experience an early termination visit.

Inclusion of diagnostic and Primary criteriaTo be included in the trial, the patient needs to have:

participating in the MS-F204 study (receiving aminopyridine-SR or placebo)

male or female, must be at least 18 years old.

Test product, dosage and mode of administrationThe test product was a 10mg fampridine-SR tablet, administered orally b.i.d. (every 12 hours).

Treatment duration and estimated patient-year exposureOn average, 214 patients in the study were exposed to 10mg aminopyridine-SR b.i.d. for approximately 0.9 years (range 7.5 days, 1.3 years). By the clinical cutoff of 2008/11/30 in this cohort, the estimated exposure was approximately 193 patient-years.

Efficacy ofFunctional and subjective efficacy assessments include timed 25 foot walking, clinician global impression Change (CGI) and individual global impression (SGI).

Safety featureSafety assessments include reported adverse events, physical examinations, clinical laboratory tests, vital signs and 12-lead ECG.

Statistical methodAll computations use SASVersion 8.2 or more. All study data were from a pooled database updated with a clinical cutoff of day 11, 30. Descriptive statistics were calculated for more than four classes of continuous and ordered variables (n, mean, standard deviation [ SD)]Median, minimum and maximum). The incidence and percentage of all other category variables are tabulated. Percentages are based on the total number of undeleted values. The safety population included all patients who received open-label investigational drugs. This population is used in the analysis of demographic and baseline characteristic data as well as in the analysis of security data. In this study, only one analytical dose group (10mg b.i.d.) was defined. No formal hypothesis testing was performed. A brief safety analysis was performed for the following variables: adverse Events (TEAEs) and clinical signs that occurred after treatment:

the vital signs,

Laboratory evaluation, and

ECG parameters.

Patient configuration-participating in: n-214; stop number 30 (14.0%) (4 people for adverse events and 26 people for other reasons); the continuation quantity 184 (86.0%).

Safety resultsIn double-blind, placebo-controlled primary studies (MS-F204), the most common adverse events (TEAE) in aminopyridine-SR-treated patients were urinary tract infections, falls, insomnia, headache, weakness, dizziness, nausea, back pain, balance disorders, upper respiratory tract infections, joint pain, nasopharyngitis, and paresthesia. In this extended study (MS-F204EXT), the most common adverse events were falls, urinary tract infections, multiple sclerosis relapses, weakness, balance disorders, joint pain, upper respiratory tract infections, limb pain, nausea, contusion, dizziness, fatigue, and peripheral edema. In general, the adverse event patterns observed in this open-label extension study sub-populationThe formula is similar to the pattern of adverse events recorded for patients treated with aminopyridine-SR in a double-blind study. Of the 214 patients treated, 184 remained on by 2008, month 11, and day 30. 4 patients withdrew from the study due to adverse events. In addition, 15 gave consent for exit, one failed to follow up, and 10 were exited for "other" reasons. 17 patients experienced severe adverse events at some time point in the study, most commonly multiple sclerosis relapses. In addition to adverse event summary tables, patient counts, demographics, and clinical signs: summary tables of laboratory values, vital signs and ECG are found at the end of this text. By day 30, 11 months 2008, there were no reports of epilepsy in the study.

Efficacy resultsUpdated efficacy results from ongoing open label studies are provided in a combined comprehensive analytical clinical study report (MS-F-EXT) including MS-F202EXT, MS-F203EXT and MS-F204 EXT. This integrated analysis reports a signal that long-term efficacy of aminopyridine-SR was examined in multiple sclerosis patients.

This ongoing extensive study provides additional evidence for the long-term efficacy and tolerability of fampridine-SR in patients with multiple sclerosis. 86% of patients survived over 15 months of the study, as seen by the patient and the treating physician, confirmed the benefit and safety of treatment.

Example 3: open-label extension of fampridine-SR tablets in patients with multiple sclerosisMiddle analysis of the study (MS-F203EXT and MS-F204EXT)

This data sets forth a metaphase assessment of the efficacy and safety of aminopyridine-SR in Multiple Sclerosis (MS) patients who were involved in an ongoing open label extension study.

Two phase 3 double-blind studies of fampridine-SR in MS patients (MS-F203 and MS-F204) demonstrated improvement in Walking Speed (WS) using a timed 25 foot walk. These placebo-controlled studies were followed by an open label extension study (MS-F203EXT/MS-F204 EXT).

Design/method: in MS-F203EXT/MS-F204EXT, patients were treated chronically with 10mg bid and clinically evaluated at weeks 2, 14, 26 and every 6 months thereafter. In the double-blind study, patients treated with aminopyridine-SR were classified based on double-blind chronowalking responder (DBTWR) status. DBTWR is defined as a patient with rapid WS in at least three of four double blind efficacy visits compared to the maximal WS in any of 5 untreated visits.

Summary analysisAmong the 224 patients treated with aminopyridine-SR in MS-F203, 197 patients entered the extension study and WS was measured at least once. The WS improvement observed in the double-blind study disappeared after cessation of aminopyridine-SR but recovered at the first efficacy visit of the extension study. The mean change in DBTWR from baseline remained above the original baseline while the non-DBTWR dropped below the original baseline when participating in MS-F2032.5.

The walking speed of MS patients treated with aminopyridine-SR showed a consistent improvement compared to baseline and lasted up to 2.5 years during the open label treatment. No new security signal is present.

Example 4: open label extension study (MSF-202EXT) to evaluate oral aminopyridine-SR inSafety, tolerability and activity in individuals with multiple sclerosis

This is a long-term multicenter open label study with continuous treatment with aminopyridine-SR. The target population consisted of patients throughout the United states and Canada who had been diagnosed with multiple sclerosis and had been involved in the aminopyridine clinical trial sponsored by Acordia or Elan.

A total of 177 patients were enrolled. All patients were screened for visits and, when they met the inclusion and exclusion criteria, returned within 14 days (visit 0) to begin investigation of drug dose gradients (upregulation). Patients appeared once a week for the first 2 weeks and were given a fixed dose of the investigational drug (visit 1 and 2). 4 weeks after the visit 2, the patient appeared (visit 3), and 8 weeks after the visit 3 again (visit 4). Thereafter, the patient appeared every 12 weeks with a telephone visit occurring 6 weeks between each clinical visit. The study interval was then increased to every 26 weeks, with approximately 8 and 16 weeks of telephone visits after each clinical visit. At the study endpoint, the patient returned to his next scheduled routine 26 week visit (last visit) and a four week follow-up period without the investigational drug was started. They returned for follow-up evaluation (follow-up visit) in 4 weeks.

During the study, patients consumed one fampridine-SR tablet every 12 hours, at approximately the same time each day. The patient received 20mg b.i.d. or 15mg b.i.d. aminopyridine-SR. This is reduced to 15mg b.i.d. or 10mg b.i.d. aminopyridine-SR. By the end, the patient received only 10mg b.i.d. aminopyridine-SR (20 mg/day).

The functional assessment comprises:

walk 25 feet in time

Clinician global impression Change (CGI)

Individual global impression (SGI), and

extended Disability Status Score (EDSS)

The safety assessment is based on reported adverse events, physical examinations, clinical laboratory tests, 12-lead ECG and (in a subset of patients) standard EEG tests. At each clinical visit, the investigator needs to record whether continued study participation is in line with the patient's greatest benefit. Patients who terminate therapy experience an early termination visit.

previously enrolled in a study on multiple sclerosis sponsored by Acordia Therapeutics or Elan, and received aminopyridine or placebo

Has suffered from multiple sclerosis, as determined by a major investigator, and

male or female, must be at least 18 years old.

Any patient over 70 years of age needs to have good overall health in the judgment of the investigator. Any female patient with fertility potential, regardless of sexual life, must test negative for urinary pregnancy at the time of screening for an incoming visit.

Test product, dosage and mode of administrationTest products were 10mg, 15mg and 20mg fampridine SR tablets, administered orally b.i.d. (every 12 hours).

Treatment duration and estimated patient-year exposureOn average, 177 patients in the study had been exposed to 10mg aminopyridine-SR b.i.d. for about 2.6 years (range 2 days, 4.5 years). One hundred seventy-five (175) of 177 patients had on average been exposed to 15mg b.i.d. for about 0.6 years (range 2 days, 1 year); on average, 9 out of 177 patients had been exposed to 20mg b.i.d. for approximately 0.2 years (range 15 days, 0.5 years). By the clinical cutoff of 2008, 11, 30 days in this cohort, the estimated exposure was approximately 567 patient-years.

Statistical methodAll computations use SASVersion 8.2 or more. All study data were from a pooled database updated with a clinical cutoff of day 11, 30. Descriptive statistics were calculated for more than four classes of continuous and ordered variables (n, mean, standard deviation [ SD)]Median, minimum and maximum). The incidence and percentage of all other category variables are tabulated. Percentages are based on the total number of undeleted values. The safety population included all patients who received open-label investigational drugs. This population is used in the analysis of demographic and baseline characteristic data as well as in the analysis of security data. The patient may receive 20mg b.i.d. or 15mg b.i.d. of aminopyridine-SR. This is reduced to 15mg b.i.d. or 10mg b.i.d. aminopyridine-SR. By the end, the patient may receive only 10mg b.i.d. of aminopyridine-SR. A brief safety analysis was performed for the following variables: adverse Events (TEAEs) and clinical signs that occurred after treatment: vital signs, laboratory assessments, and ECG parameters.

Patient configuration-participating in: n is 177; the number of stops was 84 (47.5%) (30 people for adverse events and 54 people for other reasons); the amount continued is 93 (52.5%).

Safety resultsThe most common adverse events are urinary tract infections, falls, weakness, multiple sclerosis recurrence, insomnia, headache, muscle spasm, fatigue, upper respiratory tract infections, dizziness, joint pain, muscle twitching, and peripheral edema. In general, the observed adverse event patterns in this open-label extension study subpopulation were similar to those recorded for patients treated with aminopyridine-SR in a double-blind study. In 177 patients treatedIn the middle, 93 people remained on until 2008, month 11 and 30. Thirty patients dropped out of the study due to adverse events. In addition, 2 patients were withdrawn for non-compliance, 32 consented to withdrawal, 3 failed to follow-up, and 17 for "other" reasons. Fifty-eight patients experienced severe adverse events at some time point in the study, most commonly multiple sclerosis relapses. One patient experienced complex partial seizures at 10mg b.i.d. fampridine-SR, while two patients experienced generalized seizures (convulsions) at 15mg b.i.d. dose.

This study provides additional evidence for the long-term efficacy and tolerability of fampridine-SR in patients with multiple sclerosis. Over 50% of patients survived the last 5 years of the study confirmed that the treatment produced perceived benefit and safety for some patients and investigators.

Example 5: three Long term studies (MS-F202EXT, MS-F203EXT, MS-F204EXT)Middle term results of

Three long-term studies (MS-F202EXT, MS-F203EXT, MS-F204EXT) are extensions of the multicenter open-label in the ongoing (to the time of this application) continuous treatment with 4-aminopyridine-SR in patients with clinically definite multiple sclerosis who were enrolled in two phase 3 studies (MSF-203, MSF-204) or the earlier phase 2 study (MS-F202). Efficacy was assessed as a timed 25 foot walk, CGI and SGI (at each visit), and EDSS (assessed every two years).

Table 4 below provides a summary of the studies and a short description of the results of each study. Evaluation of the combined efficacy data for the MS-F202, MS-F203 and MS-F204 studies is presented herein. Given the purely descriptive nature of the data analysis of the extension studies, at the end of this section, these data of all three extension studies were merged together.

MS-F202EXTBy the time of filing, MS-F202EXT was an ongoing long-term multicenter open-label extension study of 4-aminopyridine-SR on-going treatment of patients with clinically definite multiple sclerosis who were previously involved in the study of 4-aminopyridine. Based on clinical monitoring reports, 198 patients were screened by 31/7/2008, and 177 were enrolled, with approximately 98 remaining active. By 31 days 7/2008, approximately 160 patients completed the study for more than 6 months, 145 for more than 1 year, and 90 for more than 4 years. Integrated report MS-F-EXT uses data from all ongoing extended studies with clinical expiration date of 31 days 7 months 2008 to explore the efficacy of 4-aminopyridine-SR with extended open label treatment. The results are summarized herein.

MS-F203EXTBy the time of filing, MS-F203EXT was an ongoing long-term multicenter open-label extension study of 4-aminopyridine-SR on-going treatment of patients with clinically definite multiple sclerosis who were enrolled in the MS-F203 study. Based on clinical monitoring reports, 272 patients were screened by 31/7/2008 with 269 enrolled and approximately 196 remaining active. By 31 days 7/2008, approximately 247 patients in the study completed 6 months, 227 people exceeded 1 year, and 203 people exceeded 2 years. Integrated report MS-F-EXT uses data from all ongoing extended studies with clinical expiration date of 31 days 7 months 2008 to explore the efficacy of 4-aminopyridine-SR with extended open label treatment. The results are summarized herein.

MS-F204EXTBy the time of filing, MS-F204EXT was an ongoing long-term multicenter open-label extension study of 4-aminopyridine-SR on-going treatment of patients with clinically definite multiple sclerosis who participated in the MS-F204 study. Based on clinical monitoring reports, 219 patients were screened by 31 months 7 in 2008, withBit 214 participates and about 190 bits are still active. By 31 days 7 months 2008, a total of 139 completed the study for 6 months. Integrated report MS-F-EXT uses data from all ongoing extended studies with clinical expiration date of 31 days 7 months 2008 to explore the efficacy of 4-aminopyridine-SR with extended open label treatment. The results are summarized herein.

Evidence of sustained efficacy in long-term open label extension studiesA total of 756 patients participated in these three open label long-term extension studies (MS-F202EXT, MS-F203EXT, and MS-F204EXT), with 546 patients completed 6 months and 372 completed more than 1 year by 31 months 7 in 2008, based on clinical monitoring reports. In the longest open study MS-F202EXT, approximately 98 (55%) of 177 patients enrolled were still active in the study, and most of them had completed more than 4 years of open label treatment.

The consolidated report "MS-F-EXT" uses interim data from three ongoing extended studies (MS-F202EXT, MS-F203EXT, and MS-F204EXT), with an interim clinical expiration date of 2008/7/31, exploring the longer term efficacy of 4-aminopyridine-SR. Objects, methods and key results are summarized below.

Purpose of MS-F-EXT: the objective of MS-F-EXT was to analyze the available efficacy data from an ongoing open label safety extension study of 4-aminopyridine-SR in patients diagnosed with multiple sclerosis with a mid-term data expiration date of 31 days 7 months 2008.

Method for MS-F-EXT: this report focused primarily on examining available data in terms of walking speed, individual and clinician global impression to confirm a sustained response to treatment during the ongoing open label extension phase of the study.

Efficacy analysis was based on all individuals who received at least one efficacy measurement in the MS-F202EXT, MS-F203EXT, or MS-F204EXT studies and also participated in the primary double-blind study. For this purpose, equivalent timed walking response criteria were used on the extension study data, where extension timed walking responders were defined as the majority of extension study visits during treatment, patients who showed a faster walking speed than the fastest untreated walking speed recorded prior to open label treatment (i.e., the speed measured at all untreated visits from screening visits of a double-blind primary study to screening visits of an extension study). Data exists in the form of study pairs (primary and extended).

To characterize the efficacy of 4-aminopyridine-SR in the treatment of patients with MS, the following analysis was performed:

1. the incidence of walking responses was chronologically extended in each extension study.

2. The average percent change in walking speed for the responder analysis groups from the primary and extension studies to the double-blind baseline is presented graphically.

3. To verify the clinical significance of the extension timed walk response criteria, the average of the individual global impression (SGI) scores and the average of the Clinician Global Impression (CGI) scores during the respective extension study were compared between extension timed walk responders and non-responders.

4. In addition, the response rates of extended-length timed walks over many years of treatment are summarized in the incidence tables.

5. When available (only every 2 years of evaluation), Expanded Disability Status Scale (EDSS) score changes were compared among the extended timed walking responder groups.

6. An alpha level of 0.05 was used in the analysis. Multiple test corrections were not used.

Observations and findings after chronic/extended/prolonged administration of 4-aminopyridine:

in study MS-F202EXT, a total of 21 (15.7%) patients were classified as extension timing walking responders. A total of 11 (25.6%) 4-aminopyridine-treated time-walking responders from the primary study (MS-F202) continued to become extended time-walking responders; in addition, 6 (9.5%) of 4-aminopyridine-treated chronowalking non-responders from the primary study became extension chronowalking responders, while 4 (14.3%) of placebo-treated patients from the primary study qualified extension chronowalking responders. The percentage of 4-aminopyridine double-blind responders who continued to be extension timing walking responders in 1, 2 and 3 years of the extension study was 25.6%, 23.1% and 22.2%, respectively. For double-blind timed walking non-responders, these numbers were 11.1%, 5.2% and 6.1%, respectively, while for placebo-treated patients 17.9%, 4.6% and 5.3%, respectively.

In the study MS-F203EXT, a total of 66 (24.9%) patients were classified as extended timing walking responders. Of them, 29 (41.4%) of the 4-aminopyridine-treated time-walking responders from the primary study (MS-F203) continued to be extended time-walking responders; in addition, 25 (19.7%) of 4-aminopyridine-treated chronoambulatory non-responders from the primary study became extension chronoambulatory responders, while 12 (17.7%) of placebo-treated patients from the primary study qualified extension chronoambulatory responders. For 4-aminopyridine double-blind responders, the response rates were 42.9% and 36.1% in year one and 2, respectively. For 4-aminopyridine double-blind non-responders, 19.7% and 17.5%, respectively, and for placebo-treated patients 16.2% and 20.8%, respectively.

For all patients in MS-F203EXT, the walking speed of the extended timed walk responders and extended timed walk non-responders was the mean percent change from baseline over the first two year period of the primary and extended studies, plotted in figure 2 below. In the first year of the extension study, the average walking speed of the extended timed walking responder group was slightly more than 30% faster than the baseline walking speed of the double-blind study at each visit of the extension study. Over the course of the year, the average walking speed of extension timed walking non-responders showed a slight change from baseline, with the exception of a slight increase after the first two weeks of dosing (visit 1) and a slight decrease in average at one year (visit 4). In the second year of the extended study, some decline in the improvement in mean walking speed was seen for the timed walking responders, such that the improvement at the baseline of visit 6 was only slightly over 20%. Likewise, by the end of the second year, walking speed of chronoambulatory non-responders decreased by approximately 8% from the baseline of the original double-blind study, consistent with or based on the progressive nature of the underlying disease.

In the study MS-F204EXT, a total of 105 (49.3%) patients were classified as extended timing walk responders. Of them, 35 (71.4%) of the 4-aminopyridine-treated time-lapse walking responders from the primary study (MS-F204) continued to become extended time-lapse walking responders; in addition, 18 (30.0%) of 4-aminopyridine-treated time-lapse non-responders from the primary study became extension time-lapse responders, while 52 (50.0%) of placebo-treated patients from the primary study qualified extension time-lapse responders. Improvement in patients evaluated in the study, occurring over at least or more than 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, or 22 weeks; 3. 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 months; or a treatment period of 1, 2, 3, 4, 5, 6, or more than 5 years.

Thus, using the primary endpoint timing walking response (used in double-blind control primary studies MS-F202, MS-F203, and MS-F204), a consistent improvement in walking speed was seen in an appreciable fraction of patients in the long-term extension studies MS-F202EXT, MS-F203EXT, and MS-F204 EXT. This improvement in extended timing walking responders was stable for at least the first two years of treatment. The improvement in patients devoted to these studies occurred at least or over 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, or 22 weeks; 3. 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 months; or a treatment period of 1, 2, 3, 4, 5, 6, or more than 5 years.

Overall, the improvement in patients devoted to these studies occurred at least or over 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, or 22 weeks; 3. 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 months; or a treatment period of 1, 2, 3, 4, 5, 6, or more than 5 years. These findings further support the improved clinical significance seen in double-blind and extended studies, as well as the validity of criteria used to identify this step-by-step response to treatment.

Table 5 below provides a summary of the primary and secondary efficacy variables in the study MS-F201, MS-F202, MS-F203, and MS-F204.

Table 5: measurement of efficacy and health outcomes for use in placebo-controlled efficacy studies