CS216591A3 - Preparation for treating alzheimer's disease and process for preparing thereof - Google Patents

Description

Field of the Invention

The present invention relates to a composition for treating Alzneimer's disease comprising a synergistic mixture of pnsostigmine and 4-aminopyridine as active ingredient. It is a further object of the invention to provide a pharmaceutical composition. Another object of the invention is to provide a method of treating Alzheimer's disease.

Background Art

Damage to cognitive functions, adaptation to the well-known situations of daily life in old age, is a common diagnosis of dementia. 15.5% Population over 65 and 20% over 80 suffer from one form of dementia. Alzheimer's type of dementia; it is currently a profound professional interest because the disease is associated with prolonging the average age and therefore enjoys great public interest. Such an interest is self-evident because dementia occurs in almost every family. This event, unfortunately, puts the burden of families on both social / emotional and emotional aspects. Compared to 10 trillion in 1982 (Terry and Katzman), $ 34 trillion was spent in 1985 on treating patients suffering from some form of dementia. The number of people associated with this disease exceeded 2.5 million in 1985. ,. E.

Alzneimr's disease was first described by Alois Alzheimer, a German neurologist, in 1906 as a presenile type of dementia. The patient, although only fifty-one, showed severe symptoms of senile dementia. The deterioration was very rapid and the patient died after a few days. After the brain was extracted, Alzheimerpops said that neurofibrils, which are normally arranged in fiber-like form, appear to be a tangled bundle. These neurofibrillary nodules have been described as typical symptoms of non-power called presenile dementia. István Tariska (1965) collected the neuropathological signs of the existence of the disease and pointed out 2 certain symptoms that are diagnostically significant for the differentiation of Alzheimer's and Pick's diseases. In the 1960s, Alzheimer's disease was shown to appear not only in prescription, but also in late age, and generally forms the greater part of senile dementia. The term "senile dementia Alzheimer's type" (SDAT) is generally used. According to this latest theory, there is no difference between Alzheimer's disease and senile dementia, although this theory is sometimes questioned. It has also been found that the existence of a disease is one of many common symptoms. This consideration is associated not only with the development of diagnostics in neurology and psychiatry, but also with the revolutionary development of healthcare in the 20th century. This latter reason results in a prolongation of the human age, but on the other hand, it causes the growth of social and clinical problems of the elderly.

It is well known that presenile and senile dementia are clinically and pathologically similar. Alzheimer's disease can occur at any age, although it usually occurs in people over 50 years of age. In the event of a final diagnosis, the average life expectancy is seven years (McGeer and McGear, 1976).

The morphological symptoms of the disease occur in the neurocortex as well as temporal, parietal and occipital cortex, but symphocytes can also be found in the corpus amygdale and in the hippocampus. 1. intraneurally located neurofibrillary tangles, essentially the appearance of cytosomal neurofilaments. Tariska (1965) is described as diffusely located in certain areas of the brain. 2. intraneuronic granulovakuolar degeneration; and 3. extraneuron senile / neuritic / argentaffin plaques 4. reduction of brain volume and neuron count (about 18%). However, the number of neurons is so high at age over 80 that it is not characteristic of Alzheimer's patients. -λ, ',', ''; Λ - 3 -

The functional symptoms of the disease are as follows: 1. Dementia

A feature of a paretic disorder that is never functional, as in the case of neuropaths and psychopaths, is that it prolongs all memory components. This disorder can be interpreted by severe neurophysiological lesions of organic origin. A characteristic symptom is presbiophrenia, complete memory degeneration: the patient reminds of the events of the day, and even repeated reading seems new to him. The capacity of the memory tracks, the conversion of the short-term memory into the long-term memory, i.e. consolidation is not possible and therefore learning, acquiring new knowledge is not possible. Loss of manual memory necessary for action, leads

to apraxia, such as sewing a button or tying a tie, an unsolvable problem. Early dementia is characterized by the disappearance of the EEG alpha rhythm. Late dementia can be determined by CT scanning. Emotional disturbances, fear and depression can also be attributed in part to frustration caused by congestion. 2. Decrease in intelligence

Another group of symptoms of the disease is the rapid decline in intelligence, i.e. the level of corresponding thinking and the respective common activities, the broader the context, the patient adheres to the details, cannot distinguish the essential from the non-essential. The resolution, the ability to abstract and the combination, as well as the intuition, also collapse. Mental work is becoming increasingly difficult and, at an advanced stage, even simple domestic activities can become possible. Sometimes there is a serious activity disorder, for example, the patient gets up at night and performs a number of unsuitable activities, spreads out the bed again, sweeps, etc. Orientation in time and space and the ability to determine the ego also decreases.

The patient is no longer able to follow the daily situation, the ability of the verbal manifestation that later becomes disruptive (Schneck et al, 1982), i.e. the loss of intellectual function becomes the most typical symptom. Subsequently, disorientation, apathy, total inability of other feelings of depression, paranoid reaction, hallucinations occur in the patient. The patient confuses the seasons and cannot use the calendar. Sometimes they cannot even get to know their own husband or wife, and the utter impossibility of social life appears. The disease is also referred to as " double death " according to an intellectual decline associated with overall physical dissolution.

The above symptoms may be associated with actual psychotic acts such as hallucinations, para-noid reactions, etc. Disorders may occur in the affective / emotion / region: the initial emotional lability becomes increasingly disruptive and eventually falls into complete lethargy and apathy. The result is a gradual breakdown of the personality, and even if the patient is in good physical condition, his condition is close to death. These psychiatric symptoms are followed by neurological, such as lack of restraint, motor weakness, extrapyramidal symptoms and spasms. Eventually, patients completely lose their sensitivity, sense of perception and communication, and slowly become immobile. The ultimate cause of death is generally associated infection or other chronic disease (Schneck et al, 1982).

Alzblemer's disease is very difficult to distinguish from other types of senile dementia. I.e. in old age, dementia can be caused by a variety of diseases, such as arteriosclerosis, apoplexy, tumors, dipsoma, anemia, malnutrition, thyroid deficiency, etc. In these cases, mental degeneration is a secondary process; it is based on other illnesses and treatment is used to cure the original disease. The same is true for the symptoms of Parkinson's disease, progressive paralysis, and senile psychosis. Excluding the above-mentioned symptoms, Alzheimer's disease should be distinguished from Kraepelin's disease and disease-prone taste, which in itself is also a primary dementia. .The different diagnoses of both diseases are more or less detectable by phalography. If the presence of all the above-mentioned diseases can be excluded, the diagnosis of Alzheimer's disease is possible. According to statistics, about 50 /) of senile dementia is Alzheimer's thy - 5 - pu. There are various theories about the origin of this disease: 1. Cholinergic theory

One of the best known and most important chemicals that drives substances is acetylcnoline, which is secreted by cholinergic neurons. The abnormal function of the cholinergic system leads to innumerable diseases. E.g. a deficiency in the functions of coronary cholinergic neurons leads to Alzheimer's disease and myastheniagravis is probably associated with reduced cholinergic transmission of motor nerve endings.

There is neurochemical evidence regarding the continuity of Alzheimer's disease and reduced cholinergic system function. Choline acetyltransferase activity (CAT), an enzyme responsible for acetylcholine synthesis, was apparently lower in brain tissue biopsy and in nucleus basalis (Meynert's nucleus / dissected material) (Bowen et al, 1976). Lower activities were also found in vhippocamp. In addition, an opposite ratio was found between frontal but not parietal, CAT activity and disease (Bowen et al, 1976, Rossor et al, 1984). Therefore, it is correctly concluded that less acetylcholine is excreted in the cortical regions. Neural absorption of choline is also reduced in Alzheimer's disease. The activity of CAT is in proportion to the incidence of senile spots (Perry et al, 1979).

Cholinesterase (ChE) activity is also reduced. It has been shown that there is a close correlation between the degree of dementia and the defective function of the cholinergic system (Perry et al, 1978). The destruction of Nissl colored cells of the basal nucleus, as well as the number of spots, is closely related to prudkostinemoci / Whitehouse et al, 1982 /. In histological tests, 70 & the nuclei are degenerate. Although Perry et al (1982) observed the destruction of cytosomes only secondary. Cholinergic rolet cells have also been verified by immunocytochemistry (Nagai et al, 1983).

The relationship between the cortical cholinergic system (about 50-60% nucleus basalis, 20-40% interneuronal origin) and the alzneimeric disease was verified by observing that in Huntington's disease associated with dementia cardinalis as a clinical sign, CaT activity does not decrease. The binding ability of cerebral muscarinic receptors remains unchanged: there is no difference in H-QNB / quinuclidinylbenzylate / binding and the affinity between brain tissue obtained from a normal patient and a patient who has died from Alzheimer's disease. It should not be noted that no standard result can be expected from this measurement since only 10% of the cerebral neurons are cholinergic and also muscarinic receptors also act on other types of neurons. Accordingly, a change in only 10% of cortical neurons can only result in minimal alteration in the cholinergic system, considering all binding sites. Accordingly, the data obtained on the bark and interpreted as a result of a variation in the function of cholinergic fibers are hardly acceptable. Of course, it is also true that finding unmodified fibers would not mean that the function of cholinergic neurons is unchangeable.

Cholinergic theory is supported by observations showing that the symptoms of Alzheimer's patients with ChE inhibiting Chostostigmine but worsening with scopolamine, and appear to be a close correlation between cortical CAT activity / measured by death and dementia rate (Mountjoy et al, 1984). 2. Noradrenergic Theories In Alzheimer's disease, both dopaminergic ternadrenergic pathways are damaged. DOPA-decarboxylase activity (DOPA-DC) is 80% lower than in Parkinson's disease patients (Bowen and Davison, 1976) and of course also the NA and dopamine content is lower (Gershon and Hermann, 1982, Gottfries, 1985). The DA content is 60% lower in the hypothalamus. Inhibition of DA metabolism in these patients is a lower level of homovanilic acid (HVA) (Gottfries, 1985). Clinically detected parkinsonian symptoms occurring in 50% of cases may be explained by this phenomenon. 1 *. • árfýS; - 7 - 3. Gamma-aminobutyric acid

Mountjoy et al (1984) found that in humans, unlike rats, cerebral GABA levels did not change posthumously. An incoherent relationship was found between GABA levels in various cellular regions and neuropathological changes. 4. Another theory

The existence of the disease is also characterized by, among other neurochemical changes, changes in the content of somatostatin and other neuropeptides. Various methods can be used to treat a disease. Some of these are discussed below: 1. Therapy of acetylcholine precursor

To reduce the defective function of the cholinergic system, choline, a precursor of ACh, is added at large doses (16 g / day). Similarly, phosphatidylcholine (25-100 g / day) is also administered. Most of these treatments have proven ineffective in "double blind" tests (Jones et al, 1983). Similar results were obtained with deanol (Fishman et al, 1981), which is converted to choline in the liver. The inadequacy of these treatments is justified by the fact that choline is present in the neurons in a large excess, and as a result, the deficit seems unlikely. . 2. Cholinesterase blockade In this method of treatment, the breakdown of ACh at the synaptic site is inhibited to increase ACh secretion at a reduced rate. Daviset et al. (1982, 1983) observed a temporary improvement after blockadeolinesterase treatment. Memory tests were used in the experiments. Physostig min, 2,3,3a, 8-tetrahydro-1,3a, 8-trimethylpyrrolo [2,3-b] indol-5-ylmethylcarbamate, proved to be optimal at 6 x 2-2.5 mg / mg doses day. 8

Unfortunately, administration causes various side effects (nausea, vomiting). In other views, cholinesterase blockade improves memory impairment in the first row (Mesulam et al, 1987).

Mohs et al (1985) as well as Hollander et al (1986) demonstrated an improvement in physostigmine administration. In general, however, the improvement is only temporary and temporary (Johns et al). Some scientists believe that this method is ineffective because, in addition to the inadequacy of the cholinergic system, probably other neurochemical changes will also play an important role (Hardy et al, 1985).

Physostigmine was administered to patients suffering from Alzheimer's disease at a dose of 1 to 1.5 mg / day (Davis et al, 1976, Goodnick and Gershon, 1984) and an improvement in cognitive function was observed.

Therefore, a limited function of central noradrenergic, serotoninergic pathways has been described. The emergence of memory disorders is likely to be supported by other transmission systems. Although physostigmine increases in ACh concentration in the synaptic gap, the increasing effect on ACh release by the negative feedback mechanism inhibits the aforementioned effect (Vizy et al, 1985). This inhibition of negative feedback occurs through muscarinic receptors and may be abrogated by atropine. Unfortunately, atropine also inhibits muscarinic receptors by postsynaptic, and although the increasedolinergic transmission is a presynaptic effect, this beneficial effect is inhibited by the postsynaptic effect. This theory is supported by the literal indication that administration of atropine impaired learning and memorizing ability (Watts et al, 1981), while these properties improve with physo-stigmine (Murray and Fibiger, 1985). The efficacy of oral administration of tetrahydroaminoacidin / Tacrin, ΤΉΑ / is also likely to be associated with the effect of cholinesterase blocking / Koopmans, Summers et al, Engl. J. Med., 315. 1241-1245 (M1987_7). Nilsson et al / J. Neural Transm., 70, 357-368 (1987) reported that both Tacrin and physostigmine increase the release of ACh in the cortical segments obtained from patients who died from Alzheimer's disease. A critical review is given in the April issue of the British Medical Journal / “Lancet, 298, 845-846 / 1989/7 Tacrine Multicenter Test was abolished / Jarvik, LF, Alzheimer's disease and Associated Lisorders, J., 123-127 / 1987 / / due to the hepatoic effect of the compound (Wilcock et al, Lancet 1305 (1988)); Arnes et al., 887 (1988)].

Based on all data obtained from biopsy tests of patients suffering from Alzheimer's disease, the following information can be summarized: 1. ACh synthesis is subinhibiting (Sims et al, 1980), 2. The number of M ^ muscarinic receptors is reduced (Mash et al, 1985) 3. Choline acetyltransferase activity is reduced, 4. Posthumous examination of patients who died of Alzheimer's showed that basal nucleus (Meynert's nucleus) was somehow damaged (Whitehouse et al, 1981, Bowen et al, 1976) .

These data conclude that there is a causal link between certain symptoms of Alzheimer's disease / cognitive impairment, cognitive impairment / and cholinergic system deficiency (Lancet, 139-141 (1987)); Cholinergic treatment in Alzheimer’s Diseases: Encouraging results.

It has been found that 4-aminopyridine (4-AP) stimulates the increase in the amount of acetylcholine released (Vizy et al, 1977, Fčldes et al, 1988).

Wessling et al., New England Med. J. (1984) have reported that the administration of 4-aminopyridine in Alzheimer's disease has been shown to be partially effective. Clinical administration of the compound has already been known in the following indications: human botulism intoxication (Bali et al, 1979), in the treatment of multiple sclerosis (Jones et al, 1983, Stefoski et al, 1987) and in antagonizing ketamine-diazepine anesthesia / Agoston et al, 1980. Although Lavidson et al / Biol. Psychiatry, 23, 485-490 (1988) found that 4-aP in a daily dose of 2.5 to 10 mg was ineffective in patients aged ó0-110.

SUMMARY OF THE INVENTION The present invention seeks to provide an improved method of treatment that eliminates the undesirable effects of the aforementioned treatments and finds a pharmaceutical composition that provides efficacy when using low drug concentrations.

BACKGROUND OF THE INVENTION The present invention relates to a pharmaceutical composition comprising a mixture of pnsostigmine and 4-aminopyridine as active ingredient. The composition does not have the disadvantages caused by the inhibition of the negative feedback induced by physostigmine and, at the same time, the total amount of the two components can be substantially lower than the effective amount of urea or 4-aminopyridine when administered individually.

Neurocnemic tests have shown that 4-aminopyridine, an inhibitor of the potassium channel, increases ACh secretion in the cortex (Fdldes et al, 1988) and inhibits negative feedback inhibition, thereby promoting ACh secretion.

Atropine also promotes the release of ACh, resulting in the discontinuation of negative feedback inhibition (see Table 1). In the presence of 4-AP, which itself also has the same effect, atropine did not increase the release of ACh at a higher level, i.e. the value of S2 / S1 did not increase. Therefore, negative feedback did not work in the presence of 4-AP. Similar results were obtained with the discontinuation of the oxotremorine inhibitory effect in the presence of 4-aP (see Table 2). Oxotremorine is a compound that stimulates presynaptic carcinin receptors and also inhibits the release of ACh.

FIG. 1 shows that 4-AP exhibits a greater effect in increasing the release of ACh in the presence of epolinesterase (Pnysostig-min).

These phenomena can be explained by olocation of negative feedback, which otherwise functions more prominently in the presence of a ChE blocker / Vizi et al, J. Pharmac. Exp. Tnerapy, 230, 493-499 (1984) - in the presence of 4-AP and therefore the release of ACh is further promoted. «

Therefore, in the composition of the present composition, physo-stigmine, which was inactive due to increased inhibition of negative feedback, i.e., its own beneficial effect, caused its self-inhibition of negative feedback, increased ACh excretion and prolonged action. A substantially low concentration of physostigmine and 4-aminopyridine is sufficient to restore normal cholinergic transmission, i.e., to improve cognitive impairment. Therefore, at least in part, the most difficult problem caused by Alzheimer's disease, which is the social collapse of a patient, can be improved by treatment according to the invention.

Pavidson et al (1988) administered 4-aminopyridine for 5 days to doses of 5-20 mg / day to patients suffering from Alzheimer's disease, at an average age of 66.1 years, and Wesselin et al (1984) also used oral doses of 20 IU / day for patients with an average age of 84.6 years. Pnysostigmine was Davis et al (1978) used at 3 x 0.5 mg doses.

The composition of the invention consists of a synergistic mixture of phy sostigmine and 4-aminopyridine as active ingredient. The ratio of the components in the mixture can be varied within a wide range, preferably 1: 1 to 1: 20. Of course, the above preferred ratio may be exceeded in both directions. A suitable weight ratio is 1: 2 to 1: 10, most preferably 1: 5.

A preferred oral dosage unit comprises, for example, 0.2 mg physostigmine and 1 mg 4-aminopyridine, the daily dose being essentially 3 dosing units

The compositions may be prepared by methods known in the pharmaceutical art, e.g., by mixing the two active ingredients with customary formulation aids and shaping the composition into suitable dosage forms.

The invention also relates to a method of treating Alzheimer's disease comprising administering to a patient pnysostigmine and 4-amino-pyridine. Clinical tests have shown that the following components and preferred doses should be used: 1. Physostigmin salycilicum (Ph.Hg.VII), preferred dosage: 3 x 0.2 mg p.os. 4-aminopyridine (Pymadin, Pharmachim, Bulgaria), 3 x 1 mg p.os., preferably both components are administered together.

If necessary, the dose of 4-aminopyridine may be increased to 2 mg.

Clinical trials conducted on more than 200 patients have shown that partial inhibition of the potassium channel by small doses of 4-AP stops the modulation of the negative feedback of the transmitter, which in turn results in increased release of ACna noradrenaline, without typical side effects.

A small dose of physostigmine causes a partial inhibition of the cholinesterase, but due to partial inhibition of the potassium channel, the negative feedback, i.e. the self-inhibiting effect of ACh on release, is eliminated. This effect is clearly shown in Fig. 1.

Table 1 1 * 3

Rat Frontal Crust, Release of H-ACh in the presence of pnysostig minine Additive S2 / S1 without 0.83 - 0.05Atropin 0.5µmM 1.64-0.074-aminopyridine 40µM 2.36 - 0.134-aminopyridine 40µM +

Atropin 0.5 / UM 2.52 - 0.16 13 -

Table 2 in β

Rat Frontal Cortex, H-ACh Release

Oxotremorine free S2 / S1 additive 0.3 µMoxotremorine 3.0 µM 4-aminopyridine 40 µM 4-aminopyridine 40 µM + oxotremorine 4-aminopyridine 40 µM + oxotremorine 0.85 - 0.070.48 - 0.030.22 - 0.021, 53 - 0.10 0.3 zuM 1.47 - 0.12 3.0 / UM 1.42 - 0.11

Note: 4-Aminopyridine inhibits the oxotremorinflammatory inhibitory effect of α-H-ACh release. 4

Claims (6)

14 PATENT CLAIMS A pharmaceutical composition for the treatment of Alzheimer's disease comprising a synergistic mixture of physostigmine and 4-aminopyridine as an active ingredient. Composition according to claim 1, characterized in that the weight ratio of physostigmine to 4-aminopyridine is 1: 1 to 1: 20. 3. The composition of claim 1 or 2 wherein the weight ratio of pnsostigmine to 4-aminopyridinium is 1: 5. 4. A process for preparing a pharmaceutical composition against Alzheimer's disease, comprising mixing a synergistic mixture of physostigmine and 4-aminopyridine with a pharmaceutically acceptable carrier. 5. A method of treating Alzheimer's disease comprising administering to the patient an effective amount of physostigin and 4-aminopyridine. 6. A method according to claim 5, wherein physostigmine is used at a dosage of 0.4 to 0.5 mg / day and 4-aminopyridine at a dose of 2-4 mg / day.