"USE OF AMMONIUM CHLORIDE IN THERAPY"

The present invention relates to a method for the pharmaceutical treatment of hepatic failure and necrosis, which is caused by various toxic agents, and for the treatment of viral infections or other diseases, specifically tumors, that can be treated with interferons .

There are numerous pathologic and toxic conditions that lead to a degenerative malfunction of the liver. Among these are hepatitis C (one-third of the infected patients evolve to hepatic cirrhosis) , chronic hepatitis B a n d D, autoimmune hepatitis, non-alcoholic steatohepatitis, sclerosant cholangitis, Wilson's disease, Epstein-Barr virus infection and liver carcinoma .

As regards toxic conditions, the most common and relevant one is the one that occurs due to abuse of alcohol. Other toxic conditions are due to drugs and chemical hepatotoxic agents that may lead to hepatic necrosis, such as the poison of certain mushrooms (for example, Amanita falloides) .

Interferons are very important in the treatment of RNA virus infections. Interferons are known to display antiviral, antiseptic and anticancer properties when administered as a drug.

More than 50% of hepatitis C patients treated with interferon respond with viral elimination (sustained virological response) , better blood tests and better liver histology (detected on biopsy) . There is some evidence that administering interferon immediately following infection can prevent chronic hepatitis C.

However, patients infected by HCV often do not display symptoms until months or years after infection and this makes early treatment difficult.

Moreover, in case the infection is caused by Hepatitis C virus genotype 1, around 70% of patients is not responding to the interferon therapy.

Interferons (interferon beta-la and interferon beta- Ib) are also used in the treatment and control of multiple sclerosis, an autoimmune disorder.

Interferon is also used as a treatment for some types of cancer. It is used to treat cancer of the kidney, malignant melanoma and carcinoid tumours. It is also used sometimes to treat certain types of lymphoma and leukaemia.

When a large part of the hepatic parenchyma gets necrotized, the hepatic function decreases and may quickly lead to the death of the patient. Nowadays there are no special treatments able to solve the hepatic necrosis problem and the patients that suffer from these degenerative diseases have a limited prognosis in relation to the survival time.

NH ₄ Cl is a water-soluble inorganic salt, which is used for the treatment of hypochloremic metabolic alkalosis. It is also used for diagnostic purposes. It is administered up to a 15 N concentration, so that, through the isotopic ammonia and urea analysis of the urine of the patient, it is possible to evaluate the hepatic function .

In the Greek patent no. 1003980 and in Greek patent application no. 2002100405, the present inventor describes the mechanism by which NH ₄ Cl decreases the levels of bilirubin in patients with severe hepatic malfunctions and hepatic encephalopathy, which is caused by the increase of the bilirubin levels. These levels may be decreased by treatment with NH ₄ Cl. The treatment of liver malignant neoplasms is also described. NH ₄ Cl salt is administered at a dosage of 600 mg/kg daily. No evidence of activity in human subjects is reported.

While working on an experimental study on Quinster rats which suffered from acute hepatitis caused with the known method of TAA administration, the present inventor found that the histological samples of the liver of the rats that had been administered NH ₄ Cl had less necrosis signs than the ones of the placebo treatment. He noticed a partial or complete regeneration of the hepatic parenchyma. Furthermore, he noticed a decrease of the TNF-α (Tumor Necrosis Factor alfa) levels, while the levels of IL- 6 were increased.

The levels of hyaluronic acid in patients with high- grade hepatic damage are usually high, but they appeared decreased in the treated Quinster rats. Furthermore, additional biochemical factors appeared improved.

It has thus been surprisingly found that NH ₄ Cl, when administered in vivo, is able to stimulate the release of endogenous interferons .

This is proved in the study on Quinster rats, treated with NH ₄ Cl, where it is evident the increase of Interleukines, that are a family of endogenous modulators of immune response. Interleukin IL-6 is also known as interferon beta-2.

"In vivo" experimental data on Quinster rats

Thioacetamid (TAA) was given to adult male Quinster rats with a course of 400 mg TAA / kg B. W. every 24 hours and for 3 consecutive days. 2 hours after the 2 ^nd and 3 ^rd dose of TTA, the animals were treated per os either with ammonium chloride (300 or 600 or 900 mg / kg B. W.) or the same dose of water. The animals were sacrificed in 6 and 12 hours after the 3 ^rd treatment with TTA. TNF-α and IL-6 levels were measured in serum (ELISA test) after 12 hours post the third TAA injection and the results are reported in the following table.

(Values represent pg/dL are expressed as mean ± SD; at least 8 animals per group)

This evidence proves that endogeneous interferons

(IL-6) are increased "in vivo" after treatment with

NH ₄ Cl. Stimulation of endogenous interferons represents a substantial improvement with respect to the administration of interferons to a patient, as it is devoid of side effects that are often encountered in interferon therapy. Moreover, the effect of endogenous interferons is more prolonged over time. Finally, but not least, interferon therapy is very expensive, while the present stimulation of endogenous interferons by administration of NH ₄ Cl is cheap and safe. The present inventor also surprisingly found that the administration of NH ₄ Cl according to a particular protocol as described below to human patients affected by various forms of hepatitis virus is able to improve the patient's conditions and to drop the viral charge.

Administration of NH ₄ Cl to a human is however accompanied by some side effects that may limit its use.

The most common side effects of the NH ₄ Cl administration are metabolic oxidation, which is due to increased chlorides and the irritation of the gastric mucosa .

The first side effect is successfully overcome by the administration of a dose of from 2 to 5 gr of NH ₄ Cl for from 3 to 5 days, with an interval of 4 to 2 days, respectively, without treatment. In another embodiment 2.8 to 3.5 gr of NH ₄ Cl are administered for from 3 to 5 days, with an interval of 4 to 2 days, respectively, without treatment. In still another embodiment about 3 gr of NH ₄ Cl are administered with the same protocol reported above. In a still different embodiment, the protocol comprises 3 days of treatment with NH ₄ Cl and 4 days of wash-out. The above protocol of administration can be repeated several times until the completion of the treatment as judged by the clinician. For example, 21 cycles of treatment are performed, which complies with the natural time of regeneration of liver after a partial hepatectomy in patients. Therefore, the duration of the treatment can be from 1 to 6 months or from 3 to 4 months for patients with partial necrosis.

Clinical evidence

Patients were treated according to the above described protocol, using a dose of 3 gr/day. The clinical results are given below:

Patient A

Disease: chronic hepatitis B

Viral charge before treatment: 1.65 x 10 ⁶ IU/ml

Viral charge after 3 months of treatment

1.65 x 10 ³ IU/ml

Patient B

Disease: hepatitis C

Viral charge before treatment 1.65 x 10 ⁸ IU/ml

Viral charge after 3 months of treatment

1.65 x 10 ⁶ IU/ml

As it is shown, the present treatment with NH ₄ Cl is able of reducing the viral charge of a factor of at least 10 ² in humans. The irritation of the gastric mucosa is overcome by the enclosure of NH ₄ Cl in gastro-resistant capsules or water-soluble acid resistant envelopes.

As said above, the dosage varies between 2 and 5 gr and the dosage form is preferably for oral administration in the form of granules or microcapsules with polymer compounds for the protection of the stomach.

It is therefore an object of the present invention to provide a NH ₄ Cl dosage form to be used in the atreatment depicted above.

In general, the formulation of the invention can be prepared according to standard techniques, as the ones reported in Remington's Pharmaceutical Sciences Handbook,

M a c k P u b . C o . , N . Y . , USA, 17th edition, 1985.

In order to assure a more constant blood concentration of NH ₄ Cl after administration, the tablets, capsules or granules can be filled with a polymer or the matrix of a pharmaceutical form can be made of an excipient that slows the release of active ingredient in the gastro-intestinal lumen.

In one embodiment, gastro-resistant granules or microcapsules in a ready to use suspension may be used.

Example of a gastro-resistant retard tablet The tablet is formulated according to standard techniques and contains 500 mg of NH ₄ Cl and the following excipients : hydroxypropylmethylcellulose, polyvinylpyrrolidone, sodium croscarmellose, magnesium stearate, talc, simeticone.

Example of gastro-resistant retard tablet:

• Ammonium Chloride mg 500

• Hydroxypropylmethylcellulose mg 40

• Polyvinylpyrrolidone mg 60

• Sodium Croscarmellose mg 10

• Magnesium stearate mg 1

• Talc mg 120

• Simeticone mg 50

The tablets are coated by one or more layers, which are resistant to the gastric acids but dissolve into the intestine, and which guarantee a slow release of the active ingredient.

To assist the patient in the assumption of the drug according to the therapy protocol described above, it is also provided a dosage form housing, particularly a blister, as the one exemplary shown in figure 1. The dosage form housing 1 comprises a sheet 2 of plastic material wherein a plurality of cavities 3 are molded and protrude out of the plane of the sheet 2, while presenting a carved, open side on the opposite face thereof. The profile shape of such cavities 3, that in the figure is elliptical, can vary and will take all the forms that can usually be adopted in this kind of applications. The dimension of the cavities 3 is sufficient to accomodate one to three tablets or capsules of NH ₄ Cl formulated as said above. For example, each cavity 3 may contain three 500 mg tablets or one 1500 mg tablet of the drug, or any other dosage according to the dosage regimen indicated before.

The sheet 2, on the opposite side thereof (not shown in figure 1) , is coated by the application of an aluminium film or a film of material that can be ruptured by pressing the cavities 3 from the upper side of the sheet 2. In such a way, the openings of the cavities 3 are closed by the said film.

The sheet 2 comprises six cavities 3, arranged in three couples 4, 4', 4" of cavities 3 put side by side. Each couple 4, 4', 4" is associated with an information matter 5, 5', 5", for example by printing or in any other way, on the same surface of the sheet 2 wherein the cavities 3 are raised. The sheet 2 is large enough to present a substantial part 2' thereof without cavities 3. The said part 2' of the sheet 2 free from cavities 3 is also associated with information matter 5' ' ' , 5 ^1V , 5 ^V , 5 ^V1 that is arranged side by side similarly to the information matter associated to the couples of cavities 3.

Specifically, both the said information matter 5, 5', 5" associated to the couples 4, 4', 4" of cavities 3 and the information matter 5''', 5 ^1V , 5 ^V , 5 ^V1 associated to the part 2' of the sheet 2 that is free from cavities 3 report an indication of the days of the week, such as "day 1", "day 2" and so on or "Monday", "Wednesday" and so on or abbreviations thereof.

In such a way, only for three days a week the dosage form container 1 present cavities 3 filled with the drug, while the other days are free from drug according to the dosage regimen indicated above.

Moreover, for each day two cavities 3 are present, each containing, for example, a 1500 mg NH ₄ Cl dosage form (one or more tablets or capsules), one for a morning administration (typically before breakfast) and the other for an evening administration (typically before dinner) .

In another embodiment, the said information matter

5''', 5 ^1V , 5 ^V , 5 ^V1 associated to the part 2' of the sheet 2 that is free from cavities 3 is arranged on a strip 6 that can be torn off on the day of break of the treatment reported in the information matter.

In another embodiment, the sheet 2 may present seven couples of cavities 3, one for each day of a week, but only three couples will include the wanted dosage form, the other four couples of cavities 3 being empty. Instead of these latter four couples of cavities, only four single cavities may also be foreseen. These empty cavities are also designed to be pressed on the day of break of the treatment reported in the information matter .

According to what has been said above, it is provided a method of treating or preventing a viral infection, hepatic failure, hepatic necrosis and other conditions caused by toxic agents or by autoimmune reaction or a tumor that is susceptible of treatment with interferons alfa, beta or gamma, the said method comprising administering a therapeutically effective amount of NH ₄ Cl dosage form to a patient in need thereof.

In one embodiment, the viral infections will be those infections susceptible to the treatment with interferons alfa, beta or gamma. In one embodiment the said viral infections are hepatitis B, hepatitis D, hepatitis C or chronic hepatitis C, D or B, or complicated Eipstein-Barr virus infection. In one embodiment, conditions that can be treated according to the invention are selected from autoimmune hepatitis, non-alcoholic steatohepatitis, sclerosant cholangitis, multiple sclerosis, Wilson's disease and liver carcinoma.

In one embodiment, the said toxic agents are selected from abuse of alcohol or drugs and chemical hepatotoxic agents that may lead to hepatic necrosis, such as the poison of certain mushrooms (for example, Amanita falloides) .

In one embodiment, the tumors susceptible to the treatment with interferons are selected from cancer of the kidney, malignant melanoma, carcinoid tumors, lymphoma and leukaemia.

The treatment of the invention can also be associated with exogeneously administered interferons or antiviral agents.