Title:  Treatment of herpes infection with composition containing quaternary ammonium compound and an anti-viral agent

United States Patent:  6,284,289

Assignee:  Bio Pharma Sciences B.V. (NL)

Filed:  November 5, 1997

PCT NO:  PCT/NL96/00038

102(e) Date:  November 5, 1997

PCT PUB. Date:  August 15, 1996

Foreign Application Priority Data:  Feb 06, 1995[NL] (9500216)

A pharmaceutical composition and method for the treatment of herpes simplex infections is disclosed. The composition contains a quaternary ammonium compound such as cetrimide or benzalkonium chloride and an antiviral agent such as acyclovir, bromoinyldesoxuridine, 3-fluorothymidine, idoxuridine, propyl gallate, proanthocyanides or glucosamine. The compound can also contain a plant extract such as camomile.

Description of the Invention

The present invention relates to a pharmaceutical composition for the treatment of herpes.

Herpes simplex infection on the skin causes superficial painful spots and blisters, which eventually open, thereby causing lesions. Herpes is mainly caused by Herpes simplex virus (HSV) type 1, but can also be the result of HSV type 2 which usually causes genital herpes. Conversely, genital herpes is caused in about 30% of cases by HSV 1.

Infections of the mouth are designated with the term herpes labialis, also called cold sore (feverblister). Other parts of the face, such as eyes and nose, can also be affected. This is then referred to as facial herpes simplex. The infection can also manifest itself on other parts of the body.

About 70-90% of the population is primarily infected with HSV. These people are then carriers of the virus. Once an individual has been infected with the HSV, this virus will thereafter remain latently present in the body. In latent state the virus is situated in nerve cell bodies in the ganglia. Due to particular stimuli, such as influenza infection or other respiratory disorders, gastro-intestinal infections, stress, fatigue, menstruation, pregnancy, allergy, sunlight and fever, the latent virus can be activated. It will travel from the ganglia along well-defined nerve paths to the skin surface and there multiply and cause the symptoms. This recurrent form of herpes occurs in about 40% of the infected individuals.

A per se reasonably innocuous herpes simplex infection can lead to much more serious infections, such as keratitis and encephalitis. It is therefore important that the virus niduses, at the location of the infection, are efficiently destroyed.

At the moment the most frequently used remedy against HSV infections is acyclovir, which is sold for instance under the brand name Zovirax. Acyclovir is a guanine analog which interferes with the DNA polymerase of the virus and thereby inhibits viral DNA replication. The virus is prevented from multiplying but the virus itself is however not killed. The virus can therefore withdraw to the ganglia, thus resulting once again in latency.

Transmission of HSV-1 occurs through direct contact via saliva or the infected spot on the skin. This transmission is also not prevented by acyclovir.

Another problem is the occurrence of secondary bacterial infections, for instance impetigo, caused by staphylococci and/or streptococci.

On account of these problems of herpes infection, which may or may not be attendant, there is an obvious need for a pharmaceutical preparation which can diminish or even prevent the occurrence of latency as well as the transmission and secondary bacterial infections.

According to the present invention it has now been found that a pharmaceutical composition consisting of a quaternary ammonium compound as a first component and/or an antiviral agent as a second component and/or a plant extract as a third component, wherein the three components are mutually compatible, in a pharmaceutically acceptable base, can resolve the above stated problems.

In order to break the vicious circle of latency, recurrence and renewed latency of the virus, it is necessary to kill the virus itself. Less or even no latency can hereby reoccur in the case of primary or recurrent infection since the dead virus cannot withdraw into the ganglia. The most important component of the present composition according to the invention is therefore a virucidal substance whereby the virus is killed.

Antiviral agents can be subdivided into a number of categories (Colgate, S. M. & Molyneux, R. J., Bio-active natural products, 410, CRC Press, Inc. (1993)), designated with the classification group Ia to group Vb. According to the invention it has now been found that, in order to deal with HSV infections to the fullest possible extent, preferably one or more substances from group IVb must be combined with one or more substances from group Va. Substances from group IVb exhibit virucidal activity, while compounds from group Va display virustatic and antiviral activity. By the combination of both types of substance the virus replication is inhibited and in addition the viruses already present are killed.

In order to ensure that the secondary infection of the lesion caused by HSV infection by other micro-organisms such as bacteria is prevented, it is recommended that either the first component and/or the second component has disinfecting properties.

In order to alleviate the associated symptoms of pain and inflammation a plant extract is preferably also used. This extract preferably also has a soothing effect in addition to inflammation-inhibiting properties.

Products from group IVb which also have a disinfecting activity and can therefore be used in the pharmaceutical composition according to the invention can be selected in a manner known to the skilled person. Use is herein made of the end point titration technique (EPTT) as described by Colgate & Molyneux (supra. p. 413), with which the virucidal activity of a product can be tested. The activity is expressed in virus titre reduction which is determined in vitro by incubation of a herpes virus suspension with dilutions of the product for testing at 37^oC. for 5 minutes. A good product will give a minimal titre reduction of 10³.

From a general screening of known disinfectants for their virucidal action against Herpes simplex type 1 and Herpes simplex type 2 strains (clinical isolates) it has been found according to the invention that a few products display very high activity, even at 25^oC. This is very advantageous because the temperature on the skin is generally lower than 37^oC. and even lower than 34^oC. It has been found that the quaternary ammonium compounds cetrimide and benzalkonium chloride in a concentration of 50-200 .mu.g/ml and 100-200 .mu.g/ml respectively showed a titre reduction of at least 10³ for a test period of 5 minutes at 25^oC. Other known disinfectants, such as alcohols, phenols, peroxides, biguanides, aldehydes, chlorine compounds etc. displayed an activity which was a minimum of five times lower. Only mercury compounds and determined heavy metal compounds have a better activity. However, due to their high toxicity these compounds are not suitable for the intended application.

Quaternary ammonium compounds are well soluble in water and alcohol but cannot be combined with any random other product. An important requirement for the second component is therefore that it must be compatible with the first component. Anionic products, soaps, nitrates, heavy metals, oxidizing products, rubber, proteins and the like are not compatible with quaternary ammonium compounds. Such products are therefore not suitable for use in the composition according to the invention. The second component is preferably not teratogenic and can be given in a high dosage without being toxic therein. In preference the second component further shows a good penetration of the skin.

As second component known antiviral products can be used, such as acyclovir, BVDU, 3FT, Idoxuridine etc., as long as they are compatible with the first component. In addition non-toxic natural products with antiviral activity can be used.

The suitability of the second component can likewise be tested with a per se known EPTT method (Colgate & Molyneux, supra, p. 414). Use is herein made of VERO cells. According to the invention it has thus been found that gallates have a good antiviral activity in vitro. Propyl gallate in a concentration of 100 .mu.g/ml thus has a titre reduction factor of 10⁴. In a concentration of 25 .mu.g/ml the reduction factor of the infectious particles in VERO cells is 10³. Ethyl gallate has a reduction factor of 10⁴ in a concentration of 100 .mu.g/ml and of 10² at 25 .mu.g/ml. Ethyl gallate is therefore slightly less active.

The compatibility of the first component and the second component can be determined by testing a mixture of the two components on HSV-1. It has been found that a mixture of propyl gallate and cetrimide (2:1) in a concentration of 250 .mu.g propyl gallate to 125 .mu.g cetrimide still has a virucidal action of 10³ after a test period of 5 minutes at 25^oC. The same applies in the case of ethyl gallate and cetrimide. A mixture of cetrimide and BVDU or acyclovir continues to display an antiviral activity after dilution in vitro to 5 .mu.g/ml BVDU or. acyclovir and 0.1 .mu.g/ml cetrimide.

The pharmaceutical composition preferably also contains a plant extract, with which the pain and effects of the inflammation reaction can be alleviated. Here it is also the case that the extract may not interfere with the activity of the first and the second component.

For this purpose various plant extracts were tested with cetrimide and propyl gallate or benzalkonium chloride and propyl gallate to see whether the virucidal activity is maintained and the components are compatible. It has been found that extracts of camomile and Calendula remain useable in vitro. Extracts of Aloe vera, Echinaceae root, tricolor violet, Senna, Melissa and/or hawthorn are also capable of alleviating the inflammation reaction or pain while the virucidal activity is retained.

Particular plant extracts however cause a marked reduction in the virucidal activity of some quaternary ammonium compounds. It has for instance been found that 10% hamamelis completely deactivates the virucidal and antibacterial activity of benzalkonium chloride (0.5%). The activity of 0.1% benzalkonium chloride against herpes and bacteria is reduced 4 to 8 times by sage and great burdock extract. However, a combination of cetrimide with a second component and a plant extract of camomile, Calendula, sage, great burdock and senna was found in vitro to remain active against Herpes simplex virus as well as bacteria.

The compatibility of the plant extract to be used must therefore be determined beforehand. Such a determination lies within the reach of the average skilled person.

Suitable plant extracts come for instance from Aesculus hippocastanum L; Aloe vera L; Anagallis arvensis L; Anthemis nobilis L; Arctium lappa L; Aristolochia clematitis L; Arnica montana L; Betonica officinalis L; Calendula officinalis L; Capsicum annuum (tetragonum); Carica papaya L; Carlina acaulis L; Caryophyllus aromaticus L; Cynoalossum officinale L; Echinacea anaustifolia; Echinacea purpurea L; Eupatorium cannabinum L; Geranium robertianum; Geum urbanum L; Glechoma hederacea L; Hamamelis virginiana L; Hypericum perforatum L; Inula helenium L; Jualans regia L; Juniperus oxycedrus L; Lavandula officinalis; Lawsonia alba L; Lysimachia nummeralia L; Lythrum salicaria L; Malva sylvestris; Marrubium vulgare L; Matricaria chamomilla L; Mentha piperita L; Myroxylon balsamum L; Myrtus communis L; Olea europaea L; Prunus amyadalus; Pyrus cydonia L; Quercus robur L; Quillaja saponaria; Rubus idaeus L; Salvia officinalis L; Saponaria officinalis L; Smilax officinalis; Solanum dulcamara L; Solidago virga aurea L; Styrax tonkinensis; Styrax benzoides; Styrax benzoin; Symphytum officinale L; Trigonella foenum-graecum L; Tropaeolum majus L; Urtica urens L; Urtica dioica L; Viola tricolor L.

The pharmaceutical composition according to the invention, which consists of a combination of one or more quaternary ammonium compounds with a virucidal and antiseptic activity and/or an antiviral product which is compatible with the quaternary ammonium compound and inhibits the virus replication, and/or a plant extract which is likewise compatible with both above mentioned products and alleviates the associated effects of the herpes infection such as pain, itching, swelling, tingling etc., provides a total treatment of herpes infection. The virucidal activity of the composition kills the viruses, whereby latency will occur less or not at all. The antiviral activity inhibits the virus replication and therewith the multiplying of the virus. The antiseptic activity prevents secondary bacterial infections. Finally, the inflammation-inhibiting activity prevents inflammation and moreover soothes the pain and the itching.

The components of the composition according to the invention are preferably included in a pharmaceutically acceptable base. For the base also applies that it may not reduce the activity of the three components. In order to test whether a base is suitable, the virucidal activity of the first component and the disinfecting activity can be determined. The disinfecting activity is for instance determined in a manner lying within reach of the skilled person for a period of 5 minutes at 25^oC. on Gram-negative germs, for instance of Pseudomonas aeruainosa or Escherichia coli.

Examples of suitable bases are polyethylene glycols in different molecular sizes or mixtures thereof, esters of fatty acids or mixtures thereof, whether or not mixed with emulsifying and/or skin-care constituents. Also suitable are mixtures of polyethylene glycols and/or esters of fatty acids with or without the emulsifying and/or skin-care constituents.

The pharmaceutical composition according to the invention can take the form of a powder, suspension, solution, spray, emulsion, unguent or cream and can be used for localized application. Such composition can be prepared by combining (i.e. mixing, dissolving etc.) the active components in the form of a free acid or salt with pharmaceutically acceptable excipients of a neutral character (such as aqueous or non-aqueous solvents, stabilizers, emulsifiers, detergents, additives) and in addition, where necessary, colorants, aromatic substances and/or flavourings. The concentration of the active ingredient(s) in a pharmaceutical composition can vary between 0.001% and 100% (w/v), depending on the nature of the treatment and the manner of application. An unguent is recommended.

The composition of the invention contains for instance 10-90% of a non-aqueous base, 1-20% of an alcohol, 0.1-5% of one or more quaternary ammonium compounds, and/or 0.01-2% of one or more Antiviral agents, and/or 0.5-10% of one or more plant extracts. The quantity of plant extract used is closely related to the activity thereof and to the concentration of active constituents in the extract.

A preferred composition according to the invention contains 20-60%, preferably 52% PEG 400, 10-40%, preferably 26% PEG 4000, 2-20%, preferably 9% glycerol, 0.5-1.8%, preferably 1% cetrimide, 0.2-3%, preferably 1% cetyl alcohol, 5-15%, preferably 8% camomile extract and 0.2-1%, preferably 0.25% propyl gallate.

Claim 1 of 10 Claims

What is claimed is:

1. A pharmaceutical composition for the treatment of herpes simplex infections, comprising a quaternary ammonium compound in a concentration effective to exhibit virucidal activity against herpes simplex virus, an antiviral agent and a pharmaceutically acceptable base, wherein the quaternary ammonium compound is present in a range from about 0.1% to about 5% and is selected from the group consisting of cetrimide and a benzalkonium compound; and the antiviral agent is present in a range from about 0.01% to about 3% and is selected from the group consisting of an acyclovir, bromylvinyldesoxuridine, 3-fluorothymidine, idoxuridine, propyl gallate, ethyl gallate, proanthocyanides and glucosamine, wherein the quaternary ammonium compound and the antiviral agent are mutually compatible.

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