Cross-Reference to Related Applications This is a continuation-in-part of my copending patent applications Serial Nos. 577,204 and 577,295 both filed September 4, 1990, to which priority is claimed.

Field of the Invention This invention relates to the treatment of infectious diseases in mammals by inactivation of microbes in or bound to blood cells or other body cells or tissues. Background of the Invention

The term "physiologically compatible iodide" is used to describe a compound which disassociates in aqueous solution to produce iodide ions and which is non-toxic or has low toxicity when introduced into the blood stream of humans and other mammals. Potassium iodide and sodium iodide are considered to be the optimum iodides suitable for use in this invention.

The present invention provides a method for treating those diseases which result from microorganisms which are resistant to standard therapy or for which there is no known treatment.

A major function of red blood cells is to transport oxygen to the organs and tissues of the body. Oxygen is transported by the reversible oxygenation-deoxygenation of hemoglobin. Under normal conditions, hemoglobin in red blood cells is fully saturated with oxygen as the blood leaves the mammals lungs. Such oxygen is not present in a form which is reactive with other constituents of the red blood cell. Many microorganisms which can cause disease in man and other mammals may enter into blood cells where they are unaffected by drugs in the blood stream. It would be desirable to provide a method for introducing an antimicrobial compound into blood cells to attack the pathogenic microbes. This result cannot be accomplished to an effective degree using known antimicrobial compounds either because such compounds do not readily enter into blood cells or must be present in toxic amounts in the

blood stream to effect significant entry into blood cells. It is to a solution to this problem that the present invention is addressed.

Certain parasites (e.g., Malaria, trypanosomas), bacteria (Bartonella) and viruses may be carried in blood cells and in other cells and tissues. Recently the bacteria Yersinia enterocolitic has become a serious contaminant of blood.

Protozoa give rise to many diseases, some of great medical and economic importance. Examples of such protozoa are the genus Plasmodium, e.g. P. falcipanim, P. malaήae, P. ovale and P. vivax, which causes malaria, Trypanosoma, which causes Chagas' disease, and Leishmania, which cause a variety of leishmaniasis. The method of this invention is expected to be effective in treating such diseases.

The use of elemental iodine as an antiseptic dates back to 1839. It is used today for various medicinal purposes. The combination of iodine with various solubilizing polymers led to a class of new compositions known as iodophors, which dominate the market once satisfied by simple alcoholic or aqueous iodine solutions. Iodine complexes with nonionic surfactants, eg, polyethylene glycol mono(nonylphenyl) ether, or polymers, e.g., poly(vinylpyrrolidone) (PVP) and dextrans. The complexes function by rapidly liberating free iodine in water solutions. They exhibit good activity against bacteria, molds, yeasts, protozoa, and many viruses. Most organisms are killed within 15 to 30 seconds of contact. These iodophors are generally nontoxic, nonirritating, non-sensitizing, and noncorrosive to most metals (except silver and iron alloys). Medicinal povidone-iodine preparations include aerosol sprays, gauze pads, lubricating gels, creams, solutions, douche preparations, suppositories, gargles, perineal wash solutions, shampoos, and skin cleansers and scrubs. Povidone-iodine preparation are applied topically to the skin and to membranes, e.g. vaginal membranes, and to infected wounds and surgical incisions. The uses continue to be largely medicinal, though some iodophors are used in industrial sanitation and disinfection in hospitals, building

maintenance, and food-processing operations. There has been some interest in the use of iodine for purification of potable water and swimming pools. Two other iodine-containing compounds, p-tolyldiiodom ethyl sulfone and p-chlorophenyldiiodomethyl sulfone have been recommended as preservatives.

Iodine and iodine-containing compounds and preparations are employed extensively in medicine, eg, as antiseptics, as drugs administered in different combinations in the prophylaxis and treatment of certain diseases, and as therapeutic agents in various thyroid dyscrasias and other abnormalities. Iodine is a highly reactive substance combining with proteins partly by chemical reaction and partly by adsorption. Therefore its antimicrobial action is subject to substantial impairment in the presence of organic matter such as serum, blood, urine, milk, etc. However, where there is no such interference, non-selective microbicidal action is intense and rapid. A saturated aqueous solution of iodine exhibits anti-bacterial properties.

However, owing to the low solubility of iodine in water (33 mg/100 ml at 25°C), reaction with bacteria or with extraneous organic matter rapidly depletes the solution of its active content. Iodide ion is often added to increase solubility of iodine in water. This increase takes place by the formation of triiodide, I ₂ + I ^" = I ₃ ^" . An aqueous solution of iodine and iodide at a Ph of less than eight contains mainly free diatomic iodine I, and the triiodide I ₃ ^" . The ratio of I ₂ and I ₃ depends upon the concentration of iodide.

Although iodine is less likely to be consumed by proteinaceous substrates than bromine and chlorine, its efficacy as a disinfectant is still reduced at certain antiseptic applications. This is due to a reducing effect of the material to be disinfected which leads to the conversion of iodine into non-bactericidal iodide. Thus, not only the reservoir of available iodine is diminished but also the equilibrium of triiodide is influenced as well. Both of these effects cause a decrease in the proportion of free molecular iodine, the actual anti-microbial agent. When povidone-iodine preparations are

contaminated with liquid substrata (e.g. blood, etc.) there is, in addition, the dilution effect characteristic of povidone-iodine systems which causes an increase in the equilibrium concentration of free molecular iodine. To what extent the latter effect compensates for the other two effects depends on the content of reducing substances. Thus with whole blood, a strong decrease of the concentration of free molecular iodine occurs, while, in the presence of plasma, it remains practically unchanged. Durmaz, et al, Mikrobiyol. Bui. 22 (3), 1988 (abstract); Gottardi W, Hyg. Med. 12 (4). 1987. 150-154. Nutrient broth and plasma had little inactivating activity but 1 g hemoglobin inactivated 50 mg of free I; experiments with ^l25 I showed that uptake of I by

[human] red cells occurred rapidly. Optimal antimicrobial effects in clinical use should be achieved in relatively blood-free situations. Povidone iodine produced a potent and sometimes persistent bactericidal effect towards bacteria on healthy skin. Lacey, R. W. J Appl Bacteriol 46 (3). 1979. 443-450. The bactericidal activity of dilute povidone-iodine solutions is inversely proportional to the concentration of the povidone-iodine solutions and is inhibited to the greatest extent by blood, followed by pus, fat and glove powder. Zamora J L; Surgery (St Louis) 98 (1). 1985. 25-29: Zamora, Am. J. Surgery, 151, p. 400 (1986); see also, Waheed Sheikh, Current Therapeutic Research 40, No. 6, 1096 (1986). Van Den Broek, et al, Antimicrobial Agents and Chemotherapy, 1982, 593-597, suggests that povidone-iodine is bound to cell wall proteins leaving little for interaction with microorganisms in the liquid phase (See, also, Abdullah, et al., Arzneim.-Forsch./Drug Res. 31 (I), Nr. 5, 828). Ninneman et al, J. of Immunol. 81, 1265 (1981) reported that povidone-iodine was absorbed in serum albumin and it is know that- povidone-iodine is bound to albumin but it has been discovered that the antibiotic activity of povidone-iodine is not destroyed by albumin binding. Whether the activity remains because the albumin povidone-iodine is active or whether povidone-iodine and/or I, are released from the albumin- povidone-iodine complex is not known.

Summary of the Invention

This invention relates to the treatment of diseases resulting from pathogenic microbes which may be carried in the blood and enter or bind to blood cells. According to the method of this invention, a physiologically compatible iodide compound, such as potassium iodide or sodium iodide (or mixtures thereof), is introduced into the blood stream of the mammal to be treated after which an oxidizing amount of molecular oxygen or peroxide oxygen are introduced to convert the iodide to iodine.

Specifically, the present invention is a method of treating an mammal suspected or known to have a disease caused by a microorganism which is carried by the blood and which can enter blood cells comprising introducing a physiologically effective amount of a physiologically compatible iodide compound of from 0.001 to 0.1 percent, by weight, into the blood stream of the mammal to be treated and thereafter introducing an molecular oxygen or peroxide oxygen into the blood stream of said mammal in an amount to convert iodide to iodine in an antimicrobially effective amount in blood cells.

Description of the Preferred Embodiments The first step in carrying out the present invention is to introduce a physiologically compatible iodide compound, such as potassium iodide or sodium iodide (or mixtures thereof), into the blood stream of the mammal to be treated. The second step of the method is to introduce an oxidizing amount of molecular oxygen or peroxide oxygen into the blood stream to convert the iodide to iodine.

Sodium and potassium iodides are well tolerated by the body and the iodide ion enters freely into cells in the blood through the cell membranes. Iodides per se have little or no antimicrobial activity, however, and a further step is necessary to generate in situ in the cell iodine which is a very potent antimicrobial composition.

After the iodide has been introduced into the blood stream, an oxygen compound which is capable of oxidizing iodide ion to iodine is introduced. The oxygen compound may be molecular oxygen introduced by subjecting the mammal to hyperbaric pressure or to an enhanced oxygen atmosphere, e.g.

pure oxygen or oxygen diluted with air. The oxygen compound may also be in the form of a peroxide, e.g. hydrogen peroxide. Povidone-hydrogen peroxide is a known complex and is commercially available from GAF Corporation, see, e.g. Tableting with Povidone ³ A povidone USP (1981) and PVP Polyvinylpynolidone (1982).

Iodide in the liquid phase of the blood and in the cells in the blood when converted to iodine will become an effective antimicrobial agent to inactivate pathogenic microbes in the blood and in blood cells.

Concentrations of from 0.001 percent to 0.1 percent, by weight in the blood stream, of iodide and comparable concentrations of povidone-hydrogen peroxide are considered to be effective. Maximum tolerable concentrations have not been determined, however, and care must be taken not to exceed the tolerance of a particular patient.

The method as described may be carried out repeatedly until the blood is free of pathogenic organisms. The method may also be carried out using increasing concentrations of reagents as the tolerance level of the patent is determined, using very low concentrations initially and increasing the concentrations according to the patient's reaction.

Serum or plasma losses all pigment and becomes water clear after H,0 ₂ is added to regenerate I ₂ . In one example, plasma removed from whole blood which had been treated with variable amounts of PVP (MW approx. 30,000 + MW approx. 90,000) + 0.5% PVP-I and held at ambient for 7 days and failed to give a starch reaction were treated with a small amount of commercial H ₂ 0, liquid (3% cone.) or H,0 combined in PVP as a binding agent. Both materials caused the slightly yellowish plasma to turn deep orange. When left standing at ambient from 4 hours to overnight the color gradually disappeared and the plasma become virtually water clear. This implies that plasma pigments (bilirubin, etc.,) are oxidized colorless. Of special interest is that the PVP-H ₂ 0, generates bubbles and foam in the plasma for at lest 5 hours indicating that H,0 ₂ added to PVP is firmly bound and stabilized to a slow-release complex.

A very slight amount of H,0, added will cause the RBC's to become very red. Concentrations of from 0.1% to 0.01% H ₂ 0, were studied. As little as 0.025% oxygenated the red cells. When PVP is present in the blood the red color is reduced proportionally to PVP concentration. If too much H ₂ 0 ₂ is used by itself or as PVP-H ₂ 0 ₂ the blood remains very viscous as if gelatin has occurred.

In another experiment a stock solution of C15 (MW approx. 15,000) PVP in a concentration of 0.5% PVP-I) was added to plasma. The addition of 3% PVP solution resulted in a very, very slight orange color. Additions of 6%, 9%, 12% and 15% PVP solution resulted in an increasingly intense yellow color. When tested with starch there is no detectible I ₂ in the solutions having from 6%— 15% addition, indicating that the color changes represent only the concentration of the PVP C-15. A sample of the plasma with 15% PVP added, was treated with 4 day old PVP-H ₂ 0 ₂ . There was a gradual conversion of the PVP-iodide to iodine.

A sample of supernatant of red blood cells that was slightly pink with hemoglobin was treated with 0.1% Nal + a trace H,0, This solution gave a negative starch test indicating the presence of a trace amount of hemoglobin with iodide bound to it. The addition of a few drops of 3% H ₂ 0 ₂ resulted in a distinct though slight I, color. As little as 0.1% Nal was sufficient to saturate all hemoglobin. This iodine-hemoglobin complex can then be oxidized back to I,.

Supernatant from blood treated with 0.5% PVP-I only after 3 days storage shows yellow color with H ₂ 0 ₂ suggesting that Hb is fully saturated by 0.5% PVP-I with only a small amount of iodide left over in supernatant.

When Nal is added to blood or packed RBC's, the red cells turn much redder and then darker again as the supernatant takes on a slight yellow pink-brown color. Some of the iodide evidently was converted to I ₂ , perhaps by the oxyhemoglobin, liberating small amounts of I ₂ . Always iodide treated cells were slightly more red than cells in a saline control.

A solution of Nal, when treated with H ₂ 0 ₂ , will turn yellow but only

to a modest degree regardless of the concentration of Nal. However if PVP is present the color gradually deepens to a true I ₂ color. Presumably the PVP pulls the I-H ₂ 0 ₂ molecules closer together for greater reactivity.

The ability to kill virus, VSV, was tested. VSV (approx. 8-9 logs) was inoculated into 2 day old whole blood with plasma removed (concentrated

Table I WHOLE BLOOD CONDITIONS LOG KILL

0.5% PVP-I + 6% PVP C30 + 1% HES LMW ¹ 5.00 0.5% PVP-I + 6% PVP C30 + 0.1% HES LMW 4.33 0.5% PVP-I + 6% PVP C30 + 1% HES HMW 5.67 0.5% PVP-I + 6% PVP C30 + 0.1% HES HMW 4.33

0.5% PVP-I + 3 PVP K26/32 4.33 0.5% PVP-I + 6% PVP K26/32 4.17 0.5% PVP-I + 3% PVP K90 4.33 0.5% PVP-I + 6% PVP K90 6.00 0.5% PVP-I + 3% PVP K120 5.00 0.5% PVP-I + 6% PVP K120 6.00 0.5% PVP-I + 3% PVP C30 4.33 0.5% PVP-I + 6% PVP C30 5.33

0.5% PVP-I + 3% PVP C30 + 0.1% H,0 ₂ 5.67

0.5% PVP-I + 6% PVP C30 + 0.1% H, ^" θ ₂ 8.67

3% PVP C30 + 0.1% H,0, 0.67

6% PVP C30 + 0.1% H ₂ 0 ₂ 2.33

0.5% PVP-I + 0.1% H,0, 5.33

0.1% HA 0.67

0.5% PVP-I 2.17

0.1% Nal + 0.1% H,0, 5.00 0.1% Nal + 0.05% H,0, 2.67 0.1% Nal + 0.025% H,5 ₉ 3.17 0.1% Nal + 0.001% H, ^" θό 3.17

POSITIVE CONTROL (8.67 LOGS QUANTITATED)

HES = Hydroxyethyl Starch; LMW = Low Molecular Weight; HMW

= High Molecular Weight. Added for osmotic balance. MgS0 ₄ or NaS0 ₄ may also be used.

The method just described can be adapted for in vitro treatment of cell-containing fluids wherein it is desired to inactivate microbes in the cells. In this embodiment, the invention comprises a method of treating an cell- containing composition which is suspected or known to contain a microorganism which can enter cells. The method comprises the steps of (a)

introducing an effective amount of a physiologically compatible iodide compound of from 0.001 to 0.1 percent, by weight, into the cell-containing composition to be treated, and thereafter introducing an molecular oxygen or peroxide oxygen into the composition in an amount to convert iodide to iodine in an antimicrobially effective amount in blood cells. In the in vitro embodiment of the invention, it is particularly desirable to add the oxygen as povidone-hydrogen peroxide and to provide additional povidone, or other osmotic pressure balancing salts or polymers. Suitable substances for being included in the cell containing preparation to provide an osmotic balance between the interior and the exterior of the cells; i.e. to prevent undue dehydration or swelling of the cells as a result of a differential in osmotic pressure between the interior of the cells and the liquid surrounding the cells. Povidone, it is believed, performs this function directly, i.e. in effecting the osmotic pressure by concentration, and by "sealing" the red blood cell surface membrane and thus reducing the rate of flow through the membrane.

Calcium or magnesium salts, sulfate salts, and/or water soluble polymers, e.g. hydroxyethyl starch, for example, may be used in cell containing solutions. Upon entry into the cell the iodide ion changes the osmotic balance between the interior and exterior of the cell. Addition of molecules which are too large to enter into the cell, but increase the effective concentration of the fluid outside the cell may be used to restore the proper osmotic balance.

Industrial Application This invention is useful in veterinary medicine and in human therapy and in the treatment of cell-containing compositions generally.