WO2001001975A2 - Hypoestoxides, derivatives and agonists thereof for use as antiparasitic agents - Google Patents

Abstract

Novel enhanced usage of hypoestoxides derivatives and agonists thereof as active agents against nucleated infectious entities including known parasites and the like microbiological insultors of living tissue, systems and organisms, known modes of administration and related compounds are used alone or in combination with the instant teachings.

Description

HYPOESTOXIDES, DERIVATIVES AND AGONISTS THEREOF FOR USE AS

ANTIPARASITIC AGENTS

BACKGROUND OF THE INVENTION

1. Cross Reference to Related Applications

Expressly incorporated herein by reference are U.S. Letters Patent No. 5,801,193,

and co-pending applications, U.S. Serial Nos. 09/006,946; 09/007,308; 09/298,653; and

PCT WO 98/46222.

2. Field of the Invention

This invention relates to the use of diterpene compounds, in particular

hypoestoxides, derivatives and agonists thereof for anti-parasitic therapy and prophylaxis,

wherein unexpected and beneficial results have been, noted against nucleated infectious

agents, among other things.

3. Background Art

Almost a third of the world's population lives in areas at risk of malaria, and

according to estimates by World Health Organization (WHO), one to two million children

in Sub-Saharan Africa die from the disease each year (WHO, Wkly Epidemiol Rec. 1997;

72: 269-76). This long-standing problem has not been addressed by conventional

disclosures and remains a pressing issue in most of the developing nations of the world, in

addition to demanding instant clinical study.

Malaria is caused by the protozoan parasites Plasmodium falciparum, P. vivax, P.

ovale and P. malariae in humans and by P. berghei, P. chabaudi, P. yoelii, P. vinckei in

rodents; P. knowlesi, P. cynomolgi in primates and P. Iophurae in avian. Malaria is the

most deadly protozoan infection of humans. Hundreds of millions of cases of malaria

occur annually and infections with P. falciparum the most virulent human malaria parasite, leads to millions of deaths each year (Walsh J.A. Annals of the New York Acad. Sciences

1989; 569: 1-16). Despite extensive control efforts, the incidence of malaria is not

decreasing in most endemic areas of the world, and in some areas, it is clearly increasing

(Oaks et al, eds. 1991 : Washington, D.C.: National Academy Press). A major reason for

the persistence of the severe malaria problem is the increasing resistance of parasites to

available chemotherapeutic agents. Resistance to chloroquine, the most widely used

antimalarial in the last 50 years, is now very common, and other available antimalarials are

limited by resistance, high cost and toxicity (Olliaro et al; JMA 1996, 275:230-233).

Other antimalarials such as atrabrine dihydrochloride (quinacrine hydrochloride)

produces a number of undesirable side effects, such as jaundice and gastrointestinal

disturbances (Bogitsh, B.J. and Chen, T.C. eds. Human Parasitology, 2nd edition,

1998: Academic Press, San Diego, London, Boston, New York, etc.). Thus, the

development of antimalarial drugs must be a continuous process, and requires both

theoretical and clinical attention urgently.

SUMMARY OF THE INVENTION

To provide a solution to this longstanding need an unexpected use of the instant

compounds has generated the teaching of the present invention, which overcome the

drawbacks of the prior art.

Applicants' invention rests on their finding that a select group of hypoestoxide

analogs possess unexpected prophylactic and therapeutic effectiveness as growth

inhibiting agents against harmful organisms including the known protozoan parasite of the

genus, Plasmodium, among others having similar status as nucleated infectious agents. In particular, the present invention comprises a method for inhibiting and/or

delaying the growth of these parasites in subjects. The method comprises administering to

a subject in need of antiparasitic therapy or prophylaxis, a pharmaceutical composition

comprising a therapeutically effective amount of a compound of the formula.

In another aspect, the invention provides a method of treating a subject to alleviate

pathological effects of the growth of parasites of numerous other members of the

Protozoan family and related microorganisms (e.g. Plasmodia, Trypanosoma, Theileria,

Babesia and Coccidiά).

According to a feature of the present invention there is provided a therapeutic

method for treating a subject having a disease caused by infection with a protozoan

parasite, comprising inhibiting the growth of said parasite by administering to said subject

an effective amount of at least one compound, or a pharmaceutically acceptable prodrug of

said compound, said compound having the structural formula I:

where

b) P(O)(OH)₂,

c) P(O)(OH)(OM), wherein M is an alkali metal salt, or an alkaline earth metal

salt, d) P(O)OM₂ wherein M is each independently selected from the group consisting

of alkali metal salts and alkaline earth metal salts,

e) Alkyl of 1 to 12 carbon atoms substituted or unsubstituted, straight chain or

branched, 0 to 6 double bonds, (CH₂)_n morpholine where n = 1-4,

morpholinomethylphenyl, ortho-aminophenyl, ortho-hydroxyphenyl,

(CH₂)_nCOOR₂ where n = 1-4;

wherein R₂ is H, an alkali metal salt, an alkaline earth metal salt,

NH₄ ⁺, N⁺(R₃)₄ wherein R₃ is each independently selected from the group consisting

of H and alkyl of 1 to 4 carbon atoms,

f) COR, wherein R, is selected from the group consisting of H, (CH₂)_nCH₃

wherein n = 0-6, (CH₂)_nCOOR₂ wherein n = 1-4 and R2 is as previously

defined, and (CH₂)_n N+(R₃)₃, wherein n = 1-4,

wherein the effective amount is sufficient to ameliorate at least one symptom of

said disease.

Likewise, according to a further feature of the present invention there is provided a

prophylactic method for protecting a subject in danger of contracting disease caused by

infection with a protozoan parasite, comprising inhibiting the growth of said parasite by

administering to said subject an effective amount of at least one compound, or pharmaceutically acceptable prodrug of said compound, said compound having the

c) P(O)(OH)(OM), wherein M is an alkali metal salt, or an alkaline earth metal

salt,

d) P(O)OM₂ wherein M is each independently selected from the group consisting

of alkali metal salts and alkaline earth metal salts,

e) alkyl of 1 to 12 carbon atoms substituted or unsubstituted, straight chain or

branched, 0 to 6 double bonds, (CH₂)_n morpholine where n = 1 -4,

morpholinomethylphenyl, ortho-aminophenyl, ortho-hydroxyphenyl,

(CH₂)_nCOOR₂ where n = 1 -4;

f) wherein R₂ is H, an alkali metal salt, an alkaline earth metal salt, NH₄ ⁺, N⁺(R₃)₄

wherein R₃ is each independently selected from the group consisting of H and

alkyl of 1 to 4 carbon atoms,

g) COR_! wherein R, is selected from the group consisting of H, (CH₂)_nCH₃

wherein n = 0-6, (CH₂)_nCOOR₂ wherein n = 1-4 and R₂ is as previously

defined, and (CH₂)_n N⁺(R₃)₃, wherein n = 1-4, wherein the effective amount is sufficient to ameliorate the manifestation of at least

one symptom of said disease.

These, and other objects, features and advantages of the present invention will

become apparent when read in conjunction with the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows the prophylactic effect of JO-4A on the level of parasitemia of

Plasmodium berghei malaria parasites in the blood of mice infected with the murine

parasites. C57BL/6 inbred strains of mice were pretreated intraperitoneally (i.p.) for 3 days

with 1.0 mg kg of JO-4A. On the 4th day, mice were infected with live parasites. Blood

samples were obtained from the mice on days 2, 3, 4, and 5 post infection to determine the

level of blood parasitemia. The results demonstrate that pretreatment of mice with J0-4A

prior to infection with malaria parasites dramatically reduced the level of parasitemia in

the blood in the first four days of infection.

Figure 2 shows the combined prophylactic and therapeutic effects of JO-4A on the

survival of mice infected with P. berghei parasites, 8 days post infection. Mice in the

different groups (10 mice per group) were pretreated per oral (p.o.) daily for 5 days with

varying doses of JO-4A in water (31.25 μg/kg, 62.5 μg/kg, 125.0 μg/kg and 250.0

μg/kg). The control group was given water only. On the 5th day of JO-4A pretreatment; all

mice were infected with P. berghei parasites i.p. Daily treatment with JO-4A was

continued for 3 days post-infection. The results depicted in Figure 2 were obtained 8 days

post infection with P. berghei parasites. Whereas all mice in the control group which did not receive JO-4A, died by day 8 post infection with P. berghei parasites, none of the mice

treated with 125.0 μg/kg of JO-4A, died by this day.

Figure 3 is an extension of the results in Figure 2. Figure 3 shows the actual day of

death of individual mouse in each group over a 24-day period. The group of mice

administered with 125 μg/kg of JO-4A survived the longest (about 3 times longer than the

control group).

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present inventors have conceived of, isolated and applied compounds JO-4 and

JO-4A against nucleated infectious agents comprising parasites, bacteria, and the like

microorganisms. Fungi and insects likewise are targeted by the instant teachings.

1. General Description and Definitions

The practice of the present invention will employ, unless otherwise indicated,

conventional laboratory animal handling techniques, microbiology, parasitology, organic

and medicinal chemical synthesis within the skill of the art. Such techniques are explained

fully in the literature. See Miller, L.H.; et al., eds; Immunity to Blood Parasites of Animals

and Man, Plenum Press, New York and London, 1977; Baker, J.R. Muller R, and

Rollinson, D. eds., Advances in Parasitology Vol.43, Academic Press, 1999; Bogitsh B.J.

and Chen T.C. eds. Human Parasitology 2nd edition, Academic Press, 1998; Murray, P.R

et al. eds; Medical Microbiology. Third edition, Mosby, St. Louis, MO., 1998;

Ojo-Amaize, E.A. et al. Plasmodium berghei Sporozoites are Mitogenic for Murine T

cells, induce Interferon and Activate Natural killer Cells, J. Immunol. 1984,

133:1005-1009; Ojo-Amaize, E.A. et al. Positive Correlation between degree of

parasitemia, interferon titers, and natural killer cell activity in Plasmodium Falciparum- infected Children, J. Immunol. 1981, 127:2296-2300; Silverman, R.B; The organic

chemistry of Drug Design and Drug Action, Academic Press, Inc. NY (1992); Smith,

M.B.; Organic Synthesis, McGraw Hill, Inc. NY, (1994); Okogun, J. I. et al., Z.

Naturforsch , 37c:558-561, 1982; Adesomoju, A. A. et al., Phytochemistry 22:2535-236,

1983. Likewise, artisans will understand those conventional techniques used to practice

the instant teachings.

The following terminology will be used in accordance with the definitions set out

below in describing the present invention.

The term "inhibiting the growth of is used with respect to protozoan parasites that

are pathological to humans or other animals. For example, with respect to protozoan

malarial parasites, "inhibiting the growth of means inhibition of parasitemia as

determined by decreased numbers of parasitized red cells in blood which results in

alleviating the "pathological effects" of malaria infection and increasing the life span of

infected subject.

The term "pathological effects" as used herein is illustrated by an understanding of

the life cycle of the protozoan parasite and its effects in a host. It will be understood that

protozoans, including those of the genus Plasmodium, Trypanosoma, Theileria, Babesia,

Coccidia, Amoebae and the like ciliates (including microsporidians), Trichomonad and

related forms, Non-trichomonad flagellates, hemoflagellates (such as Leishmania,

Trypanosoma), and other apicomplexans such as Bahesia, Toxoplasma, Pneumocystis,

Cryptosporidium, Cyclospora and Isospora are described herein. (Bogitsh, B.J. and

Cheng, T.C. eds. Human Parasitology 2nd edition, 1998: Academic Press, San Diego,

London, Boston, New York etc.). The protozoan plasmodial parasite causes Malaria, one of the most debilitating

diseases afflicting humans and animals. Plasmodia are nucleated Coccidian or Sporozoan

parasites of blood cells, and as seen with other coccidia, they require two hosts: the

mosquito for the sexual reproductive stages and humans and other animals for the asexual

reproductive stages. Human infection is initiated by the bite of an Anopheles mosquito,

which introduces infectious plasmodia sporozoites via its saliva into the circulatory

system. The sporozoites are carried to the parenchymal cells of the liver where asexual

reproduction (schizogony) occurs. This phase of growth is termed the exoerythrocytic

cycle and lasts 8-25 days depending on the plasmodial species. The hepatocytes eventually

rupture, liberating the plasmodia (termed merozoites at this stage), which in turn attach to

specific receptors on the surface of erythrocytes and enter the cells, thus initiating the

erythrocytic cycle. Asexual replication progresses through a series of stages (ring,

trophozoite, schizont) that culminates in the rupture of the erythrocyte, releasing

merozoites, which initiates another cycle of replication by infecting other erythrocytes

(Murray, P.R. et al. eds. Medical MicroBiology 3rd edition, 1998: Mosby-Year Book, Inc.,

St. Louis, MO.).

Pathological and clinical syndromes of malarial parasites consist, in part, of

influenza-like symptoms with fever patterns, severe nausea, vomiting and diarrhea, anemia

due to destruction of increased numbers of infected erythrocytes resulting in toxic cellular

debris, adherence of red blood cells to vascular endothelium and to adjacent red blood

cells, and formation of capillary plugging by masses of red blood cells, platelets,

leukocytes, and malarial pigment. It is also known that involvement of the brain (cerebral malaria) is most often seen

in P. falciparum infection. Capillary plugging from an accumulation of malarial pigment

and masses of red cells can result in coma and death. Kidney damage is also associated

with P. falciparum malaria resulting in an illness called blackwater fever.

Intravascular hemolysis with rapid destruction of red blood cells produces a

marked hemoglobinuria and can result in acute renal failure, tubular necrosis, nephrotic

syndrome, and death. Liver involvement is characterized by abdominal pain, vomiting of

bile, severe diarrhea, and rapid dehydration. Although any malaria infection may be fatal,

P. falciparum is the most likely to result in death if left untreated. In rodents, P. berghei,

and P. chabaudi infections result in death (Miller, L.H. et al. eds. Immunity to blood

parasites of animals and man: Advances in Experimental Medicine and Biology, Volume

93, 1977: Plenum Press, New York and London).

As used herein, the term "alleviate" means to mitigate, lessen or reduce or make

more bearable. The term "subject" is taken to mean humans as well as other animals.

The following materials and methods were employed in the non-limiting Examples

set out below, which illustrate unexpected results noted, those skilled in the art will

understand use of the instant teachings with known nucleated infectious agents.

Parasite Strain: P. berghei berghei (El Strain Clone B6 of 125674 SF-2393) was

purchased from American Type Culture Collection (ATCC), Rockville, MD. The parasites

were maintained in vivo and routinely passaged in C57BL/6 strains of mice. Animals: Animals used in this work were female C57BL/6 mice, 6-8 wk old, purchased

from Charles River Laboratories, Wilmington, MA.

Parasite Maintenance in vivo: One vial containing 0.5 ml of P. berghei-infected frozen

mouse blood, obtained from ATCC, was thawed and injected intraperitoneally (i.p.) into a

single mouse. When the mouse was sick, blood was collected by ocular venipuncture into

a heparinized tube. Giemsa stained thin blood film smears on glass slides were prepared to

determine the level of parasitemia by light microscopy. Infected blood was diluted 1 :1000

in HBSS (Hanks Balanced Salt Solution) and 0.3 ml was injected i.p. into a fresh

(uninfected) mouse. This process was repeated serially for parasite maintenance in vivo.

Parasite Staining and Diagnosis: The level of parasitemia was determined by standard

technology with thin smears of fresh blood on glass slides, fixed with absolute methanol

for 5 minutes, and stained for 30 minutes with 5% Giemsa dye buffered to pH 7.0 to 7.2

(Ojo-Amaize, E.A. et al. J. Immunol. 1981, 127:2296-2300; Murray, P.R. et al. eds.

Medical Microbiology. Third edition, Mosby, St. Louis, MO; 1998). Stained parasitized

red blood cells on glass slides were viewed with 100 x 1.25 objective lenses in oil

immersion under a light microscope (Nikon). At least 1000 red blood cells (RBCs) were

counted in each field and 5 fields were counted per slide. The total number of parasitized

cells per 1000 RBCs per field was recorded and the average was calculated per slide and

expressed in percent (%) of total RBCs. Treatment of Mice with JO-4A: For determination of the prophylactic effect of JO-4A on

level of blood parasitemia, 5 mice were pretreated p.o. with 1.0 mg/kg once a day for 3

days. Five control mice received vehicle (water) only. On the 4th day after drug

pretreatment was stopped, all mice were infected i.p. with 0.1 ml of infected blood diluted

1 : 100 in HBSS. Blood Samples were obtained from experimental and control mice on

days 2,3,4 and 5 post infection to determine the level of blood parasitemia. For

determination of mortality, there were 5 groups of 10 mice per group (No drug control,

31.2 μg/kg, 62.5 μg/kg, 125.0 μg/kg and 250 μg/kg). Experimental mice received

appropriate doses of J0-4A p.o. once a day for 4 days prior to infection with P. berghei

parasites on the 5th day of JO-4A pretreatment. Treatment with J0-4A was continued for 3

more days, once daily, post infection. Mortality of mice was followed daily for 24 days

and recorded.

While clinical data and involved mechanisms remain to be further developed it is

believed those skilled in the art will readily understand that treatment by the instant

compounds and methods for fungal-insect-based, and the like microbiological nucleated

agent mediated insult and injury would be routine using any conventional modes of

administration, comprising those falling within the scope of the instant claims and such

usages and applications would not require undue experimentation to artisans.

Having merely described aspects of the best modes to practice those preferred

embodiments which would enable artisans to fully comprehend and practice the teachings

of the present invention, it is further noted that various modifications, changes,

ameliorations and alterations may be effected by those skilled in the art without impacting

on the scope of spirit of the instant invention as defined by the appended claims. Likewise, the present inventors have used the instant compound to combat related

microbiological issues and challenges. For example, it has further been hypothecated that

tissues and systems insulted by fungal infestation exhibit with similarly shown

improvement under JO-4A treatment.

Claims

WHAT IS CLAIMED IS:

1. A therapeutic method for treating a subject having a disease caused by

infection with a protozoan parasite, comprising inhibiting the growth of said parasite by

administering to said subject an effective amount of at least one compound, or a

pharmaceutically acceptable prodrug of said compound, said compound having the

structural formula I:

wherei

b) P(O)(OH)₂,

c) P(O)(OH)(OM), wherein M is an alkali metal salt, or an alkaline earth

metal salt,

d) P(O)OM₂ wherein M is each independently selected from the group

consisting of alkali metal salts and alkaline earth metal salts,

e) Alkyl of 1 to 12 carbon atoms substituted or unsubstituted, straight chain or

branched, 0 to 6 double bonds, (CH₂)_n morpholine where n = 1-4,

morpholinomethylphenyl, ortho-aminophenyl, ortho-hydroxyphenyl,

(CH₂)_nCOOR₂ where n = 1-4; wherein R₂ is H, an alkali metal salt, an alkaline earth metal salt,

NH₄ ⁺, N⁺(R₃)₄ wherein R₃ is each independently selected from the group

consisting of H and alkyl of 1 to 4 carbon atoms,

f) COR1 wherein Rl is selected from the group consisting of H, (CH₂)_πCH₃

wherein n = 0-6, (CH₂)_nCOOR₂ wherein n = 1 -4 and R₂ is as previously

defined, and (CH₂)_n N⁺(R₃)₃, wherein n = 1-4,

wherein the effective amount is sufficient to ameliorate at least one

symptom of said disease, alone or in conjunction with other compounds

directed to the subject's disease.

2. The method of claim 1, wherein said protozoan parasite belongs to a

classification selected from the group consisting of Plasmodium, Trypanosoma,

Theileria, Babesia, Amoebae, ciliates including microsporidians, Trichomonas, non-

trichomonad flagellates, hemoflagellates, Leishmania, Toxoplasma, Pneumocystis,

Cryptosporidium, Cyclospora, Isospora, and Coccidia.

3. The method of claim 2 wherein said protozoan parasite belongs to a

classification selected from the group consisting of Plasmodium falciparum,

Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, Plasmodium berghei,

and Plasmodium chabaudi, Plasmodium knowlesi, Plasmodium cynomolgi,

Plasmodium lophurae and Plasmodium yoelii.

4. The method of claim 1 wherein R is H in said compound or a

pharmaceutically acceptable prodrug thereof.

5. The method of claim 1 wherein R is H in said compound or a

pharmaceutically acceptable prodrug thereof, and said disease is malaria.

6. The method of claim 3 wherein R is H in said compound or a

pharmaceutically acceptable prodrug thereof.

7. A prophylactic method for protecting a subject in danger of contracting

disease caused by infection with a protozoan parasite, comprising inhibiting the

growth of said parasite by administering to said subject an effective amount of at least

one compound, or pharmaceutically acceptable prodrug of said compound, said

compound having the structural formula I:

where

b) P(O)(OH)₂, c) P(O)(OH)(OM), wherein M is an alkali metal salt, or an alkaline earth

metal salt,

d) P(O)OM₂ wherein M is each independently selected from the group

consisting of alkali metal salts and alkaline earth metal salts,

e) alkyl of 1 to 12 carbon atoms substituted or unsubstituted, straight chain

or branched, 0 to 6 double bonds, (CH₂)_n morpholine where n = 1-4,

morpholinomethylphenyl, ortho-aminophenyl, ortho-hydroxyphenyl,

(CH₂)_nCOOR₂ where n = 1-4;

f) wherein R₂ is H, an alkali metal salt, an alkaline earth metal salt, NH₄ ⁺,

N⁺(R₃)₄ wherein R₃ is each independently selected from the group

consisting of H and alkyl of 1 to 4 carbon atoms,

g) COR, wherein R, is selected from the group consisting of H, (CH₂)_nCH₃

wherein n = 0-6, (CH₂)„COOR₂ wherein n = 1-4 and R₂ is as previously

defined, and (CH₂)_n N⁺(R₃)₃, wherein n = 1 -4,

wherein the effective amount is sufficient to ameliorate the manifestation of at

least one symptom of said disease.

8. The method of claim 7, wherein said protozoan parasite belongs to a

classification selected from the group consisting of Plasmodium, Trypanosoma,

Theileria, Babesia, Amoebae, ciliates including microsporidians, Trichomonas, non-

trichomonad flagellates, hemoflagellates, Leishmania, Toxoplasma, Pneumocystis,

Cryptosporidium, Cyclospora, Isospora, and Coccidia.

9. The method of claim 8 wherein said protozoan parasite belongs to a

classification selected from the group consisting of Plasmodium falciparum,

Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, Plasmodium berghei,

and Plasmodium chabaudi, Plasmodium knowlesi, Plasmodium cynomolgi,

Plasmodium lophurae and Plasmodium yoelii.

10. The method of claim 7 wherein R is H in said compound or a

pharmaceutically acceptable prodrug thereof.

11. The method of claim 7 wherein R is H in said compound or a

pharmaceutically acceptable prodrug thereof, and said disease is malaria.

12. The method of claim 9 wherein R is H in said compound or a

pharmaceutically acceptable prodrug thereof.

13. An article of manufacture for performing the therapeutic method of

claim 1, comprising packaging material containing said at least one compound, or

pharmaceutically acceptable prodrug of said at least one compound, and said

packaging material includes a label that describes said at least one compound, or

pharmaceutically acceptable prodrug of said at least one compound, as useful for

treating a subject having a disease caused by infection with a protozoan parasite.

14. An article of manufacture for performing the prophylactic method of

claim 7, comprising packaging material containing said at least one compound, or

pharmaceutically acceptable prodrug of said at least one compound, and said

packaging material includes a label that describes said at least one compound, or

pharmaceutically acceptable prodrug of said at least one compound, as useful for

protecting a subject in danger of contracting disease caused by infection with a

protozoan parasite, alone or in conjunction with other compounds.

15. A composition effective to treat a subject having a disease caused by

infection with a protozoan parasite comprising a first compound, or a

pharmaceutically acceptable prodrug of said compound, which functions as a parasite

growth inhibitor in the therapeutic method of claim 1, in combination with a second

compound, or a pharmaceutically acceptable salt of said compound, which is

antiparasitic.

16. A composition effective to protect a subject in danger of contracting

disease caused by infection with a protozoan parasite comprising a first compound, or

a pharmaceutically acceptable prodrug of said compound, which functions as a

parasite growth inhibitor in the prophylactic method of claim 7, in combination with a

second compound, or a pharmaceutically acceptable salt of said compound, which is

antiparasitic.

17. A pharmaceutical composition formulated for single dosage

administration, comprising an effective amount of at least one compound effective in

the therapeutic method of claim 1, or a pharmaceutically acceptable prodrug of said

compound, wherein the amount is sufficient to ameliorate at least one symptom of

said disease.

18. A pharmaceutical composition formulated for single dosage

administration, comprising an effective amount of at least one compound effective in

the prophylactic method of claim 7, or a pharmaceutically acceptable prodrug of said

compound, wherein the amount is sufficient to ameliorate the manifestation of at least

one symptom of said disease.

19. A pharmaceutical composition formulated for single dosage

administration, comprising an effective amount of the compound effective in the

therapeutic method of claim 5, or a pharmaceutically acceptable prodrug of said

compound, wherein the amount is sufficient to ameliorate at least one symptom of

malaria.

20. A pharmaceutical composition formulated for single dosage

administration, comprising an effective amount of the compound effective in the

prophylactic method of claim 11, or a pharmaceutically acceptable prodrug of said

compound, wherein the amount is sufficient to ameliorate the manifestation of at least

one symptom of malaria.