proguanil hydrochloride

Proguanil hydrochloride, an antimalarial prodrug, is metabolized to the active metabolite Cycloguanil (HY-12784). Proguanil hydrochloride is a dihydrofolate reductase (DHFR) inhibitor[1][2].

Research Areas >> Infection

Signaling Pathways >> Cell Cycle/DNA Damage >> Antifolate

Proguanil per se has only weak antimalarial activity in vitro (IC50=2.4-19 μM), and its effectiveness depends on the active metabolite Cycloguanil (IC50=0.5-2.5 nM). The Cycloguanil is a dihydrofolate reductase (DHFR) inhibitor. The combination of Atovaquone and Proguanil is synergistic in vitro. Both drugs also have activity against gametocytes and pre-erythrocytic (hepatic) stages of malaria parasites[1]. Proguanil acts as a biguanide rather than as its metabolite Cycloguanil (a parasite dihydrofolate reductase [DHFR] inhibitor) to enhance the Atovaquone effect. Proguanil-mediated enhancement is specific for Atovaquone, since the effects of other mitochondrial electron transport inhibitors, such as Myxothiazole and Antimycin, are not altered by inclusion of Proguanil[2]. 5-HT3 receptor responses are reversibly inhibited by Proguanil, the metabolite 4-chlorophenyl-1-biguanide (CPB) and the active metabolite Cycloguanil (CG), with an IC50 of 1.81, 1.48 and 4.36 μM, respectively[3].

Proguanil (p.o.; 2.9 mg/kg body weight; daily for 5 days and 6 weeks respectively) shows mild degenerative changes for five days, while shows severe degenerative changes for six weeks in wistar strain albino rats[4]. Serum testosterone level is significantly decreased for proguanil treatment rats[4]. Administration of Malarone (Atovaquone and Proguanil) to experimentally B. gibsoni infected two dogs in chronic stage and three dogs in acute stage results in decrease in parasitemia, and clinical improvements are observed[5].

[1]. Pudney M, et al. Atovaquone and proguanil hydrochloride: a review of nonclinical studies. J Travel Med. 1999 May;6 Suppl 1:S8-12.

[2]. Srivastava IK, et al. A mechanism for the synergistic antimalarial action of atovaquone and proguanil. Antimicrob Agents Chemother. 1999 Jun;43(6):1334-9.

[3]. Lochner M, et al. The antimalarial drug proguanil is an antagonist at 5-HT3 receptors. J Pharmacol Exp Ther. 2014 Dec;351(3):674-84.

[4]. Stephen AO, et al. Prolonged administration of proguanil induces reproductive toxicity in male rats. J Toxicol Sci. 2011 Oct;36(5):587-99.

[5]. Iguchi A, et al. The in vitro interactions and in vivo efficacy of atovaquone and proguanil against Babesia gibsoni infection in dogs. Vet Parasitol. 2013 Nov 8;197(3-4):527-33.

MOLECULAR FORMULA :

C11-H16-Cl-N5.Cl-H

MOLECULAR WEIGHT :

290.23

WISWESSER LINE NOTATION :

GR DMYUM&MYUM&MY1&1 &GH

HEALTH HAZARD DATA

ACUTE TOXICITY DATA

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Oral

SPECIES OBSERVED :

Rodent - rat

DOSE/DURATION :

58 mg/kg

TOXIC EFFECTS :

Details of toxic effects not reported other than lethal dose value

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 91,157,1947

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Intravenous

SPECIES OBSERVED :

Rodent - rat

DOSE/DURATION :

33 mg/kg

TOXIC EFFECTS :

Behavioral - altered sleep time (including change in righting reflex) Behavioral - convulsions or effect on seizure threshold

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 91,157,1947

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Oral

SPECIES OBSERVED :

Rodent - mouse

DOSE/DURATION :

27 mg/kg

TOXIC EFFECTS :

Details of toxic effects not reported other than lethal dose value

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 91,157,1947

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Subcutaneous

SPECIES OBSERVED :

Rodent - mouse

DOSE/DURATION :

35 mg/kg

TOXIC EFFECTS :

Details of toxic effects not reported other than lethal dose value

REFERENCE :

TXAPA9 Toxicology and Applied Pharmacology. (Academic Press, Inc., 1 E. First St., Duluth, MN 55802) V.1- 1959- Volume(issue)/page/year: 2,474,1960

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Intravenous

SPECIES OBSERVED :

Rodent - mouse

DOSE/DURATION :

23 mg/kg

TOXIC EFFECTS :

Behavioral - altered sleep time (including change in righting reflex) Behavioral - convulsions or effect on seizure threshold

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 91,157,1947

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Oral

SPECIES OBSERVED :

Rodent - rabbit

DOSE/DURATION :

150 mg/kg

TOXIC EFFECTS :

Details of toxic effects not reported other than lethal dose value

REFERENCE :

BJPCAL British Journal of Pharmacology and Chemotherapy. (London, UK) V.1-33, 1946-68. For publisher information, see BJPCBM. Volume(issue)/page/year: 2,181,1947

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Intravenous

SPECIES OBSERVED :

Rodent - rabbit

DOSE/DURATION :

44850 ug/kg

TOXIC EFFECTS :

Behavioral - altered sleep time (including change in righting reflex)

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 91,157,1947

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Intraperitoneal

SPECIES OBSERVED :

Rodent - guinea pig

DOSE/DURATION :

15 mg/kg

TOXIC EFFECTS :

Details of toxic effects not reported other than lethal dose value

REFERENCE :

TXAPA9 Toxicology and Applied Pharmacology. (Academic Press, Inc., 1 E. First St., Duluth, MN 55802) V.1- 1959- Volume(issue)/page/year: 2,474,1960

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Intravenous

SPECIES OBSERVED :

Rodent - guinea pig

DOSE/DURATION :

39510 ug/kg

TOXIC EFFECTS :

Behavioral - altered sleep time (including change in righting reflex) Behavioral - convulsions or effect on seizure threshold

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 91,157,1947

TYPE OF TEST :

LD50 - Lethal dose, 50 percent kill

ROUTE OF EXPOSURE :

Oral

SPECIES OBSERVED :

Bird - chicken

DOSE/DURATION :

400 mg/kg

TOXIC EFFECTS :

Details of toxic effects not reported other than lethal dose value

REFERENCE :

BJPCAL British Journal of Pharmacology and Chemotherapy. (London, UK) V.1-33, 1946-68. For publisher information, see BJPCBM. Volume(issue)/page/year: 2,181,1947 ** OTHER MULTIPLE DOSE TOXICITY DATA **

TYPE OF TEST :

TDLo - Lowest published toxic dose

ROUTE OF EXPOSURE :

Oral

SPECIES OBSERVED :

Rodent - rat

DOSE/DURATION :

350 mg/kg/7D-I

TOXIC EFFECTS :

Related to Chronic Data - death

REFERENCE :

BJPCAL British Journal of Pharmacology and Chemotherapy. (London, UK) V.1-33, 1946-68. For publisher information, see BJPCBM. Volume(issue)/page/year: 2,181,1947

TYPE OF TEST :

TDLo - Lowest published toxic dose

ROUTE OF EXPOSURE :

Oral

SPECIES OBSERVED :

Rodent - rat

DOSE/DURATION :

3088 mg/kg/9W-C

TOXIC EFFECTS :

Nutritional and Gross Metabolic - weight loss or decreased weight gain

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 90,233,1947

TYPE OF TEST :

TDLo - Lowest published toxic dose

ROUTE OF EXPOSURE :

Oral

SPECIES OBSERVED :

Rodent - mouse

DOSE/DURATION :

515 mg/kg/10D-C

TOXIC EFFECTS :

Behavioral - food intake (animal) Related to Chronic Data - death

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 90,233,1947

TYPE OF TEST :

TDLo - Lowest published toxic dose

ROUTE OF EXPOSURE :

Oral

SPECIES OBSERVED :

Mammal - dog

DOSE/DURATION :

709 mg/kg/31D-I

TOXIC EFFECTS :

Gastrointestinal - changes in structure or function of salivary glands Nutritional and Gross Metabolic - weight loss or decreased weight gain Related to Chronic Data - death

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 90,233,1947

TYPE OF TEST :

TDLo - Lowest published toxic dose

ROUTE OF EXPOSURE :

Oral

SPECIES OBSERVED :

Primate - monkey

DOSE/DURATION :

1006 mg/kg/22D-I

TOXIC EFFECTS :

Gastrointestinal - changes in structure or function of salivary glands Nutritional and Gross Metabolic - weight loss or decreased weight gain Related to Chronic Data - death

REFERENCE :

JPETAB Journal of Pharmacology and Experimental Therapeutics. (Williams & Wilkins Co., 428 E. Preston St., Baltimore, MD 21202) V.1- 1909/10- Volume(issue)/page/year: 90,233,1947 ** REPRODUCTIVE DATA **

TYPE OF TEST :

TDLo - Lowest published toxic dose

ROUTE OF EXPOSURE :

Oral

DOSE :

168 mg/kg

SEX/DURATION :

female 7 day(s) pre-mating female 1-7 day(s) after conception

TOXIC EFFECTS :

Reproductive - Fertility - female fertility index (e.g. # females pregnant per # sperm positive females; # females pregnant per # females mated)

REFERENCE :

ANTCAO Antibiotics and Chemotherapy (Washington, DC). (Washington, DC) V.1-12, 1951-62. For publisher information, see CLMEA3. Volume(issue)/page/year: 12,671,1962