The antiviral activity of SP-303, a natural polyphenolic polymer, against respiratory syncytial and parainfluenza type 3 viruses in cotton rats.
SP-303, a naturally occurring polyphenolic polymer (average M.W. = 2100 Da), was tested in cotton rats (Sigmoden hispidus) for antiviral activity against respiratory syncytial (RSV) and parainfluenza type 3 (PIV3) viruses, and for acute toxicity. Significant reductions in pulmonary RSV titers, compared to pulmonary RSV titers in comparably treated control animals, were seen in cotton rats given 1-10 mg SP-303/kg/day intraperitoneally (i.p.) on days 1 through to 3, after experimental inoculation with RSV. The minimum efficacious dose of SP-303 against PIV3, when given i.p. for 3 days, was 3 mg/kg/day. Higher doses of SP-303 could not be given i.p., as doses > or = 30 mg/kg/day given once daily by this route for 3 or more consecutive days caused both significant weight loss and death in infected or uninfected animals. Although no toxicity was observed following oral administration of up to 270 mg of SP-303 daily for 3 days, this compound had variable antiviral activity when given by this route.
Wyde
P R
PR
Department of Microbiology and Immunology, Baylor College of Medicine, Houston, TX 77030.
Ambrose
M W
MW
Meyerson
L R
LR
Gilbert
B E
BE
D000818:Animals; D000998:Antiviral Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001704:Biopolymers / Q000494:pharmacology*; D001835:Body Weight; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D046508:Culture Techniques; D008168:Lung / Q000382:microbiology / Q000473:pathology; D010224:Parainfluenza Virus 3, Human / Q000187:drug effects*; D018184:Paramyxoviridae Infections / Q000382:microbiology / Q000517:prevention & control*; D010946:Plants, Medicinal / Q000737:chemistry; D012136:Respiratory Syncytial Viruses / Q000187:drug effects*; D010253:Respirovirus Infections / Q000382:microbiology / Q000517:prevention & control*; D012254:Ribavirin / Q000494:pharmacology; D016205:Sigmodontinae; D010948:Viral Plaque Assay; D044945:Proanthocyanidins
D000998:Antiviral Agents; D001704:Biopolymers; D002392:Catechin; D012254:Ribavirin; C546704:crofelemer; D044945:Proanthocyanidins