title: Efficacy of Indian polyvalent snake antivenoms against Sri Lankan snake venoms: lethality studies or clinically focussed in vitro studies.
abstract: In vitro antivenom efficacy studies were compared to rodent lethality studies to test two Indian snake antivenoms (VINS and BHARAT) against four Sri Lankan snakes. In vitro efficacy was tested at venom concentrations consistent with human envenoming. Efficacy was compared statistically for one batch from each manufacturer where multiple vials were available. In binding studies EC50 for all VINS antivenoms were less than BHARAT for D. russelii [553 μg/mL vs. 1371 μg/mL;p = 0.016), but were greater for VINS antivenoms compared to BHARAT for N. naja [336 μg/mL vs. 70 μg/mL;p < 0.0001]. EC50 of both antivenoms was only slighty different for E. carinatus and B. caeruleus. For procoagulant activity neutralisation, the EC50 was lower for VINS compared to BHARAT - 60 μg/mL vs. 176 μg/mL (p < 0.0001) for Russell's viper and 357 μg/mL vs. 6906μg/mL (p < 0.0001) for Saw-scaled viper. Only VINS antivenom neutralized in vitro neurotoxicity of krait venom. Both antivenoms partially neutralized cobra and didn't neutralize Russell's viper neurotoxicity. Lethality studies found no statistically significant difference in ED50 values between VINS and BHARAT antivenoms. VINS antivenoms appeared superior to BHARAT at concentrations equivalent to administering 10 vials antivenom, based on binding and neutralisation studies. Lethality studies were inconsistent suggesting rodent death may not measure relevant efficacy outcomes in humans.
authors.affiliation: Clinical Toxicology Research Group, University of Newcastle, NSW, Australia.|South Asian Clinical Toxicology Research Collaboration (SACTRC), Faculty of Medicine, University of Peradeniya, Peradeniya, Sri Lanka.
authors.forename: Kalana
authors.initials: K
authors.lastname: Maduwage
authors.affiliation: Department of Pharmacology, Monash Venom Group, Monash University, Clayton, Victoria, Australia.|Department of Parasitology, Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka, Anuradhapura, Sri Lanka.
authors.forename: Anjana
authors.initials: A
authors.lastname: Silva
authors.affiliation: Clinical Toxicology Research Group, University of Newcastle, NSW, Australia.
authors.forename: Margaret A
authors.initials: MA
authors.lastname: O'Leary
authors.affiliation: Department of Pharmacology, Monash Venom Group, Monash University, Clayton, Victoria, Australia.
authors.forename: Wayne C
authors.initials: WC
authors.lastname: Hodgson
authors.affiliation: Clinical Toxicology Research Group, University of Newcastle, NSW, Australia.|South Asian Clinical Toxicology Research Collaboration (SACTRC), Faculty of Medicine, University of Peradeniya, Peradeniya, Sri Lanka.
authors.forename: Geoffrey K
authors.initials: GK
authors.lastname: Isbister
mesh_terms: D000818:Animals; D000997:Antivenins / Q000494:pharmacology*; D002645:Chickens; D003029:Coagulants / Q000494:pharmacology; D066298:In Vitro Techniques; D018482:Muscle, Skeletal / Q000187:drug effects / Q000294:innervation; D012910:Snake Venoms / Q000493:pharmacokinetics* / Q000633:toxicity*; D012911:Snakes; D013188:Sri Lanka
chemical_list: D000997:Antivenins; D003029:Coagulants; D012910:Snake Venoms