Pre-clinical and preliminary dose-finding and safety studies to identify candidate antivenoms for treatment of envenoming by saw-scaled or carpet vipers (Echis ocellatus) in northern Nigeria

Antivenomic Assessment of the Immunological Reactivity of EchiTAb-Plus-ICP, an Antivenom for the Treatment of Snakebite Envenoming in Sub-Saharan Africa

“…4 Thus, the effective immunodepletion of SVMPs and serine proteinases by the EchiTAb-Plus-ICP antivenom correlates well with our earlier reports of the preclinical venom-neutralizing effectiveness of this antivenom against these important African vipers (using assays of venom-induced lethality, hemorrhage, and coagulation 19,20 and its clinical efficacy in treating human victims of E. ocellatus envenoming. 27 The partial immunological reactivity to some PLA 2 s, disintegrins, and proteinase inhibitors revealed the presence of low affinity or low abundance of antibodies against these components in the antivenom. Previous studies on antivenoms that target a number of venoms of Central and South American viper species showed evidence that PLA 2 s and other lowmolecular-mass components were poorly immunogenic, thus resulting in the generation of low-affinity antibodies.…”

“…20 Moreover, this antivenom proved clinically effective and safe in a powerful trial performed in Nigeria in patients systemically envenomed by E. ocellatus. 27 In addition to preclinical neutralization tests, a complementary approach to assess the immunoreactivity of antivenoms against individual venom components has been recently developed. It is known as "antivenomics" and is based on the application of proteomic analytical tools for studying venoms and antivenoms.…”

Snakebite Envenoming: A Public Health Perspective

“…Since phase I clinical trials in healthy volunteers are ethically unacceptable in the case of antivenoms, because they might induce adverse reactions, a substitution of phase I clinical trial, by a protocol known as '3 + 3 dose escalation design', has been proposed for antivenoms (S.B. Abubakar et al, 2010b). This is then followed by phase III clinical trials in which a new antivenom is compared with an existing antivenom of known efficacy and safety (see for example the studies of I.S.…”

Optimization of purification procedure for horse F(ab´)2 antivenom against <i>Androctonus crassicauda</i> (Scorpion) venom

“…Scientists used ammonium or sodium sulfate to precipitate immunoglobulin from immunized plasma. Although salt precipitation methods leads to high yields but contamination may occur with other proteins, such as albumin and digested Fc fragment [12].…”

“…In addition, it is generally used alone or in combination with salt precipitation in order to purify immunized plasma from both equine and ovine origins [13]. Furthermore, caprylic acid is an unsaturated fatty acid and a good precipitating agent for undesired proteins from animal plasma essentially albumin without any effect on immunoglobulin fraction [14]. Thus, producers can implement caprylic acid in the present method for a successful purification as the replacement for the old process based on precipitation with ammonium or sodium sulfate [15].…”