Snake antivenoms: adverse reactions and production technology: [review]

Antivenoms have been widely used for more than a century for treating snakebites and other accidents with poisonous animais. Despite their efficacy, the use of heterologous antivenoms involves the possibility of adverse reactions due to activation of the immune system. In this paper, alternatives for antivenom production already in use were evaluated in light of their ability to minimize the occurrence of adverse reactions. These effects were classified according to their molecular mechanism as: anaphylactic reactions mediated by IgE, anaphylactoid reactions: aused by complement system activation, and pyrogenic reactions produced mainly by the presence of endotoxins in the final product. ln the future, antivenoms may be replaced by humanized antibodies, specific neutralizing compounds or vaccination. Meanwhile, improvements in antivenom quality will be focused on the obtainment of more purified and specific product in compliance with good manufacturing practices and at an affordable cost

Economic evaluation of snake antivenom production in the public system

Snake antivenom, an expensive animal product, is presently the only effective treatment for the consequences of snakebite. In Latin America, antivenoms are mainly produced by public institutions with frequent shortages of the necessary supply. Here, we present an economical analysis of the factors affecting production cost, assuming a basic processing batch of 100 L hyperimmune plasma. Three annual production volumes were considered for two typical production technologies. The components of cost were classified as fixed, variable and semi-variable. We found that in all stages of production, fixed cost represents the major contribution to total cost, and is given essentially by manpower cost, particularly for low production volumes. Our estimation shows that antivenom cost can vary from US$ 2.4 to US$ 25 per 10 mL vial, depending on the production volume, the plasma processing technology used and the titer achieved during the immunization stage. We conclude that interested laboratories and authorities of countries with population at risk should consider the possibility of a joint production to improve the process efficiency, lower the product unitary cost and obtain the necessary supply for their own demand or that of other countries in need