A controlled clinical trial of a novel antivenom in patients envenomed by Bungarus multicinctus

Abstract

In northern Vietnam, a majority of severely envenomed patients are bitten by Bungarus multicinctus. Hitherto, these victims have received supportive care only. The aims of this study were to assess the possible efficacy and side effects of a new antivenom. This trial (ClinicalTrials.gov Identifier: NCT00811239) was performed during 2004-2006 at an ICU in Hanoi. For ethical reasons, the study was not randomized. All patients who fulfilled the inclusion criteria during 2004-2005 were prospectively enrolled, carefully recorded, and treated with optimal supportive therapy (control group). The patients who entered the study 2006 were treated with antivenom in addition to supportive care (antivenom group). The inclusion criteria were: envenomation by B. multicinctus, presence of systemic envenomation, and (during 2006) provision of written informed consent. Predefined endpoints were number of patients requiring mechanical ventilation, duration of mechanical ventilation, length of ICU stay, duration of muscle paralysis, and number of patients with ventilator-associated pneumonia. Eighty-one patients were included, 54 during 2004-2005 and 27 during 2006. Baseline characteristics were similar in the groups. The antivenom-group patients had a shorter duration of muscle paralysis of the limbs (p < 0.001), of the diaphragm (p < 0.001), and of ptosis (p < 0.001). The duration of mechanical ventilation and length of ICU stay were shorter in the antivenom group (p < 0.001). The rate of ventilator-associated pneumonia was lower in the antivenom group (p < 0.02). However, the relative number of patients requiring mechanical ventilation was not reduced in the antivenom group. The rate of adverse reactions to the antivenom was 7.4%. A favorable efficacy and acceptable safety of this antivenom were demonstrated.