Antivenom preclinical efficacy testing against Asian snakes and their availability in Asia: A systematic review

PLoS One. 2023 Jul 19;18(7):e0288723. doi: 10.1371/journal.pone.0288723. eCollection 2023.

Abstract

Background: Cross-neutralizing strategy has been applied to improve access to antivenoms, a key to reducing mortality and disability of snakebite envenoming. However, preclinical studies have been conducted to identify antivenoms' cross-neutralizing ability when clinical studies may not be considered ethical. Therefore, this study aimed to identify and summarize scattered evidence regarding the preclinical efficacy of antivenoms against Asian snakes.

Methodology/principle findings: In this systematic review, we searched for articles published until May 30, 2022, in PubMed, Scopus, Web of Science, and Embase. Preclinical studies that reported the available antivenoms' neutralizing ability against Asian snake lethality were included. Quality assessment was performed using the Systematic Review Centre for Laboratory animal Experimentation's risk of bias tool and the adapted the Animal Research Reporting In Vivo Experiments guidelines. The availability of effective antivenoms against Asian snakes was analyzed by comparing data from included studies with snakebite-information and data platforms developed by the World Health Organization. Fifty-two studies were included. Most studies assessed the antivenom efficacy against snakes from Southeast Asia (58%), followed by South Asia (35%) and East Asia (19%). Twenty-two (49%) medically important snakes had antivenom(s) with confirmed neutralizing ability. Situation analyses of the availability of effective antivenoms in Asia demonstrated that locally produced antivenoms did not cover all medically important snakes in each country. Among countries without local antivenom production, preclinical studies were conducted only in Bangladesh, Sri Lanka, and Malaysia. Risk of bias assessment was limited in some domains because of unreported data.

Conclusions/significance: Cross-neutralizing of antivenoms against some medically important snakes in Asia was confirmed. This strategy may improve access to geographically effective antivenoms and bypass investment in novel antivenom development, especially in countries without local antivenom production. A database should be developed to aid the development of a snakebite-information system.

Publication types

  • Systematic Review
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antivenins*
  • Asia, Eastern
  • Snake Bites* / drug therapy
  • Snakes
  • Sri Lanka

Substances

  • Antivenins

Grants and funding

The authors would like to gratefully thank the scholarship provided to Miss Sutinee Soopairin from the Graduate School, Chulalongkorn University, to commemorate the 72nd anniversary of his Majesty King Bhumibol Adulyadej. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.”