Adverse Events in the Efficacy of Crotalidae Polyvalent Immune Fab Antivenom vs Placebo in Recovery from Copperhead Snakebite Trial.

Abstract

OBJECTIVE:

To compare the incidence of hypersensitivity reactions following copperhead envenomation treated with Fab antivenom (FabAV) or placebo.

METHODS:

Patients with copperhead snakebites received treatment and follow-up in a prospective, randomized, double-blind, placebo-controlled trial of FabAV or placebo. The treatment allocation ratio was 2:1 (FabAV:placebo). All of the included patients received at least one dose of study treatment. We reviewed all treatment-emergent adverse events (AEs) using a previously published scale to classify likely hypersensitivity reactions as mild, moderate, or severe.

RESULTS:

We enrolled 74 patients at 13 sites. Forty-five patients received FabAV, and 29 patients received placebo. Five FabAV patients and 4 placebo patients had moderate envenomations; the rest were mild. Twenty-five FabAV patients and 8 placebo patients had at least 1 AE. Mild skin reactions occurred in 11 (24%) FabAV patients (pruritis, urticaria, rash, ecchymosis, erythema) and 1 (3%) placebo patient (pruritis). Moderate gastrointestinal AEs occurred in 7 (16%) FabAV patients (nausea, vomiting, constipation, diarrhea, oral paresthesia) and in 2 (7%) placebo patients (nausea). Respiratory AEs occurred in 3 (7%) FabAV patients (dyspnea, pulmonary embolism, nasal congestion, sneezing) and no placebo patients. Hypotension occurred in 1 patient in each group.

CONCLUSIONS:

In a randomized controlled trial of FabAV for copperhead bites, the incidence of hypersensitivity reactions was low. Most reactions were mild skin reactions.

• Authors: Michael E Mullins, Charles J Gerardo, Sean P Bush, S Rutherfoord Rose, Spencer Greene, Eugenia B Quackenbush, Brandon Lewis, Victoria E Anderson, Kurt C Kleinschmidt, Richard B Schwarz, Nathan P Charlton, Eric A Toschlog, Kapil Sharma, David A Denning, Eric J Lavonas
• Journal: Southern medical journal (South Med J) Vol. 111 Issue 12 Pg. 716-720 (12 2018) ISSN: 1541-8243 [Electronic] United States
• PMID: 30512122 (Publication Type: Journal Article, Multicenter Study, Randomized Controlled Trial)

Chemical References

• Antivenins
• Crotalidae Polyvalent immune Fab
• Immunoglobulin Fab Fragments

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Agkistrodon
• Animals
• Antivenins (adverse effects, therapeutic use)
• Child
• Double-Blind Method
• Drug Hypersensitivity (epidemiology, etiology)
• Female
• Follow-Up Studies
• Humans
• Immunoglobulin Fab Fragments (adverse effects, therapeutic use)
• Incidence
• Male
• Middle Aged
• Prospective Studies
• Snake Bites (drug therapy)
• Treatment Outcome
• Young Adult