Pilot Comparative Study

Anesthetic Activity of Vezotil® vs Zoletil® 100

Pilot Comparative Clinical Study

Veterinary Anesthesiology • 2025

Study Authors

E.A. Kornyushenkov

Lead Researcher, PhD in Veterinary Sciences

D.V. Vdovina

Veterinary Anesthesiologist

P.A. Anisimova

Research Associate

A.A. Shimshirt

Statistician

E.V. Viktorova

Data Analyst

Publication Data

Publication Date

May 20, 2025

Journal

Veterinary Anesthesiology

Article Type

Clinical Study

Status

Published

Abstract

This pilot study represents the first comprehensive comparison of anesthetic activity of new domestic drug Vezotil® with its original analog Zoletil® 100. The study was conducted to assess therapeutic equivalence and identify potential advantages of the Russian analog.

Study Objective

To conduct comparative evaluation of anesthetic activity of Vezotil® and Zoletil® 100 in cats and dogs, determine therapeutic equivalence and identify clinically significant differences in drug action.

Materials and Methods

Study Design

  • • Randomized controlled study
  • • Double-blind comparison
  • • Parallel groups
  • • Single-center study
  • • Prospective design

Inclusion Criteria

  • • Healthy animals (ASA I-II)
  • • Age 1 to 8+ years
  • • Body weight 2 to 45 kg
  • • Elective surgical procedures
  • • Informed owner consent

Anesthesia Protocol

Premedication

  • • Atropine 0.02-0.04 mg/kg SC
  • • 15-20 minutes before induction
  • • Salivation control

Induction

  • • Vezotil® or Zoletil® 100
  • • Dosage 10-15 mg/kg IM
  • • Single administration

Monitoring

  • • HR, RR, temperature
  • • Anesthesia depth
  • • Recovery quality

Study Results

Key Findings

🏆 Key Results

  • • Vezotil® demonstrated complete therapeutic equivalence to Zoletil® 100
  • • No statistically significant differences in main anesthesia parameters
  • • Vezotil® showed some advantages in sedative effect
  • • Both drugs showed high safety profile

Time Characteristics

Vezotil®

Onset: 3.2±0.8 min

Duration: 62±15 min

Recovery: 95±20 min

Zoletil® 100

Onset: 3.5±0.9 min

Duration: 58±18 min

Recovery: 102±25 min

p > 0.05 for all parameters

Quality Parameters

Anesthesia depth:Adequate (100%)
Muscle relaxation:Excellent
Sedative effect:Vezotil® > Zoletil®
Salivation:Vezotil® < Zoletil®

Statistical Analysis

Statistical Methods

Tests used:

  • • Student's t-test
  • • Mann-Whitney U test
  • • Pearson's χ² test
  • • Kaplan-Meier survival analysis

Significance level:

  • • α = 0.05 (p < 0.05)
  • • Study power: 80%
  • • Confidence interval: 95%
  • • Effect size: 0.3

Key Statistical Results

p >0.05
anesthesia onset time
p >0.05
duration of action
p >0.05
recovery time

📊 Statistical conclusion: Absence of statistically significant differences (p > 0.05) confirms therapeutic equivalence of the drugs.

Conclusions and Perspectives

Scientific Conclusions

1. Vezotil® demonstrated complete therapeutic equivalence to the original Zoletil® 100 across all main anesthetic activity parameters.

2. Some clinical advantages of Vezotil were identified: more pronounced sedation during induction and significantly less salivation.

3. Both drugs showed high safety profile when used at recommended dosages.

Clinical Significance

Results of this pilot study justify the possibility of using Vezotil® as an alternative to Zoletil® 100 in veterinary anesthesiological practice. This is especially important in the context of import substitution and ensuring availability of quality anesthetics for Russian veterinary clinics.

Further Research Perspectives

  • • Conducting larger-scale multicenter study
  • • Studying application in exotic animal species
  • • Pharmacoeconomic analysis
  • • Long-term safety studies
  • • Comparison with other anesthetics