Double-Blind, AlacramynÂ® vs. Placebo in Pediatric Patients
Information source: Instituto Bioclon S.A. de C.V.
Information obtained from ClinicalTrials.gov on June 20, 2008
Link to the current ClinicalTrials.gov record.
Condition(s) targeted: Scorpion Sting Envenomation
Intervention: Antivenin Centruroides (scorpion) equine immune F(ab)2 (Biological); Placebo (Other)
Phase: Phase 2/Phase 3
Sponsored by: Instituto Bioclon S.A. de C.V.
Official(s) and/or principal investigator(s):
Leslie Boyer, MD, Principal Investigator, Affiliation: Poison and Drug Center
Walter Garcia, MD, Study Director, Affiliation: Instituto Bioclon S.A. de C.V.
Alejandro Alagon, PhD, Study Chair, Affiliation: Instituto de Biotecnologia UNAM
There is no FDA approved therapy for the treatment of scorpion envenomation, Centruroides
scorpion envenomation produces a pattern of neurotoxicity with a spectrum of severity ranging
from trivial to life threatening. Patients stung by Centruroides scorpions develop a clinical
syndrome which may require sedation with benzodiazepines and observation for 6 to 28 hours of
intensive care monitoring. A safe therapy is necessary to halt the progression of symptoms
early in the clinical course while avoiding the clinical deterioration that can occur en
route to a tertiary facility. Alacramyn® is anticipated to be safer and more effective than
the present standard of care, midazolam, and faster-acting such that the need for transport
of most rural patients will be eliminated and will reduce hospitalization time.
The working hypotheses are as follows:
1. The investigational antivenom is safe as treatment of scorpion sting envenomation.
2. The investigational antivenom is effective as treatment of scorpion sting envenomation.
Official title: Prospective, Randomized, Double-Blind, Controlled Study of Alacramyn® vs. Placebo in Pediatric Patients With Systemic Signs of Scorpion Sting Envenomation
Study design: Treatment, Randomized, Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Placebo Control, Parallel Assignment, Efficacy Study
Primary outcome: The primary study endpoint is the resolution of clinically important signs of scorpion envenomation
AlacramynÂ®-treated patients require significantly less benzodiazepine sedation than placebo controls, for control of agitation
Venom blood levels decrease after AlacramynÂ® treatment, while the placebo group continues to have elevated blood venom levels
The purpose of this Prospective, Randomized, Double-Blind, Controlled, Multicenter Treatment
Protocol, phase III trial is to examine the safety and efficacy of AlacramynÂ® for treatment
of patients envenomed by scorpion sting.
This study will take place in two pediatric Intensive care units in Tucson, Arizona.
Patients who arrive at the emergency clinic presenting with scorpion sting symptoms will be
evaluated for treatment with respect to the inclusion/exclusion criteria according to the
study procedures. Only patients with clinically important systemic signs of scorpion sting
envenomation will be included in the study. Baseline measures will include severity
evaluation of the scorpion sting envenomation. The patient's vital signs, concomitant
medication, medical history and demographic data will be collected. Blood tests will be done
for haematology, chemistry, venom and anti-venom levels and urine test.
After informed consent and inclusion7exclusion criteria have been obtained and verified, and
the baseline measurements have been done, three vials of AlacramynÂ® or placebo will be
administered. During the following 3 hours, midazolam will continue, if indicated for
control of agitation.
Patients off midazolam sedation after receiving study drug and no longer manifesting
clinically important systemic signs of scorpion envenomation will be discharge at 4 hours, or
2 hours following cessation of midazolam drip, whichever occurs later. Prior to discharge
repeat lab work, physical assessments, and vital signs will be done. Patients still requiring
midazolam sedation and/or manifesting clinically important systemic signs of scorpion
envenomation will be treated with standard of care for the duration of clinical symptoms.
Those remaining for extended care undergo final study assessments at time of hospital
discharge or at 24 hours after study drug infusion if hospitalization continues.
All patients who participated in the study will be contacted 7 and 14 days after treatment,
looking for symptoms suggestive of ongoing venom effect, delayed serum sickness as well as
for any other adverse event reported by the patient.
Minimum age: 6 Months.
Maximum age: 18 Years.
- Males and females of 6 months to 18 years of age
- Presenting for emergency treatment within 5 hours with clinically important systemic
signs of scorpion sting envenomation.
- Signed written Informed Consent by patient or legal guardian.
- No participation in a clinical drug trial within the last month or concomitantly.
- Allergy to horse serum.
- Use within the past 24 hours of drugs expected to alter immune response: H1 or H2
- Use of any antivenom within the last month or concomitantly.
- Underlying medical conditions that significantly alter immune response: bone marrow
suppression congenital or acquired immuno-deficiency state, chemotherapy and chronic
- Allergy to midazolam.
- More than 0. 3mg/kg of body weight of midazolam administered during the hour prior to
study drug infusion.
- Concurrent medical condition involving a baseline neurologic status mimicking
envenomation (chorea, tardive dyskinesia, uncontrolled epilepsy).
- Pregnant and nursing women.
Locations and Contacts
Tucson Medical Center, Tucson, Arizona, United States
University Medical Center, Tucson, Arizona, United States
The University of Arizona
Instituto de Biotecnologia de la UNAM
Likes K, Banner W Jr, Chavez M. Centruroides exilicauda envenomation in Arizona. West J Med. 1984 Nov;141(5):634-7. No abstract available.
Gibly R, Williams M, Walter FG, McNally J, Conroy C, Berg RA. Continuous intravenous midazolam infusion for Centruroides exilicauda scorpion envenomation. Ann Emerg Med. 1999 Nov;34(5):620-5.
Curry SC, Vance MV, Ryan PJ, Kunkel DB, Northey WT. Envenomation by the scorpion Centruroides sculpturatus. J Toxicol Clin Toxicol. 1983-1984;21(4-5):417-49. Review.
LoVecchio F, Welch S, Klemens J, Curry SC, Thomas R. Incidence of immediate and delayed hypersensitivity to Centruroides antivenom. Ann Emerg Med. 1999 Nov;34(5):615-9.
Berg RA, Tarantino MD. Envenomation by the scorpion Centruroides exilicauda (C sculpturatus): severe and unusual manifestations. Pediatrics. 1991 Jun;87(6):930-3. No abstract available.
Rachesky IJ, Banner W Jr, Dansky J, Tong T. Treatments for Centruroides exilicauda envenomation. Am J Dis Child. 1984 Dec;138(12):1136-9.
Starting date: May 2004
Ending date: October 2005
Last updated: May 27, 2008