A Multicenter, Randomized, Double-Blind, Double-Dummy Comparative Trial of Azithromycin Sustained Release Versus 3-Day Azithromycin for the Treatment of Strep Throat in Adolescents and Adults

This study has been completed.
Information provided by:
ClinicalTrials.gov Identifier:
First received: March 19, 2008
Last updated: June 3, 2011
Last verified: June 2011

To determine if a single 2.0-g dose of azithromycin SR is at least as effective as a 3-day course of azithromycin (500 mg once daily for 3 days) when used to treat adolescents and adults with strep throat, and to assess efficacy and safety for both treatment regimens.

Condition Intervention Phase
Drug: azithromycin (Zithromax)
Drug: placebo
Drug: azithromycin SR
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
Official Title: A Multicenter, Randomized, Double-Blind, Double-Dummy Comparative Trial of Azithromycin SR Versus Three-Day Azithromycin for the Treatment of Group A β-Hemolytic Streptococcal Pharyngitis/Tonsillitis in Adolescents and Adults

Resource links provided by NLM:

Further study details as provided by Pfizer:

Primary Outcome Measures:
  • bacteriologic response in the Bacteriologic per Protocol population [ Time Frame: Test of Cure (TOC) visit (Days 24-28) ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • sponsor assessment of clinical response in the Bacteriologic per Protocol population [ Time Frame: TOC visit ] [ Designated as safety issue: No ]
  • bacteriologic response for the remaining study populations [ Time Frame: TOC visit ] [ Designated as safety issue: No ]
  • sponsor assessment of clinical response for the Bacteriologic per Protocol population [ Time Frame: Long-Term Follow-Up (LTFU) visit (Days 38-45) ] [ Designated as safety issue: No ]
  • bacteriologic response for the Bacteriologic per Protocol population [ Time Frame: TOC visit ] [ Designated as safety issue: No ]
  • summary of baseline susceptibilities [ Time Frame: Study endpoint ] [ Designated as safety issue: No ]
  • adverse events [ Time Frame: Continuous ] [ Designated as safety issue: Yes ]

Enrollment: 598
Study Start Date: January 2003
Study Completion Date: April 2004
Arms Assigned Interventions
Experimental: 1 Drug: azithromycin (Zithromax)
azithromycin 500 mg tablet by mouth once daily for 3 days
Drug: placebo
Experimental: 2 Drug: azithromycin SR
azithromycin SR 2.0 g by mouth as an oral slurry for 1 dose
Drug: placebo


Ages Eligible for Study:   13 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Patients with evidence of acute group A beta-hemolytic streptococcus (GABHS) pharyngitis/tonsillitis and a positive rapid antigen detection test or positive culture of the pharynx or tonsils for GABHS

Exclusion Criteria:

  • Patients were excluded if they had treatment with any systemic antibiotic within the previous 7 days, a history of rheumatic fever, a peritonsillar abcess, or were known carriers of GABHS.
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00644293

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Sponsors and Collaborators
Study Director: Pfizer CT.gov Call Center Pfizer
  More Information

Additional Information:
No publications provided

Responsible Party: Director, Clinical Trial Group, Pfizer, Inc.
ClinicalTrials.gov Identifier: NCT00644293     History of Changes
Other Study ID Numbers: A0661119
Study First Received: March 19, 2008
Last Updated: June 3, 2011
Health Authority: United States: Food and Drug Administration

Additional relevant MeSH terms:
Pharyngeal Diseases
Stomatognathic Diseases
Respiratory Tract Infections
Respiratory Tract Diseases
Otorhinolaryngologic Diseases
Anti-Bacterial Agents
Anti-Infective Agents
Therapeutic Uses
Pharmacologic Actions

ClinicalTrials.gov processed this record on April 17, 2014