High-dose vs. Standard-dose Cephalexin for Cellulitis

• Status: Recruiting
• Trial end date: 2022-06-01
• Target enrollment: 0
• Participant gender: All

Summary

Background: Cellulitis is a common clinical condition that represents up to 3% of all emergency department (ED) visits. The current treatment failure rate is approximately 20%. This high treatment failure rate may be due to suboptimal dosing of cephalexin. The Investigators hypothesize that high-dose cephalexin may lead to lower rates of treatment failure and subsequently improved patient outcomes (less hospitalizations and avoidance of intravenous antibiotics)

Rationale: Before embarking on a large, multicenter trial, it is essential to conduct a smaller pilot to test and refine study procedures and to demonstrate feasibility.

Methods:

Design: The investigators will conduct a parallel arm double-blind randomized controlled pilot trial at the Civic and General campus ED of The Ottawa Hospital (TOH). The study will operate seven days a week from 0800 to 2000 over a 6-month timeframe. TOH Pharmacy will follow a randomization sequence and prepare study medication packages. Study medication packages will be dispensed to the patient by a registered nurse (RN).

Patients: Adult (age >=18 years) ED patient with non-purulent cellulitis determined by the treating emergency physician to be eligible for outpatient care with oral antibiotics.

Intervention: High-dose cephalexin (1000 mg PO QID) for seven days.

Comparator: Standard-dose cephalexin (500 mg PO QID) plus placebo for seven days.

Primary Feasibility Outcome: Patient recruitment rate (percentage of approached eligible patients who are successfully recruited). The goal is to recruit at least 29% of eligible patients.

Primary Effectiveness Outcome: 1. Oral antibiotic treatment failure, defined as a change in antibiotic (change in class of oral antibiotic or step up to intravenous therapy) within 7 days due to worsening infection, which is defined as:

1. New fever (temperature ≥ 38.0C) or persistent fever at Day 3 follow up; or

2. Increasing area of erythema ≥20% from baseline; or

3. Increasing pain ≥2 points from baseline (numeric rating scale)

The secondary effectiveness outcomes are:

1. Clinical cure (no erythema, pain and fever) at day 7

2. Clinical response (≥20% reduction in area of erythema compared to baseline) at day 3

3. Adverse events (e.g. vomiting, diarrhea, rash) at 14-day telephone follow-up

4. Unplanned i) return ED visits; and ii) hospitalization at 14-day telephone follow-up

Importance: This pilot trial will be the first to compare high-dose cephalexin to standard-dose cephalexin for ED patients with cellulitis. The results of this pilot randomized trial will help inform the design and implementation of a larger, multicenter randomized controlled trial to answer this important clinical question.

• Phase: Phase 4
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Ottawa Hospital Research Institute
• Collaborators: Canadian Association of Emergency Physicians; The Ottawa Hospital Academic Medical Association
• Treatments: Cephalexin

Criteria

Inclusion Criteria:

Adults (age >=18 years) with non-purulent cellulitis determined by the treating emergency physician to be eligible for outpatient care with oral antibiotics.

Exclusion Criteria:

1. Age <18 years

2. Patient already taking oral antibiotics

3. Treating physician decides that intravenous therapy is required

4. Abscess requiring an incision and drainage or needle aspiration procedure

5. Known prior cellulitis secondary to methicillin-resistant Staphylococcus aureus

6. Cellulitis secondary to a human or animal bite wound

7. Surgical site infection

8. Malignancy and currently being treated with chemotherapy

9. Febrile neutropenia (temperature >=38C plus absolute neutrophil count <500 cells/uL)

10. Solid organ or bone marrow transplant recipient

11. Renal impairment with creatinine clearance <30 mL/min

12. Pregnant or breastfeeding

13. Allergy to cephalosporins or history of anaphylaxis to penicillin

14. Inability to provide consent