Cellulitis Optimal Antibiotic Treatment (COAT)

University of Southampton

Status and phase: Enrolling; Phase 3

Conditions: Cellulitis of Leg

Treatments: Drug: Flucloxacillin Only Product in Oral Dose Form; Drug: Placebo Only Product in Oral Dose Form

Study type: Interventional

Funder types: Other

Identifiers

NCT05584007

ERGO 67073

Details and patient eligibility

About

To determine whether a short course of oral flucloxacillin (5 days) is non-inferior to a standard course (7 days) in terms of pain over days 6-14 (indicative of persistence or recurrence associated with the symptoms of most importance to patients) in adults with cellulitis of the leg presenting in primary care.

Full description

Cellulitis is a deep infection of the skin and subcutaneous tissues and most often occurs in the legs. It is a painful condition that is associated with inflammation and swelling of the site, and often systemic symptoms such as fever, headache, muscle aches, malaise, and fatigue. Patients report feeling unwell and that it has a significant impact on their mobility and ability to carry out their usual activities. NICE guidelines recommend oral flucloxacillin 500-1000 mg four times daily for 5-7 days as first-line treatment for most patients with cellulitis in the community, but most prescriptions are dispensed for a 7-day course. We will be assessing the effectiveness and safety of a 5-day treatment vs. the standard 7-day treatment. We also aim to evaluate the cost-consequences of a shorter course from an NHS and personal perspective. Participants will be randomly allocated to one of two groups. In addition to usual care, participants will either be assigned to a 5-day oral flucloxacillin course or a standard 7-day flucloxacillin course. Participants will be prescribed a 5-day course of oral flucloxacillin, and two additional tablets will be posted to the participants which will either be the antibiotic or a placebo tablet. Participants will be asked to fill out daily questionnaires and express their experiences with the shortened course and taking part in the trial.

Enrollment: 356 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Must be aged 18 years or older
• Currently showing symptoms of cellulitis (such as pain, tenderness, redness, other change in skin color, warmth to touch) in one leg for 10 days or less
• Pain rated as 3/10 or higher on a numerical rating scale (0-10) at baseline assessment
• Be willing to be randomized to either trial arm (5-day or 7-day treatment)
• Able to complete trial procedures in the English language.

Exclusion criteria

• Have penicillin allergy
• Have bilateral cellulitis
• Have had antibiotics for cellulitis within the past month
• Have post-operative cellulitis (within 30 days of operative procedures on the same leg)
• Have cellulitis resulting from human/animal bite injury
• Have Cellulitis associated with chronic (>6 weeks) leg ulceration
• Require immediate hospital admission or out-patient intravenous antibiotic therapy

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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356 participants in 2 patient groups, including a placebo group

Intervention

Placebo Comparator group

Description:

Flucloxacillin 500mg four times a day (QDS) for 5 days (unblinded NHS prescription) followed by blinded placebo QDS for 2 days (5 days of antibiotic)

Treatment:

Drug: Placebo Only Product in Oral Dose Form

Drug: Flucloxacillin Only Product in Oral Dose Form

Control

Active Comparator group

Description:

Flucloxacillin 500mg QDS for 5 days (unblinded NHS prescription) followed by flucloxacillin 500mg QDS (blinded) for 2 days (7 days of antibiotic)

Treatment:

Drug: Flucloxacillin Only Product in Oral Dose Form