Doxycycline vs. Macrolide for MRMP (DOMINO)

Young June Choe

Status and phase: Begins enrollment this month; Phase 4

Conditions: Mycoplasma Pneumoniae Pneumonia; Mycoplasma Pneumoniae

Treatments: Drug: Doxycycline; Drug: Azithromycin

Study type: Interventional

Funder types: Other

Identifiers

NCT07306234

KNIH (Other Grant/Funding Number)

DOMINO

Details and patient eligibility

About

The goal of this clinical trial is to learn if doxycycline works to treat pneumonia in children. It focuses on children with Mycoplasma pneumoniae infection that may not respond to standard medicines. The main questions it aims to answer are:

• Does doxycycline stop fevers faster than azithromycin?
• Is doxycycline safe for children, specifically regarding tooth color changes?

Researchers will compare doxycycline to azithromycin to see if doxycycline works better to treat this type of pneumonia.

Participants will:

• Take either doxycycline or azithromycin by mouth for 7 to 14 days.
• Check their body temperature to see when their fever goes away.
• Visit the hospital to check for any medical problems.
• Have their teeth checked for color changes 28 days after starting the medicine.

Enrollment: 208 estimated patients

Sex: All

Ages: 3 to 17 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age: 3 to 17 years at the time of enrollment.
• Diagnosis: Clinically diagnosed CAP characterized by respiratory symptoms (e.g., fever, cough, auscultatory findings) and chest X-ray confirming pulmonary infiltrates.
• Pathogen: Confirmed MP M. pneumoniae infection via PCR OR strongly suspected infection based on clinical features and epidemiological grounds (e.g., outbreaks among classmates, poor response to prior non-macrolide antibiotics).
• Resistance: Suspected macrolide-resistant M. pneumoniae (MRMP) infection (e.g., during a reported local epidemic of MRMP).
• Timing: Ability to register and initiate the study drug within 72 hours of symptom onset.

Exclusion criteria

• Prior use of tetracyclines, macrolides, or quinolones for the current illness.
• Complicated pneumonia (e.g., necrosis, empyema, lung abscess) or severe pneumonia requiring immediate intensive care or exhibiting hypoxia (SpO₂ <90%).
• Hypersensitivity or contraindications to macrolides or tetracyclines.
• Severe immunocompromised state or severe underlying lung disease.
• Severe hepatic impairment (AST/ALT >3x upper limits) or severe renal impairment.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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208 participants in 2 patient groups

Intervention Group (Doxycycline)

Experimental group

Description:

Participants will receive oral doxycycline (4 mg/kg/day divided into 2 doses for weight ≤45 kg; 100 mg BID for weight \>45 kg). The standard treatment duration is 7 days, which may be extended up to 14 days based on clinical response.

Treatment:

Drug: Doxycycline

Control Group (Azithromycin)

Active Comparator group

Description:

Participants will receive oral azithromycin according to the standard 5-day regimen (10 mg/kg on Day 1, followed by 5 mg/kg on Days 2-5).

Treatment:

Drug: Azithromycin