A Phase 3 interventional study of Azithromycin Injection and Placebo in Obstetrical Complications, Labor and Delivery Complication and Cesarean Delivery, sponsored by The George Washington University Biostatistics Center. Recruiting at 14 sites in United States. Open to female participants, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-04-09.
Sponsored by The George Washington University Biostatistics Center · Phase 3, Interventional, and Prevention
Help build ClinicalTrials.gg — short surveys, remote interviews or testing, in your language. Take part →
This is a phase-III multi-center double-blind randomized controlled trial of 8,000 individuals undergoing a scheduled or prelabor cesarean delivery who are randomized to either adjunctive azithromycin prophylaxis or to placebo. Both groups also will receive standard of care preoperative antibiotics (excluding azithromycin). The primary endpoint is a maternal infection composite defined as any one of the following up to 6 weeks postpartum: endometritis, wound infection, abscess, septic thrombosis, sepsis, pneumonia, pyelonephritis and breast infection.
This is a phase-III multi-center double-blind randomized controlled trial of 8,000 individuals undergoing a scheduled or prelabor cesarean delivery who are randomized to either azithromycin prophylaxis or to placebo. All participants will receive standard of care preoperative antibiotics. The primary objective is to evaluate in patients undergoing scheduled/prelabor cesarean if pre-incision adjunctive azithromycin prophylaxis reduces the risk of post-cesarean infections compared with placebo. Secondary objectives include 1) to assess the perinatal and maternal safety of pre-incision adjunctive azithromycin, 2) to evaluate whether adjunctive azithromycin prophylaxis reduces maternal and neonatal resource use outcomes compared with placebo, and 3) to evaluate whether adjunctive azithromycin influences maternal and neonatal infection with resistant organisms compared with placebo.
Individuals will be randomized prior to the start of the cesarean to either 500mg of intravenous azithromycin or to placebo (normal saline). Maternal blood and cord blood will be collected on a subset of the population. Research staff will abstract maternal and neonatal outcomes following delivery and discharge from the hospital. A single maternal follow-up study visit at 6 weeks (4-8 weeks) postpartum will be scheduled to ascertain maternal and neonatal outcomes.
2,094 studies on the registry are indexed under Infections; 364 are open to participants now.
This study's planned enrollment of 8,000 is above the median of 113 across 1,304 interventional studies indexed under Infections.
Browse Infections studies →The George Washington University Biostatistics Center is the lead sponsor of 25 studies on the registry; 3 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 6 (100%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
500mg of intravenous azithromycin administered up to 1 hour prior to cesarean incision (or as soon as feasible after incision) and infused over one hour per FDA infusion recommendations for azithromycin. Additionally patients will received standard of care preoperative antibiotics (excluding azithromycin) prior to incision.
Drug: Azithromycin Injection · Drug: Standard of Care Preoperative antibiotics
Normal saline administered up to 1 hour prior to cesarean incision (or as soon as feasible after incision) and infused over one hour in addition to standard of care preoperative antibiotics (excluding azithromycin) prior to incision.
Drug: Placebo · Drug: Standard of Care Preoperative antibiotics
500mg azithromycin in 250 mL of normal saline
250 mL of normal saline
standard of care preoperative antibiotics (excluding azithromycin) prior to incision
Maternal infection composite
a maternal infection composite defined as any one of the following: endometritis, wound infection, abdominal or pelvic abscess, septic pelvic thrombosis, sepsis, pneumonia, pyelonephritis and breast infection
Time frame: Delivery up to 6 weeks postpartum (a period of up to 6 weeks)
Non-infections wound complications
any of the following wound complications without diagnosis of a wound infection: seroma, wound breakdown, erythema and/or hematoma
Time frame: Delivery up to 6 weeks postpartum (a period of up to 6 weeks)
Perinatal composite outcome
Any of the following: * Neonatal death occurring within 28 days of birth or prior to initial discharge from hospital * Respiratory distress syndrome * Necrotizing enterocolitis grade 2 or higher * Periventricular leucomalacia * Intraventricular hemorrhage grades 3 or 4 * Bronchopulmonary dysplasia grade 3 or higher * Suspected sepsis * Confirmed sepsis * Cardiac resuscitation * Severe neonatal drug reaction defined as anaphylaxis or any other reported severe event suspected to be due to azithromycin * Hypertrophic pyloric stenosis defined as physician diagnosis supported by surgical intervention (pyloromyotomy) or pathology evaluation through 6 weeks from birth.
Time frame: hospital discharge, 6 weeks of birth, or death (whichever occurs first)
Number of neonates with Allergic Reaction
Neonatal allergic reaction (e.g., skin rash) through discharge or 7 days from birth, whichever is earliest, suspected to be due to study medication.
Time frame: birth through hospital discharge, or 7 days from birth, whichever is earliest
Number of Neonates with Gastrointestinal Symptoms
vomiting, diarrhea, feeding difficulty through discharge or 7 days from birth, whichever is earliest
Time frame: birth through hospital discharge, or 7 days from birth, whichever is earliest
Number of Maternal Deaths
Death
Time frame: From randomization through 6 weeks postpartum (a period of up to 6 weeks)
Maternal Resource Composite
* Hospital readmission * Emergency room (ER) visit * Unscheduled clinic visits
Time frame: From hospital discharge following delivery through 6 weeks postpartum (a period of up to 6 weeks)
Neonatal Resource Composite
* Hospital readmission * Emergency Room (ER) visit
Time frame: From hospital discharge following delivery through 6 weeks postpartum (a period of up to 6 weeks)
Maternal Hospital Length of Stay
Length of hospital stay in days
Time frame: Hospital admission to hospital discharge (up to 42 days)
Rate of Neonatal ICU Admission
Number of neonates admitted to NICU
Time frame: Delivery to hospital discharge (up to 120 days)
Number of Participants with Maternal Resistant Infection
bacteria and resistance patterns from clinical cultures
Time frame: Randomization through 6 weeks postpartum (a period of up to 6 weeks)
Number of Neonates with Neonatal Resistant Infection
bacteria and resistance patterns from clinical cultures
Time frame: From birth up to 6 weeks of age
Plan to share: Yes — Data will be shared via NICHD DASH in accordance with NIH policy.
Supporting information: Study protocol, Informed consent form
No publications or documents are linked to this record.
Started Nov 2024 (actual). Primary completion is estimated for Nov 2027, 36 months after the start.
Of 75 phase 3 interventional studies under Infections, half reached primary completion within 30 months of starting (the median), counting those still running; a quarter within 17 and three quarters within 53. This study's planned 36 months is above that.
Infections covers many different conditions, not one, so the studies compared here vary widely. Read these figures as a rough guide.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Azithromycin
The George Washington University Biostatistics Center