Intrapartum Sildenafil in Laboring Mothers

NCT06377098 | Withdrawn Phase 3

• 2 other identifiers: UAB-300010901UAB Dixon Endowed Ch/3102800
• Study Type: interventional
• Target: N/A
• Locations: 3 countries
• Sites: 3

Brief Summary

The goal of this feasibility pilot clinical trial is to learn if sildenafil citrate 50mg orally, up to three times during labor, can be appropriately administered, with limited clinical side effects, to laboring mothers to determine feasibility across a spectrum of available healthcare resources. The main questions it aims to answer are:

• What are the fetal heart rate monitoring practices in a low-resource setting?
• What are the indications for operative delivery in a low-resource?
• What is the rate of relevant primary and secondary outcomes to possibly target in a large RCT of intrapartum sildenafil?
• What is the limited effect size of sildenafil citrate on maternal and neonatal outcomes in a low-resource setting? Researchers will compare the administration of sildenafil citrate 50 mg orally to a placebo (a look-alike substance that contains no drug) to see if procedures are feasible, the drug is tolerated, the target outcomes are achievable, and effect size is as expected. Participants will:
• Take Sildenafil 50 mg/placebo every eight hours or a placebo every eight hours for up to 24 hours during labor
• Have the (mothers \& babies) medical charts reviewed for outcomes, including fetal distress, operative delivery, maternal side effects, neonatal bag \& mask ventilation, Apgar scores, and seizures.
• Have a neonatal neurological assessment prior to discharge
• Have phone call assessments for re-hospitalization or mortality 7 days post-delivery
• Receive child development assessments at 1 year, 2 years and 3 years of age by the Ages and Stages Questionnaire administered via a telephone call The results of this feasibility pilot trial will be used to inform the design and conduct of a large pragmatic randomized controlled trial to determine if sildenafil citrate, compared to placebo, will decrease fetal distress and perinatal asphyxia.

Conditions

Neonatal Asphyxia; Intrapartum Fetal Distress; Development, Infant; Intrapartum Asphyxia

Keywords

Sildenafil citrate

Outcome Measures

Primary Outcomes (3)

• Percentage of perinatal mortality

  Documentation of stillbirth or neonatal death

  96 hours after enrollment

• Percentage of operative delivery

  Documentation of type of delivery

  96 hours after enrollment

• Indication for operative delivery

  Documentation of type of delivery

  96 hours after enrollment

Secondary Outcomes (12)

• Percentage of mothers who received fetal heart rate monitoring

  96 hours after enrollment

• Indication for fetal heart rate monitoring

  96 hours after enrollment

• Apgar Score

  1 minute and 5 minutes after birth

• Percentage of use of bag and mask ventilation in neonates

  20 minutes after delivery

• Percentage of neonates with neonatal encephalopathy

  24 hours after birth

Study Arms (2)

Oral Sildenafil 50mg

ACTIVE COMPARATOR

Sildenafil citrate 50mg given orally every eight hours up to 3 doses while mother is in labor

Drug: Sildenafil 50 mg Oral Tablet

Placebo

PLACEBO COMPARATOR

Identical-appearing treatment that does not contain the test drug given orally every eight hours up to 3 doses while mother is in labor

Drug: Placebo Oral Tablet

Interventions

Sildenafil 50 mg Oral Tablet DRUG

Sildenafil 50 mg given orally every eight hours up to three times while mother is in labor

Also known as: Revatio, Sildenafil

Oral Sildenafil 50mg

Placebo Oral Tablet DRUG

Placebo table given orally every eight hours up to three times while mother is in labor

Placebo

Eligibility Criteria

• Age: 0 Days - 40 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Pregnant women presenting in early labor with a term pregnancy (≥ 37 weeks gestation)
• Early labor will be defined as cervical dilation less than or equal to 6 cm
• Gestational age will be calculated from the most reliable variable using the following hierarchy of reliability: 2) gestational dating ultrasound completed at any time during the pregnancy (with preference to the earliest exam); 2) date of last menstrual period if menses are regular.
• Planned vaginal delivery and admission to health facility with clear plan for spontaneous or induced vaginal delivery
• Maternal age ≥ 18yrs or minors 14-17yrs eligible in countries where married or pregnant minors or their authorized representatives are legally permitted to give consent
• A single, live fetus in cephalic presentation confirmed prior to randomization

You may not qualify if:

• Unknown gestational age
• Maternal history of cesarean delivery
• Advanced stage of labor (\>6 cm or 10 cm cervical dilation per local standards) and pushing, or too distressed to understand, confirm, or give informed consent regardless of cervical dilation
• Not capable of giving consent due to other health problems, such as obstetric emergencies (i.e. antepartum hemorrhage) or mental disorder
• Maternal contraindication to sildenafil therapy, such as hypersensitivity to nitrates or nitrites
• Any medical condition considered a contraindication per the judgement of site investigators
• Recognized fetal anomaly
• Any maternal medical condition or status that precludes informed consent
• Non-emancipated minors (as per local regulations
• Plan for cesarean delivery prior to enrollment
• Previous randomization in the trial

Sponsors & Collaborators

• University of Alabama at Birmingham: lead
• University Teaching Hospital, Lusaka, Zambia: collaborator
• Egerton University: collaborator
• Cameroon Baptist Convention Health: collaborator

Study Sites (3)

Cameroon Baptist Convention Health Services

Douala, Cameroon

Location

Egerton University/Nakuru County Referral Hospital

Nakuru, Kenya

Location

University Teaching Hospital

Lusaka, Zambia

Location

MeSH Terms

Conditions

Asphyxia Neonatorum

Interventions

Sildenafil Citrate; Tablets

Condition Hierarchy (Ancestors)

Infant, Newborn, Diseases; Congenital, Hereditary, and Neonatal Diseases and Abnormalities

Intervention Hierarchy (Ancestors)

Sulfonamides; Amides; Organic Chemicals; Sulfones; Sulfur Compounds; Piperazines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Purines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Dosage Forms; Pharmaceutical Preparations

Study Officials

• Waldemar A Carlo, MD

  University of Alabama at Birmingham

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: The only person who will be unmasked will be the pharmacist who will dispense the study medication--either sildenafil 50mg or identical placebo
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Edwin M. Dixon Professor of Pediatrics

Model Details: Double blinded, placebo-controlled, 1:1 parallel allocation, randomized feasibility trial

Study Record Dates

• First Submitted: April 12, 2024
• First Posted: April 22, 2024
• Study Start: May 1, 2025
• Primary Completion (Estimated): August 31, 2026
• Study Completion (Estimated): September 30, 2028
• Last Updated: September 16, 2025

Record last verified: 2025-09

Locations

CA (1); ZA (1); KE (1)