Oxytocin Pharmacokinetics and Pharmacodynamics
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: deuterated oxytocin (d5OT).
- Who it may be relevant to
- Registry conditions: Post Partum Hemorrhage, Cesarean Section Complications, Blood Loss. Basic parameters: 18 years — 50 years · Female.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Pharmacokinetics and Pharmacodynamics of Oxytocin in Cesarean Delivery
Overview
Oxytocin is the first-line drug to promote contraction of the uterus and prevent atony immediately after delivery. Nonetheless, unpredictable uterine atony refractory to oxytocin affects roughly 250,000 parturients annually in the U.S. and rates are increasing. This two-part study will measure the action of oxytocin at cesarean delivery. The first part will measure the pharmacokinetics of a single intravenous (IV) dose of deuterium-labeled oxytocin. The second part will measure the pharmacodynamics of all plasma oxytocin to see how concentrations correspond to the contractile effect on the uterus. After delivery of the fetus, study subjects will receive a bolus of IV deuterated oxytocin followed by an unlabeled oxytocin infusion. Venous blood samples drawn at multiple time points (within 1 hour after delivery) will be analyzed for plasma concentrations of labeled and unlabeled (endogenous + exogenous infused) oxytocin over time. Plasma concentrations will be compared with 0-10 uterine tone scores measuring uterine contraction strength, to describe the concentration-effect relationship. The goal of this study is to define both the pharmacokinetics and pharmacodynamics of oxytocin in parturients to help identify the cause(s) of failed first-line oxytocin therapy.
Detailed description
Parturients aged 18-50 with an intrauterine term pregnancy (37 weeks or greater) undergoing non-emergent cesarean delivery at the University of Chicago (UC) and Stanford University will be recruited.
Methods: All subjects will receive standard pre-, intra- and postoperative care for their cesarean delivery with additional study interventions.
Study subjects will have an additional intravenous (IV) catheter inserted for intra-operative study-related blood draws.
A single, 1 International Unit (IU) bolus of deuterated oxytocin (d5OT) will be given to the subject, followed by an infusion of standard protocol oxytocin immediately after placental delivery. IV samples will be drawn from the study IV at 0, 1, 2.5, 5, 10, 20, 30, 45, 60 minutes following administration of the study drug. The samples will be processed, batched and shipped to the central lab being used in this study. Uterine tone scores will be measured simultaneously with blood draws until accurate palpation is no longer possible. Uterine tone score is a 0 to 10 numeric rating scale with 0 to describe unsatisfactory or no uterine tone and 10 to describe perfect uterine tone.
Interventions
- Drug deuterated oxytocin (d5OT)
Subjects will receive a 1 IU bolus of deuterated oxytocin (d5OT) intraoperatively during their nonemergent cesarean delivery.
Primary outcome measures
- Baseline plasma concentrations of deuterated oxytocin [Time frame: Intraoperatively (prior to delivery)]
- Plasma concentrations of deuterated oxytocin at 1 minute [Time frame: Intraoperatively (1 minute following study drug administration)]
- Plasma concentrations of deuterated oxytocin at 2.5 minutes [Time frame: Intraoperatively (2.5 minutes following study drug administration)]
- Plasma concentrations of deuterated oxytocin at 5 minutes [Time frame: Intraoperatively (5 minutes following study drug administration)]
- Plasma concentrations of deuterated oxytocin at 10 minutes [Time frame: Intraoperatively (10 minutes following study drug administration)]
- Plasma concentrations of deuterated oxytocin at 15 minutes [Time frame: Intraoperatively (15 minutes following study drug administration)]
- Plasma concentrations of deuterated oxytocin at 20 minutes [Time frame: Intraoperatively (20 minutes following study drug administration)]
- Plasma concentrations of deuterated oxytocin at 30 minutes [Time frame: Intraoperatively (30 minutes following study drug administration)]
- Plasma concentrations of deuterated oxytocin at 45 minutes [Time frame: Intraoperatively (45 minutes following study drug administration)]
- Plasma concentrations of deuterated oxytocin at 60 minutes [Time frame: Intraoperatively (60 minutes following study drug administration)]
Eligibility criteria
Inclusion criteria
- 18-50 years old
- intrauterine pregnancy
- term (>39 weeks gestation or 37-39 weeks gestation with fetal or maternal medical indication for delivery) pregnancy
- non-emergent (scheduled or unscheduled) cesarean delivery
Exclusion criteria
- allergy or contraindication to oxytocin
- inability to provide informed consent
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- N/A
- Model
- Single group
- Masking
- Open label
- Primary purpose
- Prevention
Study locations
United States · 2 centers
- Stanford University — Stanford
- University of Chicago — Chicago
Identifiers
NCT: NCT05488457 · IRB24-0480