Confirmatory Study of 17P vs Vehicle for Prevention of Preterm Birth in Women w/ Previous Spontaneous Preterm Delivery (PROLONG)
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ClinicalTrials.gov Identifier: NCT01004029 |
Recruitment Status :
Completed
First Posted : October 29, 2009
Results First Posted : January 28, 2021
Last Update Posted : June 1, 2022
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Condition or disease | Intervention/treatment | Phase |
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Preterm Birth | Drug: Hydroxyprogesterone Caproate Injection (HPC), 250mg/mL Drug: Vehicle | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 1740 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) |
Primary Purpose: | Prevention |
Official Title: | A Phase 3B, Multi-Center, Randomized, Double-Blind Study of Hydroxyprogesterone Caproate (HPC) Injection, 250 mg/mL, Versus Vehicle for the Prevention of Preterm Birth in Women With a Previous Singleton Spontaneous Preterm Delivery |
Actual Study Start Date : | October 2009 |
Actual Primary Completion Date : | October 2018 |
Actual Study Completion Date : | October 2018 |
Arm | Intervention/treatment |
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Placebo Comparator: Vehicle
Castor Oil
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Drug: Vehicle
Weekly intramuscular injections of 1 mL vehicle inert oil until 36 weeks, 6 days of gestation or delivery, whichever occurs first.
Other Name: Placebo |
Active Comparator: Hydroxyprogesterone Caproate Injection (HPC), 250 mg/mL
HPC 250 mg/mL in oil
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Drug: Hydroxyprogesterone Caproate Injection (HPC), 250mg/mL
1 mL intramuscular injection every week until 36 weeks, 6 days of gestation or delivery, whichever occurs first.
Other Names:
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- Preterm Birth <35 Weeks Gestation [ Time Frame: Up to 35 weeks ]Determine if treatment with 17P reduces the rate of preterm birth < 35 weeks, 0 days of gestation in women with a previous singleton spontaneous preterm delivery.
- Neonatal Composite Index (NCI) [ Time Frame: Until 28 days of life or discharge from the neonatal intensive care unit (NICU), whichever occurred later. ]The composite index is defined as a liveborn neonate with any of the following occurring at any time during the birth hospitalization up through discharge from the NICU: neonatal death, grade 3 or 4 intraventricular hemorrhage, respiratory distress syndrome, bronchopulmonary dysplasia, necrotizing enterocolitis or proven sepsis.
- Fetal/Early Infant Death [ Time Frame: Delivery from 16 weeks 0 days through 19 weeks 6 days of gestation; or neonatal death occurring in liveborns born at less than 24 weeks gestation; or stillbirth (antepartum or intrapartum death) from 20 weeks gestation through term). ]Defined as spontaneous abortion/miscarriage (delivery from 16 weeks 0 days through 19 weeks 6 days of gestation) or neonatal death occurring in liveborns born at less than 24 weeks gestation or stillbirth (antepartum or intrapartum death from 20 weeks gestation through term), in the 17P group compared to the vehicle group
- Preterm Birth Prior to 32 Weeks Gestation [ Time Frame: Up to 32 weeks ]
- Preterm Birth Prior to 37 Weeks Gestation [ Time Frame: Up to 37 weeks ]
- Stillbirths [ Time Frame: 20 weeks gestation until term ]Defined as all stillbirths/fetal deaths/in utero fetal losses occurring from 20 weeks gestation until term.
- Neonatal Deaths With ≥24 Weeks Gestational Age [ Time Frame: Until 28 days of life or discharge from the NICU whichever occurred later. ]Neonatal death (from minutes after birth until 28 days of life) occurring in liveborns born at 24 weeks gestation or greater

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | Female |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
Each subject must meet the following criteria to be enrolled in this study:
- Age ≥ 18 years.
- Singleton gestation.
- Project gestational age 16 weeks 0 days of gestation or more and less than or equal to 20 weeks 6 days of gestation at the time of randomization, based on clinical information and evaluation of the first ultrasound.
- Documented history of a previous singleton spontaneous preterm delivery. Spontaneous preterm birth is defined as delivery from 20 weeks 0 days to 36 weeks 6 days of gestation following spontaneous preterm labor or pPROM. Where possible, the gestational age of the previous preterm birth (referred to as the qualifying delivery) should be determined as described in "Gestational Age Determination". If the gestational age at delivery is obtained directly from the medical record and more than one gestational age appears, the latest will be used. As a validation of the gestational age of the previous delivery, if the infant weighed more than 3300 grams (the birth weight 90th percentile for 36 weeks gestational age), this will not qualify as preterm. The previous preterm delivery cannot be an antepartum stillbirth.
Exclusion Criteria:
- Multifetal gestation.
- Known major fetal anomaly or fetal demise. An ultrasound examination between 14 weeks 0 days through 20 weeks 3 days of gestation must be performed to rule out fetal anomalies.
- Progesterone treatment in any form (i.e., vaginal, oral, intramuscular) during current pregnancy, other than micronized progesterone delivered orally or vaginally provided it is stopped at least 4 weeks prior to the first dose of study medication.
- Heparin therapy during current pregnancy or history of thromboembolic disease.
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Maternal medical/obstetrical complications including:
- Current or planned cerclage
- Hypertension requiring medication
- Seizure disorder
- Subjects with a uterine anomaly (uterine didelphys or bicornate uterus). However, subjects with uterine fibroids are eligible for the study.
- Unwillingness to comply with and complete the study.
- A 14 weeks 0 days through 20 weeks 3 days of gestation ultrasound cannot be arranged before randomization.
- Participation in an antenatal study in which the clinical status or intervention may influence gestational age at delivery.
- Participation in this trial in a previous pregnancy. Women who were screened in a previous pregnancy, but not randomized, do not have to be excluded.
- Known hypersensitivity to hydroxyprogesterone caproate or its components.
- Have any significant medical disorder that, in the opinion of the investigator, would be a contraindication to the use of the drug including those listed in section 5.3.2 of the investigational brochure. Other examples to consider include uncontrolled diabetes, known HIV infection or renal dysfunction.
- Have any significant medical disorder that, in the opinion of the investigator, would preclude accurate evaluation of the subject's condition or outcome in the study.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01004029

Documents provided by AMAG Pharmaceuticals, Inc.:
Responsible Party: | AMAG Pharmaceuticals, Inc. |
ClinicalTrials.gov Identifier: | NCT01004029 |
Other Study ID Numbers: |
17P-ES-003 |
First Posted: | October 29, 2009 Key Record Dates |
Results First Posted: | January 28, 2021 |
Last Update Posted: | June 1, 2022 |
Last Verified: | May 2022 |
17P 17-HPC 17-OHPC 17-hydroxyprogesterone caproate |
progestogens preterm birth recurrent preterm birth spontaneous preterm birth |
Premature Birth Obstetric Labor, Premature Obstetric Labor Complications Pregnancy Complications 17 alpha-Hydroxyprogesterone Caproate 11-hydroxyprogesterone |
Estrogen Antagonists Hormone Antagonists Hormones, Hormone Substitutes, and Hormone Antagonists Physiological Effects of Drugs Progestins Hormones |