A Randomized, Open-Label, Controlled, Multi-Center Study on the Efficacy of a Sustained Release Progesterone Cerclage Cervical Pessary at Doses of 6.3 g or 7.7 g for the Prevention of Preterm Birth and a Maximum Duration of 20 Weeks.
Phase: PHASE2
Conditions: Preterm Birth
Sponsor: Grünenthal GmbH

A Randomized, Open-Label, Controlled, Multi-Center Study on the 
Efficacy of a Sustained Release Progesterone Cerclage Cervical 
Pessary at Doses of 6.3 g or 7.7 g for the Prevention of Preterm Birth 
and a Maximum Duration of 20 Weeks. 
 
NCT Number: 02225353 
Protocol ID: EC12012/10IEI-9339 
Date of Document:  16 May 2016 
 
 

Version 3 -May 16, 2016
Clinical Protocol: PCP 002
A Randomized, Open-Label, Controlled, Multi-Center Study on the 
Efficacy of a Sustained Release Progesterone Cerclage Cervical 
Pessary at Doses of 6.3 g or 7.7 g for the Prevention of Preterm Birth 
and a Maximum Duration of 20 Weeks
Research Sites:
Instituto de Investigación Materno Infantil (IDIMI) –Maternidad Hospital Clínico 
San Borja Arriarán (HCSBA).
UNICERH, South Department of Obstetrics & Gynecology –School of Medicine
UCHHospital Barros Luco-Trudeau.
Centro de Investigación e Innovación en Medicina Materno Fetal (CIMAF) -
Complejo Asistencial Dr. Sótero del Río (CASR)
East Department of Obstetrics & Gynecology –School of Medicine UCH Hospital 
Dr. Luis Tisné Brousse.
Study Phase: II
Sponsor:
Laboratorio Andrómaco S.A.
Avenida Quilín N° 5273, Peñalolén, Santiago

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SYNOPSIS
Protocol Number
PCP 002
Title
A Randomized, Open-Label, Controlled, Multi-Center Study on 
the Efficacy of a Sustained Release Progesterone Cerclage 
Cervical Pessary at Doses of 6.3 g or 7.7 g for the Prevention of 
Preterm Birth and a Maximum Duration of 20 Weeks
Sponsor and Phase
Andrómaco -Phase II
Type of Investigation 
Medical Device
Type of Study
Interventional
Study location
1. Instituto de Investigación Materno Infantil (IDIMI) –
Maternidad Hospital Clínico San Borja Arriarán (HCSBA).
2. UNICERH, South Department of Obstetrics &Gynecology –
School of Medicine UCHHospital Barros Luco
3. Centro de Investigación e Innovación en Medicina Materno 
Fetal (CIMAF) -Complejo Asistencial Dr. Sótero del Río (CASR).
4. East Department of Obstetrics & Gynecology –School of 
Medicine UCH Hospital Dr. Luis Tisné Brousse.
Primary Objective of 
the Study
To assess the efficacy of Cerclage Pessaries containing 6.3 g or 
7.7g of micronized progesterone for the Prevention of Preterm 
Birth, established through spontaneous parturition before 
gestation weeks 32 (31 6/7) and 34 (33 6/7), when the pessary is 
inserted between weeks 16 and 24 and removed at 36 6/7 weeks 
of gestation in pregnant women at risk of preterm birth.
Secondary Objectives of 
the Study
To record the occurrence of premature rupture of membranes 
before gestation weeks 32 (31 6/7) and 34 (33 6/7).
To assess anatomical cervix features in pregnant women: 
position and length.
To establish the acceptability and tolerance of the use of the 
Cerclage Pessary by pregnant women.
To evaluate local and systemic safety in pregnant women 
using the Cerclage Pessary.
Study Design
Randomized, open-label, controlled clinical study of efficacy.
Study population
Inclusion Criteria
Exclusion Criteria
Voluntary patients:
1.Women with single pregnancy and a cervical length of 10 mm -
25 mm between 16 and 24 weeks of gestation, without any 
previous risk factors.
2.Women with single pregnancy and a cervical length ≥ 10 mm 
between 16 and 24 weeks of gestation, and pre-existing risk 
factors for preterm birth:
Previous preterm birth before week 35.
Previous rupture of membranes before week 35.
1. Pregnancies with:
Major fetal abnormalities, such as lethal malformations 
or malformations requiring pre-or post-natal surgery, 
and fetal death before randomization.
History of rupture of membranes or prophylactic 

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cerclage in the current pregnancy before inclusion into 
the study.
Planned number of 
participants
2. Cervical or vaginal injuries prior to insertion of the pessary 
(e.g. cervical erosion secondary to trauma, infection or carcinoma, 
vesicovaginal or rectovaginal fistulas).
3.Unconscious, severely ill, mentally disabled patients, or under 16 
years of age.
4. Patients for whom use of progesterone is contraindicated.
5. Patients with history of thrombosis.
A sample consisting of 270 pregnant women at risk of preterm 
birth, with useful information for the analysis and recruited in the 
4 participating sites. This population will be divided into 3 groups 
of treatment, with 90 participants each.
The 3 groups of the clinical trial are: One control group with 
progesterone 200 mg vaginal capsules and 2 study groups with 2 
different doses of progesterone in the pessaries.
Investigational Product
Cerclage pessaries containing 6.3 g or 7.7g of sustained-release 
micronized progesterone each.
Outcomes to be 
evaluated
Primary
Secondary
Determination of the effective dose of progesterone in the 
cerclage pessary through the occurrence of spontaneous birth 
before 32 (31 6/7) and 34 (33 6/7) weeks of gestation.
Occurrence of rupture of membranes:
Premature rupture of membranes before 32 (31 6/7) and 34 
(33 6/7) weeks of gestation.
Cervical anatomic changes
1. Cervical length and internal cervical os dilation before and after 
inserting the pessary.
2. Cervical position in relation to the uterus longitudinal axis 
before and after inserting the medicated pessary.
Acceptability:
1. Ease of insertion
2. Pain of the patient at the time of insertion
3. Assessment based on the VAS during use
4. Spontaneous expulsion of the pessary
5. Request for early removal of the pessary
6. Subjective changes of vaginal discharge
Local safety:
Major maternal complications attributable to the pessary 
(chorioamnionitis, severe vaginal or cervical trauma).
Length of the Study 
21 –48 months 

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2
RATIONALE
Nowadays, prematurity is a central issue both for obstetrics as well as for public 
health worldwide, as it is a highly incident clinical situation (affecting approximately 7% to 
10% of births), and is involved in around 50 -75% of neonatal morbidities and mortalities, 
mainly in neonates born before 32 weeks of gestation. Sequelae in premature neonates also 
impact on the increase of healthcare costs and infant mortality during the first year of life 
(1).
The rate of preterm births has not declined over the last 20 years, and in most 
developed countries it remains high despite advances in the knowledge about risk factors 
and mechanisms related to preterm births (2). Essentially, there are two reasons that explain 
the failure to reduce preterm births: first, the absence of a screening method effective for the 
identification of women at high risk for this event; and second, the lack of effective 
intervention to prevent this complication.
The most commonly adopted approach for identification of pregnancies at high risk 
for preterm birth has been the use of obstetrical history and mother’s demographics.
In published screening studies where over 60,000 women with single pregnancies 
were included, the preterm birth rate by week 34 in England was 1.8%, very similar to that 
found in our country (1.3%). Preterm births were spontaneous in two-thirds of the cases 
(1.2% of the total), whereas one-third were iatrogenic. Only in 3% of cases, the patients had 
a history of preterm birth and this group accounted for 15% of the total number of 
spontaneous deliveries by week 34 only. This demonstrates that identification of patients at 
risk of delivery before week 34 based on obstetric history leaves most of these patients 
outside of the risk group, and therefore, not covered by preventive measures.
An effective method for prenatal screening to detect the risk of preterm birth is the 
measurement of the cervical length by ultrasound between gestation weeks 20 and 25. The 
risk of preterm birth both for single-fetus as well as for twin pregnancies is inversely related 
to the cervical length. Therefore, a woman with a cervical length (CL) between 1-10 mm 
has a risk of preterm birth of 44%, whereas a woman with a CL between 26-30 mm has a 
risk of 1.3%. The group with cervix measures of 1 to 15mm corresponded to 28% of all 
spontaneous deliveries before week 34, and the group with a cervix measure of 16 to 25 
mm corresponded to 21% (3).
In addition to the myriad of scientific evidence available from the studies above, they 
allow to state that the lower a certain cervical length in the second trimester of pregnancy, 
the higher the risk of spontaneous preterm birth both in single and twin pregnancies (4). 
However, there is still no consensus on the accurate definition for "short cervix" during 
gestation related to preterm birth risk prediction. Almost every women before 14 weeks of 
gestation including those at increased risk of preterm birth will have a normal cervical 
length (CL). A CL of 25 mm at this gestational age is only seen in women with a history of 
miscarriage in the second trimester, or who have undergone cervical surgery (cone). A CL 
in the range of 25-50 mm is normal between 14 and 24 weeks in all pregnant women. In 
women at low risk of preterm birth, the mean CL between 14-30 weeks of gestation is 35-
40 mm, and the 10th percentile is 25 mm, while the 90th percentile lies in 50 mm. The 
optimal timing for measurement of the CL by transvaginal ultrasound should be accurately 
established since, if performed before 14 weeks, a separate visualization of the cervix from 
the lower uterine segment may be very difficult. In addition, after week 30, the cervix is 

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progressively shortened in preparation for a full-term delivery, so in asymptomatic women, 
a CL <25 mm after 30 weeks is physiological and indicative of a non-preterm birth (5).
Most women who have a preterm birth display a shortened neck for the first time 
approximately between 18-22 weeks of gestation, so the initial examination should be 
conducted at least within that period. Besides the already established inverse relationship 
between CL and the risk of preterm birth, the earlier the cervix is shortened during 
gestation, the higher the likelihood of a preterm birth. In women at higher risk, a CL <25 
mm has apositive predictive value of 70% for preterm birth before 35 weeks when detected 
at 14-18 weeks, and 40% when detected at 18-22 weeks (5). In the same line of evidence, 
Vaisbuch et al. (4) recently demonstrated an approximate two-fold risk of delivery before 
28 or 32 weeks if CL is ≤15 mm before 20 weeks (76.9% and 80.8%) versus 20-24 weeks 
(30.9% and 48.1%). Overall, this evidence suggests that starting the screening of patients 
with cervix measurements earlier than week 18 and using a 25-mm CL limit to determine 
the need for an intervention as discussed in this clinical study might entail a greater 
advantage.
Preventing the Preterm Birth
The traditional practice for prevention of preterm birth is the administration of 
tocolytics to patients threatened to, or into premature labor. Although tocolytics 
administration has been used for several decades, systematic reviews of randomized studies 
have reported no improvement in the neonatal outcome with the administration of such 
agents or a decrease in the frequency of preterm births (7). Prophylactic administration of 
progesterone to women with a history of preterm birth and to those with short cervix and 
single-fetus pregnancy in mid-gestation has shown to significantly reduce the rate of 
spontaneous preterm birth (about 40-45% less) before week 33-34. However, there are 55-
60% of patients remaining with shortened cervix who likewise and despite progesterone 
administration, gave birth by week 34 (8-10), which is in line with the multi-causal nature 
of this condition in humans.
Progesterone mechanism of action to prevent preterm births seems to be related in 
part with a local anti-inflammatory effect that stops or slows-down the pathway of 
biochemical events involved in cervical maturation and, on the other hand, by means of a 
mild inhibitory effect of uterine contractions (13).
The cervical cerclage surgical procedure has also been proposed as a prevention 
alternative in pregnant patients with single-fetus and short cervix. However, results in 
patients without previous history of cervical incompetence are still controversial. A recent 
publication shows that results in the prevention of preterm birthusing cerclage for the 
indication of short cervix are similar in the group in which cerclage is indicated on the basis 
of the obstetric history. Thus, there would not be a rationale for expecting the cervical 
shortening to occur in order to perform the procedure (14). On the other hand, multiple 
observational studies and a recent randomized clinical study in patients with short cervix 
before 24 weeks of gestation show that the placement of a cerclage pessary (without 
surgery) significantly reduces the riskof preterm birth as compared to control patients (15-
17). Previous evidence suggests that a mechanical factor—probably a cervical distension 
and/or pressure on the inner cervical os—seems to be also related to early cervical maturity 
and the risk of preterm birth.

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Under normal conditions, an immature cervix in a pregnant woman is displaced 
posteriorly toward the sacrum, whereby the intrauterine and fetal presentation pressure are 
exerted on the uterine segment and not on the inner cervical os
(18), thus preventing early dilatation.
Cerclage Pessary without Drug Substance
The cerclage pessary mechanism of action in the prevention of preterm birth has not 
been fully elucidated. Theoretically, the effect of the pessary is based on its mechanical 
capability to displace the cervix posteriorly, hence slightly increasing the cervix length and 
changing the angle of the cervical uterus. All these variations not only reinforce the cervical 
canal, but also reduce the likelihood for membranes to make contact with the vaginal 
environment, thus contributing to preserve its integrity (20). An additional benefit of the 
cerclage pessary may be that it contributes to maintain the immunological barrier between 
the extraovular chorio-amniotic space and the microbiology flora in the vagina–a 
mechanism similar to that postulated for surgical cerclage.
 
 
In a paired-analysis, retrospective study on women with twin 
pregnancies and a cervical length below the 10th percentile by routine ultrasound, 23 cases 
were treated with the pessary and 23 received expectant management. The spontaneous 
delivery rate before week 32 was 0% in the group with pessary and 30% in the control 
group (p <0.001). In the same study, 12 women with single pregnancies were treated with 
the pessary and other 12 were treated with expectant management. The spontaneous preterm 
birth rate before week 36 was 0% in the group with pessary and 50% in the control group (p 
<0.001) (16). There are many other observational or case-control studies about the use of 
pessaries for preventing preterm birth. These studies date back to 1959 and have resulted in 
a promising absence of severe adverse effects (23).
A recent study that included 385 patients with single-fetus pregnancies and shortened 
cervix confirms the findings above, even though the magnitude of reduction in the 
prematurity rate for the control group appears to be disproportionately high (17, 20).
 
 
 
 
Development of a Cerclage Pessary containing Sustained-Release Progesterone
 
 
 
 
 
 
 
 

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On the basis of the same principle, the development of a cerclage pessary containing 
progesterone, which is released in a sustained manner upon implantation around the cervix, 
has been initiated. 
 
 
Characteristics of the Cerclage Pessary with Sustained-Release Progesterone
 
 
 
 
 
 
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STUDY OBJECTIVES
Primary Objective:This is a Phase II clinical study to assess the efficacy of two cerclage 
pessaries containing 6.3g and 7.7g of sustained-release micronized progesterone for the 
prevention of preterm birth, established by spontaneous delivery before gestation weeks 32 
(31 6/7) and 34 (33 6/7) when the pessary is inserted between weeks 16 and 24 and 
removed in gestation week 36 6/7, in pregnant women at risk of preterm birth.
Secondary Objectives:
•
To record occurrence of premature rupture of membranes before gestation weeks 32 
and 34.
•
To assess anatomical cervix features in pregnant women: position and length.
•
To establish acceptability and tolerance in pregnant women using the Cerclage 
Pessary.
•
To evaluate local and systemic safety in pregnant women using the Cerclage Pessary.

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4
STUDY DESIGN
The study will be conducted in compliance with the protocol, the good clinical 
practice standards, and the provisions of the corresponding ethics committee.
This will be a randomized, open-label, controlled, multicenter, exploratory Phase II 
study of efficacy. Pregnant patients with a single fetus who after reading the informed 
consent voluntarily agree to participate in the study will be included.
For secondary outcomes, patients will be their own controls on the following 
endpoints to be tested: cervix anatomical features—position and length—; plasma and 
endometrial progesterone concentrations in non-pregnant menopausal women; surveys on 
pregnant women to establish the acceptability and tolerance of the intervention; and local 
and systemic safety issues.
4.1. Pregnant Volunteers: 270 + 10% pregnant women at risk of preterm birth from the 4 
participating sites will be recruited. This population will be divided into 3 treatment groups 
with 90 participants each.
They will be informed and invited to participate in the study at prenatal and/or ultrasound 
control between 16 and 24 weeks of gestation. Volunteers will be included in all cases up to 
24 (0/0) weeks of gestation. Volunteers will be selected on the basis of their clinical history 
and by transvaginal ultrasound performed between weeks 16 and 24. All volunteers with a 
single pregnancy and cervical length ≤25 mm but ≥10 mm will be invited to participate in 
the study. Prior to inclusion in the study, fetal vitality or other exclusion factors discussed in 
detail below will be confirmed. Those patients who do not agree to participate in the study 
will receive the current standard care at each participating site depending on their condition.
4.1.1. Inclusion criteria in pregnant volunteers:
Pregnant women with a single fetus with a cervical length of 10-25 mm between 
16 and 24 weeks of gestation with no pre-existing risk factors.
Women with ongoing pregnancy between 16 and 24 weeks of gestation with a 
single fetus and cervical length ≥10mm, and having pre-existing risk factors in 
the immediately previous pregnancy characterized by:
-
Preterm birth before week 35 (with a viable fetus).
-
Premature rupture of membranes before week 35 (with a viable fetus).
4.1.2. Exclusion criteria in pregnant volunteers

Pregnancies with:
-
Major fetal abnormalities in the current pregnancy such as: lethal 
malformations, or requiring pre-or post-natal surgery; and fetal death prior 
to randomization.
-
History of rupture of membranes or prophylactic cerclage in the current 
pregnancy before inclusion into the study.

Cervical and/or vaginal injuries prior to insertion of the pessary (e.g., 
cervical erosion secondary to trauma, infection or carcinoma, 
vesicovaginal or rectovaginal fistulas).

Unconscious, severely ill, mentally disabled patients, or under 16 years 
of age.

Patients for whom use of progesterone is contraindicated.

Participants with history of thrombosis.

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5
PROCEDURES
5.1. Recruitment and Screening
Patients will participate voluntarily and under informed consent. Participant selection 
will be performed by screening the general population of pregnant women with single fetus 
monitored by the Hospital Healthcare Network, to investigate by serial transvaginal 
ultrasound performed between gestation weeks 16 (0/7) and 24 (0/7) those patients who 
have a cervical length between 10 mm and 25 mm, and/or women with a single fetus and 
cervical length ≥10 mm presenting one or more of the following risk factors: a) preterm 
birth prior to 35 (34 6/7) weeks of gestation; b) premature rupture of membranes prior to 35 
(34 6/7) weeks of gestation.
Gestational age will be determined by the last menstruation date and will be 
confirmed by measurement of the craniocaudal length obtained in the first trimester 
ultrasound, or by measurement of the cephalic circumference in the second trimester 
ultrasound predominating the actual date of the last menstrual period (LMPad).
The selected volunteers will be examined and those with vaginal discharge will 
undergo clinical examination and/or bacteriological investigation and if confirmed for 
infection, this will be treated with the appropriate antibiotic. In these cases, insertion of the 
sustained-release progesterone cerclage pessary will be performed subsequent to the end of 
treatment although before 24 (0/1) weeks of gestation.
5.2. Study groups
Patients will be randomly assigned to the following 3 study groups:
-Control study group: They will be instructed to administer a micronized progesterone 
200mg capsule by vaginal route on a daily basis.
-Pessary study group A: They will have a pessary with 6.3g of sustained-release 
progesterone inserted for a period of about 4 to 5 months. This procedure will be 
performed by a professional qualified and trained for these purposes.
-Pessary study group B: They will have apessary with 7.7 g of sustained-release 
progesterone inserted for a period of about 4 to 5 months. This procedure will be 
performed by a professional qualified and trained for these purposes.
5.3. Randomization
The randomization program will be generated by an independent statistician. This 
program will be linked in sequential numbers with the treatment code randomly assigned. 
The randomization plan will be kept by a qualified person from Laboratorio Andromaco 
until the database is clean and ready for analysis. Treatment will be dispensed according to 
the randomization plan. Women with single pregnancy chosen will be randomized to 
receive one of the vaginal formulations of the study. For the next volunteer, the Site will 
have the next randomized number available. Each woman will receive only the formulation 
corresponding to their randomization number. The investigator will record on the file the 
randomization number and the code printed on every formulation container. The 
coordinator of each site will assignthe randomization code to the volunteers.

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5.4. Intervention and follow-up
The intervention and follow-up of participants will begin after the conditions eligible 
to participate in the study are verified, proceeding as follows:
5.4.1. For selected participants with pre-existing risk factors, these are: immediately 
previous pregnancy terminated prematurely with preterm birth, or premature rupture 
of membranes before 35 weeks of gestation; placement of a progesterone cerclage 
pessary, or treatment with progesterone capsules will start at week 16 (0/7) but not 
beyond 24 (0/7) weeks of gestation. These participants will have a transvaginal 
ultrasound performed to document the length (≥10 mm) and position of the cervix at 
the placement of the pessary or the start of treatment with vaginal progesterone 
capsules.
5.4.2. For pregnant patients with a single fetus, selected for the presence of a 
shortened cervix (between 10 mm and 25 mm), the pessary will be inserted or the 
vaginal administration of progesterone capsules will be started at the time of the 
investigation, but not before 16 (0/7) weeks of gestation and not after 24 (0/7) weeks 
of gestation. The cervix angulation relative to the uterus body using the intersection 
of the uterus posterior wall longitudinal axis with the cervical canal axis in addition 
to a measurement of the cervical length will be performed on 60% of the study 
participants assigned to one of the two groups with medicated pessary, prior to 
insertion of the pessary and after its insertion, by means of a transvaginal ultrasound 
technique recently described (25). The transvaginal ultrasonography post-insertion of 
the pessaries may be performed at visit one or at visit two at the latest.
5.4.3. After insertion of the pessary or beginning of the administration with vaginal 
progesterone capsules and until 28 weeks of gestation, participants in the 3 treatment 
groups will be monitored every 4 weeks at the most or more often, if the site has 
established so as a control standard. After 28 weeks, patients should be monitored 
every 2 weeks. At every control visit, procedures applicable to their prenatal control 
and a transvaginal ultrasound by standard technique will be performed (patients 
receiving vaginal capsules), if considered necessary by the physician, or transvaginal 
using the technique recently described (25) (in patients with medicated pessary) to 
measure and record cervical length. The occurrence of possible side effects, 
adherence to treatment, and visits or hospitalizations due to threat or preterm labor 
will also be recorded, as well as the existence of potential causes for ex-post
exclusion from the study. In addition, concomitant medication will be recorded at 
each visit.
5.4.4 Management of participants consulting due to a threat or premature labor will 
be conducted according to the diagnostic and therapeutic guidelines of the Ministry 
of Health (MINSAL) (Clinical Guide for Preventing Preterm Birth -MINSAL 2010) 
and the respective hospital’s Obstetrics and Gynecology Service. In these cases,the 
treating physician will be provided with information about the progesterone treatment 
the patient is receiving in the study, and the decision for her continuation in the 
clinical study will be made jointly as far as possible, since the opinion of the treating 
physician shall predominate.
5.4.5 Every case will be closed at 36 6/7 weeks of gestation, or at the time of preterm 
birth. Data on the birth, condition at birth, and evolution of infants born preterm will 
be analyzed, recording morbidity and mortality through the time of discharge from 
the hospital.
The participant’s attending health team (physicians and midwives) will be informed in 
writing about the participation of these women in the study by means of an identification 

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card that will be given to every woman participating in the study. In the pregnancy card, 
participation of these subjects in the study will be emphasized by means of a self-adhesive 
sticker detailing their participation in one of the treatment groups (pessary or capsule) and 
recorded in the medical history.
5.5. Placement and repositioning of the cerclage pessary containing sustained-release 
progesterone
Once the cervix length and positioning have been examined by transvaginal 
ultrasound, and any vaginal infection has been ruled out or treated, the progesterone pessary 
should be implanted by a professional qualified and trained for that purpose. For placement, 
the participant must be lying in supine position. 
 
 
 
 
 
 The removal of the pessary will be done by vaginal 
examination at week 36 6/7 or earlier, if there is any medical indication for induction of
premature labor or elective cesarean section. The pessary will also be removed from 
participants in preterm birth labor not responding to treatment with tocolytics.
During controls or visits to emergency departments or medical offices, participants 
who report vaginal discharge should be examined by a physician to rule out infection by 
relevant testing (vaginal discharge smears for PCR), and deliver the appropriate treatment 
without the need to remove the pessary. This condition will be considered an adverse event.
In the event that the medicated cerclage pessary is spontaneously expelled it, will be 
repositioned within maximum 72 hours; if this does not occur, the patient will be withdrawn 
from the study but considered in the final statistical analysis under the intention-to-treat 
principle.
5.6. Adherence and resuming the treatment in patients assigned to the group treated with 
vaginal progesterone capsules.
Use of capsules at least during 80% of the exposure time, and resuming the treatment 
not later than72 hours after discontinuation for any cause will be considered an acceptable 
adherence to treatment. If adherence of a patient is below 80% or the treatment is 
interrupted for more than 72 hours, she will be withdrawn from the study but considered in 
thefinal statistical analysis.
5.7. Study participant withdrawal
The progesterone cerclage pessary will be removed if the patient requests so, or if 
there is any adverse event not responding to treatment alternatives such as pathological 
vaginal discharge non-responsive to antibiotic therapy. These participants will not be 
replaced and the information collected from them will be included in the analysis since this 
is based on the intention-to-treat principle.
Follow-up of subjects withdrawn from the investigational product will be the same as 
the standard follow-up.

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5.8. Recording, quality control, and data management
Information about the characteristics of the participants, including demographics 
(race, age, parity, measures for calculation of body mass index [BMI]), and the medical and 
obstetrical records will be obtained directly from the participants and recorded in the study 
file. Information about the outcome of the pregnancy will be obtained from the hospital’s 
medical records file or treating physician. Medical records of participants experiencing 
preterm birth labor before weeks 32 and 34 will be reviewed to determine the cause and 
establish whether the delivery was because of medical indication or spontaneous. 
Spontaneous deliveries will include thosewith prior preterm labor and those with rupture of 
membranes before the onset of labor. Quality control for screening, information 
management, and monitoring of adherence to protocol across the four sites will be 
performed regularly by the clinical study monitor.
6
MATERIALS AND SUPPLIES 
Cerclage pessaries containing sustained-release progesterone will be manufactured by 
Laboratorios AndrómacoS.A. Both the pessaries as well as the 200 mg progesterone soft 
capsules to be administered by vaginal route will be supplied to participants free of charge 
by Laboratorios Andrómaco S.A.

Vaginal formulations of the study:
-
Capsules containing 200 mg of micronized progesterone for vaginal 
administration.
- 
Vaginal device consisting of a cerclage pessary containing 6.3g of sustained-
release progesterone.
-
Vaginal device consisting of a cerclage pessary containing 7.7 g of sustained-
release progesterone.
Laboratorios Andrómaco S.A. will be responsible for printing the applicable codes on 
every container of study formulation.
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OUTCOMES OF INTEREST
7.1. Primary Outcomes:
Determination of the progesterone effective dose in the cerclage pessary by non-
occurrence of spontaneous delivery before 32 and 34 weeks of gestation.
7.2. Secondary Outcomes:
7.2.1. Occurrence of rupture of membranes:
7.2.1.1. Premature rupture of membranes before 32 and 34 weeks of gestation.
7.2.2. Cervical anatomic changes
7.2.2.1. Cervical length before and after the insertion of the progesterone pessary.
7.2.2.2. Cervix positionrelative to the longitudinal axis of the uterusbefore and after 
insertion of the progesterone pessary considering that this measurement 
may be performed on the same day of the pessary insertion or at Visit 2.

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7.2.2.3. Measurement of the utero-cervical angle formed by the posterior wall of the 
uterus and the longitudinal axis of the cervix before and after insertion of 
the progesterone pessary.
7.2.3 Acceptability
7.2.3.1 Ease of insertion. Measured by means of a questionnaire.
7.2.3.2. Pain of the patient at the time of insertion and during use of the pessary. The 
VAS will be applied from 1 to 10 at Visit 1 (admission, where questions 1 
to 3 will be answered) and at the final study visit (where questions 4 and 
onwards will be answered).
7.2.3.3. Request for early removal of the pessary. Date, gestational age and reason for 
the pessary removal request will be recorded in the data record file.
7.2.3.4. Spontaneous expulsion of the pessary: Date and gestational age at the time of 
expulsion of the pessary without replacement will be recorded in the data 
record file.
7.2.3.5. Changes in vaginal discharge. The participant will be questioned about the 
presence, quantity, and physical characteristics of the discharge at every 
control visit. The clinical signs and symptoms of the patient will also be 
recorded.
7.2.4. Local safety
7.2.4.1. Pain, irritation, pruritus, infection occurring in the patient during treatment.
7.2.4.2. Major maternal complications attributable to the pessary such as 
chorioamnionitis, severe vaginal or cervical trauma.
8
ADVERSE EVENTS
An adverse experience is defined as an unfavorable and unexpected change in the 
structure, function, or chemistry of the body, transiently associated with the use of the study 
product, whether or not related to the use of the drug. Any worsening (i.e., any adverse 
change clinically significant in terms of frequency or severity) of a pre-existing condition 
that is transiently associated with use of the study product is also an adverse experience.
Adverse eventswill be documented from the time of enrollment (i.e., at the time of 
signing the informed consent form) through the last scheduled contact as per the protocol, 
i.e., the date of the last visit/contact (may be a phone call, for example, in case the 
participant withdraws from the study).
Definition of Serious Adverse Event (SAE)
A SAE is any medical incidence that, at any dose:

Results in death; or

Is life-threatening (puts the subject, from the investigator
's perspective, in an 
immediate risk of death due to the experience that took place. This includes direct 
life-threatening experiences but not those that could potentially put life at risk), or

Requires or prolongs hospitalization of the patient (hospitalization is defined as an 
admission, regardless of length of stay, even if hospitalization is a precautionary 
measure in order to continuously monitor the patient). If this hospitalization is due 
to a non-worsening pre-existing condition, it is not to be considered as a serious 
adverse experience.

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
Results inpersistent or significant inability/disability (major impairment to the 
ability to perform daily life functions); or

Is an abnormal congenital defect or birth defect

Is considered a clinically significant medical event
A scheduled hospital admission, for example, for elective surgery, is not considered a 
SAE if documented at the time of enrollment.
All patients randomized in the study are pregnant women, therefore, hospitalizations 
related to scheduled parturitions/full term deliveries will not be considered as adverse 
events nor as serious or relevant adverse events.
Definition of Adverse Event of Special Interest
Adverse events of special interest are adverse events considered important for 
assessment of the safety profile regardless of seriousness, expectancy, and severity 
classification.
Preterm birth is the birth of a fetus before 37 weeks of pregnancy. Preterm birth will be 
considered an event of special interest and should consequently be reported within 24 hours.
Expected Adverse Events
Expected Adverse Events will be evaluated by the Sponsor.
An unexpected adverse event is one where the nature or severity is not consistent with the 
information contained in the relevant source document, i.e. the Investigator Brochure.
In addition, reports that add significant information about the specificity or seriousness 
of a known, already documented adverse reactionare unexpected adverse events. For 
example, an adverse event more specific or more serious than expected would be 
considered "unexpected."
Definition of Adverse Drug Reactions
An Adverse Drug Reaction is any harmful and undesirable response to an 
Investigational Medicinal Product (IMP) or drug, regardless of the dose administered.
All adverse events reported by subjects spontaneously at any time point should also be 
documented.
All adverse events should be documented in the CRF with the following information 
according to the case:
•Description (adverse events reported within the term)
•Start date
•End date or continuation
•Whether the adverse event was serious
•Severity

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•Outcome
•Mitigation actions
•Causal relationship with the IMP
•Definition of severity
The clinical severity of an adverse event will be classified as:
Mild:
The signs and symptoms can be easily tolerated. Symptoms may be ignored and 
disappear when the subject is distracted.
Moderate
Symptoms cause discomfort but are tolerable, not ignorable, impairing concentration 
ability
Severe
Symptoms affecting daily life activities.
For adverse events where intensity changes over time, the maximum intensity observed 
throughout the adverse event will be documented.
Adverse events that occur during the enrollment period, but prior to the first 
administration of the IMP and worsen during or after administration of the IMP will be 
documented as new adverse events.
Definition of outcomes at the time of the last observation of the adverse event
The outcome at the time of the last observation will be classified as:

Recovered/Resolved

Recovering/Resolving

Not recovered/Not resolved

Recovered/Resolved with sequelae

Fatal

Unknown (unknown should only be used if, at the time of the subject’s last visit in 
a trial, the outcome of the adverse event is unknown to the investigator, for 
example, because the subject was a lost to follow-up)
Definition of the mitigation actions:
None:
No mitigation actions have been provided
Start of new 
medication:
Start of new medication or change in the dosage or route of 
administration of a drug due to an adverse event (which will be 
listed before/concomitantly with the medication sheet) that is used 
as a mitigation action.
Interruption of 
the study:
Discontinuation of the subject participation in the study was 
required due to an adverse event.
Other:
Allother mitigation actions, e.g., physical therapy, surgery.

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With the exception of “none”, multiple mitigation actions can be taken for an adverse 
event.
Classification of causality:
The causal relationship of an adverse event to the investigational product will be 
classified according to terminology as follows. The proposed criteria for each term are to be 
considered and not exhaustive and neither are required to be entirely fulfilled for choosing 
the respective term:
Terms for 
classification of 
causality 
Criteria for choosing causality classification terms
Conditional/Unclassifi
ed
Additional data for proper evaluation are under examination.
Not Evaluable/Not
Assessment of available data may not be performed because the 
information is insufficient or contradictory, and may not be 
Classifiable:
supplemented or verified.
Unrelated:
Data with sufficient evidence to accept that there is no causal 
relationship with the administration of the IMP (i.e., there is no 
time relationship with the administration of the investigational 
product or another cause has been proved).
Not possible:
Data without sufficient evidence to accept that there is no causal 
relationshipto the administration of the IMP, though neither with 
evidence or argument to suggest a causal relationship (e.g., the 
temporal relationship with the administration of the investigational 
product makes a causal relationship unlikely and other drugs, 
chemicals, or underlying disease[s] provide plausible explanations).
Possible:
Data or a foundation with limited evidence suggesting a causal 
relationship (e.g. existence of a reasonable time sequence with the 
administration of the drug, but the adverse event could also be 
explained by concurrent disease[s] or other drugs or chemicals. 
Information regarding drug abstinence may not exist or be unclear).
Probable/Possible
Data or a foundation of enough evidence to suggest a causal 
relationship (e.g. existence ofa reasonable time sequence with 
administration of the drug, the adverse event is unlikely to be 
attributed to concurrent disease[s] or other drugs or chemicals, and 
the response regarding dechallenge is clinically reasonable).
Certain
Data with evidence of a causal relationship (i.e., a clinical event, 
including alterations in laboratory tests, occurs under a plausible 
relationship with the time of administration of the drug, and 
simultaneous disease or other drugs or chemical substances may not 
explain it. Response to drug dechallenge should be well-defined 
and clinically plausible, using a successful rechallenge procedure 
where appropriate).
Follow-up of subjects with an adverse event

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Follow-up on any clinically relevant, laboratory abnormality, or vital signs result adverse 
event will be performed until a satisfactory solution or stabilization is reached, or the 
clinical evaluation indicates that an additional evaluation is not warranted.
Reporting serious adverse events
Any serious adverse event (SAE) regardless of cause, occurring to any woman admitted 
into the study, must be notified by the Principal Investigator within 24 hours to 
DrugSafetyCOE@grunenthal.com,and to the respective Institutional Review Boards. 
These reports should include all supporting documentation available (with the name of the 
subject crossed out) for each event, the summary of the hospital discharge.
The Technical Director of Laboratorios Andrómaco S.A., Rodrigo Jara 
will communicate the SAE to the local health regulatory authorities. Every SAE 
must be followed until it is completely characterized. This report must be sent earlier than 2 
days after the study staff were notified of the event.
The Principal Investigator must submit a report called a Security Report Form (SRF), 
which includes a description of the event, the therapy initiated, and the testing procedures. The 
following information must be reported with the first report of a SAE:

Study identification

Subject identification

Subject’s dateof birth (if available) or age (at the onset of the adverse event)

Gender of the subject

Indicate whether the condition was pre-existing or not, and if so, if it worsened

First administration of the IMP (date and time, if available)

Last administration ofthe IMP (date and time, if available)

Brief description of the event, and mitigation arrangements taken, actions undertaken 
(does the adverse experience cause the study drug to be discontinued or interrupted?)

Maximum intensity

SAE severity criteria

Outcome

Concomitant medication at the onset of the event and if one of the concomitant 
medications is also suspected of having caused the event

Relevant history/pre-existing medical condition

The relationship with the study drug evaluated by the Investigator (determination of 
causality: Is the study drug the cause of the adverse experience?)
Any additional information relating to the adverse event until the termination of the 
trial or the final result shall be reported in the follow-up report without delay.
9
STATISTICS
This project aims to conduct a randomized, open-label, controlled, clinical-exploratory 
phase II study evaluating the efficacy of a cerclage pessary containing one of 2 doses of 
sustained-release micronized progesterone for prevention of preterm birth, compared to the 
treatment method currently used by obstetrics-gynecology specialists, which comprises the 
administration of one daily capsule by vaginal route of 200 mg of progesterone. A total of 

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270 pregnant participants at risk of preterm birth will be enrolled, screened, and randomized 
to the 3 groups of treatment previously described. The number of patients listed (n = 270) 
refers to the number of patients who effectively are enrolled and successfully complete the 
study. Therefore, an enrollment of at least 10% over that number (27 patients or more) 
should be considered due to the eventual withdrawal or early loss to follow-up of patients 
initially recruited.
As primary results, the proportions of spontaneous preterm delivery before gestation
weeks 32 and 34 will be compared between the control group and the 2 groups with the 
pessaries containing different doses of progesterone. The risk of spontaneous preterm birth 
from the time of inclusion in the study through the gestation weeks 32 and 34 will be 
determined by a Kaplan-Meier analysis
21, where gestational age will be the time scale and 
spontaneous delivery will be the event; elective parturitions will be censored. For the 
purpose of this analysis, pregnancies will no longer be considered as high risk for the event 
if delivery occurs at the week of gestation 34 (34 0/7) or beyond.
As secondary outcomes, those qualitative variables in pregnant participants at risk of 
preterm birth will be evaluated, and the percentage distribution of acceptability responses or 
side effects recorded will be determined. For the quantitative variables (measurements of 
length and cervical angulation), the averages and standard deviations of the values found 
will be compared. Accordingly, each participant will work as her own control.
9.1. Sample Size
The calculation of the sample size is based on the power to detect differences in the 
proportion of spontaneous delivery before 32 and 34 weeks of gestation between the 
cerclage pessary formulations with respect to the control group (vaginal capsules containing 
200 mg progesterone). Collecting data from at least 90 women in each group will provide a 
power of at least 80% to detect differences at a rate of 40% or more using a two-tailed test 
with α=0.05 for a non-correctedChi square.
We estimate that up to 10% of enrolled women may not complete the study, so it is 
planned to enroll at least 99 pregnant women per group to reach at least 198 treated with the 
cerclage pessaries, and 99 treated with soft progesterone capsules as control group (i.e., 99 
per vaginal formulation).
9.2. Statistical analysis
For quantitative variables, descriptive statistics will be used (mean, standard deviation, 
minimum, median, maximum, 95% CI, and number of observations), whereas for 
categoricalvariables, frequencies and percentages analyses will be carried out. Results will 
be tabulated by treatment arm and pooled. The different vaginal formulations and 
progesterone will be formally compared. Results on efficacy and safety will be studied for 
each group separately and pooled, if relevant.
The proportion of women reporting adverse events during treatment will be cross-
compared between the different doses using the Fisher
's exact test or the Chi-square test.
All statistical analyses will be performed using the statistical software SPSS (Version 
12) or Epistat 4.0.

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10
STUDY OVERSIGHT
A Study’s Steering Committee will be established and constituted by the medical 
advisor, clinical monitor, CORFO project Director, 
The Study’s Steering Committee is responsible for overseeing the 
progress of the study, adherence to the protocol, safety of the participants and discussion of 
new information relevant to the study.
Study Coordinators/CORFO project Director, code 
 
Medical advisor
 
Principal Investigator
At each participating site, a physician specialized in Obstetrics and Gynecology will be 
fully responsible for conducting the study at his/her site. The Principal Investigator will also 
be responsible for recruiting patients and ensuring that the study is conducted in accordance 
with the protocol and the Good Clinical Practice guidelines.
Dr. Ariel Fuentes García at the Instituto de Investigación Materno Infantil (IDIMI) 
–Maternidad, Hospital Clínico San Borja Arriarán (HCSBA).
Dr. Pablo Lavín Acevedo at the UNICERH, South Department of Obstetrics & 
Gynecology 
–
School 
of 
Medicine
UCHHospital Barros Luco
Dr. Christian Figueroa Lassalle at the CIMAF-CASR
Dr. Angélica Díaz at the Department of Obstetrics & Gynecology located at the 
Hospital Luis Tisné Brousse
11
ETHICAL CONSIDERATIONS
The sponsor of the study is Laboratorios Andrómaco S.A.
According to the established in Chile, recruitment of patients for this type of studies is 
governed by Act 20120. Before any procedure or intervention takes place, the informed 
consent form must be signed.
According to scientific evidence currently available, this study is classified as a 
“minimum risk” study for the patients and their unborn children.
12
PROTOCOL AMENDMENTS
Any substantial amendment to this protocol requires approval from the Independent 
Ethics Committee prior to its implementation.
13
ACCESS TO THE DATABASE/DOCUMENTS
Participating investigators and institutions will have access to controls, audits, 
reviews, and regulatory inspections by the entities governing the study, and will provide 
required data and documents safeguarding the identity of the participating patients.

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