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A Comparison of Letrozole and Clomifene Citrate

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ClinicalTrials.gov Identifier: NCT02647424
Recruitment Status : Unknown
Verified October 2016 by The University of Hong Kong.
Recruitment status was:  Recruiting
First Posted : January 6, 2016
Last Update Posted : October 27, 2016
Sponsor:
Information provided by (Responsible Party):
The University of Hong Kong

Brief Summary:

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies, affecting 5% to 10% of women of reproductive age. Women with PCOS suffer from anovulatory infertility. Following lifestyle modification with weight reduction in obese PCOS women, clomifene citrate (CC) is considered the first line treatment for ovulation induction (OI) in these women. 75-80% of women will ovulate after CC administration. However, there is a discrepancy between the ovulation rate and pregnancy rate, which was reported to be 22% per each ovulating cycles after CC. Other alternatives, including gonadotropin injections and laparoscopic ovarian drilling, carried different disadvantages, such as costly treatment and risks of ovarian hyperstimulation syndrome and multiple pregnancy rate in gonadotrophin therapy and surgical risks and risk of ovarian failure in surgical treatment.

The use of aromatase inhibitor, letrozole (LTZ), in reproductive medicine started in 2001. After this publication, there have been many groups of investigators studying the use of LTZ either in OI or ovarian stimulation in IVF cycles. A large multicentre randomized trial reported a significantly higher ovulation rate and live-birth rate comparing LTZ with CC. In majority of the publications, the multiple pregnancy rate was lower in LTZ group than in CC group. This can be attributed to the higher chance of monofollicular development after LTZ compared with CC. However, there is no information comparing the hormonal profile and follicular development after letrozole and CC.

Mild ovarian stimulation using LTZ or CC in conjunction with intrauterine insemination is commonly offered to ovulatory women with unexplained infertility, minimal endometriosis or mild factor to improve the pregnancy rate. There is again no information comparing the hormonal profile and follicular development after letrozole and CC in ovulatory women.

The aim of this study is to compare the hormonal profile after the use of LTZ and CC in anovulatory PCOS women and ovulatory women with unexplained subfertility. The hypothesis is that the FSH risk after LTZ is shorter than that of CC.


Condition or disease Intervention/treatment Phase
Polycystic Ovarian Syndrome Subfertility Drug: Letrozole Drug: Clomiphene Not Applicable

Detailed Description:

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies, affecting 5% to 10% of women of reproductive age. Women with PCOS suffer from anovulatory infertility. Following lifestyle modification with weight reduction in obese PCOS women, clomifene citrate (CC) is considered the first line treatment for ovulation induction (OI) in these women. 75-80% of women will ovulate after CC administration. However, there is a discrepancy between the ovulation rate and pregnancy rate, which was reported to be 22% per each ovulating cycles after CC. Other alternatives, including gonadotropin injections and laparoscopic ovarian drilling, carried different disadvantages, such as costly treatment and risks of ovarian hyperstimulation syndrome and multiple pregnancy rate in gonadotrophin therapy and surgical risks and risk of ovarian failure in surgical treatment.

The use of aromatase inhibitor, letrozole (LTZ), in reproductive medicine started in 2001. After this publication, there have been many groups of investigators studying the use of LTZ either in OI or ovarian stimulation in IVF cycles. A large multicentre randomized trial reported a significantly higher ovulation rate and live-birth rate comparing LTZ with CC. In majority of the publications, the multiple pregnancy rate was lower in LTZ group than in CC group. This can be attributed to the higher chance of monofollicular development after LTZ compared with CC. However, there is no information comparing the hormonal profile and follicular development after letrozole and CC.

Mild ovarian stimulation using LTZ or CC in conjunction with intrauterine insemination is commonly offered to ovulatory women with unexplained infertility, minimal endometriosis or mild factor to improve the pregnancy rate. There is again no information comparing the hormonal profile and follicular development after letrozole and CC in ovulatory women.

The aim of this study is to compare the hormonal profile after the use of LTZ and CC in anovulatory PCOS women and ovulatory women with unexplained subfertility. The hypothesis is that the FSH risk after LTZ is shorter than that of CC.


Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 40 participants
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: A Comparison of Hormonal Profile and the Follicular Development Between Letrozole and Clomifene Citrate in Anovulatory Women With Polycystic Ovary Syndrome and Ovulatory Women
Study Start Date : December 2015
Estimated Primary Completion Date : December 2017
Estimated Study Completion Date : December 2017

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
PCOS group
PCOS women with anovulation
Drug: Letrozole
Letrozole 2.5 mg daily from Day 2 to 6
Other Name: Letrozole group

Drug: Clomiphene
After one month of washout period, clomiphene 50 mg daily from day 2 to day 6 given
Other Name: Clomiphene group

Ovulatory group
Ovulatory group planned for intra-uterine insemination
Drug: Letrozole
Letrozole 2.5 mg daily from Day 2 to 6
Other Name: Letrozole group

Drug: Clomiphene
After one month of washout period, clomiphene 50 mg daily from day 2 to day 6 given
Other Name: Clomiphene group




Primary Outcome Measures :
  1. FSH concentrations [ Time Frame: Alternative day during ovulation induction cycle (for about 3 month) ]

Secondary Outcome Measures :
  1. LHconcentration [ Time Frame: Alternative day during ovulation induction cycles (for about 3 month) ]
  2. Endometrial Thickness [ Time Frame: Monitoring during ovulation induction cycle (for about 3 month) ]
  3. Oestradiol concentration [ Time Frame: Alternative day during ovulation induction cycles (for about 3 month) ]
  4. Progesterone concentration [ Time Frame: Alternative day during ovulation induction cycles (for about 3 month) ]
  5. Number of growing follicles [ Time Frame: Monitoring during OI cycles (for about 3 month) ]


Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 39 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   No
Criteria

Inclusion criteria:

  • Age of women 18-39 years
  • Irregular menstrual cycles with anovulation (cycle >35 days) together with polycystic ovaries on pelvic scanning or laboratory/clinical hyperandrogenism (in PCOS group)
  • Regular cycle of 25-35 days cycle for the ovulatory women group
  • Body mass index </= 30 kg/m2

Exclusion criteria:

  • Couples undergoing ART treatment cycles
  • History of ovarian surgery
  • Drug allergy to CC or LTZ
  • History of diabetes mellitus or other severe medical diseases
  • Refusal to join the study

Information from the National Library of Medicine

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): NCT02647424


Contacts
Contact: Vivian Lee, MBBS, MRCOG 22553400 v200lee@hku.hk

Locations
Hong Kong
Queen Mary Hospital Recruiting
Hong Kong, Hong Kong, 852
Contact: Vivian CY Lee, MBBS    852-22553400    v200lee@hku.hk   
Principal Investigator: Vivian Lee         
Sub-Investigator: Ernest HY Ng, MD         
Sponsors and Collaborators
The University of Hong Kong
Investigators
Principal Investigator: Vivian Lee, MBBS, MRCOG Queen Mary Hospital / University of Hong Kong.

Responsible Party: The University of Hong Kong
ClinicalTrials.gov Identifier: NCT02647424     History of Changes
Other Study ID Numbers: HKU-VL-LCC
First Posted: January 6, 2016    Key Record Dates
Last Update Posted: October 27, 2016
Last Verified: October 2016

Additional relevant MeSH terms:
Syndrome
Polycystic Ovary Syndrome
Infertility
Disease
Pathologic Processes
Ovarian Cysts
Cysts
Neoplasms
Ovarian Diseases
Adnexal Diseases
Genital Diseases, Female
Gonadal Disorders
Endocrine System Diseases
Genital Diseases, Male
Citric Acid
Letrozole
Clomiphene
Enclomiphene
Zuclomiphene
Anticoagulants
Calcium Chelating Agents
Chelating Agents
Sequestering Agents
Molecular Mechanisms of Pharmacological Action
Antineoplastic Agents
Aromatase Inhibitors
Steroid Synthesis Inhibitors
Enzyme Inhibitors
Estrogen Antagonists
Hormone Antagonists