Letrozole Or Clomifene for Ovulation Induction

Letrozole or Clomifene, with or without metformin, for ovulation induction in women with polycystic ovary syndrome: a 2x2 factorial design randomised trial (The LOCI trial) - LOCI: Letrozole Or Clomifene for Ovulation Induction

Status

Not yet recruiting

Phases

Phase 3

Study type

Interventional

Source

EU CTR

Registry ID

EUCTR2018-004641-16-GB

Enrollment

2100

Registered

2019-12-19

Start date

2020-02-14

Completion date

Unknown

Last updated

2020-05-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Ovulation induction for women suffering from polycystic ovary syndrome MedDRA version: 20.0 Level: LLT Classification code 10002658 Term: Anovulation System Organ Class: 100000004860 MedDRA version: 20.0 Level: LLT Classification code 10021935 Term: Infertility, female, associated with anovulation System Organ Class: 100000004872 MedDRA version: 21.1 Level: LLT Classification code 10036050 Term: Polycystic ovary System Organ Class: 100000004872 MedDRA version: 20.0 Level: PT Classification c

Interventions

Trade Name: Loxoprel 2.5 mg Film-Coated Tablets Product Name: Loxoprel 2.5 mg Film-Coated Tablets Pharmaceutical Form: Film-coated tablet INN or Proposed INN: Letrozole CAS Number: 112809-51-5 Concent

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: ? Women diagnosed with PCOS (according to Rotterdam criteria)13 and evidence of anovulation (anovulation is defined as irregular cycles lasting =65 years) no F.1.3.1 Number of subjects for this age range 0

Exclusion criteria

Exclusion criteria: ? Age =18 or =43 years at randomisation; ? Body Mass Index =35; ? Three or more previous ovulation induction treatments with either letrozole or clomifene; ? Intention to continue current use of metformin treatment or inositol supplements for ovulation induction or for other indications ? Metformin or inositol supplement use in the previous 3 months ? Women opting for alternative methods of ovulation induction or treatment (GnRH agonists and antagonists, gonadotropins), triggering ovulation with hCG, or performing intrauterine or intracervical insemination; ? Contraindications to letrozole, clomifene, metformin use and/or pregnancy (see section 7.3 for full details on contraindications). ? Woman has previously participated in the LOCI trial.

Design outcomes

Primary

Measure	Time frame
Secondary Objective: Primary Objective • To compare the paired drug effectiveness in women with anovulatory PCOS and infertility on live birth rate (= 34 weeks of gestation). Secondary Objectives • To compare the paired drug effectiveness in women with anovulatory PCOS and infertility on live birth rate (= 34 weeks of gestation). Letrozole vs clomifene To compare the effectiveness of letrozole vs clomifene in women with anovulatory PCOS and infertility on live birth rate (= 34 weeks of gestation). Metformin vs Placebo To compare the effectiveness of metformin vs placebo in women with anovulatory PCOS and infertility undergoing ovulation induction on live birth rate (= 34 weeks of gestation). Letrozole plus metformin vs clomifene plus metformin To compare the effectiveness of letrozole plus metformin vs clomifene plus metformin in women with anovulatory PCOS and infertility on live birth rate (= 34 weeks of gestation). • Collect key secondary data on: (i) Pregnancy loss (defined as pregnancy loss befo;Primary end point(s): Live births beyond 34 completed weeks of gestation, as a proportion of all women randomised.;Timepoint(s) of evaluation of this end point: End of pregnancy;Main Objective: To test the hypothesis that in women with PCOS and infertility, letrozole plus metformin versus clomifene plus metformin increases the live birth rate (= 34 weeks of gestation) by at least 10%.	—

Measure

Time frame

Secondary Objective: Primary Objective • To compare the paired drug effectiveness in women with anovulatory PCOS and infertility on live birth rate (= 34 weeks of gestation). Secondary Objectives • To compare the paired drug effectiveness in women with anovulatory PCOS and infertility on live birth rate (= 34 weeks of gestation). Letrozole vs clomifene To compare the effectiveness of letrozole vs clomifene in women with anovulatory PCOS and infertility on live birth rate (= 34 weeks of gestation). Metformin vs Placebo To compare the effectiveness of metformin vs placebo in women with anovulatory PCOS and infertility undergoing ovulation induction on live birth rate (= 34 weeks of gestation). Letrozole plus metformin vs clomifene plus metformin To compare the effectiveness of letrozole plus metformin vs clomifene plus metformin in women with anovulatory PCOS and infertility on live birth rate (= 34 weeks of gestation). • Collect key secondary data on: (i) Pregnancy loss (defined as pregnancy loss befo;Primary end point(s): Live births beyond 34 completed weeks of gestation, as a proportion of all women randomised.;Timepoint(s) of evaluation of this end point: End of pregnancy;Main Objective: To test the hypothesis that in women with PCOS and infertility, letrozole plus metformin versus clomifene plus metformin increases the live birth rate (= 34 weeks of gestation) by at least 10%.

—

Secondary

Measure	Time frame
Secondary end point(s): Miscarriage rate (defined as delivery before 24 weeks of gestation). Ongoing pregnancy at 12 weeks (range 11 to 14 weeks) of gestation. Multiple pregnancies. Ovulation rate. Time to pregnancy. ;Timepoint(s) of evaluation of this end point: 0-24 weeks.	—

Countries

United Kingdom

Contacts

Public ContactAdam Devall

University of Birmingham

a.j.devall@bham.ac.uk07971823452

Outcome results

None listed

Source: EU CTR (via WHO ICTRP) · Data processed: Feb 4, 2026