Clinical trials
Letrozole clinical trials
Below are recruiting letrozole clinical trials, each written for real people, not researchers. We’re tracking 101 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT07401381RecruitingPhase 1
Injectable vs. oral letrozole in early breast cancer
This study compares a new injectable form of the drug letrozole with the standard oral pill. It aims to find out if the injection works as well as the pill for women who have already taken letrozole for their early breast cancer and have finished their initial treatment.
MurciaAges 18–80 - NCT07492641RecruitingPhase 3
A new drug plus letrozole for advanced HR+ breast cancer
This trial tests a new medicine (BGB-43395) combined with letrozole against the usual CDK4/6 inhibitor plus letrozole. It is for people with advanced or metastatic HR-positive, HER2-negative breast cancer who have not yet had treatment for advanced disease.
Birmingham, AlabamaAges 18 years+ - NCT06372119Recruiting
Letrozole vs artificial cycle for embryo transfer preparation
This trial compares two ways to prepare the uterus for a frozen embryo transfer: using the hormone letrozole or a standard artificial cycle. The goal is to see which approach works better for people with irregular periods.
Ho Chi Minh City, Ho Chi Minh CityAges 18–42 - NCT07255911Recruiting
Comparing two medicines for ovulation in PCOS
This study tests if adding cabergoline to letrozole works better than letrozole alone to help women with PCOS ovulate. It may help participants who have not had success with standard treatments.
Dhaka, ShahbagAges 18–35 - NCT06790693RecruitingPhase 3
Inavolisib plus hormone therapy for advanced breast cancer
This trial tests a new targeted therapy, inavolisib, combined with standard hormone therapy and a CDK4/6 inhibitor for people with a specific genetic mutation (PIK3CA) in their hormone receptor-positive, HER2-negative advanced breast cancer that has not been treated before. It compares this combination to a placebo plus the same standard treatments.
Goodyear, ArizonaAges 18 years+ - NCT06555068RecruitingPhase 1/Phase 2
Study of HRS-6209 combinations for advanced breast cancer
This trial tests a new drug, HRS-6209, combined with different hormone treatments (fulvestrant, letrozole, HRS-8080, or HRS-1358) for people with advanced breast cancer that has spread or cannot be surgically removed and has worsened after previous treatments.
Shanghai, Shanghai MunicipalityAges 18–75 - NCT05851014RecruitingPhase 3
GB491 plus letrozole for HR+ HER2- advanced breast cancer
This Phase 3 study tests whether GB491 used together with letrozole works better for hormone receptor–positive and HER2-negative advanced breast cancer. You may be eligible if you have not had certain prior cancer treatments and your health tests are within safe limits.
Bengbu, AnhuiAges 18–75 - NCT06006091Recruiting
Letrozole for preparing the womb before embryo transfer
This study tests if a medicine called letrozole can help prepare the lining of the womb for a frozen embryo transfer. It may be an option for women under 40 who have had limited previous IVF cycles.
ShanghaiAges Up to 40 years - NCT07159880Recruiting
Letrozole for ovulation induction in PCOS
This trial tests a longer course of letrozole to help women with PCOS ovulate and get pregnant. The goal is to see if extended therapy works better than the standard treatment.
São Paulo, São PauloAges 18–40 - NCT07085767RecruitingPhase 3
Palazestrant and ribociclib for first-line advanced breast cancer
This trial tests a new drug (palazestrant) combined with ribociclib for people with a common type of advanced breast cancer that is estrogen receptor-positive and HER2-negative. You may qualify if you haven't had treatment for advanced disease and your cancer has either just been found or came back long after completing hormone therapy.
Hot Springs, ArkansasAges 18 years+ - NCT06244745RecruitingPhase 3
Letrozole after ovarian stimulation in egg donors
This study tests whether giving the drug letrozole after ovarian stimulation can help egg donors. The goal is to see if it reduces the risk of ovarian hyperstimulation syndrome, a side effect that can happen after donating eggs.
MadridAges 18–34 - NCT05464810RecruitingEarly Phase 1
Letrozole with or without a cholesterol drug for early breast cancer
This early-phase study tests whether adding simvastatin to letrozole can improve outcomes in people with stage I–III breast cancer that grows with hormone signals (hormone receptor positive) and does not have HER2. It looks mainly at whether the approach is safe and useful for this specific breast cancer type.
Atlanta, GeorgiaAges 18 years+ - NCT05190094RecruitingPhase 2
Test blood-based laser scan to guide first-line breast cancer treatment
This Phase 2 study uses a specialized laser test on a blood sample to predict how well palbociclib plus letrozole or anastrozole will work. It’s for certain postmenopausal women with HER2-negative, hormone-receptor positive, advanced (stage IIIb/IV) breast cancer.
BlidaAges 18 years+ - NCT04169451Recruiting
Letrozole with IUI versus natural cycle IUI
This study compares two ways of timing intrauterine insemination (IUI)—using letrozole medicine to help schedule ovulation versus using a natural (untreated) cycle. It may help couples who are trying to conceive with mild or “unexplained” infertility see which approach works better for pregnancy chances.
Beijing, Beijing MunicipalityAges 20 years+ - NCT05341817RecruitingPhase 4
Letrozole or mifepristone before medication abortion
This study tests whether taking letrozole or mifepristone before medication helps the medical abortion work better for pregnancies up to 10 weeks. You may be asked to try another method (repeat medicine or a procedure) if the first treatment does not fully work.
SingaporeAges 21 years+ - NCT06394804RecruitingPhase 2
Avutometinib, Defactinib, and Letrozole for Low-Grade Ovarian Cancer
This trial tests a combination of two oral targeted drugs (avutometinib and defactinib) plus letrozole (a hormone therapy) in people with low-grade serous ovarian cancer who have not yet had any systemic treatment.
Atlanta, GeorgiaAges 18 years+ - NCT07389733RecruitingPhase 1/Phase 2
Study of HRS-6208 with other drugs for advanced breast cancer
This trial tests a new combination of drugs (HRS-6208 with HRS-8080, fulvestrant, or letrozole) for people with advanced or metastatic breast cancer that cannot be removed by surgery. It aims to see if these combinations can help shrink or slow the cancer.
Dalian, LiaoningAges 18–75 - NCT05649956RecruitingPhase 2
Letrozole after surgery for early uterine leiomyosarcoma
This Phase 2 trial studies whether letrozole can help prevent uterine leiomyosarcoma from coming back after surgery. It focuses on people whose tumor shows estrogen receptor positivity.
Aurora, ColoradoAges 18 years+ - NCT05872204RecruitingPhase 2
Abemaciclib plus letrozole for rare ER-positive ovarian cancer
This trial tests whether abemaciclib with letrozole can slow or shrink certain rare ovarian cancers that have estrogen receptors. It may help people whose cancer has come back and can be measured on scans, with extra required tissue and blood tests.
Liège, LiègeAges 18 years+ - NCT07285382RecruitingPhase 2
Dalpiciclib plus letrozole for advanced HR+ HER2- breast cancer
This trial tests a new combination of two drugs (dalpiciclib and letrozole) as a first treatment for advanced breast cancer that is hormone receptor positive and HER2 negative. It aims to find the best dose to slow or stop cancer growth.
Dalian, LiaoningAges 18–75 - NCT06143631RecruitingPhase 4
Letrozole study for uterine fibroids
This trial tests if the drug letrozole can improve symptoms like heavy bleeding and pelvic pain caused by uterine fibroids. You must be premenopausal with moderate to severe symptoms and not have very large fibroids or certain other conditions.
Los Angeles, CaliforniaAges 21–53 - NCT03011684RecruitingPhase 3
Preserve eggs using tamoxifen and letrozole during new breast cancer treatment
This study tests whether taking tamoxifen and letrozole (with fertility injections) can help people with newly diagnosed, estrogen-sensitive breast cancer preserve eggs before cancer treatment starts. It may help protect future fertility by collecting eggs early, before chemotherapy or other treatments begin.
San Francisco, CaliforniaAges 18–50 - NCT03122197RecruitingEarly Phase 1
Letrozole for recurrent high-grade brain tumors
This early-phase study tests letrozole, a hormone-blocking medicine, in adults with recurrent high-grade gliomas. The goal is to see if it can help control the tumor and is safe enough to study further.
Cincinnati, OhioAges 18 years+ - NCT03675893RecruitingPhase 2
Test abemaciclib plus letrozole with or without extra drugs
This Phase 2 study tests whether adding medicines to standard hormone therapy (letrozole) can control endometrial cancer that has come back, spread, or stopped responding to usual treatments. It also explores whether extra drugs (metformin or gedatolisib) improve results for certain patient groups.
Boston, MassachusettsAges 18 years+
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Common questions
- Are there clinical trials for letrozole?
- Yes. Clin2 currently lists 101 recruiting letrozole studies from the U.S. registry, each rewritten for real people, not researchers, so you can see what it’s testing and who it’s for.
- How do I know if I qualify for a letrozole trial?
- Each study lists its eligibility criteria — rules about age, diagnosis, and prior treatments. On every Clin2 trial page we explain these in words written for real people and offer a short, optional pre-screen for a fit read. The study team makes the final decision.
- Does it cost anything to join a letrozole trial?
- Using Clin2 is always free. Many trials cover the cost of the study treatment and related visits; some reimburse travel. The study team explains exactly what’s covered before you decide.
Related conditions
Clin2 helps you find and understand clinical trials and does not provide medical advice. Study data comes from ClinicalTrials.gov. Talk with your doctor about whether a specific trial is right for you.