Treatment
Letrozole clinical trials
We’re tracking 99 recruiting studies that include Letrozole, 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.
Beverly Hills, CaliforniaAges 18–80 - 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 - 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+ - 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 - 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 - 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 - 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 - NCT05228951RecruitingPhase 2
Testing four breast cancer medicines for stage II–III ER+/PR+/HER2+ cancer
This trial studies a combination of anti-cancer medicines (including trastuzumab and hormone therapy) for women with stage II–III breast cancer that is ER-, PR-, and HER2-positive. It aims to improve outcomes by attacking the cancer in different ways.
Shenyang, LiaoningAges 18–75 - NCT05638594RecruitingPhase 2
Neoadjuvant drug study for hormone- and HER2-positive breast cancer
This trial compares two combination treatment plans given before breast surgery (neoadjuvant therapy) for ER-positive and HER2-positive stage II–III breast cancer. It aims to see which plan works better to shrink the tumor and improve outcomes.
Shenyang, LiaoningAges 18–75 - NCT06354439RecruitingPhase 4
Letrozole for ectopic pregnancy treatment
This trial tests whether letrozole (a hormone-blocking pill) can treat an ectopic pregnancy safely and effectively, allowing you to keep your ability to have children. It is an alternative to methotrexate, and you'll be randomly assigned to one of the two treatments.
Porto Alegre, Rio Grande do SulAges 18 years+ - NCT05487092Recruiting
Letrozole to help prevent endometrioma coming back after surgery
This study tests whether taking letrozole after laparoscopic ovarian cyst surgery can lower the chance that an endometrioma (a type of ovarian endometriosis cyst) comes back. It may help some people reduce recurrence after the cyst is removed.
Hong KongAges 18–45 - NCT07492394RecruitingPhase 2
Testing dalpiciclib with or without entinostat and letrozole for early breast cancer
This trial is testing a combination of three drugs (dalpiciclib, entinostat, and letrozole) for women with early-stage, hormone-receptor-positive, HER2-negative breast cancer. It aims to see if adding these medications before surgery can help shrink the tumor.
Shijiazhuang, HebeiAges 18–75 - 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+ - NCT05601700RecruitingPhase 3
Letrozole for low-grade ovarian cancer that uses hormones
This study tests whether letrozole, a hormone-blocking medicine, can help people with newly diagnosed low-grade serous ovarian cancer that has hormone receptor proteins (ER and/or PgR) after surgery. It compares outcomes to see if blocking estrogen can slow the cancer’s return or progression.
Arezzo, ARAges 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 - NCT05816655RecruitingPhase 2
Test two hormone treatment combinations for metastatic breast cancer
This Phase 2 study compares two combinations of hormone-blocking drugs plus an anti-cancer targeted pill to see which works better for hormone-receptor positive, HER2-negative metastatic breast cancer. It may help by finding a more effective treatment plan when the cancer has spread.
SeoulAges 19–80 - 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 - NCT07160855RecruitingPhase 4
Adding letrozole to standard miscarriage treatment
This trial tests whether adding letrozole (a hormone pill) to misoprostol (a medicine to complete a miscarriage) works better than misoprostol alone for ending a missed miscarriage in early pregnancy. It aims to make the process safer and possibly faster.
Multan, Punjab ProvinceAges 18–45 - 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+ - 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 - NCT07014410RecruitingPhase 2
Pyrotinib, dalpiciclib, and letrozole for advanced breast cancer
This trial tests a combination of three targeted drugs for a type of advanced breast cancer that is both ER-positive and HER2-positive. The goal is to see if adding these two new drugs to standard hormone therapy can help shrink or control the cancer.
Hangzhou, ZhejiangAges 18–75
What Letrozole is being studied for
Conditions with recruiting Letrozole studies.
Common questions
- Are there clinical trials studying Letrozole?
- Yes. Clin2 currently lists 99 recruiting studies that include Letrozole, drawn from the U.S. registry and rewritten for real people so you can see what each is testing and who it's for.
- How do I know if I qualify for a Letrozole trial?
- Each study lists its own eligibility criteria — rules about condition, age, and prior treatments. On every Clin2 trial page we explain these in plain language and offer a short, optional pre-screen for a fit read. The study team makes the final decision.
- Is Letrozole an approved treatment?
- A drug being studied in a trial may be investigational (still being tested) or already approved and being studied for a new use. Each study page explains what phase it's in. Clin2 does not provide medical advice — talk with your doctor about whether Letrozole or a specific trial is right for you.
Related treatments
Clin2 helps you find and understand clinical trials and does not provide medical advice. Study data comes from ClinicalTrials.gov. A drug appearing here is being studied in a trial and may be investigational. Talk with your doctor about whether a specific treatment or trial is right for you.