Treatment
Letrozole clinical trials
We’re tracking 103 recruiting studies that include Letrozole, each written for real people, not researchers, below.
Recruiting studies
- 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+ - NCT04852887RecruitingPhase 3
Testing shorter breast radiation after low-risk hormone breast cancer
This Phase 3 trial studies whether “less intense” radiation can work as well as standard radiation for certain early-stage hormone receptor–positive, HER2-negative breast cancers that have a low Oncotype DX score. It may help reduce treatment burden while keeping cancer control strong.
Birmingham, AlabamaAges 50–70 - NCT05181033RecruitingPhase 2
Lenvatinib plus letrozole versus fulvestrant for metastatic breast cancer
This Phase 2 study compares a combination medicine (lenvatinib plus letrozole) against fulvestrant to treat metastatic estrogen-receptor positive, HER2-negative breast cancer after the cancer has grown despite hormone therapy plus a CDK4/6 inhibitor. It may help by finding a more effective treatment option after your first lines have stopped working.
SingaporeAges 18–99 - 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 - NCT05247268RecruitingPhase 2
Hormone therapy to shrink early uterine cancer in young women
This trial tests whether combining two hormone medicines can treat early endometrial (uterine) cancer while helping preserve the uterus and future fertility. You may be eligible if your cancer is early and limited, with no spread seen on scans, and you can safely take these medicines.
ShanghaiAges 18–45 - NCT05316935RecruitingPhase 2/Phase 3
Hormone therapy for certain early uterine lining cancers without obesity
This trial tests whether adding GnRH medicine and letrozole to standard progestin treatment can better control early, low-risk endometrial cancer or atypical hyperplasia in people who are not obese. It may help some patients avoid progression while keeping the uterus, especially for those wanting future fertility.
Shanghai, Shanghai MunicipalityAges 18–45 - 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 - 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+ - 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 - NCT05744687RecruitingPhase 2/Phase 3
Letrozole plus SPH4336 versus letrozole alone for breast cancer
This study tests whether adding SPH4336 to letrozole works better than letrozole plus a placebo for treating hormone-receptor–positive, HER2-negative breast cancer in people starting first-line treatment. It may help slow cancer growth more effectively if the added drug is beneficial.
Fuzhou, FujianAges 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 - NCT06139107RecruitingPhase 1
Radiation and abemaciclib plus letrozole before breast cancer surgery
This trial combines a short course of radiation before surgery with two oral medications (abemaciclib and letrozole) to treat early-stage, hormone-sensitive breast cancer. The goal is to see if this approach can shrink the tumor and improve outcomes.
Belleville, New JerseyAges 60 years+ - 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+ - NCT06379113RecruitingPhase 2/Phase 3
Hormone therapy for obesity-linked endometrial cancer that didn't respond to progestin
This trial tests a combination of two hormone-blocking drugs (GnRHa plus letrozole) for women with early-stage, obesity-related endometrial cancer who haven't responded well to standard hormone therapy alone. The goal is to preserve the uterus and fertility while controlling the cancer.
Shanghai, Shanghai MunicipalityAges 18–45 - NCT06757634RecruitingPhase 3
A study of gedatolisib for first-line advanced breast cancer
This trial tests a new targeted therapy called gedatolisib for people with HR-positive, HER2-negative advanced breast cancer who have not yet received treatment for metastatic disease. It aims to see if adding this drug to standard hormone therapy can help control the cancer longer.
Duarte, CaliforniaAges 18 years+ - 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 - 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 - NCT01042379RecruitingPhase 2
Adaptive drug trial for newly diagnosed breast cancer
This study tests personalized, changing treatment plans (given before surgery) to find better options for your specific breast tumor. You may be asked for extra breast-tissue testing to help match you with the most suitable study drug(s).
Birmingham, AlabamaAges 18 years+ - 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 - NCT03424005RecruitingPhase 1/Phase 2
Testing new drug combinations for advanced breast cancer
This study tests how well and how safely different combinations of cancer drugs work for people with metastatic or inoperable locally advanced breast cancer. It may help by finding a better treatment option and collecting information to guide future care.
Duarte, CaliforniaAges 18 years+ - NCT07391774RecruitingPhase 3
Hormone therapy with or without chemo for early breast cancer
This trial tests whether skipping chemotherapy and using only hormone therapy with a drug called ribociclib works as well as chemotherapy followed by hormone therapy with ribociclib for certain early breast cancers that have a low risk of coming back.
Jonesboro, ArkansasAges 18 years+ - NCT06930859Recruiting
Study of Ribociclib for HR+ HER2-negative breast cancer in Russia
This study looks at how well ribociclib works when given with hormone therapy after surgery for certain types of breast cancer. It aims to understand real-world benefits and safety for patients in Russia.
Sochi, Russian FederationAges 18–99 - NCT05512364RecruitingPhase 3
Elacestrant for ER-positive, HER2-negative breast cancer with ctDNA relapse
This trial tests whether elacestrant can help stop or delay breast cancer coming back in people whose blood test shows “ctDNA relapse” after early breast cancer treatment. It’s meant for hormone receptor–positive, HER2-negative breast cancer patients who are already taking hormone (endocrine) therapy and have no visible spread on scans.
AnderlechtAges 18 years+ - NCT06998407RecruitingPhase 1/Phase 2
Study of AVZO-023 for advanced solid tumors
This trial tests a new drug, AVZO-023, alone or with other treatments, for people with advanced solid tumors that have not responded to standard therapy. The goal is to see if it can shrink tumors or slow their growth.
Los Angeles, CaliforniaAges 18 years+
Common questions
- Are there clinical trials studying Letrozole?
- Yes. Clin2 currently lists 103 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.