Treatment
Letrozole clinical trials
We’re tracking 99 recruiting studies that include Letrozole, each written for real people, not researchers, below.
Recruiting studies
- 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 - 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.
Jonesboro, ArkansasAges 18 years+ - 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 - 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 - 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+ - 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 - 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+ - 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+ - 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+ - 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+ - 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 - 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 - 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 - 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+ - 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+ - 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 - 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+ - NCT06366347RecruitingPhase 2
Maintenance letrozole and abemaciclib for advanced endometrial cancer
This trial tests whether taking two oral medications (letrozole and abemaciclib) after standard chemotherapy can help keep advanced or recurrent endometrial cancer from coming back. It is for people whose cancer is estrogen receptor-positive and has certain favorable genetic features.
Aurora, ColoradoAges 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+ - NCT03458221RecruitingPhase 2/Phase 3
Biology-guided test on recurrent ovarian cancer activity
This trial studies whether a targeted treatment, chosen based on tumor biology, can help people with recurrent ovarian cancer. You may be asked to give a tumor biopsy so researchers can analyze specific “signal” activity in your cancer.
Nijmegen, GelderlandAges 18 years+ - NCT05891093RecruitingPhase 3
Fluzoparib plus hormone therapy after surgery for breast cancer
This Phase 3 trial tests whether fluzoparib added to standard hormone (endocrine) therapy after early breast cancer surgery can improve outcomes and safety. It may help patients whose tumors are ER-positive, HER2-negative, and a specific SNF3 subtype.
Beijing, Beijing MunicipalityAges 18–70 - NCT07604571RecruitingPhase 1
Testing IEV407 for Advanced Hormone-Sensitive Breast Cancer
This study tests a new drug called IEV407, either alone or combined with existing hormone therapies, in people with advanced breast cancer that is hormone-receptor positive and HER2 negative. The trial aims to find the right dose and see if this combination helps people whose cancer has stopped responding to previous treatments.
New Haven, ConnecticutAges 18 years+ - NCT04985266RecruitingPhase 2
Watch blood DNA for early breast cancer return, then add palbociclib
This study checks for early signs that ER-positive, HER2-negative breast cancer may be coming back by testing your blood for cancer DNA. If signs are found, it tests whether adding palbociclib plus fulvestrant works better than standard hormone therapy alone to prevent recurrence.
AngersAges 18 years+ - NCT07581834RecruitingPhase 2
Dalpiciclib plus hormone therapy for early hormone-positive breast cancer
This study tests whether adding a new drug called dalpiciclib to standard hormone therapy improves outcomes for women with early-stage breast cancer that is hormone-receptor positive. The goal is to see if this combination is more effective and safe than hormone therapy alone.
Fuzhou, FujianAges 18 years+
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.