A Phase 1 interventional study of Letrozole LEBE 75 mg and Letrozole LEBE 150 mg in Healthy, sponsored by Rovi Pharmaceuticals Laboratories. Completed at 1 site in Czechia. Open to female participants aged 18 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-07-24.
Sponsored by Rovi Pharmaceuticals Laboratories · Phase 1, Interventional, and Treatment
Among 176 studies in Breast Neoplasms with a site in Czechia — 21 open to participants now, 44 under way, 31 of them phase 3. Breast Neoplasms · Czechia.
Among the 176 studies in Breast Neoplasms with a site in Czechia, this one is the 148th largest by enrollment of the 160 interventional ones that give a count, is one of 7 that started in 2023, is one of 3 in phase 1, and was the 153rd registered.
14,829 studies on the registry are indexed under Breast Neoplasms; 3,318 are open to participants now.
Browse Breast Neoplasms studies →21 of the 176 studies in Breast Neoplasms with a site in Czechia are open now. Recruiting first, the newest first:
Hoffmann-La Roche · Sites in Czechia, United States, Argentina and 23 more countries
Ages 18+
Novartis Pharmaceuticals · Sites in Czechia, United States, Canada and 8 more countries
Ages 18+
Masaryk Memorial Cancer Institute · Sites in Czechia
Ages 20–55 · Women only · Healthy volunteers
Olema Pharmaceuticals, Inc. · Sites in Czechia, United States, Australia and 20 more countries
Ages 18+
BioNTech SE · Sites in Czechia, United States, Argentina and 16 more countries
Ages 18+
A study can be open while its sites in Czechia have not opened yet or have stopped. Only those recruiting at a site in Czechia →
Of the 2,398 Breast Neoplasms studies recruiting now, 1,569 (65%) set no upper age limit and 592 (25%) stop at 75 or younger; 103 take children under 18; 215 take healthy volunteers.
This study: 18 Years to 75 Years · female · healthy volunteers too.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
176 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 14 · Phase 2 49 · Phase 3 103
First in 1996; this study’s year is marked. 7 started in 2023.
By drug class, each counting the studies that test any of its medicines:
This study's enrollment of 84 is above the median of 72 across 10,900 interventional studies indexed under Breast Neoplasms.
Median enrollment 504 across the 160 interventional studies, 200 across the 15 observational. Of the 130 that completed or were terminated, 98 (75%) have results posted.
This tab as a report to print or save as PDF → With an account.
155 of 176 have an industry lead sponsor. The 10 most frequent:
Rovi Pharmaceuticals Laboratories is the lead sponsor of 19 studies on the registry; 2 are open to participants now.
Rovi Pharmaceuticals Laboratories has 3 studies filed under Breast Neoplasms — fewer than ten, so there is no comparison to draw.
12 of the studies in Breast Neoplasms with a site in Czechia that are under way reach primary completion within a year, 8 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT05038735Phase 3Novartis PharmaceuticalsStudy to Assess the Efficacy and Safety of Alpelisib Plus Fulvestrant in Participants With HR-positive (HR+), HER2-negative, Advanced Breast Cancer After Treatment With a CDK4/6 Inhibitor and an Aromatase Inhibitor. | 2027-01-28 |
| NCT04873362Phase 3Hoffmann-La RocheA Study Evaluating the Efficacy and Safety of Adjuvant Atezolizumab or Placebo and Trastuzumab Emtansine for Participants With HER2-Positive Breast Cancer at High Risk of Recurrence Following Preoperative Therapy | 2027-03-31 |
| NCT04421963Phase 3AstraZenecaRoll Over StudY for Patients Who Have Completed a Previous Oncology Study With Olaparib | 2027-04-06 |
| NCT05774951Phase 3AstraZenecaA Study of Camizestrant in ER+/HER2- Early Breast Cancer After at Least 2 Years of Standard Adjuvant Endocrine Therapy | 2027-04-20 |
| NCT06312176Phase 3Merck Sharp & Dohme LLCA Study of Sacituzumab Tirumotecan (MK-2870) as a Single Agent and in Combination With Pembrolizumab (MK-3475) Versus Treatment of Physician's Choice in Participants With HR+/HER2- Unresectable Locally Advanced or Metastatic Breast Cancer (MK-2870-010) | 2027-07-11 |
Add all 12 to your calendar (.ics) → With an account.
Among the 176 studies in Breast Neoplasms with a site in Czechia, from their registry updates:
This tab as a report to print or save as PDF → With an account.
This is a Phase I, open label, sequential, single ascending dose (SAD) study to evaluate the pharmacokinetic (PK), safety, and tolerability of Letrozole LEBE in healthy post-menopausal women.
The study consists of 1 Screening Period and 2 treatment periods. Evaluation of eligibility and allocation of subject number to the volunteers will be performed after Screening. It is planned that subjects will be enrolled in three groups of approximately 30 subjects in each group (Groups 1 to 3), in order to ensure 15 completed subjects per group in Treatment Period 1 and Treatment Period 2. In Treatment Period 1, each subject will sequentially receive 1 dose daily of oral Femara (2.5 mg) over a period of 14 days followed by a single intramuscular (IM) dose of Letrozole LEBE (after a washout period) in Treatment Period 2. Ascending doses of Letrozole LEBE will be given to Groups 1, 2 and 3. Safety and tolerability will be assessed in all groups by the incidence and severity of Adverse Events (AEs) and Serious AEs (SAEs), concomitant medication use, vital sign assessments, clinical laboratory evaluations, 12 lead ECGs, physical examination, and body weight/BMI. The end of the clinical trial will be the last visit of the last subject at Day 197 of Treatment Period 2 or any additionally required 4-weeks safety follow up visits, when plasma levels of letrozole are detectable, whichever occurs later. Those remaining subjects with detectable plasma levels of letrozole could be followed every 4 weeks.
The sample size was estimated based on a minimum number necessary to obtain a preliminary assessment regarding the drug's PK and safety profile over the planned dose range. No formal sample size calculation was made for this study.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: Letrozole LEBE 75 mg
Drug: Letrozole LEBE 150 mg
Drug: Letrozole LEBE 225 mg
14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 75 mg
14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 150 mg
14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 225mg
λz
Terminal phase elimination rate constant
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Cmax
Maximum observed plasma concentration after Letrozole LEBE administration
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Clast
Last observed plasma concentration after Letrozole LEBE administration
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
tmax
Time to maximum observed concentration
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
tlag
Lag time before observation of quantifiable concentrations in plasma.
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
t1/2
Terminal elimination half life.
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
AUC∞
Area under the concentration time curve from time zero extrapolated to infinity.
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
AUClast
Area under the concentration time curve from time zero up to the last quantifiable concentration.
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
E1
Estrone
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
SE1
Sulfate estrone
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
E2
Estradiol
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
λz
Terminal phase elimination rate constant.
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Cav
Average plasma concentration over a dosing interval.
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Cmin, ss
Minimum observed plasma concentration at steady-state.
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Cmax,ss
Maximum observed plasma concentration at steady-state
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
tmax
Time to maximum observed concentration.
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
t1/2
Terminal elimination half-life.
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
AUCτ
Area under the concentration-time curve over a dosing interval.
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Ran from Jul 2023 to primary completion in Mar 2026, 31 months.
Of 389 industry-sponsored phase 1 interventional studies under Breast Neoplasms, half reached primary completion within 39 months of starting (the median), counting those still running; a quarter within 22 and three quarters within 56. This study's 31 months is below that.
Counting every sponsor, half of 761 studies reached it within 44 months; a quarter within 25 and three quarters within 65.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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Rovi Pharmaceuticals Laboratories