HealthyPhase 1LEILA-1NCT06315205
Evaluation of the Pharmacokinetics, Safety, and Tolerability of IM Letrozole LEBE in Healthy Post-menopausal Women
A Phase 1 study testing Letrozole LEBE 75 mg, Letrozole LEBE 150 mg and Letrozole LEBE 225 mg in people with Healthy, run by Rovi Pharmaceuticals Laboratories at 1 site in Czechia.
Trial summary
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. Read more about this study
- Who is it for?
- Ages 18 to 75 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Healthy
- What is being tested?
- Letrozole LEBE 75 mg, Letrozole LEBE 150 mg and Letrozole LEBE 225 mg
- Type of treatment
- Pill or oral medicine, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 84 participants
- Where
- 1 siteCzechia
- Study dates
- 26 Jul 2023to 11 Mar 2026
- Phase
- Phase 1
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 75 years
- Women only
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Healthy post-menopausal women.
- Capable of providing informed consent.
- Weight of ≥50 kg and a BMI ≥19 and ≤39 kg/m2.
- Subjects should be able to communicate with clinic staff.
Who cannot join
- Subjects who have a history of allergy or hypersensitivity to letrozole or any of the inactive ingredients.
- Subjects who have a history of galactose intolerance, severe hereditary lactase deficiency glucose-galactose malabsorption.
- Subjects who have used estrogen or progesterone hormone replacement therapy, thyroid replacement therapy, oral contraceptives, androgens, luteinizing hormone (LH) releasing hormone analogs, prolactin inhibitors, or antiandrogens within prior to Screening.
- Subjects who have used: any medications including St. John's wort or any medications or products known to be potent or moderate inhibitors of CYP P450 3A4.
- Subjects who have been diagnosed with osteoporosis.
- Subjects who have an abnormality at Screening or prior to first dose that in the opinion of the investigator increases the risk of participating in the study.
Show all 13Show fewer
- Subjects who have any clinically significant abnormal physical examination or laboratory safety findings at screening.
- Subjects who have relevant diseases or clinically significant abnormal relevant findings at Screening, as determined by medical history, physical examination, laboratory, ECG, DEXA, and breast and pelvic examination.
- Subjects who have history of any significant chronic disease.
- History of cancer within the past 5 years with the exception of non-melanoma skin cancer.
- Subjects who have a history of drug-dependence, and recent history of alcoholism or abuse of alcohol.
- Subjects who have received a drug in research or have participated in other clinical trials within 90 days, prior to dosing.
- Any other unspecified reason that, in the opinion of the investigator (or designee) or sponsor, makes the subject unsuitable for enrolment.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: A Phase I, Open Label, Dose Escalation Study to Evaluate the Pharmacokinetics, Safety, and Tolerability of Single Intramuscular Injections of Letrozole LEBE at Different Strengths in Voluntary Healthy Post-Menopausal Women.
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.
Read the detailed description
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.
- Conditions
- Healthy
- Being tested
- Letrozole LEBE 75 mg, Letrozole LEBE 150 mg, Letrozole LEBE 225 mg
- Keywords
- Pharmacokinetics, Safety, Letrozol LEBE, Intramuscular, Breast cancer
- Medical subject headings
- Breast Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Letrozole LEBE 75 mgDrug
14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 75 mg
Letrozole LEBE 150 mgDrug
14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 150 mg
Letrozole LEBE 225 mgDrug
14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 225mg
| Study group | Role | What they receive |
|---|---|---|
| Cohort 1: Letrozol LEBE 75 mg | Experimental | Not described Receives: Drug: Letrozole LEBE 75 mg |
| Cohort 2: Letrozol LEBE 150 mg | Experimental | Not described Receives: Drug: Letrozole LEBE 150 mg |
| Cohort 3: Letrozol LEBE 225 mg | Experimental | Not described Receives: Drug: Letrozole LEBE 225 mg |
What is being measured
The primary outcome is the main question the study is designed to answer.
λz
Terminal phase elimination rate constant
Measured: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Cmax
Maximum observed plasma concentration after Letrozole LEBE administration
Measured: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Clast
Last observed plasma concentration after Letrozole LEBE administration
Measured: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
tmax
Time to maximum observed concentration
Measured: 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.
Measured: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
t1/2
Terminal elimination half life.
Measured: 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.
Measured: 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.
Measured: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Secondary outcomes (10)
E1
Estrone
Measured: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
SE1
Sulfate estrone
Measured: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
E2
Estradiol
Measured: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
λz
Terminal phase elimination rate constant.
Measured: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Cav
Average plasma concentration over a dosing interval.
Measured: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Cmin, ss
Minimum observed plasma concentration at steady-state.
Measured: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Cmax,ss
Maximum observed plasma concentration at steady-state
Measured: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
tmax
Time to maximum observed concentration.
Measured: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
t1/2
Terminal elimination half-life.
Measured: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
AUCτ
Area under the concentration-time curve over a dosing interval.
Measured: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Mar 2024
- Study start26 Jul 2023
- Primary completion11 Mar 2026
- Study completion11 Mar 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HealthyStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Enrolment
- 84 participants (actual)
Sponsor and investigators
- Lead sponsor
- Rovi Pharmaceuticals Laboratories
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06315205
- Sponsor's protocol ID
- ROV-LEBE-2023-01
- Other IDs
- 2023-503948-13, 2023
- Acronym
- LEILA-1
- Status last verified
- Jul 2026
- First submitted
- 11 Mar 2024
- Last updated
- 24 Jul 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 24 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase I, Open Label, Dose Escalation Study to Evaluate the Pharmacokinetics, Safety, and Tolerability of Single Intramuscular Injections of Letrozole LEBE at Different Strengths in Voluntary Healthy Post-Menopausal Women.
- ClinicalTrials.gov ID
- NCT06315205
- Acronym / sponsor ID
- LEILA-1 / ROV-LEBE-2023-01
- Conditions
- Healthy
- Keywords
- Pharmacokinetics, Safety, Letrozol LEBE, Intramuscular, Breast cancer
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 84 participants (actual)
- Lead sponsor
- Rovi Pharmaceuticals LaboratoriesIndustry (pharma, biotech, devices)
- Study start
- 26 Jul 2023 (actual)
- Primary completion
- 11 Mar 2026 (actual)
- Study completion
- 11 Mar 2026 (actual)
- First posted
- 18 Mar 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
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.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Cohort 1: Letrozol LEBE 75 mg | Experimental | Drug: Letrozole LEBE 75 mg |
| Cohort 2: Letrozol LEBE 150 mg | Experimental | Drug: Letrozole LEBE 150 mg |
| Cohort 3: Letrozol LEBE 225 mg | Experimental | Drug: Letrozole LEBE 225 mg |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Healthy post-menopausal women.
- Capable of providing informed consent.
- Weight of ≥50 kg and a BMI ≥19 and ≤39 kg/m2.
- Subjects should be able to communicate with clinic staff.
Key exclusion criteria (13 listed)
- Subjects who have a history of allergy or hypersensitivity to letrozole or any of the inactive ingredients.
- Subjects who have a history of galactose intolerance, severe hereditary lactase deficiency glucose-galactose malabsorption.
- Subjects who have used estrogen or progesterone hormone replacement therapy, thyroid replacement therapy, oral contraceptives, androgens, luteinizing hormone (LH) releasing hormone analogs, prolactin inhibitors, or antiandrogens within prior to Screening.
- Subjects who have used: any medications including St. John's wort or any medications or products known to be potent or moderate inhibitors of CYP P450 3A4.
- Subjects who have been diagnosed with osteoporosis.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Letrozole LEBE 75 mg14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 75 mg | Drug | Cohort 1: Letrozol LEBE 75 mg |
| Letrozole LEBE 150 mg14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 150 mg | Drug | Cohort 2: Letrozol LEBE 150 mg |
| Letrozole LEBE 225 mg14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 225mg | Drug | Cohort 3: Letrozol LEBE 225 mg |
Primary outcome
λz
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Terminal phase elimination rate constant
Cmax
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Maximum observed plasma concentration after Letrozole LEBE administration
Clast
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Last observed plasma concentration after Letrozole LEBE administration
tmax
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Time to maximum observed concentration
tlag
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Lag time before observation of quantifiable concentrations in plasma.
t1/2
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Terminal elimination half life.
AUC∞
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Area under the concentration time curve from time zero extrapolated to infinity.
AUClast
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
Area under the concentration time curve from time zero up to the last quantifiable concentration.
10 secondary outcomes
E1
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
SE1
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
E2
Time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197
λz
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Cav
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Cmin, ss
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Cmax,ss
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
tmax
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
t1/2
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
AUCτ
Time frame: Following multiple oral administration of Femara (Treatment Period 1, Day 14)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Jul 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing Letrozole LEBE 75 mg, Letrozole LEBE 150 mg and Letrozole LEBE 225 mg in people with Healthy, run by Rovi Pharmaceuticals Laboratories at 1 site in Czechia.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 13 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 24 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Czechia. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
λz (time frame: Following single IM administration of Letrozole LEBE (Treatment Period 2, Day 1) until Day 197). The study lists 8 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Jul 2026.