CompletedNCT06315205LEILA-1Updated Jul 24, 2026

Evaluation of the Pharmacokinetics, Safety, and Tolerability of IM Letrozole LEBE in Healthy Post-menopausal Women

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

Phase: Phase 1
Study type: Interventional
Enrollment: 84
Allocation: Non-randomized
Ages: 18 Years to 75 Years
Sex: Female

Study 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 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 studied

Healthy

Browse trials for

Breast Neoplasms 12,520

Keywords

Pharmacokinetics
Safety
Letrozol LEBE
Intramuscular
Breast cancer

Who can participate

Ages eligible: 18 Years to 75 Years
Sexes eligible: Female
Accepts healthy volunteers: Yes

Inclusion criteria

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.

Exclusion criteria

Exclusion Criteria:

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.
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.

Study design

Phase: Phase 1
Primary purpose: Treatment
Allocation: Non-randomized
Intervention model: Sequential assignment
Masking: None (open label)
Enrollment: 84 participants (actual)

Study arms

Experimental
Cohort 1: Letrozol LEBE 75 mg
Drug: Letrozole LEBE 75 mg
Experimental
Cohort 2: Letrozol LEBE 150 mg
Drug: Letrozole LEBE 150 mg
Experimental
Cohort 3: Letrozol LEBE 225 mg
Drug: Letrozole LEBE 225 mg

Interventions

DrugLetrozole LEBE 75 mg
14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 75 mg
DrugLetrozole LEBE 150 mg
14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 150 mg
DrugLetrozole LEBE 225 mg
14 oral doses of Femara 2.5 mg/daily + 28-days (at least) washout period + single IM injection of Letrozole LEBE 225mg

What researchers measure

Primary outcomes

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

Secondary outcomes

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)

Study locations

1 site

Investigational Site number CZ-01
Prague, Czechia

Registry details

Key details

Study ID: NCT06315205
Lead sponsor: Rovi Pharmaceuticals Laboratories
Responsible party: Sponsor
First posted: Mar 18, 2024
Start date: Jul 26, 2023
Primary completion: Mar 11, 2026
Completion: Mar 11, 2026
Last update: Jul 24, 2026

Oversight

Data monitoring committee: Yes
FDA-regulated drug: No
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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