Letrozole for Estrogen/Progesterone Receptor Positive Low-grade Serous Epithelial Ovarian Cancer (LEPRE Trial)

NCT05601700RecruitingPHASE3INTERVENTIONAL

Summary

Key Facts

Lead Sponsor

Ente Ospedaliero Ospedali Galliera

Enrollment

132

Start Date

2022-09-22

Completion Date

2029-09-22

Study Type

INTERVENTIONAL

Official Title

Letrozole for Estrogen/Progesterone Receptor Positive Low-grade Serous Epithelial Ovarian Cancer: a Randomized Phase III Trial (LEPRE Trial)

Interventions

Letrozole tabletscarboplatin AUC 5 and paclitaxel 175 mg/m2

Conditions

CarcinomaOvarian EpithelialLow Grade Serous Adenocarcinoma of Ovary

Eligibility

Age Range

18 Years+

Sex

FEMALE

Inclusion Criteria:

I - 1. Age ≥ 18 years. I - 2. Newly diagnosed, low-grade serous carcinoma of the ovary including cancer of fallopian tube and peritoneum (invasive micropapillary serous carcinoma or invasive grade 1 serous carcinoma). This is to be confirmed via nuclear p53 immunohistochemistry testing by a central pathology review performed at the Coordinating Centre.

I - 3. Immunohistochemically determined positivity (≥ 10%) for ER and/or PgR expression. This is to be confirmed by centralized review.

I - 4. Patients must have undergone an upfront surgery with maximal cytoreductive effort, with either optimal or suboptimal residual disease status.

I - 5. Stage III-IV according to 2018 FIGO classification. For proper staging:

* Patients must have undergone contrast-enhanced CT-scan of the chest, abdomen and pelvis within 28 days prior to randomization. If CT-scan is not recommended (e.g. for allergy to contrast agent) MRI or 18F-FDG PET/CT-scan are allowed.
* The imaging evaluation must be accompanied by an anamnestic and physical examination within 14 days prior to randomization.

I - 6. Postmenopausal, defined as any of the following criteria:

* Patients who underwent bilateral salpingo-oophorectomy;
* Monolateral salpingo-oophorectomy, amenorrhea for 12 or more consecutive months and age ≥60 years;
* Monolateral salpingo-oophorectomy, amenorrhea for 12 or more consecutive months, age \<60 years and FSH and serum estradiol levels within the laboratory's reference ranges for post-menopausal women.

I - 7. Randomization must take place within 60 days of primary cytoreductive surgery.

I - 8. Eastern Cooperative Oncology Group - performance status (ECOG-PS) 0-1.

I - 9. To be able to take oral medications.

I - 10. Adequate bone marrow, hepatic and renal functions as defined below:

* Absolute neutrophil count (ANC) ≥ 1500/mm3
* Platelets ≥ 100,000/mm3
* Hemoglobin ≥ 10.0 g/dL
* Total bilirubin ≤ 1.5 x Upper Limit of Normal (ULN)
* ALT and AST ≤ 3.0 x ULN
* Alkaline phosphatase ≤ 2.5 x ULN
* Albumin ≥ 2.8 g/dL
* Serum creatinine ≤ 1.5 x ULN.

I - 11. Written informed consent obtained prior to any study-specific procedure.

Exclusion Criteria:

E - 1. Other malignancy within the last 5 years, except for non-melanoma skin cancer adequately treated.

E - 2. Neoadjuvant chemotherapy or radiotherapy for the treatment of this disease.

E - 3. Previous hormonal therapy for the treatment of this disease.

E - 4. Known hypersensitivity to letrozole or known hypersensitivity/intolerance to carboplatin/paclitaxel therapy.

E - 5. Active or uncontrolled systemic infection.

E - 6. Known central nervous system metastases.

E - 7. Severe cardiac disease, such as myocardial infarction or unstable angina within 6 months prior to randomization.

E - 8. New York Heart Association (NYHA) Class III or greater congestive heart failure.

E - 9. Neuropathy grade 2 or higher.

E - 10. History of fractures of the spine or femur not properly treated.

E - 11. Known osteoporosis (dual-energy x-ray absorptiometry (DEXA) of the femoral neck T score of -2.5 or lower) not adequately treated with bisphosphonates or RANKL inhibitors.

E - 12. Concomitant use of inducers of CYP3A4 (e.g. phenytoin, rifampicin, carbamazepine, phenobarbital, and St. John's Wort) which may reduce exposure to letrozole. Concomitant use of medicinal products with a narrow therapeutic index that are substrates for CYP2C19 (e.g. phenytoin, clopidrogel) that may have their systemic serum concentrations altered by letrozole.

E - 13. Concurrent severe medical problems or any condition that would significantly limit full compliance with the study.

Outcome Measures

Primary Outcomes

Progression-free survival (PFS)

the time from the date of randomization to the date of local or regional relapse, distant metastasis, or death from any cause, whichever comes first. Patients not recurred, not progressed or not died while on study or patients lost to f-up will be censored at their last disease assessment date.

Time frame: 54 months up to 84 months

Secondary Outcomes

Objective Response Rate (ORR)

the percentage of patients with an objective response, i.e. patients who will experience a complete response (CR), or a partial response (PR) as determined by RECIST 1.1. Each patient will be assigned the best response ever recorded during the trial.

Time frame: 54 months up to 84 months

Predictive effect of ER and PgR (% expression) on response to letrozole in terms of PFS and ORR

the time from the date of randomization to the date of local or regional relapse, distant metastasis, or death from any cause, whichever comes first according to ER and PgR % expression.

Time frame: 54 months up to 84 months

Clinical Benefit (CB)

the percentage of patients who will experience a CR or PR or stable disease (SD). Each patient will be assigned the best response ever recorded during the trial.

Time frame: 54 months up to 84 months

Overall survival (OS)

the time from the date of randomization to the date of death from any cause. Patients not reported as having died at the end of the study will be censored at the date they were last known to be alive.

Time frame: 54 months up to 84 months

Safety (Adverse Events)

Number of Participants With Treatment-Related Adverse Events as Assessed by CTCAE

Time frame: 54 months up to 84 months

Locations

Ospedale San Donato, Arezzo, Italy

Ospedale degli Infermi, Ponderano, Italy

Ospedale San Martino, Belluno, Italy

Fondazione Poliambulanza, Brescia, Italy

ASST degli Spedali Civili di Brescia, Brescia, Italy

Ospedale Sant'Anna, Como, Italy

IRST, Meldola, Italy

AOU Ferrara, Ferrara, Italy

Medical Oncology Division, Ente Ospedaliero Ospedali Galliera, Genova, Italy

Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy

IEO, Milan, Italy

IRCCS Istituto Oncologico Veneto, Padua, Italy

IFO Regina Elena, Roma, Italy

Policlinico Umberto I, Roma, Italy

Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma, Italy

IRCCS Istituto Oncologico Veneto, Castelfranco Veneto, Italy

Ospedale Ca' Foncello, Treviso, Italy

Ospedale Del Ponte, Varese, Italy

AUSL Romagna, Rimini, Italy

Linked Papers

2025-12-14

Letrozole for hormone receptor–positive low-grade ovarian cancer: Preliminary toxicity results of a phase III trial

Background: Epidemiological and retrospective studies suggest that letrozole may improve outcomes in low-grade serous carcinoma of the ovary (LGSCO) by targeting estrogen-driven tumor progression. Methods: We designed a multicenter, randomized, open-label, phase III trial to compare letrozole versus standard chemotherapy (carboplatin plus paclitaxel) in prolonging progression-free survival (PFS). Secondary endpoints include overall survival (OS), objective response rate (ORR), quality of life (MENQoL), and musculoskeletal pain (BPI-SF). Translational objectives explore mutational and expression profiles (NGS, RAD51/BRCA1 foci) and circulating tumor DNA (ctDNA) as markers of treatment response. Eligible patients are postmenopausal women with stage III–IV ER/PgR-positive LGSCO after primary cytoreductive surgery. Patients are randomized 1:1 to letrozole 2.5 mg daily until progression or unacceptable toxicity, or to carboplatin-paclitaxel for 6–8 cycles. Disease progression is assessed by RECIST, CA-125, and imaging every 3–6 months. Results: As of March 2025, 46 patients have been randomized (23 per arm). Preliminary analysis shows a favorable safety profile for letrozole compared with chemotherapy. Conclusions: Early findings suggest letrozole is well tolerated and may represent a viable therapeutic option for hormone receptor-positive LGSCO. Ongoing molecular and clinical analyses will clarify its role in this rare subtype. Trial registration: ClinicalTrials.gov Identifier: NCT05601700; https://clinicaltrials.gov/study/NCT05601700

Linked Investigators