NCT06831955

LifEStyle Intervention to Enhance Efficacy of Neoadjuvant Therapy in Patients With Triple Negative Breast Cancer

The LESLIE Trial: LifEStyle Intervention to Enhance Efficacy of Neoadjuvant Systemic Therapy in Patients With Triple Negative Breast Cancer

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 356 (estimated)
• Sponsor: Universitaire Ziekenhuizen KU Leuven · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

LESLIE is a multicentric randomized controlled trial in patients with triple negative breast cancer receiving neoadjuvant chemo/immunotherapy (NAT). This trial investigates the hypothesis that adding a cyclic fasting-mimicking diet combined with exercise during the NAT improves the NAT's therapeutic efficacy, treatment tolerability and compliance, as well as improve quality of life.

Detailed description

Leslie is a 2-arms randomized (2:1) Phase IIb clinical trial including 356 patients that will investigate whether combining a cyclic FMD-based intervention with exercise concomitant with neoadjuvant systemic therapy may have a beneficial effect on treatment response, survival, treatment tolerability and compliance, as well as quality of life of patients with TNBC. The neoadjuvant treatment will last for 21 weeks in both arms. Visits to the day clinic will be scheduled for administration of Standard of Care (SOC) in combination with 2-weekly visits to physiotherapists and online support of onco-dietician for patients from arm B. The control group (arm A): SOC neoadjuvant therapy is based on the systemic treatment regimen described in the Keynote 522 trial, apart from some minor changes. It consists of four cycles of an intravenous infusion of pembrolizumab (200 mg) once every 3 weeks plus paclitaxel (80 mg per square meter of body-surface area once weekly) plus carboplatin (at a dose based on an area under the concentration-time curve of 1.5 mg per milliliter per minute) once weekly in the first 12 weeks, followed by four cycles of epirubicin (90 mg per square meter) plus cyclophosphamide (600 mg per square meter) once every 2 weeks plus pembrolizumab 400mg every 6 weeks or pembrolizumab 200mg every 3 weeks in the subsequent 8 weeks. All treatments after surgery will be administered according to the institutional guidelines. The interventional group (arm B): Next to the SOC, the lifestyle intervention (cyclic FMD and exercise) will be part of the treatment. The FMD is a plant-based, low-carbohydrate, low-caloric diet of 4 days , with the fourth day being the day of chemo/immunotherapy. A total of 6 FMD cycles will be administered over the treatment period of 20 weeks. The exercise regimen consists of a non-linear aerobic exercise program of 3-4 sessions per week. During days of FMD no exercise will be prescribed.

Conditions

• Triple Negative Breast Cancer (TNBC), Early Setting

Interventions

Type	Name	Description
OTHER	Exercise Therapy	The exercise regimen consists of a non-linear aerobic exercise program of 3-4 sessions per week. During days of FMD no exercise will be prescribed.
DIETARY_SUPPLEMENT	Fasting-Mimicking Diet	The FMD is a plant-based, low-carbohydrate, low-caloric diet of 4 days , with the fourth day being the day of chemo/immunotherapy. A total of 6 FMD cycles will be administered over the treatment period of 20 weeks.
DRUG	SOC	Four cycles of an intravenous infusion of pembrolizumab (200 mg) once every 3 weeks plus paclitaxel (80 mg per square meter of body-surface area once weekly) plus carboplatin (at a dose based on an area under the concentration-time curve of 1.5 mg per milliliter per minute) once weekly in the first 12 weeks, followed by four cycles of epirubicin (90 mg per square meter) plus cyclophosphamide (600 mg per square meter) once every 2 weeks plus pembrolizumab 400mg every 6 weeks or pembrolizumab 200mg every 3 weeks in the subsequent 8 weeks.

Timeline

• Start date: 2026-02-01
• Primary completion: 2028-09-01
• Completion: 2031-09-01
• First posted: 2025-02-18
• Last updated: 2026-03-20

Locations

10 sites across 1 country: Belgium