REDucing Hot FLASHes in Women Using Endocrine Therapy. (REDFLASH)

Reinier de Graaf Groep

Status and phase: Enrolling; Phase 3

Conditions: Breast Cancer; Hot Flash Due to Medication

Treatments: Drug: Venlafaxine; Drug: Oxybutynin

Study type: Interventional

Funder types: Other

Identifiers

NCT06106529

REDFLASH2023-004

Details and patient eligibility

About

The goal of this randomized intrapatient cross-over study is to assess the efficacy of oxybutynin versus venlafaxine in reducing hot flashes in women using endocrine therapy after breast cancer.

The objectives it aims to answer are:

• To assess the efficacy of oxybutynin versus venlafaxine in reducing hot flashes in women using endocrine therapy after breast cancer
• To assess side effects of oxybutynin versus venlafaxine.
• To assess the personal preference of women for oxybutynin versus venlafaxine in reducing hot flashes.
• To assess quality of life of women when reducing hot flashes in women using endocrine therapy after breast cancer.

Participants will fill-out a patient diary during 15 weeks total on a daily basis and receive an (online) questionnaire three times total.

Researchers will compare two groups (venlafaxine group versus oxubutynine group) to assess its efficacy concerning hot flashes.

Enrollment: 260 estimated patients

Sex: Female

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Pre-, peri- or postmenopausal women of 18 years or above;
• Indication for endocrine therapy and already started with tamoxifen, aromatase inhibitors or luteinizing hormone-releasing hormone analogues for at least 4 weeks and planning to continue for the duration of the study;
• Experiencing hot flashes with a minimum of 14 per week for at least 1 month and desire to start a pharmacologic intervention.

Exclusion criteria

• Pregnant;
• Breast feeding;
• Patients who receive chemotherapy or immunotherapy/HER2 antibodies within the prior 8 weeks, and patients scheduled for chemotherapy during the study period;
• Palliative setting;
• Use of venlafaxine or any other antidepressants, also including St. John's wort within the previous year;
• Creatinine clearance < 30 ml/min;
• Liver cirrhosis;
• Use of gabapentin and/or calcium channel antagonists within 2 weeks of study entry;
• Use of oxybutynin before study entry;
• Use of any other substances or therapies for the treatment of hot flashes, for instance acupuncture.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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260 participants in 2 patient groups

Venlafaxine

Experimental group

Description:

In this open-label randomized controlled intrapatient cross-over study patients are randomly assigned to one of the two treatment groups. After a one week baseline period, group 1 starts with venlafaxine 37.5 mg once daily for 7 days followed by 75 mg once daily for 5 weeks followed by a two-week wash-out period (no medication), hereafter the group starts with oxybutynin 5 mg twice per day for 6 weeks total.

Treatment:

Drug: Oxybutynin

Drug: Venlafaxine

Oxybutynin

Experimental group

Description:

After a one week baseline period, group 2 starts with oxybutynin 5 mg twice per day for 6 weeks total followed by a two-week wash-out period (no medication), hereafter the group starts with venlafaxine 37.5 mg once daily for 7 days followed by 75mg once daily for 5 weeks.

Treatment:

Drug: Oxybutynin

Drug: Venlafaxine