REDucing Hot FLASHes in Women Using Endocrine Therapy.

Phase 3

Recruiting

• Conditions: Breast Cancer; Hot Flash Due to Medication
• Interventions: Drug: Oxybutynin; Drug: Venlafaxine

• Registration Number: NCT06106529
• Lead Sponsor: Reinier de Graaf Groep

Brief Summary

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.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2023-10-24
• Study First Submitted QC: 2023-10-24
• Study First Posted: 2023-10-30
• Study Start: 2024-10-03
• Status Verified: 2025-01
• Last Update Submitted: 2025-01-31
• Last Update Posted: 2025-02-04
• Primary Completion: 2029-01-01
• Study Completion: 2029-01-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Female
• Target Recruitment: 260

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.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Venlafaxine	Venlafaxine	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.
Oxybutynin	Venlafaxine	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.
Venlafaxine	Oxybutynin	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.
Oxybutynin	Oxybutynin	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.

Primary Outcome Measures

Name	Time	Method
Number and severity of hot flashes	15 weeks total	Number and severity of hot flashes during 6-weeks of therapy measured by the Hot Flash Diary.

Secondary Outcome Measures

Name	Time	Method
Sexual function	15 weeks total	Sexual function measured at baseline and after 6 weeks of treatment with the Sexual Activity Questionnaire (SAQ)
Sleep quality	15 weeks total	Sleep quality at baseline and after 6 weeks of treatment measured by the Groningen Sleep Quality Scale (GSQ)
Adverse effects of treatments	15 weeks total	Adverse effects of treatments weekly measured by the National Cancer Institute Common Toxicity Criteria scale, version 5
Anxiety and depression	15 weeks total	Anxiety and depression measured at baseline and after 6 weeks of treatment with the Hospital Anxiety and Depression Scale (HADS)
Adherence	15 weeks total	Ask patients the following question after 6 weeks of treatment: 'Would you like to continue the endocrine therapy for the recommended duration of therapy taking the current medication (oxybutynin or venlafaxine) given the number and severity of hot flashes you experience during the last week?'
Quality of life and health status	15 weeks total	Quality of life and health status at baseline and after 6 weeks of treatment measured by the EORTC-QLQ-C30
Cognitive function	15 weeks total	Cognitive function measured at baseline and after 6 weeks of treatment with the 6-item cognitive impairment test (6-CIT)
Preference	15 weeks total	Ask patients the following question after 6 weeks of the final treatment: 'Do you have a preference taking the medication from study period 1 or study period 2?'

Trial Locations

Locations (1)

Reinier de Graaf Gasthuis; 🇳🇱 Delft, Zuid-Holland, Netherlands