Solifenacin Compared to Clonidine for Reducing Hot Flashes Among Breast Cancer Patients

There has been considerable interest in developing new treatment strategies for managing hot
flashes among women with breast cancer, in view of the limitations associated with currently
available treatments. This randomized study evaluates the safety and efficacy of 3 weeks of
solifenacin compared to 3 weeks of clonidine, for women receiving adjuvant hormonal therapy
(aromatase inhibitors or tamoxifen) for breast cancer.

Inclusion Criteria:

- Women with a history of invasive breast cancer or DCIS

- Currently taking aromatase inhibitors or tamoxifen

- Not receiving hormone replacement therapy for minimum of one month

- Age 18 years or older

- Self-reported hot flashes greater than fourteen times per week

- Self-reported hot flashes for at least one month

Exclusion Criteria:

- Current use of clonidine or solifenacin. (If patients have been off of these for one
month, then they are eligible)

- History of severe renal or moderate or severe hepatic impairment, as indicated by
physical exam and medical record

- Concurrent or planned chemotherapy or radiotherapy (within next 3 months)

- Currently receiving monoamine oxidase inhibitors, L-dopa, piribedil, barbiturates,
moxifloxacin, pimozide, or antihypertensive treatment

- Currently using CYP3A4 inducers (i.e., aminoglutethimide, carbamazepine,
dexamethasone, efavirenz, ethosuximide, griseofulvin, modafinil, nafcillin,
nevirapine, oxcarbazepine, phenobarbital, phenylbutazone, phenytoin, primidone,
rifabutin, rifampin, rifapentine, St. John's wort, sulfadimidine, sulfinpyrazone,
troglitazone) or potent CYP3A4 inhibitors (i.e., clarithromycin, chloramphenicol,
erythromycin, imatinib mesylate, Indinavir sulfate, itraconazole, ketoconazole,
nefazodone, nelfinavir mesylate, ritonavir, telithromycin, troleandomycin).

- Uncontrolled or poorly controlled closed-angle glaucoma, urinary retention, gastric
retention (evaluated from history & physical exam and medical record)

- Hypotension (systolic BP < 80)

- Severe coronary insufficiency, conduction disturbances, recent myocardial infarction
(within past 3 months), cerebrovascular disease, syncope (evaluated from history &
physical and medical record)

- History of allergy or adverse reactions to clonidine or solifenacin

- ECOG status >2 (in bed more than 50% of day)