This is a Phase II to Phase III randomized, double-blind, placebo-controlled design to determine if duloxetine can prevent oxaliplatin-induced peripheral neuropathy (OPIN). Initially, we will screen two duloxetine doses, 30 mg and 60 mg daily, using a 3-arm Phase II study design. The most promising dose will then be tested in a 2-arm Phase III study. The primary hypothesis in the Phase III study is that the most promising duloxetine dose will be more effective than placebo to prevent 1) sensory OIPN (N, T, & pain) during treatment and 2) chronic OIPN pain 1 month after the last planned oxaliplatin treatment.
- Stage II-III colorectal cancer patients scheduled to receive oxaliplatin 510 mg/m² (cumulative dose) over 12 weeks as a component of adjuvant FOLFOX treatment, in which patients are scheduled to receive oxaliplatin 85 mg/m² every 2 weeks for 12 weeks (i.e., 6 cycles), or adjuvant CAPOX treatment, in which patients are scheduled to receive oxaliplatin 135 mg/m² every 3 weeks for 12 weeks (i.e., 4 cycles).
- No pre-existing clinical or pre-clinical peripheral neuropathy from any cause.
- Not pregnant and not nursing, because this study involves an investigational agent whose genotoxic, mutagenic and teratogenic effects on the developing fetus and newborn are unknown.
- Comorbid conditions: Patients with the following comorbid conditions are not eligible:
- History of seizure disorder
- Narrow-angle glaucoma
- History of suicidal thoughts
- Symptoms of or a history of schizophrenia, bipolar disease, and/or major depression
- A serious eating disorder such as bulimia or anorexia
- Known diagnosis of alcohol addiction/dependence within the past 10 years
- Chronic concomitant treatment with drugs that are extensively metabolized by CYP2D6 and that have a narrow therapeutic index, including certain antidepressants, phenothiazines, and Type 1C antiarrhythmics should be approached with caution.
- In order to complete the mandatory patient-completed measure, patients must be able to speak and read English.
If you join the study, you will have more exams, tests, and procedures to closely monitor your safety and health. Most of these are included in the usual care you would get even if you were not in a study.
You will be asked to fill out forms with questions about OIPN symptoms, for example, numbness or tingling, any OIPN pain you feel, or if OIPN makes doing your usual activities more difficult. Researchers will use this information to learn if duloxetine prevents OIPN.
You will be asked to fill out these forms based on the frequency of your oxaliplatin treatment, which may be either every 2 weeks or every 3 weeks. These 2- or 3-week time periods are also known as “cycles.” You will be asked to fill out the forms:
- On Days 1-6 of every cycle of your oxaliplatin treatment for 12 weeks
- Daily for one month after your last oxaliplatin treatment (takes less than 1 minute to complete)
- At 3, 6, 12 and 18 months after your last oxaliplatin treatment.
You will also be asked to record in a diary when you taking your study medication every day for 17 weeks and bring back your medication bottle, so that your study staff can count the number of capsules you have taken.