Methadone to Treat Painful Chemotherapy Induced Peripheral Neuropathy

"The treatment arm will take methadone 2 mg PO q8h and a placebo called placeboD PO qdaily. PlaceboD and duloxetine will be placed in capsules to be virtually indistinguishable.~Participants will be followed (televisit or in-person) by assessors every week; this will take approximately 15 minutes. This includes review of questionnaire(s), adverse events (and any potential management), and recommendations on dose titration. To maintain blinding and ensure standardization across assessors, titration protocols will be provided. If pain is not controlled, the assessors will instruct the participant to increase their methadone/placeboM drug by 1 capsule PO q8h and their duloxetine/placeboD drug to 2 capsules PO qdaily (the study maximum). If there are poorly tolerated adverse events the dose will be reduced to the previously tolerated dose, and then the following week they may attempt to titrate up again per the above protocol."

"The control arm will receive duloxetine 30 mg PO qdaily, and a placebo called placeboM PO q8h. PlaceboM and methadone will be placed in capsules to be virtually indistinguishable.~Participants will be followed (televisit or in-person) by assessors every week; this will take approximately 15 minutes. This includes review of questionnaire(s), adverse events (and any potential management), and recommendations on dose titration. To maintain blinding and ensure standardization across assessors, titration protocols will be provided. If pain is not controlled, the assessors will instruct the participant to increase their methadone/placeboM drug by 1 capsule PO q8h and their duloxetine/placeboD drug to 2 capsules PO qdaily (the study maximum). If there are poorly tolerated adverse events the dose will be reduced to the previously tolerated dose, and then the following week they may attempt to titrate up again per the above protocol."