Olanzapine for Reducing Opioid Craving and Misuse among Patients Receiving Opioids for Cancer-related Pain

PRIMARY OBJECTIVE:

I. To determine the effect of olanzapine on opioid craving among patients receiving opioids for cancer pain (Opioid Craving Scale; Opioid Craving Visual Analogue Scale, change from baseline).

SECONDARY OBJECTIVE:

I. To determine the effect of olanzapine on opioid misuse among patients receiving opioids for cancer pain (Current Opioid Misuse Measure, change from baseline).

EXPLORATORY OBJECTIVES:

I. To estimate the effect of olanzapine and placebo on the amount of opioid use among patients receiving opioids for cancer pain (morphine equivalent daily dose).

II. To determine the effect of olanzapine and placebo on pain intensity among patients receiving opioids for cancer pain (Brief Pain Inventory).

III. To determine the effect of olanzapine and placebo on overall symptom burden among patients receiving opioids for cancer pain (Edmonton Symptom Assessment Scale [ESAS] symptom Distress Score).

IV. To estimate the differences between the olanzapine and placebo effects on opioid craving and misuse measures (Opioid Craving Scale, Opioid Craving Visual Analogue Scale, Current Opioid Misuse Measure).

V. To determine the adverse effects of olanzapine and placebo among patients receiving opioids for cancer pain (National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0).

OUTLINE: Patients are randomized to 1 of 3 arms.

ARM I: Patients receive a lower dose of olanzapine orally (PO) once daily (QD) on days 1-7 and then a higher dose of olanzapine PO on days 8-30 in the absence of disease progression or unacceptable toxicity.

ARM II: Patients receive a lower dose of olanzapine PO QD on days 1-30 in the absence of disease progression or unacceptable toxicity.

ARM III: Patients receive placebo PO QD on days 1-30 in the absence of disease progression or unacceptable toxicity.