This post-authorization observational safety study determines the characteristics of patients prescribed naloxegol at time of first prescription and treatment patterns of naloxegol in follow-up in the United Kingdom (UK), Norway, Sweden, and Germany.

The overall research questions for this study are: 1) What are the demographic, clinical, and treatment characteristics (including dose) at baseline of patients prescribed naloxegol in real-world practice (including the use of naloxegol in non-indicated populations)? and 2) What are the treatment patterns of naloxegol utilization during follow-up?

Primary objectives:

1. To describe the characteristics of patients prescribed naloxegol at time of first prescription (demographics, targeted comorbidities, targeted comedications, provider characteristics, and indication characteristics).

2. To describe any of the following treatment patterns:

   • Discontinuation of naloxegol (permanently during the observation period)
   • Switching from naloxegol to other drug(s) potentially used by patients with opioid induced constipation (OIC)
   • Prescription of other drug(s) potentially used by patients with OIC in the same period when naloxegol is prescribed (augmentation)
   • Restart in the prescription of naloxegol (after temporary discontinuation or treatment holiday)
   • Continuous treatment with naloxegol during the study period
   • Change in dosing

Exploratory objective:

1. To identify predictors of length of naloxegol use

Inclusion Criteria:

1. The patient has at least 1 prescription of naloxegol in his/her medical record anytime during the study period.
2. The patient has at least 12 months of computerized records prior to the first prescription of naloxegol (index date)

Exclusion Criteria:

• No exclusion criteria will be applied

Patients in the targeted countries who are newly prescribed naloxegol will be identified for inclusion. Patients analyzed in this study will be those who have at least 12 months of continuous data available prior to first prescription. The number of patients who do not have at least 12 months of prior data will be reported for completeness.