Effectiveness of polymer-coated extended-release morphine sulfate capsules in older patients with persistent moderate-to-severe pain: A subgroup analysis of a large, open-label, community-based trial

Background: Opioid analgesics may offer benefits over nonopioids in some older patients, especially those with moderate-to-severe pain. Polymer-coated extended-release morphine sulfate (P-ERMS) has been found to be efficacious and well tolerated in patients with chronic, moderate-to-severe, nonmalignant pain when used QD or BID. Objective: The purpose of this analysis was to determine the effectiveness of P-ERMS in older patients (aged > 65 years) with persistent, moderate-to-severe, inadequately controlled, nonmalignant pain. Methods: This was a subgroup analysis of the older population from an open-label trial in community-based pain clinics in which patients underwent treatment with P-ERMS for persistent, moderate-to-severe, inadequately controlled, nonmalignant pain (>= 4 on a scale of 0-10). Patients received P-ERMS at a dose determined by the investigator based on their previous analgesic regimen, QD (morning or evening) for a 4-week treatment period. Dose increases were permitted after weeks I and 2; switching to BID was allowed after week 2, if needed. Measurements included changes in pain and sleep scores (0-10 scale), quality of life (QOL) scores (physical and mental component summaries [PCS and MCS, respectively] of the 36-Item Short-Form Health Survey instrument), and patient and clinician assessments of current treatment based on a 9-point scale ranging from -4 to 4. Results: One hundred forty-eight older patients (mean [SD] age, 73.4 [5.5] years) began treatment with P-ERMS; 86 (58.1%) of those patients completed the study Pain and sleep scores significantly improved (decreased) from baseline to week 4 (7.4 vs 5.0 and 5.0 vs 3.2, respectively; both, P < 0.001). PCS and MCS scores significantly improved (increased) from baseline (27.7 vs 31.6 and 37.6 vs 40.8, respectively both, P < 0.05), as did patient and clinician global assessments (-1.2 vs 1.1 and -1.5 vs 1.4; both, P < 0.001). Results found in these older patients were similar to those observed in the younger patients (aged : 65 years). A majority (71.4%) of the older patients remained on QD administration and took significantly lower mean daily doses than younger patients (77.0 vs 105.2 mg/d, respectively; P = 0.001). The dropout rate for the subgroup was 4 1.1%, which was similar to that reported in previous studies in mixed-age populations taking other extended-release morphine formulations. Of the patients who discontinued (n = 60), adverse events (AEs) were the most prevalent reason (n = 29). The most common treatment-related AEs were constipation (19.6%) and nausea (9.5%). Conclusions: This subgroup analysis of a previously published study revealed that the older patients in that study who were receiving P-ERMS for persistent, moderate-to-severe, inadequately controlled, nonmalignant pain who completed the study attained significant improvements in pain, sleep, and QOL scores compared with baseline. Patient and clinician satisfaction with treatment increased significantly from baseline to study end. Older patients utilized significantly lower mean daily doses than younger patients (P < 0.001), and > 70% remained on a QD administration regimen for the duration of the study.