Table 1.
Demographics and baseline characteristics
| Characteristics | RCT
|
OLT | |||
|---|---|---|---|---|---|
| Double-blind phase
|
Open-label phase
|
||||
| Methylnaltrexone 12 mg qd (n=150) | Methylnaltrexone 12 mg qod (n=148) | Placebo (n=162) | Methylnaltrexone 12 mg prn (n=364) | Methylnaltrexone 12 mg prn (n=1,034) | |
| Mean age, yr (range) | 48.0 (24 to 78) | 48.6 (23 to 73) | 49.7 (25 to 83) | 49.54 (23 to 83) | 51.7 (23 to 81) |
| Female, n (%) | 93 (62.0) | 85 (57.4) | 99 (61.1) | 220 (60.4) | 669 (64.7) |
| Race, n (%) | |||||
| White | 139 (92.7) | 133 (89.9) | 141 (87.0) | 331 (90.9) | 927 (89.7) |
| Black | 7 (4.7) | 10 (6.8) | 15 (9.3) | 23 (6.3) | 76 (7.4) |
| Other | 4 (2.7) | 5 (3.4) | 6 (3.7) | 10 (2.7) | 31 (3.0) |
| Primary pain condition, n (%) | |||||
| Back pain | 96 (64.0) | 83 (56.1) | 99 (66.1) | 219 (60.2) | 556 (53.8) |
| Cervical/neck pain | 6 (4.0) | 10 (6.8) | 5 (3.1) | 17 (4.7) | 67 (6.5) |
| Fibromyalgia syndrome | 13 (8.7) | 9 (6.1) | 8 (4.9) | 26 (7.1) | 75 (7.3) |
| Neuropathic pain | 4 (2.7) | 11 (7.4) | 6 (3.7) | 16 (4.4) | 51 (4.9) |
| Osteoarthritis | 12 (8.0) | 11 (7.4) | 13 (8.0) | 30 (8.2) | 112 (10.8) |
| Rheumatoid arthritis | 2 (1.3) | 3 (2.0) | 2 (1.2) | 5 (1.4) | 22 (2.1) |
| Complex regional pain syndrome | 3 (2.0) | 0 | 2 (1.2) | 4 (1.1) | 1 (0.1) |
| Lower extremity/hip pain | 4 (2.7) | 10 (6.8) | 9 (5.6) | 18 (4.9) | – |
| Migraines/headaches | 2 (1.3) | 1 (0.7) | 1 (0.6) | 3 (0.8) | – |
| Pelvic pain | 1 (0.7) | 0 | 4 (2.5) | 5 (1.4) | 1 (0.1) |
| Trigeminal neuralgia | 1 (0.7) | 0 | 1 (0.6) | 1 (0.3) | 0 |
| Upper extremity/shoulder pain | 2 (1.3) | 2 (1.4) | 3 (1.9) | 5 (1.4) | – |
| Other | 4 (2.7) | 8 (5.4) | 9 (5.6) | 15 (4.1) | 149 (14.4) |
| Median morphine equivalent dose, mg/d (range) | 161.0 (45.5 to 831.2) | 154.8 (7.2 to 1,334.3) | 160.8 (13.6 to 1,286.5) | 163.4 (7.15 to 1,334.3) | 120.0 (1.2 to 2,196.0) |
| Mean pain intensity score (SD) | 6.2 (1.9) | 6.3 (1.9) | 6.3 (1.7) | 6.3 (1.8) | 6.1 |
Note: Adapted from Michna E, Blonsky ER, Schulman S, et al. Subcutaneous methylnal trexone for treatment of opioid-induced constipation in patients with chronic, nonmalignant pain: a randomized controlled study. J Pain. 2011;12(5):554–562.13 Copyright © 2011, with permission from Elsevier. Additional study data was also used.
Abbreviations: d, day; OLT, open-label trial; prn, as needed; qd, once daily; qod, every other day; RCT, randomized controlled trial; SD, standard deviation; yr, years.