Table 3.
Comparison of Augmentation, Average Daily Dose, Discontinuation, and Switching in Depressive Patients Treated with Brand-Name and Generic Formula of 10 Antidepressants
| Antidepressant | Group | Subgroup | Augmentation aHR (95% CI) | Dose, mg/day mean ± SD | Ratio, Dose/DDD | Discontinuation aHR (95% CI)c | Switching aHR (95% CI)a |
|---|---|---|---|---|---|---|---|
| Fluoxetine | DD | Brand-name | 1.00 [Reference] | 21.62 ± 10.82 | 1.08 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | .91 (.89–.93)*** b | 22.62 ± 11.42 | 1.13*** c | 1.00 (.99–1.01) | .93 (.90–.95)*** b | ||
| MDD | Brand-name | 1.00 [Reference] | 22.97 ± 12.50 | 1.15 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | .93 (.90–.96)*** b | 23.68 ± 10.91 | 1.18*** c | .99 (.97–1.00) | .89 (.86–.93)*** b | ||
| Sertraline | DD | Brand-name | 1.00 [Reference] | 51.20 ± 27.12 | 1.02 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | 1.10 (1.07–1.13)*** c | 49.00 ± 23.61 | .98*** b | 1.06 (1.04–1.07)*** c | 1.07 (1.04–1.10)*** c | ||
| MDD | Brand-name | 1.00 [Reference] | 56.04 ± 30.47 | 1.12 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | 1.11 (1.07–1.16)*** c | 54.94 ± 26.24 | 1.10*** b | 1.06 (1.03–1.09)*** c | .93 (.89–.98)* b | ||
| Paroxetine | DD | Brand-name | 1.00 [Reference] | 17.65 ± 8.88 | .88 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | 1.01 (.98–1.04) | 17.98 ± 8.42 | .90*** c | 1.05 (1.03–1.07)*** c | 1.02 (.98–1.05) | ||
| MDD | Brand-name | 1.00 [Reference] | 19.54 ± 12.01 | .98 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | .97 (.92–1.01) | 20.59 ± 9.10 | 1.03** c | 1.00 (.97–1.04) | .96 (.91–1.02) | ||
| Escitalopram | DD | Brand-name | 1.00 [Reference] | 9.30 ± 4.37 | .93 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | .89 (.86–.92)*** b | 9.50 ± 4.16 | .95*** c | 1.02 (1.00–1.05) | .91 (.86–.95)*** b | ||
| MDD | Brand-name | 1.00 [Reference] | 10.16 ± 4.70 | 1.02 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | .84 (.79–.89)*** b | 10.86 ± 4.58 | 1.09*** c | .98 (.94–1.02) | .90 (.84–.97)* b | ||
| Citalopram | DD | Brand-name | 1.00 [Reference] | 19.21 ± 9.19 | .96 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | .92 (.89–.95)*** b | 18.42 ± 8.35 | .92*** b | .93 (.91–.95)*** b | .85 (.81–.88)*** b | ||
| MDD | Brand-name | 1.00 [Reference] | 20.74 ± 9.75 | 1.04 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | .96 (.91–1.01) | 20.58 ± 9.97 | 1.03* b | .92 (.89–.95)*** b | .87 (.81–.92)*** b | ||
| Venlafaxine | DD | Brand-name | 1.00 [Reference] | 85.00 ± 44.73 | .85 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | .98 (.94–1.03) | 77.04 ± 41.69 | .77*** b | 1.01 (.98–1.04) | 1.05 (1.00–1.11)* c | ||
| MDD | Brand-name | 1.00 [Reference] | 96.27 ± 57.46 | .96 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | .83 (.78–.88)*** b | 93.39 ± 45.94 | .93*** b | .91 (.87–.95)*** b | .98 (.91–1.06) | ||
| Mirtazapine | DD | Brand-name | 1.00 [Reference] | 28.19 ± 13.42 | .94 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | .96 (.92–1.00) | 24.46 ± 11.54 | .82*** b | .94 (.92–.97)** b | .91 (.86–.96)** b | ||
| MDD | Brand-name | 1.00 [Reference] | 30.45 ± 15.42 | 1.01 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | .96 (.90–1.03) | 27.64 ± 12.57 | .92*** b | .94 (.90–.98)* b | .88 (.81–.95)* b | ||
| Moclobemide | DD | Brand-name | 1.00 [Reference] | 312.08 ± 144.88 | 1.04 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | .93 (.87–.98)* b | 277.04 ± 127.13 | .92*** b | 1.01 (.98–1.05) | .87 (.82–.94)** b | ||
| MDD | Brand-name | 1.00 [Reference] | 350.00 ± 295.56 | 1.17 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | .96 (.87–1.06) | 326.79 ± 134.63 | 1.09*** b | .97 (.91–1.04) | .95 (.85–1.07) | ||
| Imipramine | DD | Brand-name | 1.00 [Reference] | 29.80 ± 24.68 | .30 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | .85 (.81–.89)*** b | 39.51 ± 28.17 | .40*** c | .97 (.94–.99)* b | .90 (.86–.95)*** b | ||
| MDD | Brand-name | 1.00 [Reference] | 41.94 ± 41.41 | .42 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | 1.05 (.95–1.15) | 45.90 ± 37.58 | .46*** c | 1.12 (1.05–1.19)** c | 1.06 (.95–1.18) | ||
| Bupropion | DD | Brand-name | 1.00 [Reference] | 185.60 ± 79.71 | .62 | 1.00 [Reference] | 1.00 [Reference] |
| Generic | .96 (.88–1.04) | 168.31 ± 68.56 | .56*** b | 1.03 (.98–1.08) | 1.02 (.93–1.12) | ||
| MDD | Brand-name | 1.00 [Reference] | 200.76 ± 86.54 | .67 | 1.00 [Reference] | 1.00 [Reference] | |
| Generic | 1.02 (.90–1.15) | 185.86 ± 80.31 | .62*** b | .99 (.91–1.09) | .89 (.76–1.05) |
*P < .05; **P < .001; ***P < .0001.
Abbreviations: aHR, adjusted hazard ratio; CI: confidence interval; DD, depressive disorders; DDD, defined daily dose; MDD, major depressive disorders; SD, standard deviation.
aAdjusted for gender, age, entry year, Charlson Comorbidity Index, substance use disorders, anxiety disorders, sleep disorders, benzodiazepines use, monthly income, and medical institution.
bDrug-B data are significantly higher than drug-G data.
cDrug-G data are significantly higher than drug-B data.