Table 2. Outcome incidence rates for patients initiating authorized generics (AGs) versus generics, and patients switching from brand-name products to AGs versus generics, after 1:1 propensity score matching in each database.
| Characteristic | Optum | MarketScan | ||||||
|---|---|---|---|---|---|---|---|---|
| Patients initiating AGs | Patients initiating generics | Patients switching from brand-name to AGs | Patients switching from brand-name to generics | Patients initiating AGs | Patients initiating generics | Patients switching from brand-name to AGs | Patients switching from brand-name to generics | |
| Alendronate | ||||||||
| Sample size | 2,433 | 2,433 | 6,332 | 6,332 | 11,963 | 11,963 | 29,985 | 29,985 |
| Total person-years | 626 | 1,602 | 2,378 | 6,212 | 3,069 | 8,540 | 11,406 | 29,819 |
| n fracture events | 11 | 13 | 33 | 65 | 49 | 125 | 164 | 412 |
| Incidence rate/1,000 py | 17.57 | 8.11 | 13.88 | 10.46 | 15.97 | 14.64 | 14.38 | 13.82 |
| Incidence rate difference (95% CI) | 9.46 (−1.82, 20.74) | Ref | 3.42 (−1.96, 8.79) | Ref | 1.33 (−3.83, 6.48) | Ref | 0.56 (−2.01, 3.14) | Ref |
| Amlodipine | ||||||||
| Sample size | 73,853 | 73,853 | 35,004 | 35,004 | 461,045 | 461,045 | 116,521 | 116,521 |
| Total person-years | 46,443 | 47,776 | 35,451 | 41,324 | 328,747 | 306,866 | 133,303 | 134,765 |
| n composite cardiovascular endpoint events | 925 | 939 | 601 | 668 | 6,531 | 6,125 | 2,370 | 2,616 |
| Incidence rate/1,000 py | 19.92 | 19.65 | 16.95 | 16.17 | 19.87 | 19.96 | 17.78 | 19.41 |
| Incidence rate difference (95% CI) | 0.26 (−1.53, 2.06) | Ref | 0.79 (−1.04, 2.62) | Ref | −0.09 (−0.79, 0.60) | Ref | −1.63 (−2.66, −0.60) | Ref |
| Amlodipine-benazepril | ||||||||
| Sample size | 10,941 | 10,941 | 6,034 | 6,034 | 47,375 | 47,375 | 29,652 | 29,652 |
| Total person-years | 5,866 | 8,213 | 4,446 | 5,790 | 25,821 | 42,414 | 24,656 | 34,162 |
| n composite cardiovascular endpoint events | 104 | 99 | 49 | 50 | 316 | 427 | 263 | 398 |
| Incidence rate/1,000 py | 17.73 | 12.05 | 11.02 | 8.64 | 12.24 | 10.07 | 10.67 | 11.65 |
| Incidence rate difference (95% CI) | 5.67 (1.52, 9.83) | Ref | 2.39 (−1.52, 6.29) | Ref | 2.17 (0.52, 3.82) | Ref | −0.98 (−2.71, 0.74) | Ref |
| Calcitonin salmon | ||||||||
| Sample size | 1,054 | 1,054 | 458 | 458 | 7,420 | 7,420 | 2,892 | 2,892 |
| Total person-years | 251 | 303 | 223 | 237 | 1,737 | 2,300 | 1,335 | 1,511 |
| n fracture events | 16 | 15 | 4 | 2 | 129 | 116 | 43 | 41 |
| Incidence rate/1,000 py | 63.71 | 49.46 | 17.92 | 8.44 | 74.26 | 50.44 | 32.22 | 27.13 |
| Incidence rate difference (95% CI) | 14.25 (−25.76, 54.27) | Ref | 9.48 (−11.62, 30.58) | Ref | 23.82 (8.06, 39.59) | Ref | 5.09 (−7.62, 17.81) | Ref |
| Escitalopram | ||||||||
| Sample size | 24,445 | 24,445 | 12,693 | 12,693 | 127,803 | 127,803 | 134,298 | 134,298 |
| Total person-years | 6,492 | 7,698 | 6,187 | 6,453 | 39,229 | 57,741 | 60,221 | 107,489 |
| n psychiatric hospitalizations | 323 | 356 | 85 | 100 | 1,429 | 1,766 | 595 | 936 |
| Incidence rate/1,000 py | 49.75 | 46.25 | 13.74 | 15.50 | 36.43 | 30.58 | 9.88 | 8.71 |
| Incidence rate difference (95% CI) | 3.50 (−3.74, 10.75) | Ref | −1.76 (−5.97, 2.46) | Ref | 5.84 (3.48, 8.21) | Ref | 1.17 (0.20, 2.14) | Ref |
| Glipizide | ||||||||
| Sample size | 2,193 | 2,193 | 723 | 723 | 66,713 | 66,713 | ||
| Total person-years | 1,745 | 1,719 | 553 | 576 | 44,940 | 42,077 | 2,470 | 2,473 |
| n insulin initiations | 122 | 94 | 34 | 29 | 3,869 | 3,088 | 159 | 119 |
| Incidence rate/1,000 py | 69.92 | 54.70 | 61.44 | 50.36 | 86.09 | 73.39 | 64.40 | 48.10 |
| Incidence rate difference (95% CI) | 15.23 (−1.39, 31.85) | Ref | 11.08 (−16.53, 38.69) | Ref | 12.70 (8.95, 16.45) | Ref | 16.30 (3.00, 29.50) | Ref |
| Quinapril | ||||||||
| Sample size | 8,335 | 8,335 | 14,369 | 14,369 | 32,074 | 32,074 | 25,766 | 25,766 |
| Total person-years | 5,476 | 4,352 | 14,797 | 11,893 | 22,580 | 19,778 | 35,060 | 22,057 |
| n composite cardiovascular endpoint events | 121 | 121 | 286 | 216 | 491 | 389 | 582 | 356 |
| Incidence rate/1,000 py | 22.10 | 27.80 | 19.33 | 18.16 | 21.74 | 19.67 | 16.60 | 16.14 |
| Incidence rate difference (95% CI) | −5.70 (−12.03, 0.62) | Ref | 1.17 (−2.13, 4.46) | Ref | 2.08 (−0.67, 4.82) | Ref | 0.46 (−1.69, 2.61) | Ref |
| Sertraline | ||||||||
| Sample size | 177,959 | 177,959 | 48,019 | 48,019 | 639,272 | 639,272 | 107,150 | 107,150 |
| Total person-years | 71,333 | 77,623 | 32,544 | 33,825 | 260,109 | 314,073 | 72,249 | 88,924 |
| n psychiatric hospitalizations | 2,554 | 2,546 | 308 | 274 | 8,437 | 8,637 | 576 | 624 |
| Incidence rate/1,000 py | 35.80 | 32.80 | 9.46 | 8.10 | 32.44 | 27.50 | 7.97 | 7.02 |
| Incidence rate difference (95% CI) | 3.00 (1.12, 4.89) | Ref | 1.36 (−0.06, 2.79) | Ref | 4.94 (4.03, 5.84) | Ref | 0.96 (0.10, 1.81) | Ref |
CI, confidence interval; py, person-years.