Table 2.
Characteristics of the RECALIB-RET selpercatinib (LIBRETTO-001) and EC (RWD) 1L and ≥2L cohorts of patients with RET-mutation-positive a/mMTC, before and after PSM
| Treatment-naïve cohorts (1L) | ||||||||
|---|---|---|---|---|---|---|---|---|
| Characteristics | Before PSM (unadjusted) |
After PSM (adjusted) |
||||||
| Selpercatinib arm (N = 114)a | EC arm (N = 107) | Std diffb | VRc | Selpercatinib arm (N = 84) | EC arm (N = 84) | Std diffb | VRc | |
| Sex (female) | 44 (38.6) | 27 (25.2) | 0.29 | NA | 24 (28.6) | 27 (32.1) | –0.08 | NA |
| Age at initiation of index LoT (years) | ||||||||
| Number of patients, n | 114 | 107 | — | — | 84 | 84 | — | — |
| Missing, n | 0 | 0 | — | — | 0 | 0 | — | — |
| Mean ± SD | 54.9 ± 15.4 | 57.4 ± 14.0 | –0.17 | 1.2 | 55.6 ± 14.6 | 55.4±14.5 | 0.01 | 1.02 |
| Median (IQR) | NR | 60.0 (49.0-68.0) | — | — | NR | NR | — | — |
| Range | NR | 24.0-84.0 | — | — | NR | NR | — | — |
| Presence of RET M918T mutation | 64 (56.1) | 58 (54.2) | –0.04 | NA | 49 (58.3) | 49 (58.3) | 0.00 | NA |
| Time from initial diagnosis to initiation of index LoT (months) | ||||||||
| Number of patients, n | 114 | 107 | — | — | 84 | 84 | — | — |
| Missing, n | 0 | 0 | — | — | 0 | 0 | — | — |
| Mean ± SD | 101.0 ± 127.5 | 68.3 ± 82.7 | 0.30 | 2.38 | 73.5 ± 97.8 | 67.7 ± 74.8 | 0.05 | 1.71 |
| Median (IQR) | NR | 28.0 (7.0-110.6) | — | — | NR | NR | — | — |
| Range | NR | 0.0-384.2 | — | — | NR | NR | — | — |
| Time from advanced-stage diagnosis to initiation of index LoT (months) | ||||||||
| Number of patients, n | 114 | 107 | — | — | 84 | 84 | — | — |
| Missing, n | 2 | 0 | — | — | 0 | 0 | — | — |
| Mean ± SD | 69.1 ± 100.2 | 28.6 ± 48.3 | 0.52 | 4.3 | 45.4 ± 56.1 | 34.5 ± 52.9 | 0.14 | 1.12 |
| Median (IQR) | 32.4 (5.7-97.3) | 9.4 (3.0-25.2) | — | — | NR | NR | — | — |
| Range | 0.5-593.1 | 0.0-251.3 | — | — | NR | NR | — | — |
| Pretreated cohort (≥2L) | ||||||||
|---|---|---|---|---|---|---|---|---|
| Before PSM (unadjusted) |
After PSM (adjusted) |
|||||||
| Selpercatinib arm (N = 179) | EC arm (N = 51) | Std diffb | VRc | Selpercatinib arm (N = 38) | EC arm (N = 38) | Std diffb | VRc | |
| Sex (female) | 70 (39.1) | 19 (37.3) | 0.04 | NA | 16 (42.1) | 16 (42.1) | 0.00 | NA |
| French (yes) | 25 (14.0) | 30 (58.8) | –1.05 | NA | 14 (36.8) | 17 (44.7) | 0.19 | NA |
| Age at initiation of index LoT (years) | ||||||||
| Number of patients, n | 179 | 51 | — | — | 38 | 38 | — | — |
| Missing, n | 0 | 0 | — | — | 0 | 0 | — | — |
| Mean ± SD | 56.4 ± 15.0 | 53.4 ± 14.0 | 0.21 | 1.16 | 53.3 ± 16.1 | 54.4 ± 14.5 | –0.08 | 1.24 |
| Median (IQR) | 58.0 (47.0-67.0) | 55.0 (39.0-65.0) | — | — | NR | NR | — | — |
| Range | 17.0-90.0 | 29.0-77.0 | — | — | NR | NR | — | — |
| Number of prior lines of therapy received before the index LoT | ||||||||
| Number of patients, n | 179 | 51 | — | — | 38 | 38 | — | — |
| Missing, n | 0 | 0 | — | — | 0 | 0 | — | — |
| Mean ± SD | 1.9 ± 1.3 | 1.3 ± 0.5 | 0.61 | 6.18 | 1.3 ± 0.5 | 1.3 ± 0.6 | 0.00 | 0.68 |
| Median (IQR) | 1.0 (1.0-2.0) | 1.0 (1.0-2.0) | — | — | NR | NR | — | — |
| Range | 1.0-8.0 | 1.0-3.0 | — | — | NR | NR | — | — |
| Duration of prior line relative to the median (8.9 months) | ||||||||
| ≥Median | 86 (48.0) | 22 (43.1) | 0.10 | NA | 19 (50.0) | 17 (44.7) | –0.11 | NA |
| <Median | 81 (45.3) | 27 (52.9) | –0.15 | NA | 19 (50.0) | 19 (50.0) | 0.00 | NA |
| Time from advanced diagnosis to initiation of index LoT (months) | ||||||||
| Number of patients, n | 179 | 51 | — | — | 38 | 38 | — | — |
| Missing, n | 0 | 0 | — | — | 0 | 0 | — | — |
| Mean ± SD | 76.9 ± 67.6 | 46.2 ± 53.3 | 0.51 | 1.61 | 50.9 ± 43.3 | 48.3 ± 57.7 | 0.04 | 0.56 |
| Median (IQR) | 55.8 (29.9-106.3) | 31.5 (11.5-59.0) | — | — | NR | NR | — | — |
| Range | 0.5-341.5 | 0.7-318.6 | — | — | NR | NR | — | — |
| Cabozantinib exposure before index LoT | 83 (46.4) | 7 (13.7) | 0.76 | NA | 8 (21.1) | 7 (18.4) | –0.06 | NA |
| Vandetanib exposure before index LoT | 120 (67.0) | 38 (74.5) | –0.16 | NA | 30 (78.9) | 30 (78.9) | 0.00 | NA |
| Other MKI exposure before index LoT | 41 (22.9) | 7 (13.7) | 0.24 | NA | 4 (10.5) | 5 (13.2) | 0.07 | NA |
| Chemotherapy exposure before index LoT | 21 (11.7) | 8 (15.7) | –0.12 | NA | 5 (13.2) | 4 (10.5) | –0.08 | NA |
| PD as best response to treatment immediately before index LoT | 42 (23.5) | 10 (19.6) | 0.09 | NA | 9 (23.7) | 7 (18.4) | –0.13 | NA |
Data are n (%) unless stated otherwise.
1L, first line; ≥2L, second and later line; a/m, advanced/metastatic; EC, external control arm; IQR, interquartile range; LoT, line of therapy; MKI, multikinase inhibitor; MTC, medullary thyroid cancer; NA, not available; NR, not reported; PD, progressive disease; PSM, propensity score matching; RET, gene encoding rearranged during transfection protein; RWD, real-world data; SD, standard deviation; std diff, standard difference; VR, variance ratio.
Two patients were excluded from this analysis due to missing time from advanced diagnosis to initiation of index LoT.
Standard difference is the difference in means between groups divided by a measure of SD; values close to 0 indicate better balance.
Variance ratio closer to 1 indicates better balance.