Table 2.
Exposure and dose modifications
| PIK3CA-mutant cohort N = 127 | PIK3CA-wild-type cohort N = 130 | |||
|---|---|---|---|---|
| Alpelisib + letrozole n = 60 | Placebo + letrozole n = 66 | Alpelisib + letrozole n = 70 | Placebo + letrozole n = 59 | |
| Duration of exposure to study treatment | ||||
| Days, median (Q1–Q3) | 168.0 (102.5–173.0) | 171.0 (168.0–180.0) | 169.0 (165.0–173.0) | 169.0 (167.0–174.0) |
| ≤8 weeks, n (%) | 12 (20.0) | 4 (6.1) | 13 (18.6) | 2 (3.4) |
| >24 weeks, n (%) | 29 (48.3) | 45 (68.2) | 43 (61.4) | 33 (55.9) |
| Duration of exposure to alpelisib/placebo | ||||
| Days, median (Q1–Q3) | 154.0 (30.5–168.0) | 168.0 (167.0–169.0) | 167.0 (43.0–169.0) | 168.0 (166.0–169.0) |
| ≤8 weeks, n (%) | 21 (35.0) | 4 (6.1) | 21 (30.0) | 2 (3.4) |
| >24 weeks, n (%) | 13 (21.7) | 21 (31.8) | 20 (28.6) | 20 (33.9) |
| Dose modifications/discontinuation of alpelisib/placebo, n (%) | ||||
| At least one dose reduction | 34 (56.7) | 3 (4.5) | 35 (50.0) | 2 (3.4) |
| At least one dose interruption | 37 (61.7) | 21 (31.8) | 48 (68.6) | 13 (22.0) |
| Permanent discontinuation reason, n (%) | ||||
| Completed | 28 (46.7) | 60 (90.9) | 40 (57.1) | 47 (79.7) |
| Adverse event | 19 (31.7) | 0 | 18 (25.7) | 2 (3.4) |
| Subject/guardian decision | 7 (11.7) | 1 (1.5) | 7 (10.0) | 2 (3.4) |
| Physician decision | 4 (6.7) | 2 (3.0) | 3 (4.3) | 3 (5.1) |
| Progressive disease | 2 (3.3) | 1 (1.5) | 2 (2.9) | 5 (8.5) |
Abbreviations: Q1, first quartile; Q3, third quartile.