Table 2.
Patient disposition and dose intensity for the study treatment
| All patients during day 1 to day 180 | Standard dose (n = 10) | Dose escalation (n = 15) | P value |
|---|---|---|---|
| Interruption, n (%) | 9 (90.0%) | 2 (13.3%) | < 0.001 |
| Diarrhea | 9 (90.0%) | 0 (0.0%) | |
| Liver dysfunctions | 5 (50.0%) | 2 (13.3%) | |
| Skin rash | 2 (20.0%) | 0 (0.0%) | |
| Cytopenia | 3 (30.0%) | 0 (0.0%) | |
| Elevation of lipase | 1 (10.0%) | 0 (0.0%) | |
| Median (range) day to the first interruption of bosutinib | 17.5 (8–180) | 180 (35–180) | < 0.001 |
| Total median (range) duration of treatment interruption (days) | 35 (8–81) | 14 (14–14) | 0.013 |
| Dose reduction, n (%) | 8 (80.0%) | 8 (53.3%) | 0.182 |
| Discontinuation of treatment, n (%) | 3 (30.0%) | 1 (6.6%) | 0.127 |
| Adverse events | 2 (20.0%)a | 1 (6.6%) | |
| Progression disease | 1 (10.0%) | 0 (0.0%) |
| On day 180 after beginning therapy | Standard dose (n = 7) | Dose escalation (n = 14) | P value |
|---|---|---|---|
| Final dose: 100/200/300/400/500 mg QD, n | 0/0/5/1/1 (mean 343 mg/day) | 1/2/4/4/3 (mean 346 mg/day) | 0.403 |
| Median (range) duration of administration (days) | 157.0 (99–180) | 180.0 (166–180) | < 0.001 |
| Median (range) cumulative dose for 6 months (mg) | 51,700 (32,800–90,000) | 53,550 (29,700–75,600) | 1.000 |
| Median (range) dose intensity of bosutinib (mg/day) | 309.8 (182.2–500.0) | 295.0 (165.0–420.0) | 1.000 |
| Median (range) plasma trough concentration (ng/mL) | 63.7 (31.9–126.0) (mean = 75.1) | 63.0 (31.4–113.0) (mean = 65.8) | 0.588 |
aTwo patients discontinued bosutinib due to pancytopenia (n = 1) and elevation of lipase (n = 1)