TABLE 2.
Model selection for the time-to-event analysis.
| Overall survival | Progression-free survival | |||
|---|---|---|---|---|
| Model description | OFV | ΔOFV | OFV | ΔOFV |
| Base model (no covariate) | 709.412 | — | 991.293 | — |
| +Age | 709.283 | −0.129 | 990.845 | −0.448 |
| +Sex | 707.685 | −1.727 | 988.308 | −2.985 |
| +Race | 705.362 | −4.05 | 991.050 | −0.243 |
| +Weight | 700.456 | −8.956* | 988.471 | −2.822 |
| +BMI | 701.799 | −7.613* | 987.978 | −3.315 |
| +Region | 708.651 | −0.761 | 987.905 | −3.388 |
| +Country groups | 704.252 | −5.16 | 987.903 | −3.390 |
| +Smoking status | 709.373 | −0.065 | 990.720 | −0.573 |
| +Cancer type | 709.412 | 0 | 988.921 | −2.372 |
| +Baseline ECOG | 708.724 | −0.688 | 988.196 | −3.097 |
| +Concentrations | 689.951 | −19.461* | 982.600 | −8.693* |
| +Overall ADA by cycle 7 | 709.248 | −0.164 | 990.475 | −0.818 |
| +Overall ADA by EOT | 707.670 | −1.742 | 990.571 | −0.722 |
| +Treatment (SB8 vs. EU Avastin®) | 709.347 | −0.065 | 991.288 | −0.005 |
| New base model (with concentrations) | 689.951 | — | ||
| +Weight | 684.632 | −5.319 | ||
| +BMI | 685.536 | −4.415 | ||
| +Concentrations** | 689.951 | −19.461*** | 982.600 | −8.693*** |
A stepwise addition (p = 0.01, ΔOFV = −6.63) and elimination (p = 0.005, ΔOFV = −7.88) method was applied in the selection of covariates.
*Covariate showing statistical significance based on p= 0.01 (ΔOFV = −6.63) in the univariate analysis.
**The final models for overall survival and progression-free survival.
***–19.461 is the difference in objective function values between the base model for overall survival and the final model with concentrations, and −8.693 is the difference in objective function values between the base model for progression-free survival and the final model with concentrations.
BMI, body mass index; OFV, objective function value; ΔOFV, change in the OFV relative to the preceding model; ADA, anti-drug antibody; ECOG, Eastern Cooperative Oncology Group; EOT, end of treatment; EU, European Union.