Table 5. Univariate and multivariate analyses of ORR and DCR with first-line afatinib according to clinical and treatment characteristics.
| Characteristics | Objective response | Disease control | |||||||
|---|---|---|---|---|---|---|---|---|---|
| ORR, n (%) | Univariate analysis | Multivariate analysis | DCR, n (%) | Univariate analysis | Multivariate analysis | ||||
| *P value | †OR (95% CI), P value | *P value | †OR (95% CI), P value | ||||||
| EGFR mutation subtype, n (%) | 0.071 | 0.588 | |||||||
| Exon 19 deletion (n=81) | 56 (69.1) | – | 65 (80.2) | – | |||||
| Exon 21 L858R (n=31) | 20 (64.5) | 0.72 (0.29–1.82), 0.490‡ | 25 (80.6) | 1.29 (0.40–4.13), 0.666‡ | |||||
| Resistant mutations (n=4) | 4 (100.0) | – | 4 (100.0) | – | |||||
| Rare and complex mutations (n=17) | 7 (41.2) | 0.27 (0.09–0.85), 0.025‡ | 12 (70.6) | 0.33 (0.09–1.22), 0.096‡ | |||||
| Baseline symptomatic brain metastases, n (%) | 0.423 | 0.163 | |||||||
| No (n=87) | 59 (67.8) | – | 73 (83.9) | – | |||||
| Yes (n=46) | 28 (60.9) | 0.54 (0.22–1.34), 0.184‡ | 33 (71.7) | 0.37 (0.14–0.96), 0.041‡ | |||||
| ECOG performance status, n (%) | 0.096 | 0.142 | |||||||
| 0–1 (n=22) | 11 (50.0) | – | 15 (68.2) | – | |||||
| 2–4 (n=111) | 76 (68.5) | 1.99 (0.69–5.77), 0.205‡ | 91 (82.0) | 2.36 (0.78–7.11), 0.127‡ | |||||
| Tumor stage, n (%) | 0.317 | 0.124 | |||||||
| IVB (n=53) | 37 (69.8) | – | 44 (83.0) | – | |||||
| IVA (n=70) | 42 (60.0) | 0.47 (0.21–1.09), 0.078‡ | 52 (74.3) | 0.41 (0.15–1.10), 0.076‡ | |||||
| IIIC (n=10) | 8 (80.0) | 2.00 (0.35–11.55), 0.436‡ | 10 (100.0) | – | |||||
| Comorbidities, n (%) | 0.984 | 0.672 | |||||||
| No (n=84) | 55 (65.5) | – | 66 (78.6) | – | |||||
| Yes (n=49) | 32 (65.3) | 1.00 (0.43–2.29), 0.993‡ | 40 (81.6) | 1.39 (0.50–3.89), 0.526‡ | |||||
| Afatinib starting dose, n (%) | 0.032 | 0.087 | |||||||
| 40 mg once daily (n=50) | 27 (54.0) | – | 36 (72.0) | – | |||||
| Less than 40 mg once daily (n=83) | 60 (72.3) | 2.64 (1.20–5.83), 0.016‡ | 70 (84.3) | 2.10 (0.77–5.75), 0.149‡ | |||||
| Afatinib dose adjustment, n (%) | 0.158 | 0.881 | |||||||
| No (n=102) | 70 (68.6) | – | 81 (79.4) | – | |||||
| Yes (n=31) | 17 (54.8) | 1.11 (0.43–2.82), 0.833‡ | 25 (80.6) | 2.10 (0.68–6.55), 0.200‡ | |||||
*, P value of Chi-squared test. †, multivariate analysis with cox regression; ‡, the first parameter for each characteristic was the reference group. ORR, objective response rate; DCR, disease control rate; OR, odds ratio; CI, confidence interval; EGFR, epidermal growth factor receptor; ECOG, Eastern Cooperative Oncology Group.