Table 1.
Disposition and tumor response in biomarker-defined subgroupsa
| Biomarker | Biomarker subset (n=326) |
Tumor response: afatinib versus methotrexate |
||||
|---|---|---|---|---|---|---|
| Afatinib (n=219) | Methotrexate (n=107) | Percentage of total, n/N (%)b | ORR, n (%) | DCR, n (%) | Duration of response, days (range) | |
| p16-positivec | 23 | 12 | 35/234 (15) | 0 (0) versus 1 (8.3) | 11 (47.8) versus 6 (50.0) | NE versus 83 |
| p16-negativec | 135 | 64 | 199/234 (85) | 19 (14.1) versus 1 (1.6) | 69 (51.1) versus 23 (35.9) | 91 (15–233) versus 35 |
| EGFR amplified | 83 | 29 | 112/214 (52) | 11 (13.3) versus 0 (0) | 43 (51.8) versus 10 (34.5) | 107 (41–233) versus NE |
| EGFR not amplified | 67 | 35 | 102/214 (48) | 3 (4.5) versus 0 (0) | 28 (41.8) versus 16 (45.7) | 82 (43–83) versus NE |
| HER3 (H-score ≤50) | 83 | 36 | 119/218 (55) | 9 (10.8) versus 1 (2.8) | 45 (54.2) versus 15 (41.7) | 85 (36–295) versus 83 |
| HER3 (H-score >50) | 67 | 32 | 99/218 (45) | 6 (9.0) versus 0 (0) | 27 (40.3) versus 14 (43.8) | 95 (41–197) versus NE |
| PTEN (H-score ≤150) | 108 | 50 | 158/221 (71) | 14 (13.0) versus 1 (2.0) | 58 (53.7) versus 25 (50.0) | 70 (36–295) versus 83 |
| PTEN (H-score >150) | 43 | 20 | 63/221 (29) | 3 (7.0) versus 0 (0) | 17 (39.5) versus 5 (25.0) | 170 (82–197) versus NE |
| c-MET (H-score ≤75) | 38 | 14 | 52/156 (33) | 3 (7.9) versus 0 (0) | 14 (36.8) versus 4 (28.6) | 42 (36–170) versus NE |
| c-MET (H-score >75) | 73 | 31 | 104/156 (67) | 10 (13.7) versus 0 (0) | 39 (53.4) versus 17 (54.8) | 96 (41–197) versus NE |
| VeriStrat: good | 127d | 70 | 197/303 (65) | 15 (11.8) versus 3 (4.3) | 64 (50.4) versus 30 (43.5) | 120 (36–295) versus 142 (83–144) |
| VeriStrat: poor | 69 | 35 | 104/303 (34) | 7 (10.0) versus 1 (2.9) | 24 (34.3) versus 12 (34.3) | 82 (15–113) versus 35 |
a
In the analysis of HER2 status, 146/161 (91%) patients were reported as HER2 ≤40, and 15/161 (9%) of patients were HER2 >40. Due to the small number of patients with HER2-high expression, further outcomes analyses were not conducted.
b
Percentage based on total patients with specific biomarker available.
c
Based on central test results; includes tumors from all subsites (oropharyngeal and non-oropharyngeal).
d
VeriStrat status was indeterminate for two patients.
DCR, disease control rate; H-score, histology-score; NE, not estimable; ORR, objective response rate.