Table 1.
Drug and Trial Characteristics According to Whether At Least One Expansion Cohort was used in phase 1
| Characteristic | No. of Drugs (%)
|
p | |
|---|---|---|---|
| Not Tested in an Expansion Cohort (Total = 269) | Tested in an Expansion Cohort (Total = 112) | ||
|
| |||
| Publication year of first phase 1 trial | 0.013 | ||
| 2006–2008 | 136 (51) | 41 (37) | |
| 2009–2011 | 133 (49) | 71 (63) | |
| Disease-Specific | 91 (34%) | 48 (43%) | 0.12 |
| Cytotoxic drug class | 68 (25) | 14 (12) | 0.006 |
| Industry sponsorship | 195 (72) | 100 (89) | <0.001 |
| Involvement of multiple centers in a phase 1 trial | 171 (64) | 92 (82) | <0.001 |
| No. of patients in all phase 1 trials | <0.001 | ||
| 5–24 | 122 (45) | 7 (6) | |
| 25–46 | 92 (34) | 35 (31) | |
| 47–289 | 55 (21) | 70 (63) | |
| Malignancy | 0.28 | ||
| Solid tumor | 188 (70) | 70 (62) | |
| Hematologic | 35 (13) | 21 (19) | |
| Mixed | 46 (17) | 21 (19) | |
| Pooled phase 1 response rate | 0.005 | ||
| Not available | 17 (6) | 3 (3) | |
| 0% | 137 (51) | 28 (25) | |
| >0% and <6% | 40 (15) | 34 (30) | |
| ≥6% and <20% | 56 (21) | 29 (26) | |
| ≥20% | 19 (7) | 18 (16) | |
| Pooled grade 3–4 toxic effect rate | 0.24 | ||
| Not available | 18 (7) | 6 (5) | |
| ≥0% and <10% | 146 (54) | 52 (47) | |
| ≥10% and <30% | 61 (23) | 34 (30) | |
| ≥30% | 44 (16) | 20 (18) | |
| Any trial with at least one grade 5 toxic effect | 21 (8) | 23 (21) | <0.001 |
| MTD reached | 133 (49) | 82 (73) | <0.001 |
Abbreviation: MTD, maximum tolerated dose.