Table 3. Characteristics of studies used to support FDA lung cancer approvals (2006 to 2018) made via the accelerated vs regular pathways and BTD vs non-BTD.
| Study characteristics | Accelerated vs regular pathways | Breakthrough therapy designation (BTD) vs non-BTD | ||||||
|---|---|---|---|---|---|---|---|---|
| Accelerated pathway | Regular pathway | Prevalence ratio (95%CI) | p-value | BTD (%) | Non-BTD (%) | Prevalence ratio (95%CI) | p-value | |
| n (%) | n (%) | |||||||
| Study design | ||||||||
| Single-arm | 11 (85) | 5 (21) | 4.06 (1.80–9.16) | < .001 | 10 (62) | 4 (25) | 2.50 (0.99–6.33) | 0.073 |
| RCT | 2 (15) | 19 (79) | 6 (38) | 12 (75) | ||||
| Outcome type | ||||||||
| Surrogate endpoint | 12 (92) | 14 (58) | 1.58 (1.09–2.30) | 0.057 | 13 (81) | 10 (62) | 1.30 (0.83–2.30) | 0.43 |
| Overall survival | 1 (8) | 10 (42) | 3 (19) | 6 (38) | ||||
| Sample size | ||||||||
| <200 | 9 (69) | 7 (29) | 2.37 (1.15–4.88) | 0.036 | 9 (56) | 9 (56) | 2.37 (0.54–1.84) | 1.0 |
| ≥200 | 4 (31) | 17 (71) | 7 (44) | 7 (44) | ||||
| Effect size | ||||||||
| Large | 5 (38) | 6 (25) | 1.54 (0.58–4.08) | 0.27 | 7 (44) | 2 (13) | 3.50 (0.85–14.34) | 0.11 |
| Not large | 8 (62) | 18 (75) | 9 (56) | 14 (87) | ||||