Table 2.
Group-sequential designs for efficacy or futility assessments in clinical trials with two co-primary endpoints (EP1 and EP2).
| Information time | ||||||
|---|---|---|---|---|---|---|
| Situation | Design No. | Assessment | 1/4 | 1/2 | 3/4 | 1 |
| 1. Futility and efficacy assessments for both endpoints at the same interim analysis: the same interim assessment | #1–1 | Efficacy | Both | Both | Both | Both |
| Futility | Both | Both | Both | Both | ||
| #1–2 | Efficacy | Both | Both | Both | ||
| Futility | Both | Both | Both | |||
| #1–3 | Efficacy | Both | Both | Both | ||
| Futility | Both | Both | Both | |||
| #1–4 | Efficacy | Both | Both | Both | ||
| Futility | Both | Both | Both | |||
| #1–5 | Efficacy | Both | Both | |||
| Futility | Both | Both | ||||
| 2. Futility assessment only conducted at the first interim analysis and then efficacy assessment at later interim analyses: the different interim assessment | #2–1 | Efficacy | Both | Both | Both | |
| Futility | Both | Both | ||||
| #2–2 | Efficacy | Both | Both | |||
| Futility | Both | Both | ||||
| #2–3 | Efficacy | Both | Both | |||
| Futility | Both | Both | ||||
| #2–4 | Efficacy | Both | Both | |||
| Futility | Both | Both | ||||