EPsProg_multitrial: Expected probability of a successful program for multitrial...

In Sterniii3/drugdevelopR: Utility-Based Optimal Phase II/III Drug Development Planning

Expected probability of a successful program for multitrial programs in a time-to-event setting

Description

These functions calculate the expected probability of a successful program given the parameters. Each function represents a specific strategy, e.g. the function EpsProg3() calculates the expected probability if three phase III trials are performed. The parameter case specifies how many of the trials have to be successful, i.e. how many trials show a significantly relevant positive treatment effect.

Usage

EPsProg2(HRgo, d2, alpha, beta, w, hr1, hr2, id1, id2, case, size, fixed)

EPsProg3(HRgo, d2, alpha, beta, w, hr1, hr2, id1, id2, case, size, fixed)

EPsProg4(HRgo, d2, alpha, beta, w, hr1, hr2, id1, id2, case, size, fixed)

Arguments

HRgo	threshold value for the go/no-go decision rule
d2	total number of events in phase II
alpha	significance level
beta	1-beta power for calculation of sample size for phase III
w	weight for mixture prior distribution
hr1	first assumed true treatment effect on HR scale for prior distribution
hr2	second assumed true treatment effect on HR scale for prior distribution
id1	amount of information for hr1 in terms of number of events
id2	amount of information for hr2 in terms of number of events
case	choose case: "at least 1, 2 or 3 significant trials needed for approval"
size	size category "small", "medium" or "large"
fixed	choose if true treatment effects are fixed or random

Details

The following cases can be investigated by the software:

• Two phase III trials

  • Case 1: Strategy 1/2; at least one trial significant, the treatment effect of the other one at least showing in the same direction

  • Case 2: Strategy 2/2; both trials significant

• Three phase III trials

  • Case 2: Strategy 2/3; at least two trials significant, the treatment effect of the other one at least showing in the same direction

  • Case 3: Strategy 3/3; all trials significant

• Four phase III trials

  • Case 3: Strategy 3/4; at least three trials significant, the treatment effect of the other one at least showing in the same direction

Value

The output of the function EPsProg2(), EPsProg3() and EPsProg4() is the expected probability of a successful program when performing several phase III trials (2, 3 or 4 respectively)

Examples

EPsProg2(HRgo = 0.8, d2 = 50,  alpha = 0.025, beta = 0.1, 
                                 w = 0.3, hr1 =  0.69, hr2 = 0.81, 
                                 id1 = 210, id2 = 420, case = 2, size = "small",
                                 fixed = FALSE)
          EPsProg3(HRgo = 0.8, d2 = 50,  alpha = 0.025, beta = 0.1, 
                                 w = 0.3, hr1 =  0.69, hr2 = 0.81, 
                                 id1 = 210, id2 = 420, case = 2, size = "small",
                                 fixed = TRUE)
          EPsProg4(HRgo = 0.8, d2 = 50,  alpha = 0.025, beta = 0.1, 
                                 w = 0.3, hr1 =  0.69, hr2 = 0.81, 
                                 id1 = 210, id2 = 420, case = 3, size = "small",
                                 fixed = TRUE)

Sterniii3/drugdevelopR documentation built on Jan. 26, 2024, 6:17 a.m.