EPsProg_multitrial_binary: 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 with binary distributed outcomes

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_binary() 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_binary(
  RRgo,
  n2,
  alpha,
  beta,
  p0,
  w,
  p11,
  p12,
  in1,
  in2,
  case,
  size,
  fixed
)

EPsProg3_binary(
  RRgo,
  n2,
  alpha,
  beta,
  p0,
  w,
  p11,
  p12,
  in1,
  in2,
  case,
  size,
  fixed
)

EPsProg4_binary(
  RRgo,
  n2,
  alpha,
  beta,
  p0,
  w,
  p11,
  p12,
  in1,
  in2,
  case,
  size,
  fixed
)

Arguments

RRgo	threshold value for the go/no-go decision rule
n2	total sample size for phase II; must be even number
alpha	significance level
beta	1-beta power for calculation of sample size for phase III
p0	assumed true rate of control group
w	weight for mixture prior distribution
p11	assumed true rate of treatment group
p12	assumed true rate of treatment group
in1	amount of information for p11 in terms of sample size
in2	amount of information for p12 in terms of sample size
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_binary(), EPsProg3_binary() and EPsProg4_binary() is the expected probability of a successful program when performing several phase III trials (2, 3 or 4 respectively)

Examples

EPsProg2_binary(RRgo = 0.8, n2 = 50,  alpha = 0.025, beta = 0.1, 
                                 p0 = 0.6,  w = 0.3, p11 =  0.3, p12 = 0.5, 
                                 in1 = 300, in2 = 600, case = 2, size = "small",
                                 fixed = FALSE)
          EPsProg3_binary(RRgo = 0.8, n2 = 50,  alpha = 0.025, beta = 0.1, 
                                 p0 = 0.6,  w = 0.3, p11 =  0.3, p12 = 0.5, 
                                 in1 = 300, in2 = 600, case = 2, size = "small",
                                 fixed = FALSE)
          EPsProg4_binary(RRgo = 0.8, n2 = 50,  alpha = 0.025, beta = 0.1, 
                                 p0 = 0.6,  w = 0.3, p11 =  0.3, p12 = 0.5, 
                                 in1 = 300, in2 = 600, case = 3, size = "small",
                                 fixed = FALSE)

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