utility_multiarm: Utility function for multiarm programs with time-to-event...

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

Utility function for multiarm programs with time-to-event outcomes

Description

The utility function calculates the expected utility of our drug development program and is given as gains minus costs and depends on the parameters as on the sample size and expected probability of a successful program. The utility is in further step maximized by the optimal_multiarm() function.

Usage

utility_multiarm(
  n2,
  HRgo,
  alpha,
  beta,
  hr1,
  hr2,
  strategy,
  ec,
  c2,
  c02,
  c3,
  c03,
  K,
  N,
  S,
  steps1,
  stepm1,
  stepl1,
  b1,
  b2,
  b3
)

Arguments

n2	total sample size for phase II; must be divisible by three
HRgo	threshold value for the go/no-go decision rule
alpha	significance level
beta	1-beta power for calculation of sample size for phase III
hr1	assumed true treatment effect on HR scale for treatment 1
hr2	assumed true treatment effect on HR scale for treatment 2
strategy	choose Strategy: 1 ("only best promising"), 2 ("all promising")
ec	control arm event rate for phase II and III
c2	variable per-patient cost for phase II
c02	fixed cost for phase II
c3	variable per-patient cost for phase III
c03	fixed cost for phase III
K	constraint on the costs of the program, default: Inf, e.g. no constraint
N	constraint on the total expected sample size of the program, default: Inf, e.g. no constraint
S	constraint on the expected probability of a successful program, default: -Inf, e.g. no constraint
steps1	lower boundary for effect size category "small" in HR scale, default: 1
stepm1	lower boundary for effect size category "medium" in HR scale = upper boundary for effect size category "small" in RR scale, default: 0.95
stepl1	lower boundary for effect size category "large" in HR scale = upper boundary for effect size category "medium" in RR scale, default: 0.85
b1	expected gain for effect size category "small"
b2	expected gain for effect size category "medium"
b3	expected gain for effect size category "large"

Value

The output of the function utility_multiarm() is the expected utility of the program

Examples

utility_multiarm(n2 = 50, HRgo = 0.8, alpha = 0.05, beta = 0.1,
                            hr1 = 0.7, hr2 = 0.8, strategy = 2, ec = 0.6,
                            c2 = 0.75, c3 = 1, c02 = 100, c03 = 150,
                            K = Inf, N = Inf, S = -Inf,  
                            steps1 = 1, stepm1 = 0.95,  stepl1 = 0.85,
                            b1 = 1000, b2 = 2000, b3 = 3000)

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