gen2simon: Generalized Simon's 2-stage phase II design

Description

Calculates generalized optimal and minimax 2-stage phase II designs based on the R function ph2simon.

Usage

gen2simon(pu, pa, ep1, ep2, nmax=100)
# S3 method for gen2simon
print(x, …)
# S3 method for gen2simon
plot(x, …)

Arguments

unacceptable response/toxicity rate

response/toxicity rate that is desirable

ep1

threshold for the probability of declaring drug/treatment desirable under p0

ep2

threshold for the probability of rejecting the drug/treatment under p1

nmax

maximum total sample size (default 100; can be at most 500)

object returned by gen2simon

...

arguments to be passed onto plot and print commands called within

Value

gen2simon returns a list with pu, pa, alpha, beta and nmax as above and:

out

matrix of best 2 stage designs for each value of total sample size n. The 6 columns are: r1, n1, r, n, EN(p0), PET(p0), alpha, beta

The "print" method formats and returns the minimax and optimal designs. The "plot" plots the expected sample size agains the maximum sample size as in Jung et al., 2001

References

Kim S and Wong WK. Phase II Two-Stage Single-Arm Clinical Trials for Testing Toxicity Levels. Commun Stat Appl Methods. 2019 Mar;26(2):163-173. https://www.ncbi.nlm.nih.gov/pubmed/31106162.

Jung SH, Carey M and Kim KM. (2001). Graphical Search for Two-Stage Designs for Phase II Clinical Trials. Controlled Clinical Trials 22, 367-372.

Simon R. (1989). Optimal Two-Stage Designs for Phase II Clinical Trials. Controlled Clinical Trials 10, 1-10.

Examples

Run this code

# NOT RUN {
  # Two-stage safety design with pu (p0) = 0.33 vs. pa (p1) = 0.20
  gen2simon(0.33, 0.20, 0.05, 0.20)
  gen2simon(0.33, 0.20, 0.05, 0.10, nmax=150)

  # Two-stage efficacy design with pu (p0) = 0.67 vs. pa (p1) = 0.80
  gen2simon(0.67, 0.80, 0.05, 0.20)
  gen2simon(0.67, 0.80, 0.05, 0.10, nmax=150)

  # save, print and plot
  safety2 = gen2simon(0.33, 0.20, 0.05, 0.20)
  print(safety2)
  plot(safety2)
# }