DesignCombo-class: 'DesignCombo'

In crmPack: Object-Oriented Implementation of Dose Escalation Designs

DesignCombo

Description

DesignCombo is the class for two-drug combination dose-escalation designs.

Usage

DesignCombo(
  model,
  nextBest,
  stopping,
  increments,
  cohort_size,
  data,
  startingDose,
  backfill = Backfill(opening = OpeningNone())
)

.DefaultDesignCombo()

Arguments

model	(TwoDrugsCombo) see slot definition.
nextBest	(NextBestNCRM) see slot definition.
stopping	(Stopping) see slot definition.
increments	(Increments) see slot definition.
cohort_size	(CohortSize) see slot definition.
data	(DataCombo) see slot definition.
startingDose	(numeric) see slot definition.
backfill	(Backfill) see slot definition.

Details

This class stores the same core design components as Design, but uses DataCombo and TwoDrugsCombo to represent two-drug combinations.

Slots

model

(TwoDrugsCombo) the model to be used.

nextBest

(NextBestNCRM) the rule to select the next dose combination.

stopping

(Stopping) stopping rule(s) for the trial.

increments

(Increments) how to control increments between dose combinations.

cohort_size

(CohortSize) rules for the cohort sizes.

data

(DataCombo) specifies dose grids and any previously observed data.

startingDose

(numeric) starting dose combination as a numeric vector of length 2.

backfill

(Backfill) rules for backfilling patients in the trial.

Note

Typically, end users will not use the .DefaultDesignCombo() function.

Examples

empty_data <- DataCombo(
  doseGrid = list(
    drug1 = c(10, 20, 30),
    drug2 = c(20, 40, 60)
  )
)

my_model <- TwoDrugsCombo(
  single_models = list(
    drug1 = LogisticLogNormal(
      mean = c(-0.85, 1),
      cov = matrix(c(1, -0.5, -0.5, 1), nrow = 2),
      ref_dose = 10
    ),
    drug2 = LogisticLogNormal(
      mean = c(-0.7, 0.8),
      cov = matrix(c(1.1, -0.3, -0.3, 0.9), nrow = 2),
      ref_dose = 20
    )
  ),
  gamma = 0,
  tau = 1
)

my_next_best <- NextBestNCRM(
  target = c(0.2, 0.35),
  overdose = c(0.35, 1),
  max_overdose_prob = 0.25
)

my_increments <- IncrementsMin(
  increments_list = list(
    IncrementsComboOneDrugOnly(),
    IncrementsComboCartesian(
      drug1 = IncrementsRelative(intervals = c(0), increments = c(1)),
      drug2 = IncrementsRelative(intervals = c(0), increments = c(1))
    )
  )
)

my_stopping <- StoppingMinPatients(nPatients = 20)

design_combo <- DesignCombo(
  model = my_model,
  nextBest = my_next_best,
  stopping = my_stopping,
  increments = my_increments,
  cohort_size = CohortSizeConst(3L),
  data = empty_data,
  startingDose = c(drug1 = 10, drug2 = 20)
)

crmPack documentation built on July 5, 2026, 9:06 a.m.