R6 class for drug class specifications

Stores the generic drug names (GNNs) and narrative description for a single version of a drug class definition. Each version is a distinct object (e.g., spec_acei_v1, spec_acei_v2).

Active bindings

drug_class: Short drug class identifier (read-only).
version: Version label, e.g. "v1" (read-only).
label: Human-readable drug class label (read-only).

Methods

`DrugSpec$new()`

Create a new DrugSpec.

Usage

DrugSpec$new(
  drug_class,
  label,
  defs = NULL,
  generic_names = character(0L),
  generic_names_probable = character(0L),
  generic_names_cautious = character(0L),
  brand_names = list(),
  generic_defs = NULL,
  version = NULL
)

Arguments

drug_class

Short identifier string, e.g. "acei".

label

Human-readable label.

defs

Character string describing the drug class. May be NULL.

generic_names

Character vector of GNN drug names that are single-indication and aligned with, and FDA-approved for, this drug class's indication. Stored at priority = 1 (core).

generic_names_probable

Character vector of GNN drug names that have more than one indication (e.g., also FDA-approved, or widely used off-label, for a different condition) in addition to this drug class's indication. Stored at priority = 2 (probable).

generic_names_cautious

Character vector of GNN drug names that are included in this drug class despite not having their expected indication approved in the US (e.g., approved for a related but distinct condition, or not marketed in the US at all). Stored at priority = 3 (cautious).

brand_names

Optional named list mapping a GNN drug name (must appear in generic_names, generic_names_probable, or generic_names_cautious) to one or more brand name strings, e.g. list(SEMAGLUTIDE = "Ozempic", "PAROXETINE MESYLATE" = c("Brisdelle", "Pexeva")). Generics with no entry get an empty brand vector. Stored as a list-column (brand) in get_generics() output, since a single generic can map to zero, one, or multiple brands. Ignored (and must be left empty) if generic_defs is supplied.

generic_defs

Optional alternative to generic_names/generic_names_probable/generic_names_cautious/ brand_names, for drug classes whose generics don't all map to a single condition/indication context (e.g. a drug that's core for one condition but cautious for another). A data frame/tibble with required columns generic (character) and priority (integer, 1/2/3), and optional columns condition (character; NA if omitted, meaning "not condition-specific") and brand (character; NA if omitted or unknown). The same generic may appear in multiple rows with different priority/condition combinations (e.g. finerenone at priority 1 for "ckd" and priority 3 for "hypertension"), and multiple brands for one (generic, priority, condition) combination are expressed as duplicate rows differing only in brand:

tibble::tribble(
  ~generic,       ~priority, ~condition,     ~brand,
  "FINERENONE",   1,         "ckd",          "Kerendia",
  "FINERENONE",   3,         "hypertension", "Kerendia",
  "EPLERENONE",   2,         "hypertension", "Inspra"
)

Cannot be combined with generic_names/generic_names_probable/ generic_names_cautious/brand_names.

version

Optional version label string, e.g. "v1".

`DrugSpec$print()`

Print a summary of the spec.

Usage

DrugSpec$print(...)

`DrugSpec$get_generics()`

Retrieve generic (and brand) drug names as a tidy data frame.

Usage

DrugSpec$get_generics(priority = 1L, condition = NULL)

Arguments

priority: Integer vector subsetting confidence tiers to include (1 = core, 2 = probable, 3 = cautious). Default 1.
condition: Optional character vector subsetting to specific condition(s) (only meaningful for specs built with generic_defs; see DrugSpec$new()). NULL (default) applies no condition filtering. When supplied, rows with a condition in condition, and rows with condition = NA (not condition-specific), are both included.

Returns

A tibble with columns generic, brand (a list-column of character vectors — character(0) when a generic has no known brand, length 1+ otherwise), priority, condition (NA unless the spec was built with generic_defs), class, and version. Use tidyr::unnest(result, brand, keep_empty = TRUE) to get one row per brand (this drops the generic entirely for a plain unnest() without keep_empty = TRUE, since most generics have no brand on record).

`DrugSpec$get_defs()`

Retrieve the narrative drug class description.

Usage

DrugSpec$get_defs()

Returns

Character string, or NULL.

`DrugSpec$clone()`

The objects of this class are cloneable with this method.

Usage

DrugSpec$clone(deep = FALSE)

Arguments

deep: Whether to make a deep clone.