Description
Supplied exposure normalization for a research comparison.
Pharmacokinetic research describes concentration over time using measurement units and an explicit model. Concentration-time area, its time-weighted moment, inverse-time rate constants, clearance, and volume are related but distinct quantities. A conversion or local model term does not estimate every parameter or validate a complete study.
Supplied exposure normalization for a research comparison.
When to use this tool
Use PK Bioavailability Dose Normalized Ratio when you need this concentration-time conversion, sampling check, local integral panel, or explicitly supplied kinetic-model term.
How to use the tool and how it works
- Enter testAuc, referenceAuc, testAmount, referenceAmount. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read testNormalized, referenceNormalized, relativeFraction. Use the output convention below.
For nonnegative testAuc and positive referenceAuc, testAmount, and referenceAmount return testNormalized=testAuc/testAmount, referenceNormalized=referenceAuc/referenceAmount, and relativeFraction=testAuc*referenceAmount/(referenceAuc*testAmount).1
AUC summarizes systemic exposure, while comparing bioavailability requires a suitable study and reference product. A single dose-normalized area ratio does not itself establish clinical equivalence.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| testAuc | Test Auc | Required. Finite number; minimum 0. |
| referenceAuc | Reference Auc | Required. Finite number; strictly above 0. |
| testAmount | Test Amount | Required. Finite number; strictly above 0. |
| referenceAmount | Reference Amount | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| testNormalized | Test Normalized | Required. Finite number. |
| referenceNormalized | Reference Normalized | Required. Finite number. |
| relativeFraction | Relative Fraction | Required. Finite number. |
{
"input": {
"testAuc": 40,
"referenceAuc": 50,
"testAmount": 100,
"referenceAmount": 100
},
"output": {
"testNormalized": 0.4,
"referenceNormalized": 0.5,
"relativeFraction": 0.8
}
}Limitations and assumptions
- AUCs and amounts need compatible units and comparable study conditions. RelativeFraction may exceed one and is not automatically absolute bioavailability or a bioequivalence conclusion.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Signed zero is exported as zero.
Alternative or Complementary methods
Use a complete study analysis when a local panel, transformation, or model factor is insufficient. Check sampling times, censoring, assay support, unit conventions, and the validity of the assumed kinetic regime.
References
-
Calculation and input contract: pharmacokinetics/pk-bioavailability-dose-normalized-ratio — tool.io
-
Bioavailability Studies Submitted in NDAs or INDs — General Considerations (April 2022) — U.S. Food and Drug Administration
Similar or alternative tools
- PK Clearance Research AUC Unit Factor
Research amount/AUC arithmetic with supplied unit bases and bioavailability.
- PK Noncompartmental Extrapolated Tail Share
For positive observedAuc and terminalRate and nonnegative lastConcentration return tailArea=lastConcentration/terminalRate, totalArea=observedAuc+tailArea, and extrapolatedFraction=lastConcentration/(terminalRate*observedAuc+lastConcentration).