RE: NONMEM and Bioavailability fraction
Not the same issue, but issues of a similar nature.
Most of the time, it is due to a discrepancy between the model structure and
the dataset.
Among ChatGPT's suggestions below, and I would bet on #1 (relative F between
the two formulations not defined correctly):
1. Bioavailability Fraction Parameter: Ensure that the bioavailability
fraction (F) parameter is correctly defined in the $PK record. A negative value
might indicate an issue with how the parameter is calculated or defined in the
model.
2. Dataset Errors: Verify that your dataset is correctly formatted.
Non-numeric cells, NA values, and unsorted time columns can cause errors in
NONMEM. Ensure that all cells in the dataset are numeric and properly formatted.
3. Additional Parameters: Check the additional parameters in your model,
such as absorption lag time, relative bioavailability fraction, rate parameter
for zero-order input, duration parameter of that input, and scaling parameter.
Incorrect specification or estimation of these parameters can lead to errors.
Cheng
Quoted reply history
From: [email protected] <[email protected]> On Behalf Of
Marie Rajerison
Sent: Tuesday, March 11, 2025 9:50 AM
To: [email protected]; [email protected]
Subject: [EXTERNAL] [NMusers] RE: NONMEM and Bioavailability fraction
Dear NM users
I am running an extravascular pop PK model with dual absorption and got the
following message from NM:
[cid:[email protected]]
Has anyone experienced the same issue and how to fix it?
Thank you in advance for your help
Marie