Semaglutide Titration (20 weeks)

Semaglutide: drug concentration in plasma (nmol/L).

Fixed reference profile: Published reference: 85 kg white, non-Hispanic female under 65 with type 2 diabetes and normal renal function. Subcutaneous semaglutide solution in the SUSTAIN phase III program; Subcutaneous. Fixed reference weight: 85 kg.

Changing dose or schedule explores a scenario; it does not personalize the reference profile or establish a studied regimen.

Input dose basis: Milligrams of semaglutide, not solution volume, syringe units or a salt/product conversion.

Source exposure scope: Published phase III maintenance groups were 0.5 and 1 mg weekly. Other amounts or timings are mathematical extrapolations of this fixed reference.

Published one-compartment reference: 85 kg adult with type 2 diabetes

semaglutide-petri-2018-fixed-reference · version 1

• Abdominal administration; all reference covariate factors and individual random effects fixed at their reference values.
• The source 1 mg maintenance-group clearance is held fixed when the entered amount changes; dose-group and other covariate effects are not implemented.
• Apparent clearance and volume already incorporate bioavailability; no additional availability factor is applied.
• Zero pre-existing semaglutide before the entered dose history; first-order absorption and linear elimination.

Model structure

One compartment with absorption

Apparent clearance (CL/F)

0.0478 L/hour

Apparent central volume (Vc/F)

12.2 L

Absorption rate (ka)

0.0286 /hour

Input mass conversion

1 mg modelled mass per mg entered

• This is a fixed reference calculation, not an individual blood-level prediction or the full published covariate model.
• The source used sparse steady-state samples and fixed absorption. Initial-dose peak timing is a model extrapolation, not a verified patient-specific endpoint.
• Oral semaglutide, compounded preparations and formulation changes are outside this model; approval of a product does not validate a different formulation.
• Concentration does not predict weight loss, glucose response, tolerability or a safe dose. A clearance threshold is not a safety or testing guarantee.

• Petri et al. 2018 — semaglutide population pharmacokinetics

  Methods: fixed ka 0.0286/h and reference covariates. Results / Table S3: reference CL/F 0.0478 L/h and V/F 12.2 L. Apparent parameters are used directly.

• Overgaard et al. 2019 — clinical pharmacokinetics of semaglutide

  Table 5 independently lists the previous phase III one-compartment parameters. The separate two-compartment parameters are not mixed into this reference.

• Novo Nordisk Ozempic prescribing information

  Section 11 supplies molecular weight for mass-to-molar conversion. Label population exposure is a secondary comparison, not a fitted single-dose peak.