DDI-antacid

Prediction System for DDI AUC Ratio of Weakly Basic Drugs Combined with ARA Under Fasting State (Integrated with ADMETlab3.0 Interface)

Log P*

Example

1.pKA(base)*

SolFactor*

2.pKA(base)

SolFactor

3.pKA(acid)

SolFactor

Solubility (pH=6.8)*

(mg/mL)

Particle radius*

(um)

Peff (Source:Human)*

(cm/sx10*4)

Solubilization Ratio*

Mean Precipitation Time*

(sec)

CL*

(L/h/kg)

Vc*

(L/kg)

K12*

(1/h)

K21*

(1/h)

K13*

(1/h)

K31*

(1/h)

Dosage Form*

Dose*

(mg)

Altered pH*

Predicted DDl AUC Ratio

Notes:

1.Items marked with * are mandatory, which can be obtained from experimental data or predicted values derived from professional software such as ADMETlab3.0 based on the drug’s molecular structure.

2. SolFactor can be simply estimated using the formula: SolFactor = 20/intrinsic solubility. If the drug’s solubility at two different pH values is available (one at least two pH units above and one at least two pH units below the pKa), SolFactor can be determined by dividing the higher solubility by the lower one.

3. If the drug’s pharmacokinetic data is fitted to a one-compartment model, K12, K21, K13, and K31 are set to 0; for a two-compartment model, K13 and K31 are set to 0.

4. In "Dosage Form": Option 1 = immediate-release tablets; Option 2 = immediate-release capsules.

5. "Altered pH" refers to the gastric pH after ARA administration, with a range of 3.3–8.0.

6. It is recommended that when the ARA regimen is esomeprazole 40 mg once daily, the elevated "Altered pH" can be set to 4.78; for omeprazole 40 mg once daily, it can be set to 4.5; for omeprazole 20 mg once daily, it can be set to 4.2; for rabeprazole 20 mg once daily, it can be set to 4.6; and for rabeprazole 40 mg once daily, it can be set to 5.0.

7. DDl AUC Ratio=（AUC in the presence of ARA）/（AUC in the absence of ARA）