PLEASE READ CARE FULLY NEED ANSWER RED MISSING (DUE 15 HRS)
Intravenous
| These equations are for reference only. You do not have to use them to complete your homework. But they help to understand the results! | |||||||||||||||||||||||||
| Plasma concentration (Cp) for one compartment model with iv bolus dosing and first order elimination | |||||||||||||||||||||||||
| Cp= (D/Vd)*exp(-ke*t) | |||||||||||||||||||||||||
| Equation for extension of duration of action | |||||||||||||||||||||||||
| Using the model in this worksheet, please answer the questions in the handout | Ci is the plasma concentration at a given time, assumed to be Ci>Ceff | ||||||||||||||||||||||||
| Please do not change any of the calculations | Delta teff is for how much longer the drug will be active (above Ceff) for a given half-life | ||||||||||||||||||||||||
| You only have to change some of the values of some of the parameters in bold red | This equation can be derived from the Cp(t) equation above | ||||||||||||||||||||||||
| This plot describes the plasma concentration (Cp) of an ideal drug after administration of an intravenous bolus | |||||||||||||||||||||||||
| (There are no drugs with this simple pharmacokinetic behavior, but it is a simple illustrative example) | |||||||||||||||||||||||||
| The drug is considered active in the patient if its plasma concentration is superior to a threshold value "Ceff" determined from previous clinical experience | |||||||||||||||||||||||||
| Parameter | Abbreviation | Units | Your Values | ||||||||||||||||||||||
| Elimination half-life | t1/2 (elim) | h | 4.0 | Same plot, with Y axis set to maximum Cp 10 ug/ml | |||||||||||||||||||||
| Dose | D | mg/person | |||||||||||||||||||||||
| Active plasma concentration threshold | Ceff | ug/ml | 1.0 | ||||||||||||||||||||||
| Don't touch these cells | |||||||||||||||||||||||||
| Elimination rate | ke | 1/h | 0.173 | ||||||||||||||||||||||
| Apparent volume of distribution | Vd | L/person | 14 | ||||||||||||||||||||||
| Threshold plot | Time (h) | Ceff (ug/ml) | |||||||||||||||||||||||
| 0 | 1.0 | ||||||||||||||||||||||||
| 25 | 1.0 | ||||||||||||||||||||||||
| Don't touch these cells | |||||||||||||||||||||||||
| Plot | |||||||||||||||||||||||||
| Time (h) | Cp (ug/ml) | ||||||||||||||||||||||||
| 0 | 0.0 | ||||||||||||||||||||||||
| 0.1 | 0.0 | ||||||||||||||||||||||||
| 0.25 | 0.0 | ||||||||||||||||||||||||
| 0.5 | 0.0 | ||||||||||||||||||||||||
| 1 | 0.0 | ||||||||||||||||||||||||
| 1.5 | 0.0 | ||||||||||||||||||||||||
| 2 | 0.0 | ||||||||||||||||||||||||
| 3 | 0.0 | ||||||||||||||||||||||||
| 4 | 0.0 | ||||||||||||||||||||||||
| 5 | 0.0 | ||||||||||||||||||||||||
| 6 | 0.0 | ||||||||||||||||||||||||
| 8 | 0.0 | ||||||||||||||||||||||||
| 10 | 0.0 | ||||||||||||||||||||||||
| 12 | 0.0 | ||||||||||||||||||||||||
| 14 | 0.0 | ||||||||||||||||||||||||
| 16 | 0.0 | ||||||||||||||||||||||||
| 18 | 0.0 | ||||||||||||||||||||||||
| 20 | 0.0 | ||||||||||||||||||||||||
| 22 | 0.0 | ||||||||||||||||||||||||
| 24 | 0.000 | ||||||||||||||||||||||||
| 26 | 0.0 | ||||||||||||||||||||||||
| 28 | 0.0 | ||||||||||||||||||||||||
| 30 | 0.0 | ||||||||||||||||||||||||
PK Intravenous Administration
Cp (ug/ml) 0 0.1 0.25 0.5 1 1.5 2 3 4 5 6 8 10 12 14 16 18 20 22 24 26 28 30 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Ceff (ug/ml) 0 25 1 1
Time (h)
Cp (ug/ml)
PK Intravenous Administration
Cp (ug/ml) 0 0.1 0.25 0.5 1 1.5 2 3 4 5 6 8 10 12 14 16 18 20 22 24 26 28 30 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Ceff (ug/ml) 0 25 1 1
Time (h)
Cp (ug/ml)
Subcutaneous
| CLRE-238 | Applied Translational Research | These equations are for reference only. You do not have to use them to complete your homework. But they help to understand the results! | ||||||||||||||||||
| Spring 2021 | ||||||||||||||||||||
| PK-PD Primer Homework | Plasma concentration (Cp) for one compartment model with sc bolus dosing and first order elimination | |||||||||||||||||||
| Date | 3/30/21 | |||||||||||||||||||
| Claudio D. Schteingart Ph.D. | ||||||||||||||||||||
| C(t) is Cp the plasma concentration as a function of time | ||||||||||||||||||||
| f is the bioavailability (scale 0 to 1) of the drug in the sc space | ||||||||||||||||||||
| Using the model in this worksheet, please answer the questions in the handout | ka is the absorption rate, ke is the elimination rate | |||||||||||||||||||
| Please do not change any of the calculations | D is the dose, Vd is the apparent volume of distribution | |||||||||||||||||||
| You only have to change some of the values of some of the parameters in bold red | ||||||||||||||||||||
| Equation for extension of duration of action | ||||||||||||||||||||
| Ci is the plasma concentration at a given time, assumed to be Ci>Ceff | ||||||||||||||||||||
| Delta teff is for how much longer the drug will be active (above Ceff) for a given half-life | ||||||||||||||||||||
| This equation can be used during the elimination phase of the above curve | ||||||||||||||||||||
| This plot describes the plasma concentration (Cp) of an ideal drug after administration of a subcutaneous bolus | ||||||||||||||||||||
| The drug is considered active in the patient if its plasma concentration is superior to a threshold value "Ceff" determined from previous clinical experience | ||||||||||||||||||||
| If the absorption half-life equals the elimination half-life the math fails (division by zero). If needed, enter a slightly different value, e.g. 3.99 or 4.01 instead of 4.00 | ||||||||||||||||||||
| Same plot, with Y axis set to maximum Cp 10 ug/ml | ||||||||||||||||||||
| Parameter | Abbreviation | Units | Your Values | |||||||||||||||||
| Absorption half-life | t1/2 (abs) | h | 24.00 | |||||||||||||||||
| Elimination half-life | t1/2 (elim) | h | 5.0 | |||||||||||||||||
| Dose | D | mg/person | 9.43 | |||||||||||||||||
| Active plasma concentration threshold | Ceff | ug/ml | 5.0 | |||||||||||||||||
| Don't touch these cells | ||||||||||||||||||||
| Subcutaneous bioavailability 0 to 1 | f | 1 | ||||||||||||||||||
| Apparent volume of distribution | Vd | L/person | 14 | |||||||||||||||||
| Absorption rate | ka | 1/h | 0.029 | |||||||||||||||||
| Elimination rate | ke | 1/h | 0.139 | |||||||||||||||||
| Multiplication factor | fDka/(Vd(Ka-ke)) | ug/ml | -0 | |||||||||||||||||
| Threshold plot | Time (h) | Ceff (ug/ml) | ||||||||||||||||||
| 0 | 5.0 | |||||||||||||||||||
| 26 | 5.0 | |||||||||||||||||||
| Don't touch these cells | ||||||||||||||||||||
| Plot | ||||||||||||||||||||
| Time (h) | Cp (ug/ml) | |||||||||||||||||||
| 0 | 0.00 | |||||||||||||||||||
| 0.1 | 0.00 | |||||||||||||||||||
| 0.25 | 0.00 | |||||||||||||||||||
| 0.5 | 0.01 | |||||||||||||||||||
| 1 | 0.02 | |||||||||||||||||||
| 1.5 | 0.03 | |||||||||||||||||||
| 2 | 0.03 | |||||||||||||||||||
| 2.5 | 0.04 | |||||||||||||||||||
| 3 | 0.05 | |||||||||||||||||||
| 3.5 | 0.05 | |||||||||||||||||||
| 4 | 0.06 | |||||||||||||||||||
| 5 | 0.06 | |||||||||||||||||||
| 6 | 0.07 | |||||||||||||||||||
| 7 | 0.08 | |||||||||||||||||||
| 9 | 0.09 | |||||||||||||||||||
| 11 | 0.09 | |||||||||||||||||||
| 13 | 0.09 | |||||||||||||||||||
| 15 | 0.09 | |||||||||||||||||||
| 17 | 0.09 | |||||||||||||||||||
| 19 | 0.09 | |||||||||||||||||||
| 21 | 0.09 | |||||||||||||||||||
| 23 | 0.08 | |||||||||||||||||||
| 24 | 0.08 | |||||||||||||||||||
| 25 | 0.08 | |||||||||||||||||||
| 26 | 0.08 | |||||||||||||||||||
| 27 | 0.08 |
PK Subcutaneous Administration
Cp (ug/ml) 0 0.1 0.25 0.5 1 1.5 2 2.5 3 3.5 4 5 6 7 9 11 13 15 17 19 21 23 24 25 26 27 0 1.9291349543759174E-3 4.7627511742739078E-3 9.3290009959562988E-3 1.7899518669098738E-2 2.5764263897523468E-2 3.297239017841809E-2 3.9569732249353361E-2 4.5599028724170154E-2 5.1100129814037637E-2 5.6110191132563512E-2 6.4793416734735515E-2 7.1898633268821469E-2 7.764303677600605E-2 8.5779467479190435E-2 9.0433868498689868E-2 9.2534238683107894E-2 9.2779107146231402E-2 9.1693364761172624E-2 8.967056151835319E-2 8.7004947768308957E-2 8.3915743577409357E-2 8.2264905141199454E-2 8.056551884472278E-2 7.8831334871670267E-2 7.7074110918482291E-2 Ceff (ug/ml) 0 26 5 5
Time (h)
Cp (ug/ml)
PK Subcutaneous Administration
Cp (ug/ml) 0 0.1 0.25 0.5 1 1.5 2 2.5 3 3.5 4 5 6 7 9 11 13 15 17 19 21 23 24 25 26 27 0 1.9291349543759174E-3 4.7627511742739078E-3 9.3290009959562988E-3 1.7899518669098738E-2 2.5764263897523468E-2 3.297239017841809E-2 3.9569732249353361E-2 4.5599028724170154E-2 5.1100129814037637E-2 5.6110191132563512E-2 6.4793416734735515E-2 7.1898633268821469E-2 7.764303677600605E-2 8.5779467479190435E-2 9.0433868498689868E-2 9.2534238683107894E-2 9.2779107146231402E-2 9.1693364761172624E-2 8.967056151835319E-2 8.7004947768308957E-2 8.3915743577409357E-2 8.2264905141199454E-2 8.056551884472278E-2 7.8831334871670267E-2 7.7074110918482291E-2 Ceff (ug/ml) 0 26 5 5
Time (h)
Cp (ug/ml)