Late Stage Drug Development

Question 1

what do you use to test for intestinal absorption>

Answer 1

a Caco-2 cell monolayer

Question 2

if a drug has stability against CYP450, less than ____ metabolism to the drug will occur after 1 hour

Answer 2

50%

Question 3

for in vivo metabolic stability studies, greater than _______ percent of the drug should remain after 1 hour in rodents

Answer 3

20

Question 4

general cytotoxicity studies include

Answer 4

ATP measurement, MTS, enzyme release

Question 5

to check for mitochondrial dysfunction:

Answer 5

look at oxygen consumption

Question 6

hERG potassium channel inhibition can cause

Answer 6

life-threatening arrhythmias

Question 7

drug-drug interactions are usually _________ related

Answer 7

metabolism

Question 8

paracellular and transcellular are forms of ____ uptake

Answer 8

passive

Question 9

carrier mediated uptake is a form of ____ uptakes

Answer 9

active

Question 10

Efflux is mediated by __________

Answer 10

p-glycoprotein

Question 11

Caco-2 cells exhibit __________ mechanisms

Answer 11

all forms of uptake and efflux

Question 12

the small intestine side of a membrane is called the _______ side

Answer 12

apical

Question 13

the blood side of a membrane is called the __ side

Answer 13

basolateral

Question 14

how many layer of cells are used in Caco-2 testing

Answer 14

one, a monolayer

Question 15

hepatocytes are isolated from ____ and used as _______ cells. They contain the entire range of metabolic enzymes. A downside is that they are ____

Answer 15

animal/ intact/ harder to grow and use

Question 16

microsomes:

Answer 16

subcellular fraction of digested liver

Question 17

microsomes consist of ________

Answer 17

endoplasmic reticulum

Question 18

microsomes contain ____ enzymes only

Answer 18

phase I

Question 19

____ and ______ are phase I enzymes

Answer 19

CYP450/ FMO

Question 20

microsomes are _____ to use than hepatocytes

Answer 20

easier

Question 21

metabolism stability: half life should definitely be over _______, and _____ would probably be good to proceed to the next step

Answer 21

10 minutes/ 20 minutes

Question 22

To do stability tests: start with a 96 well plate. Add ________. Then add ________. Now _________. Then ________ and ______ –> quantification of parent compound disappearance

Answer 22

chemicals/ hepatocytes or microsomes/ incubate/ extract/ analyze

Question 23

to see if a drug inhibits CYP450, add ___, then ____ and incubate. Then add ____, incubate, and check for ______.

Answer 23

chemicals/ hepatocytes/ P450 substrate/ metabolites

Question 24

toxicity can be measured as hepatocyte viability in the presence of the drug using _____

Answer 24

MTS/ MTT colorimetric assay

Question 25

name three cytoplasmic enzymes that can be tested for to analyze the amount of cell death

Answer 25

lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase

Question 26

_____ percent of the cell's energy is produced in the mitochondria

Answer 26

90

Question 27

where is the programmed cell death control center located?

Answer 27

in the mitochondria

Question 28

what are three main screens for mitochondrial toxicity?

Answer 28

disrupted energy metabolism, increased free radical generation, altered apoptosis

Question 29

name four screening assays to check for energy metabolism disruption

Answer 29

ATP production (reduction = toxicity), membrane potential, oxygen utilization, mt biogenesis

Question 30

name a screening assay that checks for free radical production

Answer 30

ROS production

Question 31

name a screening assay that checks apoptosis induction

Answer 31

PARP activation

Question 32

name three mechanistic assays that check energy metabolism disruption

Answer 32

OXPHOS Enzyme activity, phospo + acetyl, metabolic protein expression panel

Question 33

name three mechanistic assays used to check for free radical production

Answer 33

protein nitration panel, protein oxidation panel, antioxidant protein expression panel

Question 34

name two mechanistic assays use to check for apoptosis induction

Answer 34

cell fractionation and protein translocation panel, apoptosis protein expression panel

Question 35

normal heart rhythms are governed by

Answer 35

electrical pulses (based on ion transport)

Question 36

disruption of the electrical pulses that regulate heart rhythms results in

Answer 36

prolonged QT interval (prolonged heart beat) eventually arrythmias and possibly death

Question 37

the hERG potassium channel is the major protein responsible for conducting K+ ions ____ the heart muscle cells

Answer 37

out of

Question 38

name two drugs that are hERG inhibitors

Answer 38

fluroquinolones, terfenadine

Question 39

what test can you use to check for genotoxicity?

Answer 39

Ames test

Question 40

You need ___________, _____________, ________ and ____ studies to open an IND

Answer 40

proof of principle in most appropriate animal model, acute and chronic toxicity studies, safety pharmacology (respiratory, CVS, CNS), ADME panels

Question 41

acute toxicity studies:

Answer 41

one large dose or several large does given over less than two weeks

Question 42

chronic toxicity studies:

Answer 42

should be for the length of the clinical trial

Question 43

therapeutic index:

Answer 43

LD50/ED50

Question 44

phase I trials provide ___________ and determine _______

Answer 44

initial pharmacologic and pharmacokinetic data/ maximum tolerable dosage (MTD)

Question 45

initial dose is usually _____ for phase I trials

Answer 45

1/10 of MELD10

Question 46

______ ______ volunteers are used in a phase I trial

Answer 46

20-100/ healthy

Question 47

________ interactions studies are performed in phase I trials

Answer 47

drug-food

Question 48

how long are drug patents for?

Answer 48

20 years

Question 49

four main criteria for patentability:

Answer 49

novelty, inventive step, enablement, support (justification for claims of efficacy)

Question 50

patent claims are written to cover ____

Answer 50

a wide range of compounds in a given class (scaffold)

Question 51

terfenadine is a prodrug _____ converted to ______-- by ________. It is a _______.

Answer 51

antihistamine/ fexofenadine (Allegra)/ CYP 450 3A4/ hERG channel inhibitor

Question 52

name four hERG channel inhibitors

Answer 52

HIV protease inhibitors, Gleevec (cancer drug), ketoconazonle, grapefruit juice

Question 53

name two types of hERG channel inducers

Answer 53

barbiturates, HIV reverse transcriptase inhibitors