PMOC DRUGS DEVELOPMENT PROCESS AND PHASE 1 AND 2 Flashcards
including a clinical condition and treated with the test drug
In vivo
drug activity is tested on isolated tissues or cells
In vitro
compound showing a desired pharmacological property which can be used to initiate a medicinal chemistry project
Lead compound
the science of the properties of the drugs and its effects in the body
Pharmacology
the study of the interaction of drugs with cells
Pharmacodynamics
the handling of a drug within the body, it includes the ADME processes
Pharmacokinetics
in vitro and in vivo testing , determination of LD 50
Toxicity testing
the general area of study concerned with the
formulation, manufacturing, stability and effectiveness of a pharmaceutical dosage form
Pharmaceutics
Genotoxicity screening is performed, as well as investigations on drug absorption and metabolism, the toxicity of the drug’s metabolites, and the speed with which the drug and its metabolites are excreted from the body.
Pre clinical studies
Filed before drug may be given to human (clinical trials)
IND
submitted for review and approval after the
completion of the clinical trials and requirements have
been met.
NDA
plays a central role in the elimination of drugs and other foreign compounds (xenobiotics) from the body
Metabolism / Biotransformation
an essential tool for
pharmacists in their role of
selecting and monitoring Pare appropriate drug therapy for nt their patients
Metabolism / Biotransformation
main site of metabolism and detoxification of
endo/exogenous compounds
Liver
– Metabolism before reaching systemic circulation – Limit the BA of orally administered drugs
First-Pass Effect
– Produceamorewater-
soluble compound
– Produce a molecule that can undergo subsequent
phase II reactions
Phase 1
Pathways to attach polar,ionizable
endogenous compounds
- Glucuronidation
- Sulfation
- Glycine conjugation
Pathways to terminateorattenuate biological activity
Methylation
Acetylation
Protectbodyagainst
chemically reactive compounds
GSH conjugation
Funtionalization phase polar functional groups are introduced into the molecule or unmasked by:
Oxidation, Reduction and Hydrolysis
Pathway for direct functionalization group
Aliphatic and Aromatic hydroxylation
modifying or “unmasking” existing functionalities
⚫ reduction of ketones and aldehydes to
alcohols
⚫ oxidation of alcohols to acids
⚫ hydrolysis of ester and amides to yield
COOH, NH2 and OH groups; reduction of azo and nitro compounds to give NH2 moieties; oxidative N-, O- And S- dealkylation to give NH2. OH and SH groups).
Most are mediated by microsomes. and may refer to the change in
oxidation state of the substrate.
Oxidation
What oxidation reaction is oxygen is incorporated into the drug molecule
Hydroxylation
What oxidation reaction causes the loss of part of
the drug molecule
oxidative deamination, dealkylation
form in vitro after cell homogenization and fractionation of ER
Microsomes
primarily associated with protein synthesis
Rough microsomes
contain a class of oxidative enzymes called MFOs
Smooth microsomes
MFO reducing agents
- NADPH (Nicotinamide Adenine
Dinucleotide Phosphate) - Molecular Oxygen
One mole of this enzyme contains one mole each of flavin mononucleotide (FMN) and
flavin adenine dinucleotide • (FAD)
Flavoprotein
Molecular oxygen is also known as
Monooxygenases
Flavoprotient is a electron
transporter
It is cytochrome P450 reductase
NADPH
Name based on light abs at 450nm when complexed with CO
Cytochrome P450
Cytochrome P450 is a electron
Acceptor
Refers to the mixed-function oxidation of aromatic compounds (arenes) to their corresponding phenolic metabolites (arenols)
Aromatic hydroxylation
Epoxide intermediate aromatic hydroxylation
Arene oxide
NIH shift leads to the formation of
arenols
Enzyme use for formation of trans dihydrodiols
Epoxide hydrases
Major route of metabolism for phenyl containing drugs
Aromatic hydroxylation
Hydroxylation occurs at what position
Para
The metabolic oxidation of olefinic carbon—carbon double bonds leads to the corresponding epoxide
Oxirane
The epoxide is cleaved by epoxide hydrases to form
trans diol
more stable than the arene oxides formed from aromatic compounds
Epoxide
Toxicity of olefinic compounds may result from their metabolic conversion to chemically reactive epoxide
– Aflatoxin
– DES
– Stilbene
– Vinylchloride
These are abnormal heme derivative and N-alkylatedprotoporphyrins
Green pigments
Olefinic hydroxylation final metabolite
Transdihydroxylation
Diazepam belongs to
2-ketobenzo
2-ketobenzo common metabolite
Oxazepam
Oxazepam prototype
3 hydroxybenzo
Naturally occurinf carcinogenic agent
Aflatoxin
Other name for alkene
Olefin
Intermediate metabolite formed in drug that undergo N-dealkylation
Carbinolamine
N-hydroxylation intermediate metabolite
N-hydroxylamine
Parent drug of acetaminophen
Phenacitin
Addition of hydrogen or gain electrons
Reductions
play an important role in the metabolism of many compounds containing carbonyl, nitro, and azo group
Reduction
It is recommended in diabetic patients with renal failure, because of the possible accumulation of its active metabolite hydroxyhexamide
Acetohexamide
Azo reduction intermediate metabolite
Hydrazo
reaction of water with substrate resulting in breaking scissile carbon- heteroatom bonds)
Hydrolysis
mediatedbynonspecific
esterases found in the liver, kidney, and intestine and pseudocholinesterases present in plasma
Ester hydrolysis
mediatedbyliver
microsomal amidases. Esterases and deacylases
Amide hydrolysis
This is the active metabolite of acetohexamide.
Hydroxyhexamide
These are susceptible to either a-carbon hydroxylation or N-
oxidation
Amides
endogenous compounds that undergo conjugation reactions
- Bilirubin
- Steroids
- Catecholamines
- Histamine
Glucuronidation enzyme
Glucuronyltransferase
Phase 1 aka
Functionalization
Phase 2 aka
Conjugation
Addition to structure for glucuronidation
Glucuronic acid
Glucuronidation co enzyme
UDPGA
Chlorampenical in neonates can produce
Gray baby syndrome
leadstowater-solubleandinactive metabolite
Sulfation
endogenouscompoundsthatunderogo sulfate conjugation
steroids,heparin,chondroitin, catecholamines, and thyroxine
Sulfation coenzyme
3’-phosphoadenosine- 5’.phosphosulfate (PAPS).
important pathway for detoxifying chemically reactive electrophilic compounds
GSH conjugation
The acetyl group used in N- acetylation of xenobiotics is supplied by
N acetyl coA
Rapid acetylator more likely to develop
isoniazid-associated hepatitis
Rapid acetylator
Eskimos and Asian
Terminate pharmacological activity and detoxification
Acetylation
play an important role in the biosynthesis of many endogenous compounds
Methylation
Methylation 2 compings
epinephrine and melatonin
Metylation cozenzyme
S-adenosylmethionine(SAM)