GOODMAN AND GILMAN'S THE
PHARMACOLOGICAL BASIS OF
THERAPEUTICS
14TH EDITION
• AUTHOR(S)LAURENCE BRUNTON;
BJORN KNOLLMANN
TEST BANK
1⃣
Reference
Ch. 1 — Lead Identification & Natural Products → Translational
Hit Validation
Stem
A natural product isolated from a rainforest plant shows potent
inhibition of a kinase implicated in chemotherapy-resistant
leukemia in vitro. An elderly patient (78 y) with reduced hepatic
function is enrolled in a first-in-human study of an optimized
,derivative. Which preclinical feature most strongly predicts the
derivative will fail due to idiosyncratic hepatotoxicity in
humans?
Options
A. Demonstrates high potency (IC₅₀ < 10 nM) against the target
kinase in cell lines.
B. Undergoes bioactivation to a reactive metabolite in human
liver microsomes but not in rodent microsomes.
C. Shows low plasma protein binding (fraction unbound > 0.5) in
animal models.
D. Causes reversible elevations in ALT in high-dose rodent
toxicity studies that resolve during washout.
Correct Answer
B
Rationale — Correct (B)
Bioactivation to reactive metabolites in human liver
microsomes indicates a species-specific metabolic pathway
producing electrophiles capable of covalent protein binding and
immune responses that underlie idiosyncratic hepatotoxicity. If
rodents lack this pathway, animal safety studies may miss
human risk. This metabolic finding strongly predicts human
hepatotoxicity risk—especially in older patients with reduced
hepatic reserve.
Rationale — Incorrect
A. High in vitro potency alone does not predict idiosyncratic
hepatotoxicity; it informs dose but not specific toxic metabolic
,pathways.
C. Low plasma protein binding increases free drug exposure but
is not specific for idiosyncratic liver injury mechanisms.
D. Reversible ALT rises in rodents that resolve suggest dose-
related, non-idiosyncratic toxicity that may be manageable;
species differences can still limit relevance.
Teaching Point
Human-specific reactive metabolite formation predicts
idiosyncratic hepatotoxicity risk.
Citation
Brunton, L. L., & Knollmann, B. C. (2023). Goodman & Gilman’s
The Pharmacological Basis of Therapeutics (14th ed.). Ch. 1.
2️⃣
Reference
Ch. 1 — High-Throughput Screening (HTS) → Hit Triage & False
Positives
Stem
A biotech company screens 200,000 compounds using an HTS
fluorescence assay for an ion channel activator. Several hits
show strong signal but later fail in orthogonal electrophysiology
assays. Which characteristic of the initial hits most likely
explains the false-positive HTS signal?
Options
A. Compounds are highly lipophilic (cLogP > 6), causing
, membrane accumulation.
B. Compounds are known to be fluorescent at the assay
wavelength.
C. Compounds demonstrate low micromolar potency in a cell
viability assay.
D. Compounds have high aqueous solubility, improving assay
exposure.
Correct Answer
B
Rationale — Correct (B)
Autofluorescent compounds produce artifactual signals in
fluorescence-based HTS readouts independent of actual
biological activity, yielding false positives that fail in orthogonal
(non-fluorescent) assays such as electrophysiology. Identifying
and triaging fluorescent artifacts is essential during hit
validation.
Rationale — Incorrect
A. High lipophilicity can cause nonspecific effects but wouldn’t
specifically create a fluorescence signal.
C. Activity in cell viability assays suggests cytotoxicity, not assay
fluorescence artifact.
D. High aqueous solubility generally reduces assay artifacts
rather than causing false fluorescence.
Teaching Point
Use orthogonal assays to eliminate fluorescent and other
reporter artifacts from HTS hits.
PHARMACOLOGICAL BASIS OF
THERAPEUTICS
14TH EDITION
• AUTHOR(S)LAURENCE BRUNTON;
BJORN KNOLLMANN
TEST BANK
1⃣
Reference
Ch. 1 — Lead Identification & Natural Products → Translational
Hit Validation
Stem
A natural product isolated from a rainforest plant shows potent
inhibition of a kinase implicated in chemotherapy-resistant
leukemia in vitro. An elderly patient (78 y) with reduced hepatic
function is enrolled in a first-in-human study of an optimized
,derivative. Which preclinical feature most strongly predicts the
derivative will fail due to idiosyncratic hepatotoxicity in
humans?
Options
A. Demonstrates high potency (IC₅₀ < 10 nM) against the target
kinase in cell lines.
B. Undergoes bioactivation to a reactive metabolite in human
liver microsomes but not in rodent microsomes.
C. Shows low plasma protein binding (fraction unbound > 0.5) in
animal models.
D. Causes reversible elevations in ALT in high-dose rodent
toxicity studies that resolve during washout.
Correct Answer
B
Rationale — Correct (B)
Bioactivation to reactive metabolites in human liver
microsomes indicates a species-specific metabolic pathway
producing electrophiles capable of covalent protein binding and
immune responses that underlie idiosyncratic hepatotoxicity. If
rodents lack this pathway, animal safety studies may miss
human risk. This metabolic finding strongly predicts human
hepatotoxicity risk—especially in older patients with reduced
hepatic reserve.
Rationale — Incorrect
A. High in vitro potency alone does not predict idiosyncratic
hepatotoxicity; it informs dose but not specific toxic metabolic
,pathways.
C. Low plasma protein binding increases free drug exposure but
is not specific for idiosyncratic liver injury mechanisms.
D. Reversible ALT rises in rodents that resolve suggest dose-
related, non-idiosyncratic toxicity that may be manageable;
species differences can still limit relevance.
Teaching Point
Human-specific reactive metabolite formation predicts
idiosyncratic hepatotoxicity risk.
Citation
Brunton, L. L., & Knollmann, B. C. (2023). Goodman & Gilman’s
The Pharmacological Basis of Therapeutics (14th ed.). Ch. 1.
2️⃣
Reference
Ch. 1 — High-Throughput Screening (HTS) → Hit Triage & False
Positives
Stem
A biotech company screens 200,000 compounds using an HTS
fluorescence assay for an ion channel activator. Several hits
show strong signal but later fail in orthogonal electrophysiology
assays. Which characteristic of the initial hits most likely
explains the false-positive HTS signal?
Options
A. Compounds are highly lipophilic (cLogP > 6), causing
, membrane accumulation.
B. Compounds are known to be fluorescent at the assay
wavelength.
C. Compounds demonstrate low micromolar potency in a cell
viability assay.
D. Compounds have high aqueous solubility, improving assay
exposure.
Correct Answer
B
Rationale — Correct (B)
Autofluorescent compounds produce artifactual signals in
fluorescence-based HTS readouts independent of actual
biological activity, yielding false positives that fail in orthogonal
(non-fluorescent) assays such as electrophysiology. Identifying
and triaging fluorescent artifacts is essential during hit
validation.
Rationale — Incorrect
A. High lipophilicity can cause nonspecific effects but wouldn’t
specifically create a fluorescence signal.
C. Activity in cell viability assays suggests cytotoxicity, not assay
fluorescence artifact.
D. High aqueous solubility generally reduces assay artifacts
rather than causing false fluorescence.
Teaching Point
Use orthogonal assays to eliminate fluorescent and other
reporter artifacts from HTS hits.
