Stages of drug discovery process MCQs With Answer

Introduction: The stages of drug discovery outline the systematic drug discovery process from target identification to clinical trials and regulatory approval. For B.Pharm students, understanding target identification, target validation, hit identification, hit-to-lead, lead optimization, ADMET assessment, preclinical studies and clinical trials is essential. Emphasis on structure-based design, high-throughput screening, SAR, pharmacokinetics, toxicology and regulatory submissions prepares students for practical pharmaceutical research and development. Mastery of these concepts improves drug candidate selection, risk assessment and decision-making in discovery pipelines. This focused, keyword-rich overview supports exam preparation and applied learning in pharmaceutical sciences. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. Which stage of the drug discovery process focuses on finding a biological molecule whose modulation affects disease?

• Target identification
• Lead optimization
• Clinical trials
• Scale-up manufacturing

Correct Answer: Target identification

Q2. What is the primary aim of target validation?

• Confirm the target’s role in disease biology and druggability
• Determine manufacturing cost of the drug
• Finalize marketing strategy
• Perform human safety testing

Correct Answer: Confirm the target’s role in disease biology and druggability

Q3. Which method is commonly used in hit identification to rapidly test many compounds?

• High-throughput screening (HTS) of compound libraries
• Phase I clinical trial
• Good Manufacturing Practice (GMP) audit
• Post-marketing surveillance

Correct Answer: High-throughput screening (HTS) of compound libraries

Q4. Structure-based drug design primarily requires which information?

• The three-dimensional structure of the biological target
• Human volunteer blood samples
• Large-scale production facilities
• Marketing authorization data

Correct Answer: The three-dimensional structure of the biological target

Q5. What is the main goal of lead optimization?

• Improve potency, selectivity and ADMET properties of lead compounds
• Conduct phase III trials
• File the New Drug Application (NDA)
• Perform stability testing only

Correct Answer: Improve potency, selectivity and ADMET properties of lead compounds

Q6. ADMET in drug discovery stands for which set of properties?

• Absorption, Distribution, Metabolism, Excretion, Toxicity
• Activity, Drug-likeness, Molecular weight, Efficacy, Toxicology
• Analytical, Design, Manufacturing, Evaluation, Testing
• Adsorption, Diffusion, Metabolism, Elimination, Titration

Correct Answer: Absorption, Distribution, Metabolism, Excretion, Toxicity

Q7. Preclinical studies are primarily performed to:

• Evaluate safety, efficacy and toxicity in animal models before clinical trials
• Obtain marketing approval from regulators
• Assess pharmacovigilance signals after launch
• Design patient recruitment strategies

Correct Answer: Evaluate safety, efficacy and toxicity in animal models before clinical trials

Q8. An Investigational New Drug (IND) application must be submitted prior to which step?

• Initiate human clinical trials (Phase I)
• Begin lead optimization
• Submit marketing authorization (NDA)
• Start post-marketing surveillance

Correct Answer: Initiate human clinical trials (Phase I)

Q9. The primary objective of Phase I clinical trials is to:

• Assess safety, tolerability and pharmacokinetics in healthy volunteers
• Confirm large-scale efficacy in patients
• Obtain pricing approval
• Evaluate long-term post-marketing safety

Correct Answer: Assess safety, tolerability and pharmacokinetics in healthy volunteers

Q10. Phase II clinical trials are mainly designed to:

• Evaluate efficacy and dose-ranging in patients with the disease
• Test formulation stability under stress
• Scale up commercial manufacturing
• Conduct animal toxicology studies

Correct Answer: Evaluate efficacy and dose-ranging in patients with the disease

Q11. What is the main purpose of Phase III clinical trials?

• Confirm efficacy and monitor adverse reactions in large patient populations
• Perform initial target identification
• Screen compound libraries by HTS
• Develop analytical method validation only

Correct Answer: Confirm efficacy and monitor adverse reactions in large patient populations

Q12. Structure–activity relationship (SAR) studies are typically performed using:

• Systematic chemical modification and medicinal chemistry approaches
• Only clinical endpoints in Phase III
• Market research surveys
• GMP manufacturing audits

Correct Answer: Systematic chemical modification and medicinal chemistry approaches

Q13. High-throughput screening (HTS) is intended to:

• Rapidly test thousands of compounds for activity against a target
• Measure long-term clinical outcomes
• Ensure batch-to-batch manufacturing consistency
• Evaluate regulatory labeling requirements

Correct Answer: Rapidly test thousands of compounds for activity against a target

Q14. The hit-to-lead stage primarily aims to:

• Convert initial hits into optimized lead compounds with acceptable properties
• Finalize packaging design for marketing
• Recruit patients for Phase IV studies
• File the clinical trial registry only

Correct Answer: Convert initial hits into optimized lead compounds with acceptable properties

Q15. Pharmacokinetics (PK) studies measure which aspects of a drug?

• Absorption, distribution, metabolism and excretion characteristics
• Only pharmacodynamics at receptor level
• Commercial viability and market share
• Clinical trial recruitment rates

Correct Answer: Absorption, distribution, metabolism and excretion characteristics

Q16. Pharmacodynamics (PD) primarily describes:

• The drug’s biochemical and physiological effects and mechanism of action
• The process of scaling up production
• Regulatory submission timelines
• Stability of the drug product under accelerated conditions

Correct Answer: The drug’s biochemical and physiological effects and mechanism of action

Q17. Nonclinical toxicology studies intended for regulatory submission must follow:

• Good Laboratory Practice (GLP) standards
• Good Distribution Practice (GDP) guidelines only
• Marketing authorization rules
• Clinical trial informed consent procedures

Correct Answer: Good Laboratory Practice (GLP) standards

Q18. Which stage is typically the most expensive in the drug discovery process?

• Late-stage clinical trials (Phase III) due to scale and duration
• Target identification only
• Initial medicinal chemistry design
• Early in silico screening

Correct Answer: Late-stage clinical trials (Phase III) due to scale and duration

Q19. Biomarkers in drug discovery are used to:

• Indicate target engagement, efficacy or potential toxicity
• Replace all animal toxicology studies
• Define marketing price
• Serve as manufacturing excipients

Correct Answer: Indicate target engagement, efficacy or potential toxicity

Q20. Orphan drug designation is beneficial when developing drugs for:

• Rare diseases with small patient populations
• Common conditions with millions of patients
• Non-therapeutic cosmetic agents
• OTC vitamins only

Correct Answer: Rare diseases with small patient populations

Q21. Virtual screening in hit identification refers to:

• In silico docking and computational screening of compound databases
• Physical robotic screening of compounds only
• Clinical trial simulations
• Manufacturing process simulation

Correct Answer: In silico docking and computational screening of compound databases

Q22. Lead-likeness of a compound generally favors which properties?

• Low molecular weight and simple scaffolds amenable to optimization
• Very high molecular weight and high lipophilicity
• Complex natural extracts only
• Irreversible covalent binding always

Correct Answer: Low molecular weight and simple scaffolds amenable to optimization

Q23. Oral bioavailability is defined as:

• The proportion of an administered dose reaching systemic circulation unchanged
• The potency of a drug in vitro
• The marketing uptake after launch
• The time to reach maximum marketing share

Correct Answer: The proportion of an administered dose reaching systemic circulation unchanged

Q24. Which preclinical study is often performed first to assess immediate hazard?

• Acute toxicity (single-dose) studies in animals
• Phase III clinical efficacy trials
• Long-term epidemiological studies
• Large-scale manufacturing validation

Correct Answer: Acute toxicity (single-dose) studies in animals

Q25. For marketing approval in the US, which submission is required?

• New Drug Application (NDA)
• Investigational New Drug (IND) only
• Clinical Trial Authorization (CTA) for EU only
• Good Manufacturing Practice (GMP) certificate only

Correct Answer: New Drug Application (NDA)

Q26. A lead compound is best described as:

• A compound with desirable activity and properties for further optimization
• A final marketed drug product with full labeling
• Only a toxic metabolite
• A formulation excipient

Correct Answer: A compound with desirable activity and properties for further optimization

Q27. Structure–activity relationship (SAR) analysis helps scientists to:

• Understand how chemical modifications affect biological activity
• Determine marketing pricing strategies
• Replace clinical trials entirely
• Standardize packaging design

Correct Answer: Understand how chemical modifications affect biological activity

Q28. Which biophysical assay is commonly used to measure ligand–target binding affinity?

• Surface plasmon resonance (SPR) assay
• Phase I clinical endpoint
• Manufacturing yield test
• Accelerated stability test

Correct Answer: Surface plasmon resonance (SPR) assay

Q29. During lead optimization, which property is considered a major liability?

• High metabolic clearance leading to a very short half-life
• Moderate potency with good selectivity
• Balanced lipophilicity and solubility
• Predictable, low-toxicity profile

Correct Answer: High metabolic clearance leading to a very short half-life

Q30. Good Manufacturing Practice (GMP) in drug discovery ensures:

• Consistent quality and safety of drug products during manufacturing
• Improved target validation in vitro
• Faster in silico screening results
• Lowered biological assay sensitivity

Correct Answer: Consistent quality and safety of drug products during manufacturing

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