Myth Meets Molecules · Pharmacoeconomics

1

What is Pharmacoeconomics?

Definition, core problem, and where PE is used

1.1Definition & The Core Problem

▼

Standard Definition: Pharmacoeconomics is the branch of health economics that identifies, measures, and compares the costs and consequences of pharmaceutical products and services to guide optimal healthcare resource allocation. (Bootman et al.)

The Core Problem: Scarcity & Opportunity Cost

Scarcity: No country has unlimited money for healthcare. Every rupee spent on one medicine is a rupee NOT spent elsewhere.
Opportunity cost: the value of the next-best option you give up
Indian context: Government of India spends ~₹1,600/person/year on health. A single cancer drug course = ₹5–10 lakhs. PE decides whether that trade-off is worth it.
In one line: The medicine that gives the MOST HEALTH for the LEAST MONEY wins. PE is the toolkit to find that winner.

1.2Where is Pharmacoeconomics Used?

▼

Hospital Formulary Committees: 'Should we add this new expensive antibiotic to our drug list?'
National Drug Policy: 'Should the government include this vaccine in the Universal Immunisation Programme?'
Insurance Companies: 'Which treatment should we reimburse?'
Drug Regulatory Agencies: 'Is this new drug's price justified?' (HTA — Health Technology Assessment)
Pharmaceutical Companies: 'How do we prove our drug's value in a price negotiation with government?'
Clinicians: 'Among equally effective drugs, which gives the most value to my patient?'

2

Types of Costs & Perspectives

Four cost types and four study perspectives — choosing the right one changes the conclusion

2.1Four Types of Costs

▼

Type	What It Includes	Indian Example
1. Direct Medical	Medicine price, doctor fees, lab tests, hospital stay, nursing, procedures	₹500/month metformin + ₹300 HbA1c test + ₹5000/day ICU
2. Direct Non-Medical	Transport to hospital, meals during treatment, caregivers' expenses	₹200 auto fare, lodging for family during admission
3. Indirect (Productivity Loss)	Wages lost because patient can't work, family member takes leave	Diabetic farmer loses 20 working days = ₹8000 lost income
4. Intangible	Pain, suffering, anxiety, reduced QoL — hard to quantify	Depression from chronic illness, stigma of HIV/TB

Exam Tip: Direct Medical costs = most commonly used. Societal perspective studies include ALL four types — most comprehensive but most complex.

2.2Perspectives & Key Concepts

▼

Perspective	Who Is It?	Costs Included	Example Use
Patient	Individual sick person	Out-of-pocket, travel, lost wages	Should I buy the expensive branded drug?
Hospital / Provider	Hospital or clinic	Drug acquisition, staff time, equipment	Hospital formulary decisions
Payer / Insurer	Insurance co. / Government scheme	What is reimbursed	PMJAY, ESI, private insurance formulary
Societal	All of society combined	ALL costs: direct + indirect + intangible	National health policy, disease burden studies

Critical Rule: Always state the perspective at the START of any PE analysis. Changing the perspective can completely change the conclusion of a study!

Other Key Concepts

Discounting: Money today is worth MORE than money in the future. Standard discount rate in India: 3–5%. PV = FV / (1 + r)ⁿ
Average Cost: Total Cost ÷ Total Units. Marginal Cost: Cost of treating ONE more patient (usually lower than average — fixed costs already paid).

3

The Five Pharmacoeconomic Methods

CMA · CEA · CUA · CBA · COI — each measures value differently

Think of the five methods as five different RULERS for measuring value. Each ruler measures a different thing. You pick the ruler based on what your outcomes look like and what question you're trying to answer.

Method	Question Answered	Outcome Unit	When to Use	Key Formula
CMA	Which is cheaper if outcomes are equal?	Money only (₹)	Proven equivalent outcomes (generics, biosimilars)	Compare costs directly
CEA	How much does one extra unit of clinical outcome cost?	₹ per clinical unit (mmHg, LY, % cured)	Same disease, different efficacy	ICER = ΔCost / ΔEffect
CUA	How much does one QALY or DALY cost?	₹ per QALY or ₹ per DALY averted	Comparing across diseases; QoL matters	ICER = ΔCost / ΔQALY; QALY = Utility × Time
CBA	Do monetary benefits outweigh monetary costs?	Money (₹) for both costs AND benefits	Public health policy; health vs. non-health	BCR = Benefits / Costs
COI	What is the total economic burden of this disease?	Total ₹ per year	Burden assessment — NOT a comparison	COI = Direct + Indirect + Intangible

CMACost-Minimization Analysis — 'Just Tell Me the Cheaper One'

▼

Compares two treatments already proven to give IDENTICAL outcomes. Cheaper one wins.
Unit: MONEY ONLY (₹) — no outcome measurement needed beyond confirming equivalence
Most common in generic vs. branded drug comparisons

Indian Example

→Branded Amoxicillin 500mg: ₹12/tablet. Generic: ₹3/tablet. Both bioequivalent.

→CMA picks generic: saves ₹9 × 21 tablets = ₹189 per course. Crores saved nationally.

⚠️ CMA Trap: CMA is ONLY valid when equivalence has been PROVEN. If two drugs are just 'similar' without solid evidence → use CEA instead.

CEACost-Effectiveness Analysis — 'How Much Does One Unit of Health Cost?'

▼

Compares treatments with different outcomes in natural clinical units (mmHg, HbA1c%, LY gained, cases cured)
Most commonly used PE method

Key Formulae

ACER = Total Cost / Total Effectiveness ICER = (Cost_New − Cost_Old) / (Effect_New − Effect_Old) = ΔCost / ΔEffect

ACER vs ICER: ACER = value of a drug ALL BY ITSELF ("what is the price of this item?"). ICER = extra cost for extra benefit COMPARED TO the current standard ("how much more for the upgrade?").

The Cost-Effectiveness Plane — 4 Quadrants

Quadrant	ΔCost	ΔEffect	Interpretation	Decision
I — Trade-off (NE)	Higher (+)	Better (+)	More costly but more effective — calculate ICER	Conditional Yes
II — Dominant (SE)	Lower (−)	Better (+)	Cheaper AND better — no calculation needed	Always YES
III — Trade-off (SW)	Lower (−)	Worse (−)	Cheaper but less effective	Conditional
IV — Dominated (NW)	Higher (+)	Worse (−)	More expensive AND worse	Always NO

CUACost-Utility Analysis — 'How Much Does One Year of Good Life Cost?'

▼

Outcome measured in QALYs or DALYs — captures BOTH quantity AND quality of life
Used by HTA bodies worldwide (NICE in UK, PBAC in Australia, HTAIn in India)
Allows comparison across DIFFERENT diseases and treatments

QALY Formula

QALY = Utility Score (0–1) × Time (years) ICER_CUA = ΔCost / ΔQALY DALY = YLL + YLD (Years of Life Lost + Years Lived with Disability)

Utility Score Reference

Health State	Utility Score	1 Year =
Perfect health	1.0	1.0 QALY
Mild angina	0.80	0.80 QALY
Moderate COPD	0.60	0.60 QALY
Dialysis patient	0.45	0.45 QALY
Severe stroke	0.20	0.20 QALY
Dead	0.0	0 QALY

Willingness to Pay (WTP) Threshold

Decision rule: If ICER < WTP threshold → Cost-Effective → ADOPT
Decision rule: If ICER > WTP threshold → NOT Cost-Effective → REJECT / renegotiate
India WTP: No official declared threshold. Academic consensus = 1–3× GDP per capita. India GDP per capita ≈ ₹1.5–1.8 lakhs/year → India informal WTP = ₹1.5 to ₹5.4 lakhs/QALY
UK NICE WTP: £20,000–£30,000/QALY
HTAIn (Health Technology Assessment in India, est. 2017): informally uses 1× to 3× GDP per capita

QALY vs DALY: QALY = gains, used by HTA bodies (NICE). DALY = losses, used by WHO/GBD. QALYs are patient-reported (subjective). DALYs are calculated from epidemiological data (population-level).

CBACost-Benefit Analysis — 'Is the Money Returned as Money?'

▼

Translates BOTH costs AND outcomes (benefits) into MONEY
Common for vaccination programmes and public health interventions

Key Formulae

BCR = Total Benefits (₹) / Total Costs (₹) Net Benefit = Total Benefits − Total Costs BCR > 1 → Worthwhile. BCR < 1 → Not worthwhile.

Indian Example — Hepatitis B Vaccination

1Cost of vaccinating all Indian newborns/year = ₹800 crore

2Benefits (averted liver disease + hospital costs + lost productivity) = ₹4500 crore

3BCR = 4500 / 800 = 5.6 → ₹5.60 returned per ₹1 spent

4Net Benefit = ₹4500 − ₹800 = ₹3700 crore net gain

∴ BCR = 5.6 — clearly worthwhile → Hep B in Universal Immunisation Programme

⚠️ Limitation: Biggest challenge in CBA: converting human lives and quality of life into money. Human capital approach (wage value) and WTP surveys are used but controversial. This is why CUA (using QALYs) is often preferred.

COICost of Illness — 'How Much Does This Disease Cost Society?'

▼

NOT a decision-making tool — does NOT compare two treatments
Calculates the total economic burden of a specific disease on society
Sets the MAXIMUM reasonable cost a treatment should have (treatment cannot logically cost MORE than the disease itself)
Justifies investment in prevention or treatment programmes

Formula

COI = Direct Medical + Direct Non-Medical + Indirect + Intangible

Indian Example — Diabetes COI: ~100 million diabetics (2023). Annual direct medical cost per patient: ₹8,000–₹25,000. Total COI for diabetes in India: ₹3.5–5 lakh crore/year → justifies massive government investment in NPCDCS.

Ex.1

Exercise — Case-Based CEA: Antihypertensive Drug Comparison

Drug A vs Drug B — ACER, ICER, and formulary decision

CEAFull Worked Solution — BP Drug Comparison

▼

Given

Parameter	Drug A	Drug B
Cost per month	₹600	₹900
BP control rate	80%	90%
Annual complication cost	₹2,000	₹1,200

Task 1: Annual Total Cost

1Annual drug cost: Drug A = ₹600 × 12 = ₹7,200/yr; Drug B = ₹900 × 12 = ₹10,800/yr

2Total annual cost: Drug A = ₹7,200 + ₹2,000 = ₹9,200/yr; Drug B = ₹10,800 + ₹1,200 = ₹12,000/yr

Task 2: ACER

3ACER (Drug A) = ₹9,200 / 0.80 = ₹11,500 per controlled patient

4ACER (Drug B) = ₹12,000 / 0.90 = ₹13,333 per controlled patient

5Drug A is MORE cost-effective (lower cost per success) → ₹11,500 < ₹13,333

Task 3: ICER (Drug B vs Drug A)

6ΔCost = ₹12,000 − ₹9,200 = ₹2,800/yr

7ΔEffect = 90% − 80% = 10% (= 0.10)

8ICER = ₹2,800 / 0.10 = ₹28,000 per additional controlled patient

∴ Drug A wins: ACER ₹11,500 vs ₹13,333. ICER of switching to Drug B = ₹28,000/extra controlled patient.

Non-Monetary Factors in Real-World Drug Selection

Compliance/Adherence: a drug patients actually take is worth more than a 'superior' drug they stop due to side effects
Side effect profile: ACE inhibitor cough → patient discontinues → all cost savings lost
Quality of life: Drug B causing less fatigue = indirect benefit not captured in ACER
Disease severity: higher-risk patients (previous MI, diabetic) may justify extra cost
Availability: In rural India, Drug A at local PHC; Drug B requires city hospital

Ex.2

Exercise — CUA: Methotrexate vs Etanercept in RA

QALY-based ICER calculation, WTP threshold decision, and policy implications

CUAFull Worked Solution — Etanercept vs Methotrexate

▼

Given — WTP threshold = ₹1,50,000/QALY

Drug	Cost/year	QALYs gained
Methotrexate	₹12,000	0.8
Etanercept	₹2,40,000	2.5

ACER Calculations

1ACER (MTX) = ₹12,000 / 0.8 = ₹15,000/QALY (very cost-effective)

2ACER (Etanercept) = ₹2,40,000 / 2.5 = ₹96,000/QALY

ICER Calculation — Step by Step

3ΔCost = ₹2,40,000 − ₹12,000 = ₹2,28,000/yr

4ΔQALY = 2.5 − 0.8 = 1.7 QALYs gained

5ICER = ₹2,28,000 / 1.7 = ₹1,34,118 per additional QALY

Decision: Is Etanercept Cost-Effective?

6ICER (₹1,34,118) < WTP threshold (₹1,50,000) → YES — cost-effective!

7Falls in Quadrant I, below the WTP threshold line → Acceptable zone

∴ ICER = ₹1,34,118/QALY < ₹1,50,000 WTP → Etanercept is cost-effective (borderline)

⚠️ Borderline Case: ICER is close to threshold. Any increase in price or drop in QALY gain could push it above ₹1,50,000. This is where sensitivity analysis is CRITICAL.

Balanced Policy Recommendation

Include Etanercept but with restricted criteria: (1) Reserve for patients who failed ≥2 conventional DMARDs; (2) Mandatory TB screening (IGRA/TST) — India has the world's highest TB burden; (3) Annual reassessment of response; (4) Explore government subsidy; (5) Consider Indian biosimilar (Etacept, Intacept at ₹6,000–8,000/month → ICER ≈ ₹33,000–43,000/QALY — highly cost-effective!).

Ex.3

Critical Appraisal of a PE Study

Drummond 10-question checklist + Formulary Decision: Ceftriaxone vs Cefotaxime

AppraisalDrummond 10-Question Checklist

▼

#	Question to Ask	What to Look For	Common Problem
1	Was a well-defined question posed?	Clear comparators, perspective, population	Vague objectives, undeclared perspective
2	Were alternatives comprehensively described?	Dose, duration, setting for both arms	One arm poorly described or unrealistic
3	Was effectiveness established?	RCTs, meta-analysis, or observational data	Surrogate endpoints instead of hard outcomes
4	Were all costs identified and measured?	All relevant costs for stated perspective	Missing indirect costs, administration costs
5	Were outcomes measured and valued appropriately?	QALYs with validated instrument (EQ-5D)	Western utility values applied to India
6	Were costs and outcomes adjusted for time?	Discounting applied (3–5%) for >1 year studies	No discounting in long-term studies
7	Was incremental analysis performed?	ICER reported; dominant/dominated identified	Only ACER reported; no ICER
8	Was a sensitivity analysis performed?	One-way, multi-way, or PSA; tornado diagram	Only point estimates; no uncertainty explored
9	Were equity concerns discussed?	Distribution of costs across socioeconomic groups	Expensive drug recommended without acknowledging access inequity
10	Did conclusions follow from data?	Recommendations justified; limitations acknowledged	Industry-funded study with spin toward sponsor's product

CMA Ex.Formulary Decision: Ceftriaxone vs Cefotaxime

▼

Parameter	Ceftriaxone	Cefotaxime
Dosing	1g ONCE daily	1g 8-hourly (TID — 3 doses/day)
Cost per day (generic)	₹80–120 × 1 = ₹80–120/day	₹35–60 × 3 = ₹105–180/day
IV sets/day	1 IV set/day	3 IV sets/day (₹90–150/day)
Nursing time	~10 min/day	~30 min/day
Medication errors risk	Lower (once-daily)	Higher (timing errors)
⚠️ Neonatal use	CONTRAINDICATED (Ca²⁺ precipitation)	Safe with Ca²⁺ solutions — preferred in neonates

CMA: Total Cost per 5-Day Course

1Drug cost: Ceftriaxone ₹80×5 = ₹400; Cefotaxime ₹50×3×5 = ₹750

2IV set cost: Ceftriaxone ₹40×1×5 = ₹200; Cefotaxime ₹40×3×5 = ₹600

3Nursing (₹30/hr): Ceftriaxone (10/60)×₹30×5 = ₹25; Cefotaxime (30/60)×₹30×5 = ₹75

4TOTAL: Ceftriaxone = ₹625; Cefotaxime = ₹1,425

5Savings with Ceftriaxone = ₹1,425 − ₹625 = ₹800 per course

∴ Ceftriaxone preferred: ₹625 vs ₹1,425 per 5-day course — once-daily dosing wins on total cost, nursing burden, and error reduction. EXCEPTION: neonatal meningitis → Cefotaxime.

9

Sensitivity Analysis

Types, tornado diagrams, and CEAC — making results believable

Type	What It Does	Visualised As	Best For
One-Way (Univariate)	Varies ONE parameter, keeps others fixed	Tornado diagram	Identifying most influential parameter
Two-Way (Bivariate)	Varies TWO parameters simultaneously	2D grid table	Exploring interaction between two key parameters
Threshold Analysis	Finds the exact value at which decision changes (ICER = WTP)	Single number	'At what price does this drug become cost-effective?'
Probabilistic (PSA)	Monte Carlo simulation (10,000+ iterations) — assigns distributions to all parameters	Scatter plot, CEAC	Gold standard for uncertainty analysis

SATornado Diagram & CEAC — Etanercept Example

▼

Tornado Diagram — Etanercept Study

Parameter	ICER if LOW	ICER if HIGH	Influence
Etanercept price	₹67,000/QALY	₹2,00,000/QALY	← ← ← ← ← (WIDEST — most important)
QALY gain (1.2–2.1)	₹1,09,524/QALY	₹1,90,000/QALY	← ← ← ←
Discount rate (0–10%)	₹1,20,000/QALY	₹1,55,000/QALY	← ← ←
Complication rate	₹1,30,000/QALY	₹1,38,000/QALY	← ←

Conclusion: Price is the MOST IMPORTANT uncertain parameter → price negotiation with manufacturer is the highest-priority policy action.

CEAC (Cost-Effectiveness Acceptability Curve)

After PSA: shows at each WTP threshold, the probability that the drug is cost-effective
At WTP = ₹50,000/QALY → probability ≈ 20%
At WTP = ₹1,34,118/QALY (= our ICER) → probability ≈ 50%
At WTP = ₹3,00,000/QALY → probability = 90%

11

All Formulae at a Glance + High-Yield Exam Facts

Complete formula reference and one-liners for the exam

Formula	Expression	Notes
Cost-Effectiveness Analysis (CEA)
ACER	`Total Cost / Total Effectiveness`	Single-drug value metric
ICER	`(Cost_New − Cost_Old) / (Effect_New − Effect_Old)`	Incremental value of switching
Cost-Utility Analysis (CUA)
QALY	`Utility Score (0–1) × Time (years)`	Dead = 0, perfect health = 1
ICER (CUA)	`ΔCost / ΔQALY`	ADOPT if ICER < WTP; REJECT if ICER > WTP
DALY	`YLL + YLD`	1 DALY = 1 healthy year of life LOST
NMB	`(WTP × ΔEffect) − ΔCost`	NMB > 0 → cost-effective. Preferred for PSA.
Cost-Benefit Analysis (CBA)
BCR	`Total Benefits (₹) / Total Costs (₹)`	BCR > 1 → worthwhile
Net Benefit	`Total Benefits − Total Costs`	Positive = worthwhile
Other Formulae
COI	`Direct Medical + Direct Non-Medical + Indirect + Intangible`	Burden only — no comparison
Total Cost (multiple dosing)	`Drug Cost + Admin Cost + Complication Cost + Monitoring Cost`	For formulary analysis
Present Value	`PV = FV / (1 + r)ⁿ`	r = discount rate; n = years
ACER (per success)	`Total Cost / Probability of Success`	e.g. Drug A = ₹9,200 / 0.80 = ₹11,500

High-Yield One-Liners for the Exam

CMA = Only costs compared → outcomes MUST be pre-proven equivalent
CEA outcome = Natural clinical units (mmHg, HbA1c%, life-years, cases cured)
CUA outcome = QALYs or DALYs — ONLY method that adjusts for quality of life
CBA = Both costs AND benefits in MONEY → gives BCR
COI = Burden only, NO comparison, NO decision needed
ICER < WTP threshold → cost-effective → ADOPT
ICER > WTP threshold → not cost-effective → REJECT / price negotiate
QALY = utility × years; dead = 0, perfect health = 1
DALY = years of healthy life LOST; 1 DALY = 1 healthy year lost
India WTP ≈ 1–3× GDP per capita = ₹1.5–5.4 lakhs/QALY (HTAIn guideline)
UK NICE WTP = £20,000–30,000/QALY
Dominant option = lower cost AND better outcome → always adopt without ICER
Dominated option = higher cost AND worse outcome → never adopt
Tornado diagram = identifies MOST IMPORTANT uncertain parameter
PSA with Monte Carlo simulation = gold standard for uncertainty analysis
Societal perspective = most comprehensive; payer = most commonly used in practice
Discounting needed for studies >1 year; standard rate 3–5%
Etanercept ICER = ₹2,28,000/1.7 QALYs = ₹1,34,118/QALY (< ₹1,50,000 WTP → cost-effective)
Drug A ACER = ₹9,200/0.80 = ₹11,500 | Drug B ACER = ₹12,000/0.90 = ₹13,333 → Drug A wins
Ceftriaxone wins formulary: ₹625 vs ₹1,425 per 5-day course — once-daily dosing

ICER Decision Rule: Think of WTP as the 'maximum price tag' society puts on one QALY. ICER is what you're actually paying. If actual (ICER) < max (WTP) → acceptable. If actual > max → reject.

5 Methods Memory: CMA = Costs only (Clinically equivalent) · CEA = Clinical units · CUA = Utility (QALYs) · CBA = Both in cash · COI = Cost Only, Illness burden → 'Five Cs of PharmEcon'

India DALY Burden — Key Exam Data

Disease	Approx. DALYs/year (India)	PE Implication
Ischemic Heart Disease	~30 million	Justifies generic statins, aspirin, beta-blockers in all PHCs
Lower Respiratory Infections	~25 million	Pneumococcal vaccine CE extensively studied
Tuberculosis	~5 million	DOTS programme — one of the most CE interventions globally
Diabetes Mellitus	~10 million	Metformin remains most cost-effective first-line agent
Malaria	~2 million	ACT (artemisinin combination therapy) — highly CE
Road Injuries	~8 million	Road safety policy (seatbelts, helmets) = most CE 'intervention'

PharmacoeconomicsCost, Value & Decisions