Relevance: GS Paper II – Health
For Prelims:
Keytruda (Pembrolizumab), Immunotherapy, Monoclonal Antibody, PD-1 receptor, PD-L1 pathway
For Mains:
- Cancer burden in India, access to life-saving drugs, immunotherapy revolution, affordability vs innovation, counterfeit drug markets, health governance gaps
Why in News?
- Keytruda (Pembrolizumab) has come into focus due to reports of a counterfeit drug market in India, driven by high cost and limited access.
- The issue highlights concerns related to drug affordability, regulatory gaps, and patient safety in India’s healthcare system.
What is Keytruda?
- Keytruda is an immunotherapy drug developed by Merck & Co. (MSD).
- It is used to treat multiple cancers such as:
- Lung cancer
- Cervical cancer
- Renal cell carcinoma
- Triple-negative breast cancer
- It was approved by the US FDA in 2014 and is now widely used globally.
- It is among the highest revenue-generating cancer drugs, reflecting its clinical effectiveness.
Scientific Mechanism
- Keytruda is a monoclonal antibody-based immune checkpoint inhibitor.
- It targets the PD-1 receptor on T-cells.
- Normally, cancer cells evade immunity by binding PD-L1 (on cancer cells) to PD-1 (on T-cells), which switches off immune response.
- Keytruda blocks this interaction → reactivates T-cells → enables immune system to attack cancer cells.
- This mechanism represents a shift from directly killing cancer cells to activating the body’s immune system.
Why Keytruda is a Breakthrough
- Unlike chemotherapy and radiation, it:
- Targets cancer selectively
- Minimises damage to healthy cells
- Provides long-term immune memory
- It has shown remarkable results in advanced-stage cancers, where traditional therapies often fail.
- It represents the core of modern cancer treatment paradigm: immunotherapy.
India-Specific Context
- India is witnessing a rising cancer burden, projected to reach 24.5 lakh cases by 2045.
- Keytruda costs over ₹3 lakh per month, making it inaccessible for most patients.
- To improve access:
- Government removed basic customs duty
- Company introduced Patient Access Programme (buy 5 doses → get 30 free)
- Despite these measures, affordability remains a major barrier.
Emerging Challenge: Counterfeit Drug Market
- High cost and demand have led to the emergence of fake Keytruda supply chains.
- Investigations revealed:
- Unauthorized distribution channels
- Weak hospital procurement oversight
- Patients unknowingly receiving counterfeit drugs
- This poses serious risks:
- Treatment failure
- Health complications
- Loss of trust in healthcare system
Broader Immunotherapy Landscape
- Keytruda is part of a larger shift towards precision and immune-based therapies:
- Checkpoint inhibitors → e.g., Keytruda
• CAR-T Cell Therapy → genetically modified T-cells attack cancer
• mRNA Cancer Vaccines → train immune system to recognise tumour antigens - These therapies represent the future of oncology, but are currently expensive.
Governance and Regulatory Issues
- Weak drug supply chain monitoring enables counterfeit markets.
- Lack of strict verification mechanisms in hospitals increases risk.
- High dependence on imports raises affordability concerns.
- Limited domestic innovation in advanced biologics restricts accessibility.
Way Forward
- Strengthen drug traceability systems using digital tracking and barcoding.
- Promote domestic production of biosimilars and biologics to reduce costs.
- Enhance regulatory oversight on hospital procurement and distribution chains.
- Expand public funding and insurance coverage for advanced cancer therapies.
- Invest in indigenous research in immunotherapy and precision medicine.
Conclusion
Keytruda represents a major advancement in cancer treatment by harnessing the immune system to fight disease. However, its high cost and the emergence of counterfeit markets reveal critical gaps in India’s healthcare system. Ensuring accessibility, affordability, and regulatory integrity will be essential to translate such medical breakthroughs into real public health gains.
CARE MCQ
Q. With reference to Keytruda, consider the following statements:
- It is a monoclonal antibody used in immunotherapy.
- It enhances immune response by blocking PD-1 receptors.
- It directly kills cancer cells like chemotherapy.
Which of the statements given above are correct?
A. 1 and 2 only
B. 2 and 3 only
C. 1 and 3 only
D. 1, 2 and 3
Answer: A
Explanation:
Statement 1 is correct because Keytruda is a monoclonal antibody-based immunotherapy drug.
Statement 2 is correct as it blocks PD-1 receptors, reactivating T-cells.
Statement 3 is incorrect because it does not directly kill cancer cells; instead, it activates the immune system.
Q. The primary target of Keytruda in the human body is:
(a) PD-L1 on tumor cells
(b) PD-1 receptor on T-cells
(c) CTLA-4 receptor
(d) HER2 protein
Answer: (b)
Explanation: Keytruda binds to PD-1 receptors on T-cells, preventing immune suppression by tumor cells.
Q. The interaction between PD-1 and PD-L1 in cancer biology leads to:
(a) Activation of immune response
(b) Suppression of T-cell activity
(c) Increased antibody production
(d) Enhanced cell division
Answer: (b)
Explanation: PD-1–PD-L1 binding switches off T-cells, allowing cancer cells to evade immunity.
Q.Which of the following cancers is/are treated using Keytruda?
- Lung cancer
- Cervical cancer
- Renal cell carcinoma
Select the correct answer:
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (d)
Explanation:
Keytruda (pembrolizumab) is a broad-spectrum immunotherapy drug belonging to the class of immune checkpoint inhibitors, specifically targeting the PD-1 receptor on T-cells. By blocking the PD-1 pathway, it prevents cancer cells from evading immune detection and allows the immune system to attack tumor cells effectively.
Its approval across multiple cancer types is based on tumor immunogenicity (ability to trigger immune response) rather than only tissue of origin, which marks a shift from traditional cancer treatment approaches.
FAQs
Q1. What type of drug is Keytruda?
It is an immunotherapy drug and immune checkpoint inhibitor.
Q2. How does Keytruda work?
It blocks PD-1 receptors on T-cells, enabling them to attack cancer cells.
Q3. Why is Keytruda important for India?
Because of rising cancer burden and need for advanced treatment options.
Q4. What is the main challenge associated with Keytruda in India?
High cost and emergence of counterfeit drug market.
Q5. What is the future of cancer treatment?
Immunotherapy, gene-based therapies, and precision medicine.
Relevance: GS Paper III – Environment, Energy, Health
For Prelims:
Improved Cookstoves (ICS), Thermal Efficiency, Biomass Fuel, Household Air Pollution (HAP), PM2.5, Carbon Credits
For Mains:
Clean cooking energy transition, energy poverty, affordability versus clean fuel access, household air pollution, climate-health linkage, sustainable biomass use
Why in News?
- Growing debate has emerged on whether Improved Cookstoves (ICS) can function as a cleaner and more affordable alternative to LPG, particularly in rural India.
- Rising LPG prices and concerns regarding energy affordability have revived interest in biomass-based cooking solutions that are locally available and cost-effective.
What are Biomass Stoves (ICS)
- Improved Cookstoves are advanced cooking devices designed to burn biomass fuels such as firewood, crop residues, pellets, and briquettes more efficiently.
- These stoves incorporate improved airflow mechanisms, especially secondary aeration, which ensures more complete combustion of fuel.
- As a result, they reduce smoke generation, improve heat utilization, and increase overall cooking efficiency
Performance Comparison: ICS vs Traditional vs LPG
- Traditional chulhas operate with very low thermal efficiency of around 10 percent, leading to high fuel consumption and excessive smoke emissions.
- In contrast, Improved Cookstoves achieve thermal efficiency levels between 38 percent and 45 percent
- It reduces fuel consumption by up to two-thirds and significantly lowering emissions.
- LPG, on the other hand, provides near-complete combustion with minimal indoor pollution but involves high recurring costs due to cylinder refills.
- Thus, ICS act as an intermediate solution that improves efficiency and reduces pollution compared to traditional stoves, while remaining more affordable than LPG
Environmental and Health Impact
- Traditional biomass burning contributes to severe household air pollution, exposing users to harmful pollutants such as PM2.5 and carbon monoxide.
- Improved Cookstoves reduce the emission of these pollutants along with black carbon, which is a major climate forcer.
- This leads to measurable health benefits, including reduced incidence of respiratory diseases, eye irritation, and cardiovascular stress.
- Additionally, reduced fuel consumption lowers pressure on forest resources and contributes to environmental sustainability
Economic Viability and Cost Comparison
- The cost of household-level Improved Cookstoves generally remains below ₹2,000, while larger commercial models may cost up to ₹20,000.
- In comparison, LPG involves continuous expenditure on cylinder refills.
- Since ICS rely on locally available biomass and reduce fuel consumption by more than 50 percent, they offer a cost-effective alternative for low-income households, especially in rural areas
Sustainability of Biomass Use
- Biomass can be considered a sustainable fuel only when the rate of extraction does not exceed the rate of natural regeneration.
- Improved Cookstoves enhance sustainability by reducing fuel demand and promoting efficient utilization of biomass resources.
- However, unregulated or excessive extraction of firewood can still lead to deforestation and ecological imbalance
Role of Carbon Credits
- Improved Cookstoves contribute to emission reduction and are therefore eligible for carbon credit financing.
- Each reduction in greenhouse gas emissions can be monetised in carbon markets, allowing projects promoting ICS to generate revenue.
- This revenue can be used to subsidise the cost of stoves and expand their adoption among economically weaker sections
Challenges in Adoption
- Adoption of Improved Cookstoves faces several challenges.
- Cultural preferences for traditional cooking methods often limit acceptance.
- Maintenance requirements, such as periodic cleaning and part replacement, can discourage continued usage.
- Distribution networks in rural areas remain weak, and lack of awareness regarding long-term health benefits further slows adoption.
- Additionally, pellet-based ICS require a reliable and organised fuel supply chain
Way Forward
Efforts should focus on strengthening last-mile distribution networks to ensure availability of ICS in rural areas. Integration with government clean cooking initiatives can accelerate adoption. Carbon financing and corporate social responsibility funds can be leveraged to subsidise costs. Design improvements should ensure compatibility with local cooking practices, while awareness campaigns must highlight the health and economic benefits of switching to improved stoves
Conclusion
Improved Cookstoves provide a practical transitional solution between traditional biomass use and modern clean fuels like LPG. While they significantly reduce emissions and improve efficiency, they do not fully eliminate indoor air pollution. A balanced strategy combining LPG expansion, ICS adoption, and behavioural change is essential to achieve universal access to clean cooking energy in India
CARE MCQ
Q. With reference to Improved Cookstoves (ICS), consider the following statements-
- They significantly improve thermal efficiency compared to traditional chulhas
- They completely eliminate indoor air pollution
- They can be linked with carbon credit mechanisms
Which of the statements given above are correct
A. 1 and 3 only
B. 1 and 2 only
C. 2 and 3 only
D. 1, 2 and 3
Answer : (a)
Explanation:
Statement 1 is correct because ICS increase thermal efficiency from about 10 percent to nearly 40 percent or more
Statement 2 is incorrect because ICS reduce but do not completely eliminate indoor air
pollution
Statement 3 is correct because emission reductions from ICS can be monetised through carbon credit markets.
Q. Which of the following pollutants is primarily responsible for the formation of photochemical smog?
(a) Sulphur dioxide
(b) Nitrogen oxides and volatile organic compounds
(c) Carbon monoxide
(d) Particulate matter
Answer: (b)
Explanation: Photochemical smog forms when nitrogen oxides (NOx) react with volatile organic compounds (VOCs) in the presence of sunlight, producing secondary pollutants like ozone and PAN. It is typical of urban areas with heavy vehicular emissions.
Q. The major source of sulphur dioxide (SO₂) in urban air pollution is:
(a) Vehicular emissions
(b) Coal-based thermal power plants
(c) Agricultural activities
(d) Construction dust
Answer: (b)
Explanation: SO₂ is mainly emitted from burning of sulphur-containing fossil fuels, especially coal in thermal power plants.
Q. Which of the following is/are secondary air pollutants?
- Ozone
- Peroxyacetyl nitrate (PAN)
- Carbon monoxide
Select the correct answer:
(a) 1 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
Answer: (b)
Explanation: Ozone and PAN are secondary pollutants formed through atmospheric reactions. Carbon monoxide is a primary pollutant directly emitted from incomplete combustion.
FAQs
Q1 What makes Improved Cookstoves different from traditional chulhas?
They use better airflow and combustion techniques, resulting in higher efficiency and lower emissions
Q2 Are biomass stoves cleaner than LPG?
They are cleaner than traditional stoves but still not as clean as LPG
Q3 Why are ICS important for India?
They address energy poverty, reduce pollution, and provide a low-cost cooking solution for rural households
Q4 How do ICS contribute to climate change mitigation?
By reducing emissions such as black carbon and enabling carbon credit generation
Q5 Can ICS fully replace LPG?
They act as a complementary and transitional solution rather than a complete replacement for LPG
