Science & TechnologyPriority2026-02-12

WHO Prequalification for nOPV2 Vaccine

Why focus: GS3 S&T — oral polio vaccine technology (nOPV2) and WHO prequalification. Tests biological concepts and manufacturer proxies.

In News

What Happened

On February 12, 2026, the World Health Organization (WHO) granted Phase II Prequalification to India's Biological E. Limited for its novel oral polio vaccine type 2 (nOPV2). This elevates the company from merely bottling the vaccine to fully manufacturing both the active drug substance and the final product at a single site in Hyderabad. Biological E is now the world's second full end-to-end manufacturer of this vaccine.

Why It Matters

This breakthrough provides a massive, reliable global supply of nOPV2, with Biological E expected to produce 600 million doses annually. It gives United Nations agencies like UNICEF and the Global Polio Eradication Initiative (GPEI) a critical, stabilized tool to fight circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreaks, predominantly in Africa, while cementing India's status as a leader in global vaccine manufacturing.

Background

History & Context

The global fight against polio achieved a major milestone in 2015 when wild poliovirus type 2 was declared eradicated. Consequently, in 2016, the world switched from trivalent to bivalent oral polio vaccine (OPV) for routine immunization to avoid the risks associated with the live-attenuated type 2 Sabin strain. However, in areas with low immunization, the older Sabin type 2 vaccine virus mutated and regained neurovirulence, causing escalating circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreaks. To counter this, a consortium including PATH, the Bill & Melinda Gates Foundation, and NIBSC developed nOPV2, a genetically stabilized version. In late 2020, nOPV2 became the first vaccine ever to receive a WHO Emergency Use Listing (EUL). Indonesia's PT Bio Farma became the first manufacturer to receive full WHO prequalification in January 2024. Biological E joined the effort, receiving Phase I prequalification in June 2024 before advancing to full Phase II status in early 2026.

What Changed

▶
Manufacturing Scope: BEFORE, under its June 2024 Phase I prequalification, Biological E only performed 'fill-finish' operations using bulk drug substance imported from Indonesia's PT Bio Farma. NOW, under Phase II, Biological E manufactures both the Drug Substance and Drug Product at a single integrated site in India.
▶
Global Supply Chain Vulnerability: BEFORE, the world relied heavily on a single full manufacturer (PT Bio Farma) for end-to-end production of nOPV2. NOW, global production is diversified with two independent suppliers, highly reducing bottleneck risks during sudden outbreaks.
▶
Production Capacity for Outbreak Response: BEFORE, the Global Polio Eradication Initiative (GPEI) faced potential supply constraints for specialized vaccines. NOW, Biological E's expanded approval allows it to pump an additional 600 million doses per year into the global stockpile.
▶
Viral Stability in the Field: BEFORE (using older mOPV2), outbreak response vaccines frequently lost their attenuating mutations in the gut, seeding new vaccine-derived outbreaks. NOW, the widespread use of nOPV2 provides a tool that is 80% less likely to revert to neurovirulence due to targeted genetic modifications.

What Did NOT Change

The fundamental mechanism of action of the vaccine remains unchanged; nOPV2 is still a live, attenuated oral vaccine that replicates in the human gut to induce critical primary intestinal mucosal immunity, unlike injectable killed vaccines. Furthermore, nOPV2 remains strictly categorized as an outbreak response tool—it has not replaced bivalent OPV or IPV in the daily, routine Universal Immunization Programme globally.

Prelims Angle

NCERT Connection

This event directly applies the concepts found in Class 12 Biology, Chapter 8 (Human Health and Disease), specifically the section on 'Immunity' and 'Vaccination and Immunisation'. The chapter explains how vaccines use weakened (attenuated) pathogens to generate memory B and T cells. The development of nOPV2 takes this a step further: scientists genetically engineered the primary attenuation sites of the live Sabin virus so that while it still triggers the immune response described in NCERT, it is structurally blocked from mutating back into a disease-causing pathogen in the host's body.

Common Misconceptions

✗ Vaccine-derived poliovirus outbreaks are caused by the Inactivated Polio Vaccine (IPV) mutating in children's bodies.

✓ Vaccine-derived poliovirus ONLY arises from the Oral Polio Vaccine (OPV), which contains a live, weakened virus capable of replicating and mutating in the gut. IPV contains a dead/killed virus that cannot mutate or cause disease.

The general public often assumes all vaccines work the same way and carry the risk of causing the disease they are meant to prevent, failing to distinguish between live-attenuated and inactivated mechanisms.

✗ nOPV2 is now being given to all children globally as part of routine daily immunization.

✓ nOPV2 is strictly reserved as an outbreak-response tool, deployed only in targeted regions actively experiencing circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreaks.

People confuse specialized emergency stockpiles with routine Universal Immunization Programme (UIP) vaccines, which currently rely on bivalent OPV and IPV for daily prevention.

Practice Questions

Q1

How Many Correct

Consider the following statements regarding the Novel Oral Polio Vaccine type 2 (nOPV2) and its WHO Prequalification: 1. nOPV2 holds the distinction of being the first vaccine in history to receive a WHO Emergency Use Listing (EUL). 2. India's Biological E. Limited is the first company in the world to receive end-to-end Phase II manufacturing WHO prequalification for nOPV2. 3. nOPV2 eliminates the risk of vaccine-derived poliovirus by utilizing an inactivated, killed virus that cannot replicate in the human gut. How many of the statements given above are correct?

Q2

Match the Following

Match List I (Vaccine Type) with List II (Characteristic/Use) regarding the global polio eradication strategy: List I: A. mOPV2 (Monovalent OPV2) B. nOPV2 (Novel OPV2) C. IPV (Inactivated Polio Vaccine) D. bOPV (Bivalent OPV) List II: 1. Replaced the trivalent vaccine in routine global immunization schedules in 2016. 2. First vaccine to ever receive the WHO Emergency Use Listing (EUL). 3. Traditional outbreak response tool that was frequently prone to seeding new cVDPV2 outbreaks. 4. Administered via injection; provides excellent systemic immunity but poor gut mucosal immunity. Select the correct answer using the code given below:

Q3

Assertion & Reason

Assertion (A): The traditional Sabin monovalent oral polio vaccine type 2 (mOPV2) is currently the preferred tool by the WHO for routine response to circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreaks. Reason (R): The live attenuated virus in traditional OPV can genetically mutate in under-immunized populations, regain neurovirulence, and cause paralysis. Select the correct answer from the codes given below:

Up next