Misbranded rabies vaccines seized in Delhi: What was found, why it matters

Delhi authorities seized suspect Abhayrab vials from an unlicensed flat; samples failed potency tests and differed from genuine stock, prompting a regulatory alert

Last week, the Central Drugs Standard Control Organisation (CDSCO) alerted states and Union territories over the seizure of misbranded Abhayrab rabies vaccine bearing batch number KE25012 in Delhi, after samples failed a government laboratory's potency test.

 

The development has put one of India's widely used rabies vaccines under regulatory scrutiny, with authorities investigating the source and distribution of the suspect vials. The regulator said drug and law-enforcement agencies were maintaining “strict and continuous surveillance” against the illegal manufacture, distribution and supply of misbranded and spurious drugs.

What happened in Delhi?

The Abhayrab vials were seized on April 22 from an unlicensed residential premises in Mukherjee Nagar during a search by the Delhi Police Crime Branch and Delhi government drug inspectors.

 

 

The operation was part of a wider investigation into an alleged interstate racket involving the diversion, relabelling and sale of medicines. The police said in May that four people had been arrested and pharmaceutical products worth about ₹6 crore recovered.

 

The products under scrutiny included rabies vaccines, insulin, hepatitis-B vaccines, human albumin and snake antivenom. Police alleged that some medicines meant for government institutions were being stripped of identifying information and repackaged for unauthorised sale.

 

CDSCO subsequently collected samples of the Abhayrab vials and sent them to the Central Drugs Laboratory (CDL) in Kasauli for testing.

What did the laboratory find and why does it matter?

A Reuters report published on September 5 cited a government document and claimed that the field sample did not meet prescribed potency requirements and was classified by the CDL as both “Not of Standard Quality”, or NSQ, and “misbranded”. According to The Drugs and Cosmetics Act, 1940, a misbranded drug is one whose labelling does not comply with prescribed requirements or contains false or misleading information. Not of Standard Quality, or NSQ, means that a tested product has failed one or more prescribed quality specifications.

 

In this case, the failed parameter was potency, which measures whether a vaccine has sufficient biological activity to produce the intended protective immune response. For modern cell-culture rabies vaccines, WHO standards require a potency of at least 2.5 international units per intramuscular human dose.

 

This matters because a vaccine can appear genuine and pass several quality checks while still failing on the parameter that determines whether it has enough strength to protect the recipient.

 

The stakes are particularly high with rabies because it is almost 100 per cent fatal once clinical symptoms appear and there is no reliably effective treatment once the disease reaches the symptomatic stage. Post-exposure prophylaxis, or PEP, is given after a potentially infectious animal bite or scratch to prevent the virus from developing into disease.

What has IIL said?

Indian Immunologicals Ltd (IIL), which makes Abhayrab through its Human Biologicals Institute division, has said the seized vials were not manufactured by the company.

 

In a statement on September 4, IIL said the CDL found 17 differences between the questioned vials and its genuine retention samples from the same batch. These included differences in labelling, artwork, QR-code verification, vial-cap colour, licence information and packaging text. Retention samples are genuine samples kept aside from a manufacturing batch so they can later be used to check the quality or authenticity of the product.

 

IIL says the discrepancies show that the seized vials did not come from its manufacturing facility. The company has asked authorities to establish who produced or relabelled them and how they came to carry the details of a genuine Abhayrab batch.

Why is KE25012 significant?

KE25012 is also the number of a genuine Abhayrab batch manufactured by IIL. According to the company, the genuine batch was tested and released by the CDL under batch-release certificate CDL/2025/8392, dated November 7, 2025. It comprised 83,370 vials, which IIL says were distributed through its authorised supply network.

 

The company has also said it received no market complaints relating to the genuine batch and that no part of it was exported to another country.

Not the first counterfeit Abhayrab episode

The current investigation follows a separate counterfeit Abhayrab episode involving batch KA24014, which Indian authorities identified in January 2025.

 

The earlier case prompted warnings for travellers who may have received the counterfeit vaccine in India. Australia's Australian Technical Advisory Group on Immunisation (ATAGI) issued guidance in January 2026 advising potentially affected people to seek medical advice about replacement vaccination.

 

Australian health authorities also said, in December 2025, the counterfeit product differed from the genuine vaccine in formulation, packaging and labelling and could mean affected people were not adequately protected against rabies.

 

The scale of Abhayrab's presence in the market also raises the stakes. IIL estimates that the vaccine accounts for about 40 per cent of India's rabies vaccine market. According to company information, Abhayrab has been supplied to more than 40 countries.

What has the regulator done?

On August 27, Drugs Controller General of India Rajeev Singh Raghuvanshi asked state drug regulators to maintain strict vigilance over the movement, distribution and availability of Abhayrab bearing batch number KE25012.

 

The CDSCO's September 5 public notice subsequently alerted states and Union territories.

 

Four people have been arrested in connection with the wider Delhi investigation, and the probe is continuing.

 

What remains unclear is how many suspect vials, if any, reached patients before the seizure. Reuters reported that the government document did not quantify the amount of fake vaccine that may have entered circulation.