India flags Abhayrab rabies vaccine batch as substandard, probes if spurious: Document

Highlights:

• India flags potentially spurious batch of Abhayrab vaccine
• IIL said examined vials were not made by company, asked regulator to probe issue
• Regulator said no part of batch had been exported, 4 people were arrested
• Alert comes months after global warnings on counterfeit doses
• Rabies vaccine batch fails potency test, prompting probe

India's drug regulator has flagged a batch of widely used rabies vaccine Abhayrab as substandard and potentially spurious after it failed a potency test, a government document seen by Reuters shows.

The finding marks the second time in less than two years that concerns have been raised about counterfeit Abhayrab doses in India, a country that reports nearly 6,000 rabies deaths a year and where the vaccine is a frontline defence against the otherwise nearly always fatal infection.

Indian Immunologicals Ltd, which makes Abhayrab and holds a 40% share of the domestic rabies vaccine market, said on Saturday in a statement dated 4 September that the vials carrying the label Abhayrab that were examined by the regulator were not manufactured by the company.

"The CDSCO drew vaccine samples from an unlicensed residential premises located at Mukherjee Nagar, Delhi", Sunil Tiwari, VP of IIL, said.

The vials were labelled as Abhayrab batch number KE25012, he added.

In a statement on Saturday, the federal drug regulator said no part of batch KE25012 had been exported to any other country, adding that four people had been arrested by Delhi Police in connection with the case.

The regulator also confirmed that the batch under investigation was seized from an unlicensed premises.

IIL said it had provided batch records to the regulator and asked authorities to trace the source of the vials and act against those responsible, while cooperating with the investigation.

In an 27 August letter to state drug regulators, India's Drugs Controller General Rajeev Singh Raghuvanshi asked officials to maintain "strict vigilance" over the movement and distribution of Abhayrab batch KE25012 and take regulatory action, as necessary.

The action came after the government's Central Drugs Laboratory in Kasauli found that a field sample of the vaccine did not meet potency requirements and classified it as "not of standard quality" and a "misbranded" drug, according to the government document.

IIL said it had received queries from healthcare professionals regarding batch KE25012 but no market complaints. It added that the original batch consisted of 83,370 vials distributed through authorised channels.

IIL added that every batch of Abhayrab undergoes independent government testing before release and that vaccines supplied through authorised channels, including hospitals and licensed pharmacies, were unaffected by the issue.

While the sample passed sterility, moisture and identity tests, the laboratory also found significant differences between the sampled product and a retained reference sample of the same vaccine previously submitted by a division of Indian Immunologicals for regulatory testing.

These included discrepancies in labelling, artwork, QR code verification, cap colour, licence details and packaging text.

The regulator said the findings raised concerns about the sample's "identity and authenticity" and warranted investigation into whether it could be a spurious drug under India's Drugs and Cosmetics Act.

Having supplied more than 210 million doses of Abhayrab in India and other countries for over two decades, IIL said the lab report identified 17 differences between the seized samples and the retention samples of the same batch held at the lab.

Previous warnings to travellers

Indian Immunologicals had previously notified India's drug regulator in January 2025 that counterfeit Abhayrab doses bearing batch number KA24014 had entered the market. Global health authorities in the US, Britain and Australia later issued alerts for travellers who may have received the vaccine in India.

At the time, the company said it had not manufactured the counterfeit batch, reiterated that the incident was isolated and said it was not aware of any other counterfeit doses in circulation.

India records an estimated 5,726 human rabies deaths annually, according to a 2024 study by the Indian Council of Medical Research's National Institute of Epidemiology.

Abhayrab is a human rabies vaccine used for both pre- and post-exposure protection against rabies. It is administered in multiple doses and is also supplied to government immunisation programmes in India.

The government document does not state how many doses of the batch now being investigated may have been distributed, nor whether any doses from the flagged batch had been exported or whether foreign regulators had been notified of the latest alert.

Indian Immunologicals exports Abhayrab to more than 40 countries including South Africa, Turkey, Vietnam, Cambodia, Zimbabwe, Thailand and the United Arab Emirates.