India flags Abhayrab rabies vaccine batch as substandard, probes possible counterfeiting

Drug regulator launches investigation after vaccine sample fails potency test

India’s drug regulator has flagged a batch of the widely used Abhayrab rabies vaccine as “not of standard quality” after a sample failed a potency test, raising concerns that the doses could be counterfeit, according to a government document reviewed by Reuters.

The development is the second reported case in less than two years involving suspected counterfeit Abhayrab doses in India, where rabies remains a major public-health concern.

Indian Immunologicals Ltd (IIL), the manufacturer of Abhayrab, said the vials examined by authorities were not produced by the company.

Manufacturer says seized vials were not genuine

The vials were labelled as batch KE25012, IIL vice president Sunil Tiwari said in a statement dated Sept. 4.

The Central Drugs Standard Control Organisation (CDSCO) collected samples from an unlicensed residential premises in Delhi’s Mukherjee Nagar area, according to IIL.

The company said it had supplied batch records to the regulator and asked authorities to investigate the source of the vials and take action against those responsible.

The CDSCO said no portion of the flagged batch had been exported to other countries. Four people have been arrested by Delhi Police in connection with the investigation, the regulator said.

Potency test triggers regulatory action

India’s Drugs Controller General, Rajeev Singh Raghuvanshi, instructed state drug regulators in an Aug. 27 letter to maintain strict surveillance over the distribution and movement of Abhayrab batch KE25012.

The action followed testing at the government’s Central Drugs Laboratory in Kasauli. A field sample failed to meet the required potency standards and was classified as “not of standard quality” and as a “misbranded” drug, the government document showed.

Although the sample passed tests for sterility, moisture and identity, laboratory checks found differences between the seized product and a retained reference sample of the same batch.

The discrepancies included packaging details, labelling, artwork, QR-code verification, cap colour, licence information and wording on the packaging.

The findings prompted authorities to investigate whether the product could constitute a spurious drug under India’s Drugs and Cosmetics Act.

IIL says authorised supplies remain unaffected

IIL said the original KE25012 batch comprised 83,370 vials that were distributed through authorised channels.

The company said it had received enquiries from healthcare professionals about the batch but had not received complaints from the market.

IIL also said every Abhayrab batch undergoes independent government testing before being released and that products supplied through licensed pharmacies, hospitals and other authorised channels were not affected by the latest investigation.

The company said it has supplied more than 210 million doses of Abhayrab in India and overseas over more than two decades.

According to IIL, the laboratory report identified 17 differences between the seized samples and the retained samples of the same batch.

Previous counterfeit vaccine alert

The latest case follows a warning issued by IIL in January 2025 over counterfeit Abhayrab doses carrying batch number KA24014.

Authorities in the United States, Britain and Australia subsequently warned travellers who may have received the vaccine in India.

At the time, IIL said it had not manufactured the counterfeit doses and described the incident as isolated.

Rabies vaccine widely used in India

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

Abhayrab is used for both pre-exposure and post-exposure protection against rabies. The vaccine is administered in multiple doses and is also used in government immunisation programmes.

The government document does not specify how many doses from the flagged batch may have entered circulation.

It also does not say whether any doses from the batch were exported or whether overseas regulators have been notified about the latest investigation.

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