AstraZeneca has voluntarily withdrawn the "marketing authorization" of its Covid vaccine, sold as Covishield in India and Vaxzevria in Europe.

In a statement to IANS, an SII spokesperson said that with India achieving higher vaccination rates in 2021 and 2022, as well as the emergence of new mutans variant strains, the demand for previous vaccines has significantly reduced.

“As a result, with effect from December 2021, we have stopped manufacturing and supplying additional doses of Covishield,” the spokesperson said.

Serum Institute said they fully understand the ongoing concerns and "it is important to emphasize our commitment to transparency and safety".

The company said that from the beginning, "we have disclosed all rare to very rare side effects, including thrombosis with thrombocytopenia syndrome, in the packaging insert in 2021".

Thrombotic thrombocytopenic syndrome (TTS) is a rare side effect that can cause blood clots and low blood platelet counts in people, which has been linked to at least 8 deaths in the UK as well as hundreds of serious injuries.

SII stressed that despite the challenges faced during the global pandemic, vaccine safety remains paramount.

“Be it AstraZeneca's Vaxzervaria or our own Covishield, bot vaccines have been instrumental in saving millions of lives across the world.

"We commend the collaborative efforts of governments and ministries to facilitate a unified global response against the pandemic," Seru Institute said.

Meanwhile, the British-Swedish pharmaceutical multinational is also being sued by more than 50 alleged victims and grieving relatives in a High Court case in the UK.