'Sympathy goes out to...': AstraZeneca reaffirms safety of Covishield, Vaxzevria vaccines amid blood clot concerns

Amid recent concerns over potential rare side effects of the AstraZeneca-Oxford COVID-19 vaccine, the pharmaceutical giant has reaffirmed its dedication to patient safety, while underscoring its overall safety profile.

An AstraZeneca spokesperson said, "We extend our sympathy to anyone who has lost loved ones or experienced health issues. Patient safety remains our top priority, and regulatory authorities have stringent standards to ensure the safe use of all medicines, including vaccines."

The move follows AstraZeneca's recent acknowledgment that its Covid vaccines, Covishield and Vaxzevria, ‘can, in very rare cases, cause Thrombosis Thrombocytopenia Syndrome (TTS)’.

However, the pharmaceutical company asserts that extensive clinical trial data and real-world evidence consistently demonstrate the vaccine's safety and efficacy. Regulatory agencies worldwide maintain that the benefits of vaccination outweigh the risks of such extremely rare side effects.

In 2023, the World Health Organization (WHO) reported that Thrombosis Thrombocytopenia Syndrome (TTS) emerged as a new adverse event following immunization with COVID-19 vaccines based on non-replicating adenovirus vectors.

WHO stated that TTS is a serious and life-threatening adverse event. It issued interim emergency guidance to raise awareness about TTS in the context of COVID-19 vaccination, and to assist healthcare providers in assessing and managing potential TTS cases.

AstraZeneca had partnered with the Serum Institute of India (SII), the world's largest vaccine manufacturer, to supply the vaccine to the Indian Government. The Serum Institute of India produced a COVID-19 vaccine named Covishield.

Thrombosis Thrombocytopenia Syndrome (TTS)

Thrombosis Thrombocytopenia Syndrome (TTS) is a rare but serious condition characterized by blood clot formation (thrombosis) and low levels of platelets in the blood (thrombocytopenia). It can be a rare side effect following vaccination, particularly with adenovirus vector-based COVID-19 vaccines. Symptoms may include severe headache, abdominal pain, leg swelling, and shortness of breath.