'Blood Clot Side Effects' Janssen and AZ Move to Upgrade Vaccines

[Image source=AP Yonhap News]

[Asia Economy Reporter Cho Hyun-ui] Janssen and AstraZeneca (AZ), which confirmed blood clot side effects in their COVID-19 vaccines, have started upgrading their vaccines.

The Wall Street Journal (WSJ) reported on the 13th (local time), citing anonymous sources, that "Johnson & Johnson, Janssen's parent company, and AZ have each begun research with external experts to eliminate side effects from their vaccines," adding, "The research is currently in its early stages."

A Johnson & Johnson spokesperson stated, "We are conducting research and analysis together with medical experts and international health organizations," while AZ said, "We are conducting various studies on thrombosis, including early diagnosis and treatment methods, in collaboration with authorities and the scientific community."

Both Janssen and AZ vaccines were developed using viral vectors. Janssen uses a weakened flu virus as the viral vector, while AZ uses a modified chimpanzee cold virus.

Sources said there is a rosy outlook that AZ may identify the cause of side effects and begin eliminating them as early as next year. Experts expect the two companies to research ways to improve or modify the viral vectors.

However, concerns have been raised that finding technology to eliminate side effects from existing vaccines will not be easy. WSJ stated, "It is uncertain whether the vaccines can be upgraded or if eliminating side effects would be profitable for the pharmaceutical companies."

If Janssen or AZ identify the cause of side effects and change their drug manufacturing methods, they will need to reapply for usage approval in each country. WSJ noted, "Both companies' vaccines can be stored for several months in a regular refrigerator," and added, "If they succeed in eliminating blood clot side effects, their vaccines could be widely used, comparable to Pfizer or Moderna."

This content was produced with the assistance of AI translation services.