Researchers at Israel’s Beilinson Medical Center have found that twice as many organ transplant recipients developed antibodies after their 3rd anti-covid jab compared to their 2nd dose. There were also good results in the over-60s, of which over 750,000 have had their 3rd vaccination.

https://www.timesofisrael.com/3rd-covid-shot-highly-potent-in-israels-immunocompromised-early-study-shows/