Are you maybe referring to Pfizer figures seen within this
https://www.bbc.co.uk/news/uk-57214596 or have I missed another study?
"The Pfizer vaccine was found to be 88% effective at stopping symptomatic disease from the Indian variant two weeks after the second dose, compared with 93% effectiveness against the Kent variant.
The AstraZeneca jab was 60% effective against the Indian variant, compared with 66% against the Kent variant.
Other data shows it takes longer to reach maximum effectiveness with the AstraZeneca vaccine, PHE said."