White House COVID-19 advisor Anthony Fauci on Sunday downplayed a recent study from a prominent medical research center that deemed the Pfizer vaccine more effective than the Moderna vaccine. The Mayo Clinic and Cambridge-based biotech company Nfrence, in a study released last week, found that both mRNA COVID-19 vaccines’ effectiveness dropped in the month of July. However, it noted that Moderna’s vaccine effectiveness was 76 percent, as compared with Pfizer’s 42 percent. “That study … is a pre-print study, it hasn’t been fully peer-reviewed,” Fauci said on CBS’s “Face the Nation” Sunday of the recent study’s finding. Fauci added, “I don’t doubt what they’re seeing, but there are a lot of confounding variables in there, about when one was started, the relative amount of people in that cohort who were Delta versus Alpha,” referring to the two COVID-19 variants. He didn’t elaborate. “Right now, if we get boosters … it’s clear …