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# Lawmakers Urge FDA to Prioritize T Cell Covid Tests
- URL: https://www.fdaweb.com/lawmakers-urge-fda-to-prioritize-t-cell-covid-tests/
- Published: 2021-06-17T12:00:00.000Z
- Updated: 2026-09-14T17:03:46.000Z
- Author: David McFarland
- Tags: Devices, #legacy-id-D5149568

Several Republican members of Congress, who are part of the Doctors Caucus on the Hill, are urging FDA to prioritize tests measuring the presence of T cell-mediated immunity to Covid-19\. Tests measuring T cells could provide better detection of immunity in those naturally infected and could also be pivotal in tracking immunity after vaccination, the lawmakers say in a 6/16 letter to acting FDA commissioner **Janet Woodcock**. “While antigen and PCR tests are diagnostics for active infections, diagnostics for the immune system after viraemia are essential for tracking immune response via prior infection or vaccination, and will be of increasing utility as we transition to the closing phases of the Covid-19 pandemic,” they write.

The letter says that infection may not always produce measurable antibodies, and measuring T cell response would better detect patients who have been previously infected and have an adaptive immune response. “A test to measure the T cell response would give healthcare providers a tool to measure if a Covid-19 vaccine available under an emergency use authorization is appropriate for their patients,” the lawmakers say in the letter.

The lawmakers note that FDA previously acknowledged that it isn’t prioritizing T-cell tests because it is prioritizing applications for rapid diagnosis, point-of-care diagnostics and variant diagnostics. “While this may have been appropriate at the peak of the pandemic,” the letter says, “the mitigation efforts must shift from triage to long-term, to include measuring vaccine-induced immunity and natural immune response. We ask that you reevaluate these priorities to consider long-term mitigation of Covid-19.

The letter was signed by Senator **Roger Marshall** (R-KS), Senator **Rand Paul** (R-KY) and Reps. **Andy Harris** (R-MD), **Neal Dunn** (R-FL), **Ronny Jackson** (R-TX), and **Mariannette Miller-Meeks** (R-IA).