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# FDA Develops Hepatitis A Immune Response Biomarker
- URL: https://www.fdaweb.com/fda-develops-hepatitis-a-immune-response-biomarker/
- Published: 2019-09-10T12:00:00.000Z
- Updated: 2026-09-15T01:49:00.000Z
- Author: David McFarland
- Tags: Biologics, #legacy-id-D5144969

FDA says agency scientists have developed a technique that enables them to determine whether immune system cells (dendritic cells) appear primed to trigger the production of antibodies against Factor VIII products used to treat hemophilia A. “The technique might enable scientists to use the presence of such primed dendritic cells as biomarkers for potential immune reactions that would block the therapeutic effects of FVIII,” an online [post](https://www.fda.gov/vaccines-blood-biologics/science-research-biologics/fda-identifies-biomarker-immune-response-fviii-products-used-treat-hemophilia?ref=fdaweb.com) says.

The post says the biomarker is important because the production of antibodies against protein drugs is a major safety and efficacy concern during both drug development and the agency’s subsequent regulation of such products. Strategies that identify individuals and groups of individuals at risk for producing antibodies against such drugs would mitigate this problem, it says.

A report on the research was [reported](http://www.bloodadvances.org/content/3/9/1429?sso-checked=true&ref=fdaweb.com) in *Blood Advances*.