Kenneth W. Witwer is an associate professor of molecular and comparative pathobiology and neurology at the Johns Hopkins University School of Medicine in Baltimore, Maryland, United States.

Witwer is the managing editor of the journal Cytotherapy and a member of the Richman Family Precision Medicine Center of Excellence in Alzheimer's Disease.

[5][6] Beginning in 2013, Witwer examined the hypothesis that RNAs such as miRNAs in dietary substances could regulate endogenous genes in mammals.

[14] Witwer is an associate editor of the Journal of Extracellular Vesicles and a member of the editorial boards of Clinical Chemistry and AIDS.

He was corresponding author in 2013 of the first position paper of the International Society for Extracellular Vesicles, on standardization of isolation and characterization of EVs in RNA studies.

[17] With Clotilde Théry, he coordinated the Minimal Information for Studies of Extracellular Vesicles (MISEV2018), a consensus guidelines document for the EV field.