Faculty Directory
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Vanessa McMahan
Vanessa McMahan, PhD, MS is a member of the faculty at the Harvard Pilgrim Health Care Institute and Harvard Medical School. She received her doctoral degree from the University of Washington.
Dr. McMahan’s research focuses on optimizing the delivery of pre-exposure prophylaxis (PrEP) to people who use substances. Currently, Dr. McMahan is leading a study investigating interest in and delivery preferences for long-acting PrEP among cisgender men who have sex with men and use methamphetamine. She is also evaluating video directly observed therapy plus contingency management to support oral PrEP adherence among people who use methamphetamine. She has been involved in PrEP research since 2005 when she coordinated the the landmark international iPrEX trial, which was the first study to demonstrate the efficacy of PrEP. In addition to her PrEP research, Dr. McMahan partners with harm reduction organizations to assess the impact of safer smoking supplies for drug consumption. She has volunteered with syringe services programs since 2000.