Brian Werth

Associate Professor

Department of Pharmacy, Pharmacy Faculty, School Faculty

Telephone: (206) 685-2302


Office Location: H-361-E

Website: PubMed


  • PharmD, University of New Mexico

Research Interests

  • Mechanisms of resistance to antibiotics
  • Antimicrobial pharmacodynamics
  • Antimicrobial resistance, cross-resistance, and synergy
  • Staphylococcal infections

Courses Taught

  • PHRMCY 533: Pharmacotherapeutics III; disorders of the cardiovascular, pulmonary, renal, and endocrine systems


Dr. Werth received his PharmD from the University of New Mexico before completing a pharmacy practice residency at The Queen’s Medical Center in Honolulu, HI. He then completed an Infectious Diseases Pharmacotherapy Fellowship at Wayne State University in Detroit, MI before joining the University of Washington Department of Pharmacy as an Assistant Professor in 2013.

Dr. Werth’s research interest is in antimicrobial resistance and the pharmacokinetics and pharmacodynamics of antimicrobials. His interdisciplinary translational research program is primarily focused on understanding the mechanisms of cross-resistance among glycopeptides, lipopeptides, and lipoglycopeptides in Methicillin-Resistant Staphylococcus aureus (MRSA).


Selected Publications

  • Zhang R, Barreras Beltran IA, Ashford NK, Penewit K, Waalkes A, Holmes EA, Hines KM, Salipante SJ, Xu L, Werth BJ. Synergy Between Beta-Lactams and Lipo-, Glyco-, and Lipoglycopeptides, Is Independent of the Seesaw Effect in Methicillin-Resistant Staphylococcus aureus. Front Mol Biosci. 2021 Sep 9;8:688357. doi: 10.3389/fmolb.2021.688357. PMID: 34646861; PMCID: PMC8503943.
  • Shen T, Hines KM, Ashford NK, Werth BJ, Xu L. Varied Contribution of Phospholipid Shedding From Membrane to Daptomycin Tolerance in Staphylococcus aureus. Front Mol Biosci. 2021 Jun 11;8:679949. doi: 10.3389/fmolb.2021.679949. PMID: 34179085; PMCID: PMC8226217.
  • Seni J, Mapunjo SG, Wittenauer R, Valimba R, Stergachis A, Werth BJ, Saitoti S, Mhadu NH, Lusaya E, Konduri N. Antimicrobial use across six referral hospitals in Tanzania: a point prevalence survey. BMJ Open. 2020 Dec 15;10(12):e042819. doi: 10.1136/bmjopen-2020-042819. PMID: 33323448; PMCID: PMC7745526.
  • Mbwasi R, Mapunjo S, Wittenauer R, Valimba R, Msovela K, Werth BJ, Khea AM, Nkiligi EA, Lusaya E, Stergachis A, Konduri N. National Consumption of Antimicrobials in Tanzania: 2017-2019. Front Pharmacol. 2020 Oct 30;11:585553. doi: 10.3389/fphar.2020.585553. PMID: 33192526; PMCID: PMC7662556.
  • Shen T, Penewit K, Waalkes A, Xu L, Salipante SJ, Nath A, Werth BJ. Identification of a novel tedizolid resistance mutation in rpoB of MRSA after in vitro serial passage. J Antimicrob Chemother. 2021 Jan 19;76(2):292-296. doi: 10.1093/jac/dkaa422. PMID: 33057715; PMCID: PMC8600019.
  • Werth BJ, Ashford NK, Penewit K, Waalkes A, Holmes EA, Ross DH, Shen T, Hines KM, Salipante SJ, Xu L. Dalbavancin exposure in vitro selects for dalbavancin-non-susceptible and vancomycin-intermediate strains of methicillin-resistant Staphylococcus aureus. Clin Microbiol Infect. 2021 Jun;27(6):910.e1-910.e8. doi: 10.1016/j.cmi.2020.08.025. Epub 2020 Aug 28. PMID: 32866650; PMCID: PMC7914275.
  • Theuretzbacher U, Barbee L, Connolly K, Drusano G, Fernandes P, Hook E, Jerse A, O’Donnell J, Unemo M, Van Bambeke F, VanScoy B, Warn P, Werth BJ, Franceschi F, Alirol E. Pharmacokinetic/pharmacodynamic considerations for new and current therapeutic drugs for uncomplicated gonorrhoea-challenges and opportunities. Clin Microbiol Infect. 2020 Dec;26(12):1630-1635. doi: 10.1016/j.cmi.2020.08.006. Epub 2020 Aug 13. PMID: 32798687.
  • Barbee LA, Dombrowski JC, Hermann S, Werth BJ, Ramchandani M, Ocbamichael N, Barash E, Golden MR. “Sex in the Time of COVID”: Clinical Guidelines for Sexually Transmitted Disease Management in an Era of Social Distancing. Sex Transm Dis. 2020 Jul;47(7):427-430. doi: 10.1097/OLQ.0000000000001194. PMID: 32541302; PMCID: PMC7448723.
  • Hines KM, Shen T, Ashford NK, Waalkes A, Penewit K, Holmes EA, McLean K, Salipante SJ, Werth BJ, Xu L. Occurrence of cross-resistance and β-lactam seesaw effect in glycopeptide-, lipopeptide- and lipoglycopeptide-resistant MRSA correlates with membrane phosphatidylglycerol levels. J Antimicrob Chemother. 2020 May 1;75(5):1182-1186. doi: 10.1093/jac/dkz562. PMID: 32016379; PMCID: PMC7869793.
  • Barbee LA, Soge OO, Morgan J, Leclair A, Bass T, Werth BJ, Hughes JP, Golden MR. Gentamicin Alone Is Inadequate to Eradicate Neisseria Gonorrhoea From the Pharynx. Clin Infect Dis. 2020 Nov 5;71(8):1877-1882. doi: 10.1093/cid/ciz1109. PMID: 31712813; PMCID: PMC7755014.
  • Hines KM, Waalkes A, Penewit K, Holmes EA, Salipante SJ, Werth BJ, Xu L. Characterization of the Mechanisms of Daptomycin Resistance among Gram-Positive Bacterial Pathogens by Multidimensional Lipidomics. mSphere. 2017 Dec 13. PMID 29242835.
  • Werth BJ, Jain R, Hahn A, Cummings L, Weaver T, Waalkes A, Sengupta D, Salipante SJ, Rakita RM, Butler-Wu SM. Emergence of dalbavancin non-susceptible, vancomycin-intermediate Staphylococcus aureus (VISA) after treatment of MRSA central line-associated bloodstream infection with a dalbavancin- and vancomycin-containing regimen. Clin Microbiol Infect. 2017 Aug 3. PMID 28782651
  • Werth BJ, Shireman LM. Pharmacodynamics of ceftaroline plus ampicillin Against Enterococcus faecalis in an in vitro pharmacokinetic/pharmacodynamic model of simulated endocardial vegetations. Antimicrob Agents Chemother. 2017 Jan 17. PMID 28096164.
  • Werth BJ. Exploring the pharmacodynamic interactions between tedizolid and other orally bioavailable antimicrobials against Staphylococcus aureus and Staphylococcus epidermidis. J Antimicrob Chemother. 2017 Jan 31. PMID 28158617
  • Hahn WO, Werth BJ, Butler-Wu SM, Rakita RM. Corynebacterium striatum: a multidrug resistant pathogen associated with increased parenteral antibiotic usage. Emerg Infect Dis. 2016 Nov 22. PMID 27767926
  • Werth BJ, Smith JR, Sakoulas G. New Guidelines Endorse Old Recommendations for Invasive Enterococcal Infections. Clin Infect Dis. 2016 May 8. PMID 27161781
  • Mather CA, Werth BJ, Sivagnanam S, SenGupta DJ, Butler-Wu SM. Rapid Detection of Vancomycin Intermediate Staphylococcus aureus (VISA) by Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). J Clin Microbiol. 2016 Jan 13. PMID 26763961
  • Werth BJ, Hahn W, Butler-Wu SM, Rakita RM. Emergence of high-level daptomycin resistance in Corynebacterium striatum in two patients with left ventricular assist device infections” Microbial Drug Resistance. 2015 Nov 6 PMID 26544621
  • Sakoulas G, Kumaraswamy M, Nonejuie P, Werth BJ, Rybak MJ, Pogliano J, Rice LB, Nizet V. Differential Effects of Penicillin Binding Protein Inactivation on the Susceptibility of Enterococcus faecium to Daptomycin and Human Cathelicidin LL-37. Antimicrob Agents Chemother. 2015 July 20. PMID 26195528
  • Werth BJ, Abbott AN. The combination of ampicillin plus ceftaroline is synergistic against Enterococcus faecalis. J Antimicrob Chemother. 2015 May 7. PMID 25953804.
  • Werth BJ, Carreno JJ, Reveles KR. Shifting trends in the incidence of Pseudomonas aeruginosa septicemia in hospitalized adults in the united states from 1996-2010. Am J Infect Control. 2015 Mar 14. PMID: 25783865