Clinical research (research involving human subjects) may include the evaluation of therapies, treatments, devices, medications, surgeries, and/or diagnostic tools. The results from clinical research advance the efficacy and safety of new treatments and directly improve patient care and quality of life.

The Division of Infectious Diseases has a research team whom coordinates all clinical research with the Infectious Diseases clinical faculty. In addition to clinical research, the faculty members conduct laboratory research both at the UC Davis Medical Center and on the UC Davis Campus

Each type of clinical research plays an integral part in strengthening our knowledge of certain diseases or conditions. With clinical research, we can implement better techniques to diagnose, treat, and prevent human diseases and conditions.


Clinical Trials

The majority of clinical research consists of clinical trials, which may be sponsored or funded by physicians, foundations, federal health agencies (such as the National Institutes of Health), pharmaceutical companies, or university grants. A clinical trial is a study that looks for new ways to prevent, detect, diagnose, and/or treat a disease or condition. Clinical trials are research projects that have two main objectives in mind: patient safety and disease treatment/prevention. Patients are at the forefront of medicine when they choose to be a participant in a clinical trial. Not only are they contributing to the medical and scientific understanding of their disease, but they also have access to the newest treatments.


There are different phases of clinical trials. Although each phase has a different purpose, each phase also focuses on evaluating the safety of the treatment being tested. 

  • Phase I trials test the treatment for the first time to make sure it is safe and evaluate any side effects
  • Phase II trials test a treatment to see how effective it is
  • Phase III trials test a treatment to compare it to standard treatments
  • Phase IV trials are when the treatment is already approved by the FDA, but researchers are still following the treatment to ensure safety and  to measure its benefits 

After a Phase I or Phase II trial, the researchers decide whether they want to move to the next phase or to stop testing the treatment. When a Phase III trial is completed, researchers analyze the data and determine their medical significance. Results from clinical trials are often published in scientific journals.

Clinical research studies are very different from regular medical care. Your primary care physician will diagnose and treat you for an illness or condition. Clinical researchers gather new information to help improve future medical care.

For additional information, contact the research team.


Clostridium difficile Infection

Study Title: A multi-center, randomized, double-blind study to compare the efficacy and safety of cadazolid versus vancomycin in subjects with Clostridium difficile-associated diarrhea (CDAD) 

Study Type: Phase III 

  • Purpose: The goal of this trial is to determine if 10 days of orally administered cadazolid is non-inferior to orally administered vancomycin in subjects with CDAD.
  • Principal Investigator: Stuart Cohen, M.D.
  • Study Contacts:

Study Title: An Open Label Efficacy and Safety Assessment of Rebiotix RBX2660 (microbiota suspension) for the Treatment of Recurrent Clostridium difficile Infection

Study Type: Phase IIb

  • Purpose: The goal of this trial is to evaluate the efficacy and safety of RBX2660 for the treatment of recurrent CDI.
  • Principal Investigator: Stuart Cohen, M.D.
  • Study Contacts:



Study Title: A Phase III, Randomized, Double-Blind, Active Comparator-Controlled Clinical Trial to Study the Safety, Tolerability, and Efficacy of Imipenem/Cilastatin/Relebactam (MK-7655A) Versus Piperacillin/Tazobactam in Subjects with Hospital-Acquired Bacterial Pneumonia or Ventilator-Associated Bacterial Pneumonia

Study Type: Phase III 

  • Purpose: The primary objective of this study is to compare the incidence rate of all-cause mortality of IMI/REL to PIP/TAZ in subjects diagnosed with HABP/VABP (Hospital-Acquired Bacterial Pneumonia/Ventilator-Associated Bacterial Pneumonia).
  • Principal Investigator: Hien Nguyen, M.D.
  • Study Contacts:

Study Title: A prospective, Randomized, Double-Blind, Multicenter, Phase 3 Study to Assess the Safety and Efficacy of Intravenous Ceftolozane/Tazobactam Compared with Meropenem in Adult Patients with Ventilated Nosocomial Pneumonia

Study Type: Phase III

  • Purpose: The primary objective of this study is to demonstrate the non-inferiority of ceftolozane/tazobactam versus meropenem in adult subjects with ventilated nosocomial pneumonia
  • Principal Investigator: Hien Nguyen, M.D.
  • Study Contacts:


Fungal Infections

Study Title: A Multicenter, Case Control Study of a Lateral Flow Assay and Enzyme Immunoassay for Diagnosis of Histoplasmosis

Study Type: N/A: Diagnostic tool comparison

  • Purpose: This research study will look at how well two laboratory tests work in detecting fungal infections, which are present in all types of fungus.
  • Principal Investigator: George Thompson, M.D.
  • Study Contacts: 


Skin and Skin Structure Infections

Study Title: Telavancin Observational Use Registry (TOUR)

Study Type: Observational

  • Purpose: The objectives of the study are to characterize the patterns of telavancin usage by: characteristics of patients who receive telavancin, identify prescribing patterns, describe clinical effectiveness, and to describe safety information.
  • Principal Investigator: Hien Nguyen, M.D.
  • Study Contacts:



Center for Comparative Medicine
Clinical and Translational Science Center
California National Primate Research Center
Department of Medical Microbiology and Immunology
Institute for Regenerative Cures
Center for Biophotonics
Center for Vectorborne Diseases