About

Kelly Reynolds MSPH, PhD is a Professor and Chair of the Department of Community, Environment and Policy at the University of Arizona, where she also serves as the Director of the Environment, Exposure Science and Risk Assessment Center (ESRAC). Since 1990, Dr. Reynolds has worked as a researcher and public health educator specializing in environmental science, with a focus on water quality, food safety, and disease transmission. Her extensive research includes projects on detecting human viruses in drinking water using laser technology, assessing risks associated with tap water, and monitoring bacteria such as MRSA in home environments. She has contributed to understanding waterborne pathogens and their impact on public health, with her work aiming to develop methods to identify hazards and inform public participation in reducing exposure. Dr. Reynolds holds a PhD in Agriculture and Life Sciences from the University of Arizona and a master's degree in Public Health from the University of South Florida. She has published numerous journal articles and book chapters, and her research continues to advance the detection and mitigation of environmental health risks.

Research topics

• Medicine
• Virology
• Biology
• Environmental health
• Engineering
• Chemistry
• Internal medicine
• Chromatography
• Intensive care medicine
• Family medicine
• Waste management
• Emergency medicine
• Optics
• Biotechnology
• Psychology
• Engineering ethics
• Physics
• Surgery
• Microbiology
• Dentistry

Selected publications

• Clinical Pharmacology Guidances Advancing Drug Development and Regulatory Assessment: Role and Opportunities

  The Journal of Clinical Pharmacology · 2025-04-16

  articleOpen access

  Clear and pragmatic scientific recommendations from regulators promote consistent and timely generation of quality data during drug development leading to more efficient regulatory review. To provide these scientific recommendations, the Office of Clinical Pharmacology (OCP) within the US Food and Drug Administration (FDA) has adopted a lifecycle approach to guidance and policy development.1 This end-to-end process provides a structured approach for identification, development, clearance, implementation, and evaluation of guidances and policies, and facilitates modernization of existing guidances and policies or development of de novo guidances and policies in an informed manner in an ever-changing scientific landscape (Figure 1). In the multidisciplinary field of clinical pharmacology, such an approach is important to ensure that guidances and policies are relevant, contemporary, and informed by accumulated scientific and regulatory experience. The goals are to enable innovation in drug development, ensure consistency in decision-making, and protect health and safety of real-world patients and research participants. Developing and updating clinical pharmacology guidances benefits from proactive engagement of all the interested parties within the ecosystem of drug development, regulatory assessment, and patient care. As part of engagement efforts, OCP published a federal register notice and conducted a public workshop to identify emerging scientific topics that might benefit from further scientific research and best practice development.2, 3 Herein, we highlight the discussions from the “Clinical Pharmacology Guidances Advancing Drug Development and Regulatory Assessment: Role and Opportunities” workshop conducted as part of a collaboration between OCP and the University of Maryland Center for Excellence in Regulatory Science and Innovation (MCERSI) on May 8–9, 2024. The discussions focused on five areas: specific patient populations, rare diseases, drug lifecycle management, application of quantitative approaches, and value of globally harmonized clinical pharmacology guidelines. The workshop highlighted current guidances relevant to the field of clinical pharmacology, discussed the challenges and gaps in applying clinical pharmacology principles during drug development, and identified potential opportunities for further regulatory research and best practice development. Outlined below and in Figure 2 are some of the challenges and opportunities identified by the discussants. “Specific patient populations” typically refers to subgroups of patients who may require additional considerations to optimize therapy based on potential differences in drug disposition or response, and may include subpopulations such as older adults, children, those with organ impairment, and pregnant or lactating females. While several regulatory guidances are dedicated to generating data and prescribing recommendations for some specific populations, dedicated guidances are not available for all subpopulations for which there may be differences in exposure or response based on specific intrinsic or extrinsic factors.4-7 Additionally, some specific patient populations are more routinely included and evaluated in the drug development program and labeling (e.g., renal or hepatic impairment) compared to other populations (e.g., patients with comorbidities). Even within specific patient populations that are more frequently evaluated, data may still be scarce for some subgroups of these specific populations (e.g., patients with severe hepatic or severe renal impairment or end stage renal disease).8 In addition, an individual can have multiple conditions or comorbidities that result in (patho)physiological changes (e.g., older adult with reduced renal function and comorbid diseases taking multiple drugs), but generally studies and product labeling address the impact of only one factor at a time (e.g., age or drug–drug interaction). Discussions highlighted the need to use quantitative approaches rooted in mechanistic understanding to inform the drug development program (e.g., identify eligibility criteria for clinical trials and identify the need for standalone studies) and promote therapeutic optimization and individualization for a broader range of specific patient populations. Some challenges associated with rare disease drug development include small patient population size, limited understanding of natural history, suboptimal dose exploration, lack of validated endpoints or established biomarkers, and ability to meaningfully integrate patient and caregiver input. Several guidances are available to support rare disease drug development that attempt to address some of these challenges.9 However, opportunities to support patient-centric drug development remain, including proactive partnerships with patients and caregivers and utilization of innovative and patient-friendly trial designs such as those incorporating decentralized elements. Opportunities for clinical pharmacology investigations include informing the development of relevant disease-specific outcome measures, developing translational models of drug disposition and response, guiding drug use in certain subpopulations not studied in clinical trials, and integrating comprehensive biomarker approaches utilizing validated analytical methods. It is important to prospectively plan informative translational and clinical pharmacology studies to support dose optimization and evidence of effectiveness. In addition, novel therapeutic modalities (e.g., antisense oligonucleotides) that are targeted to specific rare diseases may require special consideration given their targeted mechanisms and pharmacological properties may be distinct from small molecules and biologics. Across the lifecycle of a drug, clinical pharmacology concepts are applied extensively to bridge new formulations, develop new dosage forms, change the route of administration, and extend the indication to new patient populations. Many clinical pharmacology guidances provide recommendations that become relevant over the lifecycle of a drug.10, 11 Additionally, bioequivalence, biopharmaceutic, and quality-related guidances are also important to demonstrate product performance control and consistency. Some challenges discussed were the multitude of changes that happen during the drug lifecycle and the lack of systematic knowledge management to share case examples. The opportunities identified included the need to increase patient-centric considerations throughout drug lifecycle, encourage multidisciplinary partnerships (e.g., clinical pharmacology, biopharmaceutics, chemists, and statisticians), and leverage modeling and simulation tools to address product and process changes. Over the past few decades, quantitative medicine approaches have been increasingly used to answer questions related to disease progression, dose finding, dose selection and optimization, study design, and evidence generation. Several existing guidances provide recommendations to facilitate the consistent utilization of the model informed drug development (MIDD) approaches by highlighting the foundational principles and applications.12-14 Challenges discussed focused on the need to take advantage of the rapid advances in methodologies and technologies and the need for the development of best practices that can foster broader acceptance of emerging technologies (e.g., artificial intelligence and machine learning) and use of real-world data. It was acknowledged that using the MIDD Paired Meeting Program to obtain real-time feedback during drug development and the Fit-for-Purpose Initiative to gain regulatory acceptance of drug development tools (DDTs) are some of the avenues for regulatory engagement on the development and application of quantitative medicine approaches. Clinical pharmacology guidances and policies provide a structure for drug development and also provide an opportunity to spur innovation on emerging topics. The discussants highlighted the need to strike a balance by not being overly prescriptive (i.e., allowing for the flexibility to adapt to the evolving science) while not being very high level (i.e., lacking meaningful and actionable recommendations). From conceptualization to final guidance publication, developing guidances is a resource intensive, repetitive, and lengthy process. Once published, guidances may be inconsistently implemented or be at risk of becoming obsolete if the tools, technologies, and approaches rapidly evolve. These challenges could be overcome by increased focus on education and regular evaluation of the effectiveness of final guidances. Additional suggestions to increase agility included publishing addendums to guidances (e.g., Q&A documents) and developing less prescriptive lean guidances that provide a framework for rapidly evolving topics. Globally harmonized guidelines that are developed via consensus among global regulators and stakeholders can help reduce uncertainty during global drug development. Many clinical pharmacology relevant guidelines have been published under the aegis of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), including the recent drug interaction guideline.15 Some of the challenges identified in developing harmonized guidelines include the time and resources needed to develop or update a harmonized guideline as well as anecdotal reports of inconsistent implementation of recommendations across global regulatory authorities. As with FDA guidances, a focus on education, training, and evaluation are needed to support successful implementation of global guidelines. Due to time and resource intensive nature, topic selection for future harmonization needs to balance impact with amenability to global alignment. The landscape of drug development is evolving, powered by advancing science as well as tools and technologies. In such an environment, guidances and policies must be nimble while ensuring consistency in decision-making. Cutting edge regulatory research and multistakeholder engagements are crucial to ensure that we can navigate the tension between consistency and innovation. Patient-centric regulatory research is valuable in filling knowledge gaps in drug discovery, development, regulation, and utilization, and can inform the scientific recommendations provided in guidances. However, to be effective, regulatory science should start at drug discovery and continue even after approval of the drug, with research adapting to identified knowledge gaps and needs. To ensure continuity, stakeholder input becomes crucial. Discussions with stakeholders from other government agencies, international regulators, industry, academia, professional societies, healthcare providers, patient advocates, and patients become important to learn about their experiences, challenges, and potential future opportunities. This can lead to the development of clear, pragmatic, contemporary, and patient-centered guidances and best practices that increase efficiency of the drug development process. The authors acknowledge the discussions from the presenters and panelists of the workshop titled “Clinical Pharmacology Guidances Advancing Drug Development and Regulatory Assessment: Role and Opportunities”: Issam Zineh, Peter Stein, Kathy Giacomini, Michelle Rohrer, Aarti Sawant, Sara Quinney, Michael Neely, Robert Schuck, Marshall Summar, Steven Ryder, Xinning Yang, Vikram Sinha, Paulo Paixão, Jenny Chien, Akihiro Ishiguro, Hao Zhu, Daniele Ouellet, Joga Gobburu, Karen Rowland Yeo, Ethan Stier, Roger Nosal, Xavier Pepin, and Kimberly Raines. The authors declare that they have no conflicts of interest to disclose. None. This manuscript reflects the views of the author and should not be construed to represent FDA's views or policies. No new data were generated for this manuscript.

  PublisherOA PDFDOI

• Quantifying fomite hotspots and targeted hygiene impacts in a hotel lobby

  International Journal of Hygiene and Environmental Health · 2025-04-29

  articleOpen accessSenior author

  reduction, p < 0.0001). The proportion of cross-contaminated surfaces (i.e., non-seeded sites testing positive) decreased from 13 % to 2 %, and the overall percentage of positive surfaces dropped from 50 % to 42 %. QMRA modeling demonstrated that infection risks from a single fomite-hand-face contact were highest for rhinovirus, rotavirus, and adenovirus. Following intervention, infection risk was reduced by over 97 % for all modeled pathogens. Risk levels for all viruses and bacteria met the U.S. EPA and WHO benchmark of less than 1 infection per 10,000 exposures used in drinking water guidelines. Notably, bacterial infection risks, already low pre-intervention, were further reduced to meet the more stringent 1 infection per 1,000,000 risk threshold. This is the first study to integrate real-world human behavior, viral tracer data, and QMRA modeling to assess Targeted Hygiene in a hospitality setting. Findings support the implementation of evidence-based hygiene protocols that prioritize high-risk surfaces and timing, offering a sustainable approach to reducing infection risks in public environments.

  PublisherDOI

• Quantifying Fomite Hotspots and Targeted Hygiene Impacts in a Hotel Lobby

  SSRN Electronic Journal · 2025-01-01

  preprintOpen access1st authorCorresponding
  PublisherDOI

• Unseen pathogen pathways: the impact of high-touch surfaces in public spaces

  Perspectives in Public Health · 2025-10-24 · 1 citations

  articleSenior author

  BACKGROUND: Surface contamination via hands plays an important role in pathogen spread in public spaces, particularly where numerous people interact with shared surfaces and objects. This study aimed to identify frequently touched surfaces, examine their interconnections, and evaluate the spread of a surrogate virus in a hotel lobby. METHODS: In a working hotel lobby (in Arizona, USA) a total of 30 h of observation were performed to identify the surfaces and objects touched by hotel users. The observed area included the lobby entrance, check-in desk and other communal areas. The sequence of touches performed by each observed individual was recorded, from which surface-to-surface interactions and fomite interconnections were determined. An entry doorknob and first floor elevator button were seeded with a bacteriophage (Phi X174) tracer; 4 h later, 25 surfaces were swabbed to determine tracer distribution and contamination levels. RESULTS: A total of 324 individuals performed 627 touches of 13 different fomites. The elevator button and front desk counter were the most frequently touched (32% and 22%, respectively). More than half (56%) touched 2 or more surfaces. Touches from the elevator button to other surfaces and from other surfaces to the elevator button made up 50% of all interactions.From two seeded sites, the tracer spread to 13 surfaces over 4 h. The most contaminated surfaces were tables, counter tops and door handles. CONCLUSIONS: The significant role of hands in transferring pathogens across frequently touched and highly interconnected surfaces in a hotel lobby was demonstrated through observations and sampling, highlighting the opportunity for hand and surface hygiene interventions to break the chain of infection in this hotel setting. These findings have implications for the optimisation of hygiene interventions in other hotel settings and are also applicable to similar public spaces, where common shared surfaces and objects (such as front desk counters and elevator buttons) could be targeted.

  PublisherDOI

• ICH M12 Drug Interaction Studies: Summary of the Efforts to Achieve Global Convergence

  Clinical Pharmacology & Therapeutics · 2025-03-19 · 12 citations

  reviewOpen access1st author

  The ICH M12 Guideline on Drug Interaction Studies is the result of a harmonization process led by global regulatory and industry experts with experience in drug-drug interaction (DDI) assessments and interpretation. The Expert Working Group (EWG) built on areas of regional consensus and identified solutions to topics lacking initial consensus. This article describes the topics addressed in the guideline, with emphasis on areas that required extensive discussion. It mentions topics that were the subject of comments during the public consultation period. The scope of the guideline is pharmacokinetic DDIs mediated by metabolic enzymes and drug transporters. It describes in vitro and clinical DDI studies and predictive modeling evaluations conducted during drug development. The understanding of DDI liability, in the context of the intended patient population, guides the development of risk management strategies. In the in vitro area, this article describes the considerations that support the use of experimentally measured fraction unbound for drugs with > 99% protein binding, modification of several in vitro criteria used to recommend a clinical DDI study and modification of DDI assessment for metabolites. Areas of close attention by the EWG for clinical evaluation included the use of endogenous biomarker studies, the use of nested DDI studies, and the establishment of no-effect boundaries. The article indicates the value of describing a general process for evaluating UGT-mediated DDIs, although specific criteria are not available. The guideline describes the current understanding of the role of predictive modeling in DDI evaluation. The topics described in this article can stimulate further growth in the science of DDI assessments.

  PublisherOA PDFDOI

• Corrigendum to “Quantitative microbial risk assessment (QMRA) tool for modelling pathogen infection risk to wastewater treatment plant workers” [Water Research volume 260 (2024) 121858]

  Water Research · 2025-02-19

  erratumOpen access
  PublisherDOI

• Removal, Kill, and Transfer of Bacteria from Hands by Antibacterial or Nonantibacterial Soaps After Handling Raw Poultry

  Journal of Food Protection · 2024-04-04 · 1 citations

  articleOpen accessSenior author

  Hand hygiene is broadly recognized as a critical intervention in reducing the spread of disease-causing pathogens in both professional and personal uses. In this study, the impact of antibacterial (AB) or nonantibacterial soaps on the removal and postwash transfer of E. coli following the handling of raw poultry was assessed. Baseline bacterial contamination ranged between 107 and 109 CFU per hand. Hands were washed for 30 s in 40°C ± 2°C tap water using 2 mL of AB soap (0.5% and 1.0% Chloroxylenol, 0.5% Benzalkonium Chloride, or 4.0% Chlorhexidine Gluconate), non-AB soap (cosmetic/plain soap), or water. Postwash, water, and non-AB soap had a mean 3.63 and 3.65 Log10 reduction of E. coli on hands. AB treatments had a mean 4.19–4.35 Log10 reduction. Rinse water had mean bacterial counts of 8.62 and 8.88 Log10 CFU/mL for non-AB soap and water and 5.37–6.90 Log10 CFU/mL for AB treatments. Bacterial transfer was assessed by following the test subject’s handling of a sterile polymer knife handle for 30 s postwash. E. coli transfer ranged from 263 to 903 CFU/handle for AB soaps and 1572 or 1709 CFU/handle for water and non-AB soap. Differences between AB and non-AB treatments were statistically significant (p < 0.0001) for hands and rinse water. Differences in transfer from hands to knife handle were not statistically significant (p = 0.139). Combined, these data highlight significant differences in the performance of AB soaps relative to non-AB soaps in a food handling environment-specific usage example and provide an unexplored assessment of the bactericidal vs. removal effects of AB vs. non-AB soaps on bacteria removed from the hands. These data reinforce the importance of hand hygiene, provide new details on the differences between AB vs. non-AB soaps, and highlight potential differences to inform food handling environment operators and public health personnel on how these products may impact food safety.

  PublisherDOI

• Wastewater-based effective reproduction number and prediction under the absence of shedding information

  Environment International · 2024-11-14 · 3 citations

  articleOpen accessSenior authorCorresponding

  • A new framework for estimating R e and predicting epidemic status was developed. • The framework requires only wastewater concentration and generation distribution. • The state-space model successfully reproduces data in multiple epidemic curves. • The necessary sampling frequency depends on the precision of detection methods. • The framework estimates R e for IAV and SARS-CoV-2 and predicts wastewater concentration in the near future. Estimating effective reproduction number ( R e ) and predicting disease incidences are essential to formulate effective strategies for disease control. Although recent studies developed models for inferring R e from wastewater-based data, they require information on shedding dynamics. Here, we proposed a framework of R e estimation and prediction without shedding information. The framework consists of a space-state model for smoothing wastewater-based data and a renewal equation modified for wastewater-based data. The applicability of the framework was tested with simulated data and real-world data on Influenza A virus (IAV) and SARS-CoV-2 concentration in wastewater in 2022/2023 season in the USA. We confirmed the state-space model effectively fits various simulated epidemic curves and real-world data. In simulations, we found wastewater-based R e ( R e ww ) closely aligns with instantaneous clinical R e when shedding dynamics are rapid. For more prolonged shedding, R e w w approximates a smoothed R e over time. We also observed the necessary sampling frequency to trace dynamics of wastewater concentration and R e ww accurately in the framework varies depending on the precision of detection methods, the epidemic status, the transmissibility of infectious diseases, and shedding dynamics. By applying our framework to real-world data, we found R e ww for SARS-CoV-2 showed similar trend and values to clinically-based R e . R e ww for IAV ranged from 0.66 to 1.52 with a clear peak in the winter season, which agrees with previously reported R e . We also succeeded in predicting wastewater concentration in a few weeks from available wastewater-based data. These results indicate that our framework potentially enables near real-time monitoring of approximated R e and prediction of infectious disease dynamics through wastewater surveillance, which limits the delay between infection and reporting. Our framework is useful especially for regions where reliable clinical surveillance is not available and notifiable surveillance is abolished, and can be expanded to multiple infectious diseases that have been detected from wastewater.

  PublisherDOI

• Wastewater-Based Estimation of Influenza a Virus Shedding Dynamics and Infection Cases Using the Presens Model

  SSRN Electronic Journal · 2024-01-01

  preprintOpen accessSenior author
  PublisherDOI

• Biaxial strain tuning of excitons in monolayer MoSe$_2$ by high-temperature physical vapor deposition

  arXiv (Cornell University) · 2024-08-28 · 1 citations

  preprintOpen access

  We present strain tuning of excitonic emission in monolayer MoSe$_2$ by using a high-temperature physical vapor deposition (PVD). The use of two amorphous substrates, Si$_{3}$N$_{4}$ and SiO$_{2}$, provides two setpoints to induce distinct amounts of \textit{biaxial} tensile strain determined by a thermal expansion mismatch between the monolayer and the substrate. The tuning rate of the $A$-exciton transition energy is found to be 103 meV/\% by photoluminescence (PL), which represents the highest value realized by biaxial strain in transition metal dichalcogenides. The biaxial nature of the tensile strain is confirmed by polarization-resolved second harmonic generation, which reveals unperturbed in-plane three-fold symmetry of the monolayer. Furthermore, a softening of $A_\mathrm{1g}$ out-of-plane lattice vibration is identified in the Raman spectroscopy, which is known to be insignificant for uniaxial strain. Concomitantly, PL mapping of our PVD monolayers demonstrates (i) larger strain occurs in the interior of the mono-domain islands compared to the edges and (ii) the absence of island-size dependence in the magnitude of induced strain. Our results demonstrate an effective path towards strain engineering of excitons by using growth substrates, which holds great promise as a building block for future optoelectronic applications.

  PublisherOA PDFDOI

Frequent coauthors

• Amanda M. Wilson

  University of Arizona

  44 shared

• Charles P. Gerba

  43 shared

• Jonathan D. Sexton

  26 shared

• Robert A. Canales

  George Washington University

  14 shared

• Marc P. Verhougstraete

  University of Arizona

  14 shared

• Ian L. Pepper

  University of Arizona

  11 shared

• Jeong‐Yeol Yoon

  University of Arizona

  10 shared

• Paloma I. Beamer

  University of Arizona

  10 shared

Education

• PhD, Soil and Water Science

  The University of Arizona

  1995