About

Dr. Travis J. Carlson is a Clinical Assistant Professor in the Pharmacotherapy Division of the College of Pharmacy at The University of Texas at Austin. He is also an infectious diseases pharmacist caring for patients at University Hospital in San Antonio. Dr. Carlson received his Doctor of Pharmacy from Drake University and completed his PGY-1 Residency at Aurora St. Luke’s Medical Center in Milwaukee, Wisconsin. He further specialized with a two-year Infectious Diseases Fellowship at Baylor St. Luke’s Medical Center in Houston, Texas, in conjunction with the University of Houston College of Pharmacy. He is a Board-Certified Infectious Diseases Pharmacist (BCIDP). His research interests include antimicrobial stewardship, Clostridioides difficile infection, antimicrobial resistance, and medication disposal. Dr. Carlson has published over 20 peer-reviewed articles and actively contributes to professional organizations, serving as Chair of the Public Outreach Committee for the Society of Infectious Diseases Pharmacists (SIDP) and providing continuing education materials for the American Society of Health-System Pharmacists (ASHP) and the American College of Clinical Pharmacy (ACCP). He is passionate about teaching pharmacy students relevant infectious diseases pharmacotherapy, conducting innovative research, and serving the pharmacy profession.

Research topics

• Medicine
• Internal medicine
• Microbiology
• Pediatrics
• Surgery
• Biology
• Emergency medicine
• Family medicine
• Gastroenterology
• Demography

Selected publications

• P-1210. Real-World Efficacy and Safety of Meropenem-Vaborbactam in Patients with Moderate to Severe Renal Impairment

  Open Forum Infectious Diseases · 2026-01-01

  articleOpen access

  Abstract Background Meropenem-vaborbactam (MEV) is a novel β-lactam β-lactamase inhibitor combination approved in the United States for the treatment of complicated urinary tract infections caused by resistant organisms. Its spectrum includes carbapenem-resistant Enterobacterales and Pseudomonas aeruginosa. Limited data exist on the use of MEV in patients with reduced renal function. This study compared clinical characteristics and outcomes between patients with moderate to severe renal impairment and those with mild or no impairment.Table 1.Baseline, infection, and treatment characteristics.Table 2.Clinical outcomes. Methods This was a real-world, multicenter, retrospective cohort study conducted between 2017 and 2025 in adult patients who received MEV for ≥72 hours. Patients with KDOQI CKD stages 3-5 or GFR < 60 mL/min/1.73m2 or on chronic dialysis were assigned to the renal impairment (RI) group. All other patients were assigned to the non-impaired (NI) group. The primary outcome was clinical success, defined as resolution or improvement in signs of infection without recurrence. Secondary outcomes included 30-day all-cause mortality, 30-day microbiologic recurrence, 30-day hospital readmission, and occurrence of treatment-emergent adverse events. Results Seventy-two patients were included in the RI group and 151 patients were included in the NI group. The median baseline eGFR was 52.3 vs. 91.3 mL/min/1.73m2 in the RI and NI groups, respectively. Nearly half (47%) of patients in the RI group were receiving chronic dialysis. Clinical success was achieved in 76% of patients in the RI group compared to 79% in the NI group (p=0.60). Thirty-day all-cause mortality was 20.8% in the RI group vs. 23.8% the in the NI group (p=0.62). Thirty-day microbiological recurrence and hospital readmission rates were similar between the two groups. Adverse events were rare in both groups and similar in incidence (2.8% vs. 2.6% in the RI and NI groups, respectively [p=0.96]). Conclusion This study demonstrated the clinical outcomes of MEV when used in patients with moderate to severe renal impairment. Prospective randomized trials in this patient population are needed to validate these findings. Disclosures Kevin W. Garey, PharmD, MS, FIDSA, FASHP, Acurx: Grant/Research Support|Merck & Co.: Grant/Research Support|Paratek Pharmaceuticals: Grant/Research Support Wesley D. Kufel, Pharm.D., BCPS, BCIDP, Merck & Co.: Grant/Research Support|Shionogi, Inc: Grant/Research Support|Shionogi, Inc: Honoraria Tamara Krekel, PharmD, BCPS, BCIDP, AbbVie: Advisor/Consultant|AbbVie: Honoraria|Shionogi: Advisor/Consultant|Shionogi: Honoraria Taylor Morrisette, PharmD, MPH, AbbVie Inc: Advisor/Consultant|AbbVie Inc.: Grant/Research Support|Copeland, Stair Valz & Lovell: Expert Testimony|Infectious Diseases Special Edition: Honoraria|Stellus Rx: Grant/Research Support Travis J. Carlson, PharmD, BCIDP, Aimmune Therapeutics, Inc.: Speaker bureau Venugopalan Veena, PharmD, Merck: Grant/Research Support Vasilios Athans, PharmD, BCIDP, Astellas Pharma: Advisor/Consultant Kimberly C. Claeys, PharmD, PhD, bioMérieux: Advisor/Consultant|bioMérieux: Honoraria Michael J. Rybak, PharmD, PhD, MPH, Abbvie: Grant/Research Support|Innoviva: Grant/Research Support|Melina: Grant/Research Support|Merck: Grant/Research Support|Shionogi: Grant/Research Support

  PublisherDOI

• P-805. Duration of Intravenous Acyclovir in Adults and Children with Suspected Herpes Simplex Virus Encephalitis at an Institution with the BioFire FilmArray Meningitis/Encephalitis Panel

  Open Forum Infectious Diseases · 2026-01-01

  articleOpen accessSenior author

  Abstract Background Herpes simplex encephalitis (HSE) is a rare infection with a high mortality rate if left untreated. Polymerase chain reaction (PCR) testing of cerebrospinal fluid (CSF) is the diagnostic gold standard, but false negatives can occur. Clinical guidelines recommend a repeat lumbar puncture for additional CSF testing when suspicion for HSE remains high. However, confirmatory re-testing of initial CSF samples through third-party laboratories has been observed in clinical practice. This practice may prolong empiric intravenous acyclovir (IV ACV) therapy. Methods This single-center retrospective cohort study included patients admitted to University Health in San Antonio, Texas, between July 1, 2020 and November 30, 2025, who received IV ACV and had CSF tested using the BioFire FilmArray Meningitis/Encephalitis Panel (BioFire ME Panel). All HSV-positive patients were included. Due to cohort size, HSV-negative adult patients were randomly sampled to match the number of HSV-negative pediatric patients. The primary outcome was IV ACV duration in hours following the BioFire ME Panel result. Results Among 217 patients, 12 adults and 1 pediatric patients had an HSV-positive BioFire ME Panel result. The median (interquartile range) IV ACV duration after Biofire ME Panel result was 115.2 (65.5 – 210.7) hours for HSV-positive patients versus 18.1 (4.5 – 47.2) hours for HSV-negative patients (P = 0.0002). Confirmatory re-testing at a third-party laboratory was observed in 22/102 (21.6%) pediatric and 3/115 (2.6%) adult patients, but none of these tests were positive. In the pediatric only subgroup, patients with a negative Biofire ME Panel result who underwent third-party confirmatory testing received IV ACV for a median of 79.8 (36.2 - 137.0) hours after the initial result compared to 25.4 (7.8 - 51.2) hours in patients without confirmatory testing (P < 0.0001). Conclusion Third-party PCR re-testing did not identify any false-negative BioFire ME Panel results and was associated with prolonged IV ACV use. Diagnostic stewardship initiatives targeting BioFire ME Panel utilization could reduce unnecessary testing, excessive antiviral exposure, associated costs, and treatment risks. Disclosures Travis J. Carlson, PharmD, BCIDP, Aimmune Therapeutics, Inc.: Speaker bureau

  PublisherDOI

• The Health-Related Quality of Life Aspects of Clostridioides difficile Infection

  2026-03-06

  book-chapter1st authorCorresponding

  Clostridioides difficile infection (CDI) imposes a massive burden on individual patients and society as a whole. However, the consequences of CDI from the patient’s perspective, particularly those who do not experience recurrence, hospitalization, colectomy, or death, are not well understood. Historically, patient-reported outcomes (PROs) have been underutilized in the study of CDI, but the literature describing the health-related quality of life (HRQoL) aspects of CDI and its various prevention/treatment strategies have increased dramatically in the past decade. These efforts culminated in the development and validation of two CDI-specific measurement tools, which have been incorporated into several randomized placebo-controlled trials. This chapter aims to summarize the available HRQoL measurement tools and the published data on PROs among patients with CDI and recurrent CDI.

  PublisherDOI

• P-717. Serologic response to doxycycline versus penicillin for treatment of early or late stage syphilis

  Open Forum Infectious Diseases · 2026-01-01

  articleOpen accessSenior author

  Abstract Background With intermittent barriers to penicillin use for syphilis treatment, alternative treatment strategies are needed. Some literature supports doxycycline, but data are limited in certain subgroups, such as people living with human immunodeficiency virus (PLWHIV) and those with late stages of syphilis. Methods This was a single-center, retrospective cohort study that included adults with a positive syphilis screen between 7/1/2020-11/30/2024 who received either doxycycline or penicillin. Patients were excluded if they received suboptimal treatment, were pregnant or incarcerated, or did not have a follow-up rapid plasma reagent (RPR). The primary outcome was serologic response, defined as a four-fold or greater decrease in RPR from baseline to 12 months. Patients were stratified by antibiotic treatment and matched 1:1 by age, sex, race, HIV status, baseline RPR, and stage of syphilis using nearest-neighbor matching without replacement. All p-values were two-sided, and p < 0.05 was considered statistically significant. Results A total of 110 patients were included: 80 in the penicillin group and 30 in the doxycycline group. The majority of patients were male (77%), non-white (75%), and PLWHIV (70%) with a mean (standard deviation [SD]) age of 38 (±10) years. In the penicillin group, 58/80 (73%) patients achieved serologic response versus 24/30 (80%) patients in the doxycycline group (p = 0.42). The mean (SD) time to serologic response was similar between groups: 165 (±69) days in the penicillin group versus 183 (±79) days in the doxycycline group. After matching, 60 patients remained: 30 in each group. In the penicillin group, 23/30 (77%) patients achieved serologic response versus 24/30 (80%) patients in the doxycycline group (p = 0.75). The mean (SD) time to serologic response was similar between groups: 163 (±73) versus 183 (±79) days in the penicillin and doxycycline groups, respectively. Conclusion Patients with syphilis who were treated with doxycycline had a similar rate of serologic response when compared to patients treated with penicillin. These findings suggest that doxycycline can be utilized as an alternative therapy in many patients with syphilis, regardless of stage or HIV status. Disclosures Travis J. Carlson, PharmD, BCIDP, Aimmune Therapeutics, Inc.: Speaker bureau

  PublisherDOI

• P-1925. Comparison of Outcomes in Obese Versus Non-Obese Patients Receiving Fluconazole and/or Micafungin for the Treatment of Candidemia

  Open Forum Infectious Diseases · 2026-01-01

  articleOpen access

  Abstract Background Clinical practice guidelines recommend initial echinocandin therapy followed by oral azole step-down therapy for the treatment of candidemia. However, the pharmacokinetics of these medications can be altered by patient characteristics, such as obesity. The purpose of this study was to compare outcomes in obese versus non-obese patients with candidemia treated with fluconazole and/or micafungin. Methods This single-center, retrospective cohort study included adults with candidemia admitted from 1/1/20 - 12/1/24. Patients receiving < 48 hours of fluconazole and/or micafungin, those with resistance to both agents, or those not receiving antifungals within 24 hours of positive culture were excluded. Treatment failure, the primary composite outcome comprised of 14-day mortality, 14-day microbiologic failure, and 30-day candidemia recurrence, was compared between obese (BMI > 30 kg/m2) and non-obese patients. Secondary outcomes included hospital length of stay (LOS). Results Ninety-six patients were included, 34 (35%) obese and 62 (65%) non-obese. Eleven (32%) obese and 7 (11%) non-obese patients received micafungin doses > 100 mg/day (P = 0.01). Among patients receiving fluconazole (n = 48), the median (interquartile range, IQR) weight-normalized dose to minimum inhibitory concentration (MIC) ratio was 6.6 (3.9-10.8) and 9.7 (3.3-21.2) in obese versus non-obese patients, respectively (P = 0.62). Treatment failure occurred in 13 (38%) obese and 20 (32%) non-obese patients (P=0.56). The median (IQR) LOS was 23 days in obese patients and 22 days in non-obese patients (P = 0.96). Conclusion Obesity was not associated with treatment failure in this cohort of hospitalized patients with candidemia. Nearly one-third of obese patients received micafungin doses > 100 mg/day, and the weight-normalized fluconazole dose to MIC ratios did not significantly differ in obese versus non-obese patients. Depending on local epidemiologic factors, it may be prudent to consider higher doses of fluconazole and/or micafungin in obese patients with candidemia. Disclosures Travis J. Carlson, PharmD, BCIDP, Aimmune Therapeutics, Inc.: Speaker bureau

  PublisherDOI

• Antibiotic appropriateness among patients experiencing homelessness at an interprofessional student-run free clinic

  Antimicrobial Stewardship & Healthcare Epidemiology · 2026-01-01

  articleOpen accessSenior author

  Abstract Oral antibiotic prescribing was evaluated at a student-run free clinic serving patients experiencing homelessness. A retrospective review over a 30-month period showed 40.8% antibiotics were inappropriate and 32.7% lacked sufficient documentation for assessment. These findings revealed ambulatory stewardship gaps, underscoring the need for antimicrobial stewardship interventions in student-run free clinics.

  PublisherOA PDFDOI

• Faecal pharmacokinetics, microbiome, and bile acid changes in healthy subjects given intravenous followed by oral omadacycline; a Phase 1 clinical trial

  Journal of Antimicrobial Chemotherapy · 2025-08-12 · 1 citations

  articleOpen access

  BACKGROUND: There is an urgent need to develop new antimicrobials effective intravenously for Clostridioides difficile infection (CDI). Omadacycline is an aminomethylcycline tetracycline available orally and intravenously with potent in vitro activity against C. difficile and a low propensity to cause CDI. The purpose of this study was to assess the safety, faecal pharmacokinetics, microbiome and bile acid changes in healthy subjects given a course of intravenous omadacycline with oral omadacycline step down after 5 days. METHODS: This Phase 1, open-label study was conducted in healthy volunteers 18-40 years. Subjects received a 5-day course of omadacycline given intravenously followed by 5 days of oral omadacycline. Stool samples were analysed for omadacycline concentrations, gut microbiome changes and bile acid changes from baseline. RESULTS: Eight healthy volunteers aged 30 ± 4 years (50% Female) were recruited and all completed therapy. All subjects had detectable omadacycline stool concentrations after 48 hours of intravenous dosing and averaged 195 ± 97 µg/g (mean ± SD) by day 5. Omadacycline concentrations increased rapidly after the start of oral therapy on day 6 with average concentrations of 854 ± 404 µg/g of stool by day 10. Microbiome and bile acid evaluations showed preservation of key microbiome taxa that confer health benefit and preservation of bile acid homeostasis. CONCLUSION: Intravenous omadacycline followed by oral step-down administration in healthy adults achieved high faecal concentrations while preserving key bacterial species and bile acid homeostasis in the gut. These findings support Phase 2 studies directed towards the development of omadacycline as a CDI-targeted antibiotic.

  PublisherOA PDFDOI

• 435. Evaluation of Fecal Pharmacokinetics and Metagenomic Changes Following the Administration of Intravenous Omadacycline to Healthy Subjects

  Open Forum Infectious Diseases · 2025-01-29

  articleOpen access

  Abstract Background Omadacycline (OMC), an aminomethylcycline antibiotic, has potent in vitro activity against C. difficile (CD) and has been associated with a low propensity to cause CD infection when used to treat other infections. A recent phase 1 study of oral OMC demonstrated its protective gut microbiome profile, despite achieving high fecal concentrations, compared to oral vancomycin in healthy subjects. This study aimed to investigate the fecal pharmacokinetics and gut microbiome changes of intravenous (IV) OMC following its administration to healthy volunteers. Methods Healthy adults aged 18 to 40 years consented to receive a 10-day course of OMC: 200 mg of IV on day 1, followed by 100 mg once daily on days 2-5, then 300 mg orally once daily on days 6-10. Daily stool samples were collected and metagenomic analysis targeting 16S ribosomal RNA gene was performed using the Miseq platform (Illumina). Fecal concentrations of OMC were measured using liquid chromatography, mass-spectrometry assay. Results Eight healthy volunteers aged 30±4 years (male: 50%; body mass index: 27.1±4.3 kg/m2) were enrolled. By day 2, 87.5% (7/8) of stool samples had detectable OMC concentrations >40 mcg/g stool, increasing to >100 mcg/g stool by day 5. The maximum OMC concentrations were observed on day 10 (mean 853.5 mcg/g stool). Metagenomic analysis revealed preservation of the Bacteroidota phylum (+0.5±0.3%; p=0.06) and a non-significant increase of the Proteobacteria phylum (+0.9±0.6%; p=0.1). Significant increases were observed in the Actinobacteriota and Verrucomicrobiota phyla (+1.1±0.3%; p< 0.05 and +1.7±0.5%; p< 0.0001, respectively). These changes were driven by the Bifidobacteriaceae and Akkermansiaceae families, respectively. A significant decrease in the Bacillota phylum (-5.1±0.7%; p< 0.0001) was observed, primarily in the Lachnospiraceae, Ruminococcaceae, and Streptococcaceae families. Conclusion Intravenous OMC achieved high fecal concentrations that exceeds the minimum inhibitory concentration 90 of CD while preserving key bacterial species in the gut. Studies investigating changes in bile acids and short-chain fatty acids corresponding with these metagenomic changes are warranted. Disclosures Travis J. Carlson, PharmD, BCIDP, Aimmune Therapeutics, Inc.: Speakers Bureau John C. Williamson, PharmD, Armata Pharmaceuticals: Grant/Research Support|Blue Collar Vaccines and Therapeutics: Board Member|Blue Collar Vaccines and Therapeutics: Ownership Interest|Paratek Pharmaceuticals: Grant/Research Support|ST Pharm Co, Ltd: Grant/Research Support Anne J. Gonzales-Luna, PharmD, BCIDP, Ferring Pharmaceuticals: Advisor/Consultant|Innoviva Specialty Therapeutics: Advisor/Consultant|Merck and Co: Grant/Research Support|Paratek Pharmaceuticals: Grant/Research Support|Seres Therapeutics: Grant/Research Support Kevin W. Garey, MS;PharmD, Paratek Pharmaceuticals: Grant/Research Support

  PublisherDOI

• Real-World Applications of Imipenem-Cilastatin-Relebactam: Insights From a Multicenter Observational Cohort Study

  Open Forum Infectious Diseases · 2025-02-26 · 10 citations

  articleOpen access

  Abstract Background Multidrug-resistant (MDR) gram-negative infections are a substantial threat to patients and public health. Imipenem-cilastatin-relebactam (IMI/REL) is a β-lactam/β-lactamase inhibitor with expanded activity against MDR Pseudomonas aeruginosa and carbapenem-resistant Enterobacterales. This study aims to describe the patient characteristics, prescribing patterns, and clinical outcomes associated with IMI/REL. Methods This was a retrospective, multicenter, observational study of patients ≥18 years old who received IMI/REL for ≥48 hours for a suspected or confirmed gram-negative infection. The primary outcome was clinical success, defined as improvement or resolution of infection-related signs or symptoms while receiving IMI/REL and the absence of 30-day microbiologic failure. Multivariable logistic regression analysis was performed to identify independent predictors of clinical success. Results The study included 151 patients from 24 US medical centers. IMI/REL was predominantly prescribed for lower respiratory tract infections, accounting for 52.3% of cases. Most patients were infected with a carbapenem-nonsusceptible pathogen (85.4%); P aeruginosa was frequently targeted (72.2%). Clinical success was achieved in 70.2% of patients. Heart failure, receipt of antibiotics within the past 90 days, intensive care unit admission at time of index culture collection, and isolation of difficult-to-treat resistant P aeruginosa were independently associated with a reduced odds of clinical success. Adverse events were reported in 6.0% of patients, leading to discontinuation of IMI/REL in 3 instances. Conclusions This study provides a comprehensive analysis of the real-world effectiveness and safety of IMI/REL. Comparative studies and investigations of specific subgroups will further enhance our understanding of IMI/REL in treating MDR infections.

  PublisherOA PDFDOI

• Quantifying Antimicrobial Disposals at Six Community Pharmacies With Longitudinal Medication Disposal Programs: An Underappreciated Component of a One Health Approach to Antimicrobial Stewardship

  Open Forum Infectious Diseases · 2025-02-07 · 2 citations

  articleOpen accessSenior author

  Background: Unused, unwanted, and expired (UUE) medications, including antibiotics, pose a risk to our patients, their families, and our environment. A One Health approach to antimicrobial stewardship calls for stewards to recognize the interconnection between humans and our shared environment. The aims of this project were 2-fold: (1) to educate community members about the importance of responsible medication disposal and (2) to quantify the UUE medications returned to community pharmacies. Methods: Medication disposal programs were established at several community pharmacies in central North Carolina. Periodically, pharmacy school faculty and students visited the participating pharmacies to identify, quantify, and dispose of all UUE medication returns. Medications were deactivated using a Deterra Multi-purpose or Rx Destroyer All-purpose Disposal System and disposed of in accordance with product instructions and applicable laws and regulations. Results: Between November 2021 and May 2023, 6 community pharmacies maintained longitudinal medication disposal programs. In total, 144 084 UUE prescription medication tablets/capsules containing ∼19.3 kg of active pharmaceutical ingredient (API) were disposed of. Antimicrobials accounted for 2.6% of all tablets/capsules and nearly 1.3 kg (6.6%) of APIs. The most disposed antibiotics were doxycycline, amoxicillin, clindamycin, cephalexin, and ciprofloxacin. Conclusions: In this geographically limited study, nearly 1.3 kg of antimicrobial API was disposed of in a span of 1.5 years. Recognizing antimicrobial disposal as an important component of a One Health approach to antimicrobial stewardship, with the goal of expanding these efforts, may influence antimicrobial resistance in our environment.

  PublisherOA PDFDOI

Frequent coauthors

• Kevin W. Garey

  University of Houston

  31 shared

• Anne J Gonzales-Luna

  University of Houston

  29 shared

• Michael P. Veve

  Henry Ford Hospital

  15 shared

• Michael J. Rybak

  Wayne State University

  14 shared

• Susan L. Davis

  13 shared

• Faris S. Alnezary

  Taibah University

  12 shared

• Mohammad Jahangir Alam

  Uttara University

  10 shared

• Sara Alosaimy

  Wayne State University

  9 shared

Education

• PharmD

  Drake University

  2016

Awards & honors

• Chair of the Public Outreach Committee for the Society of In…