Obesity & OverweightBARI-PKNCT07748273
Rosuvastatin and Losartan Pharmacokinetics After Bariatric Surgery
A study testing Rosuvastatin in people with Obesity & Overweight and Bariatric Surgery, run by Hospital das Clínicas de Ribeirão Preto at 1 site in Brazil.
Trial summary
This prospective, open-label, non-randomized pharmacokinetic study will evaluate how Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy affect systemic exposure to single oral test doses of rosuvastatin and losartan. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Obesity & Overweight, Bariatric Surgery, Pharmacokinetics After Oral Intake
- What is being tested?
- Rosuvastatin
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- 1 siteBrazil
- Study dates
- 2 Aug 2026to 15 May 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adults aged 18 to 65 years;
- Formal clinical indication for RYGB or sleeve gastrectomy after multidisciplinary assessment;
- Bariatric surgery scheduled and no previous bariatric procedure;
- Able to understand the study and provide written informed consent.
Who cannot join
- Moderate or severe hepatic impairment, liver enzymes greater than 3 times the upper limit of normal, or Child-Pugh class B or C.
- Estimated glomerular filtration rate below 30 mL/min/1.73 m².
- Concomitant use of drugs that substantially affect rosuvastatin pharmacokinetics and cannot be temporarily discontinued, including cyclosporine, gemfibrozil, or potent OATP1B1/BCRP or CYP2C9 inhibitors.
- Systemic antibiotic use within 3 months or probiotic, prebiotic, or synbiotic use within 4 weeks before sampling.
- Continuous current rosuvastatin or other statin therapy unless medically discontinued with an adequate washout period under physician supervision.
- Clinically relevant baseline hypotension, significant hyperkalemia, renal impairment, or another condition that makes a losartan test dose unsafe.
- Severe postoperative complication preventing oral dosing, including active gastrointestinal leak, intractable vomiting, or severe anastomotic stenosis.
- Pregnancy. Participants of childbearing potential undergo routine preoperative beta-hCG testing.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Brazil1 site
Hospital das Clínicas, Ribeirão Preto Medical School, University of São Paulo
Ribeirão Preto, São Paulo, 14048900
Fabiana CP Valera, MD PhD, +5516981548312, facpvalera@fmrp.usp.br
About this study
Official title: Comparative Evaluation of Rosuvastatin and Losartan Pharmacokinetics and the Associations Between Gut Microbiota Alterations and Changes in Systemic Drug Exposure in Patients Undergoing Roux-en-Y Gastric Bypass or Sleeve Gastrectomy
This prospective, open-label, non-randomized pharmacokinetic study will evaluate how Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy affect systemic exposure to single oral test doses of rosuvastatin and losartan. Sixty adults scheduled for bariatric surgery will enter one of two parallel groups according to the clinically selected operation (30 RYGB and 30 sleeve gastrectomy). Each participant will receive rosuvastatin 10 mg and losartan 25 mg once within 30 days before surgery and again approximately 12 weeks after surgery. Plasma samples collected before dosing and at 1.5 and 4 hours after dosing will be used with maximum a posteriori Bayesian estimation to estimate individual pharmacokinetic parameters. In the 30-participant RYGB group only, paired stool samples will be used to explore gut microbiota and untargeted fecal metabolomic changes. The primary objective is to compare within-participant changes and between-procedure differences in drug exposure after bariatric surgery.
Read the detailed description
Anatomical and physiological changes after bariatric surgery may alter oral drug absorption, first-pass metabolism, transporter activity, and systemic exposure. RYGB bypasses the duodenum and proximal jejunum, whereas sleeve gastrectomy preserves intestinal continuity but reduces gastric volume and may accelerate gastric emptying. Rosuvastatin is strongly influenced by transporters such as OATP1B1 and BCRP; losartan is affected by absorption and CYP2C9-mediated formation of its active metabolite E-3174. Direct comparative evidence between these procedures is limited.
Eligible adults will be enrolled before clinically indicated surgery. Surgical procedure selection is not assigned by the study. At each pharmacokinetic visit, after at least 8 hours of fasting, participants will receive single oral doses of rosuvastatin 10 mg and losartan 25 mg with 200 mL water. Venous plasma samples will be obtained at 0, 1.5, and 4 hours. Concentrations of rosuvastatin, losartan, and E-3174 will be quantified using validated HPLC-MS/MS. Individual AUC0-infinity, apparent clearance, half-life, and apparent volume of distribution will be estimated using MAP Bayesian methods informed by published population pharmacokinetic models. Clinical and laboratory covariates, including weight, BMI, lipid profile, blood pressure, comorbidities, and concomitant medications, will be recorded. In the 30-participant RYGB group only, paired stool samples will be analyzed by 16S rRNA sequencing and untargeted metabolomics. Safety will be monitored during and after each research dosing visit.
- Conditions
- Obesity & Overweight, Bariatric Surgery, Pharmacokinetics After Oral Intake, Drug Absorption
- Being tested
- Rosuvastatin, Losartan (Control)
- Keywords
- Roux-en-Y gastric bypass, sleeve gastrectomy, rosuvastatin, losartan, E-3174, gut microbiota, metabolomics, systemic exposure
- Medical subject headings
- Obesity, Overweight
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
RosuvastatinDrug
Rosuvastatin 10 mg tablet, single oral dose at each of two pharmacokinetic visits. Other name: rosuvastatin calcium.
Losartan (Control)Drug
Losartan 25 mg tablet, single oral dose at each of two pharmacokinetic visits. Other name: losartan potassium.
| Study group | Role | What they receive |
|---|---|---|
| Roux-en-Y Gastric Bypass Group | Experimental | Participants scheduled for clinically indicated laparoscopic RYGB receive a single oral research dose of rosuvastatin 10 mg plus losartan 25 mg within 30 days before surgery and again approximately 12 weeks after surgery. Plasma is collected at 0, 1.5, and 4 hours at each visit. Paired stool samples are collected before and after surgery for microbiome and untargeted metabolomics analyses. Receives: Drug: Rosuvastatin; Drug: Losartan (Control) |
| Sleeve Gastrectomy Group | Active comparator | Participants scheduled for clinically indicated laparoscopic sleeve gastrectomy receive the same single oral research doses and pharmacokinetic plasma sampling schedule before and approximately 12 weeks after surgery. Stool collection and microbiome/metabolomics analyses are not performed in this group. Receives: Drug: Rosuvastatin; Drug: Losartan (Control) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in rosuvastatin area under the plasma concentration-time curve extrapolated to infinity (AUC0-infinity)
Individual rosuvastatin AUC0-infinity will be estimated from plasma concentrations at 0, 1.5, and 4 hours using maximum a posteriori Bayesian estimation based on a published population pharmacokinetic model. Within-participant postoperative/preoperative geometric mean ratios and between-procedure differences will be estimated.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (postoperative visit may be delayed up to 6 months for clinical safety).
Change in losartan area under the plasma concentration-time curve extrapolated to infinity (AUC0-infinity)
Individual losartan AUC0-infinity will be estimated using the same sparse-sampling MAP Bayesian strategy and a published parent-metabolite population model.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Secondary outcomes (11)
Change in apparent oral clearance (CL/F) of rosuvastatin, losartan, and E-3174; same two study visits.
Change in apparent oral clearance (CL/F) of rosuvastatin, losartan, and E-3174; same two study visits.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Change in estimated elimination half-life of rosuvastatin, losartan, and E-3174; same two study visits.
Change in estimated elimination half-life of rosuvastatin, losartan, and E-3174; same two study visits.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Change in plasma concentrations of rosuvastatin, losartan, and E-3174 at 1.5 and 4 hours after the single oral dose; each pharmacokinetic visit.
Change in plasma concentrations of rosuvastatin, losartan, and E-3174 at 1.5 and 4 hours after the single oral dose; each pharmacokinetic visit.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Incidence of adverse events following research test dosing, assessed from dose administration through completion of the 4-hour observation period at each visit and by clinically indicated follow-up.
Incidence of adverse events following research test dosing, assessed from dose administration through completion of the 4-hour observation period at each visit and by clinically indicated follow-up.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
In the RYGB group only (30 participants), change in gut microbial in paired stool samples
In the RYGB group only (30 participants), change in gut microbial alpha diversity (Shannon and Simpson indices) in paired stool samples; preoperative and approximately 12 weeks postoperative.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
In the RYGB group only (30 participants), differential abundance of gut microbial taxa in paired stool samples
In the RYGB group only (30 participants), differential abundance of gut microbial taxa in paired stool samples; preoperative and approximately 12 weeks postoperative.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Change in apparent volume of distribution of rosuvastatin, losartan, and E-3174; same two study visits.
Change in apparent volume of distribution of rosuvastatin, losartan, and E-3174; same two study visits.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months
In the RYGB group only (30 participants), change in beta diversity (Bray-Curtis, Jensen-Shannon, and Jaccard distances) in paired stool samples; preoperative and approximately 12 weeks postoperative.
In the RYGB group only (30 participants), change in beta diversity (Bray-Curtis, Jensen-Shannon, and Jaccard distances) in paired stool samples; preoperative and approximately 12 weeks postoperative.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
In the RYGB group only (30 participants), change in untargeted fecal metabolomic features in paired stool samples; preoperative and approximately 12 weeks postoperative.
In the RYGB group only (30 participants), change in untargeted fecal metabolomic features in paired stool samples; preoperative and approximately 12 weeks postoperative.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Pearson Correlation Between Percent Change in Rosuvastatin Systemic Exposure and Change in Gut Microbiota Shannon Diversity Index
Pearson correlation between percent change in rosuvastatin AUC0-inf and change in gut microbiota alpha diversity. Plasma concentrations are measured by HPLC-MS/MS at predose, 1.5, and 4 hours; AUC0-inf (ng*h/mL) is estimated by maximum a posteriori Bayesian estimation. Percent AUC change = 100 x [(postoperative - preoperative)/preoperative]. In paired fecal samples from the Roux-en-Y gastric bypass group, V3-V4 16S rRNA sequencing with Illumina MiSeq is used to calculate the unitless Shannon Diversity Index; change = postoperative - preoperative. Pearson's r is unitless and ranges from -1 to +1. Positive values indicate changes in the same direction, negative values indicate changes in opposite directions, and absolute values closer to 1 indicate stronger correlation.
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety)
Pearson Correlation Between Change in Losartan AUC0-inf and Change in Gut Microbiota Shannon Diversity Index
Pearson correlation between percent change in losartan AUC0-inf and change in gut microbiota alpha diversity. Plasma concentrations are measured by HPLC-MS/MS at predose, 1.5, and 4 hours; AUC0-inf (ng*h/mL) is estimated by maximum a posteriori Bayesian estimation. Percent AUC change = 100 x [(postoperative - preoperative)/preoperative]. In paired fecal samples from the Roux-en-Y gastric bypass group, V3-V4 16S rRNA sequencing with Illumina MiSeq is used to calculate the unitless Shannon Diversity Index; change = postoperative - preoperative. Pearson's r is unitless and ranges from -1 to +1. Positive values indicate changes in the same direction, negative values indicate changes in opposite directions, and absolute values closer to 1 indicate stronger correlation.
Time Frame
Measured: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Aug 2026
- Study start2 Aug 2026 (estimated)
- Primary completion15 May 2027 (estimated)
- Study completion15 May 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Obesity & OverweightStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- Participants enter the RYGB or sleeve gastrectomy group according to the operation selected for clinical care. Within each group, every participant undergoes identical paired pharmacokinetic test-dose visits before and after surgery.
- Masking
- None (open label)
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Hospital das Clínicas de Ribeirão Preto
- Sponsor type
- University, hospital or other
- Collaborators
- School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo
- Responsible party
- Sponsor
- Investigators
- Wilson Salgado Jr, MD PhD, Principal investigator, Medical School of Ribeirao Preto, University of Sao Paulo
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07748273
- Sponsor's protocol ID
- HCFMRP-PK-BARI-2026
- Other IDs
- CAAE 98218026.5.0000.5440
- Acronym
- BARI-PK
- Status last verified
- Jul 2026
- First submitted
- 22 Jul 2026
- Last updated
- 5 Aug 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Deidentified individual participant data underlying the results reported in peer-reviewed publications may be shared, together with the data dictionary, study protocol, and statistical analysis plan. Requests must include a scientifically sound proposal, analysis plan, and evidence of ethics and institutional approvals where applicable. Access will be subject to a data-use agreement and protection of participant confidentiality.
Study at a glance
From the registry record, last updated by the sponsor on 5 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparative Evaluation of Rosuvastatin and Losartan Pharmacokinetics and the Associations Between Gut Microbiota Alterations and Changes in Systemic Drug Exposure in Patients Undergoing Roux-en-Y Gastric Bypass or Sleeve Gastrectomy
- ClinicalTrials.gov ID
- NCT07748273
- Acronym / sponsor ID
- BARI-PK / HCFMRP-PK-BARI-2026
- Conditions
- Obesity & Overweight, Bariatric Surgery, Pharmacokinetics After Oral Intake, Drug Absorption
- Keywords
- Roux-en-Y gastric bypass, sleeve gastrectomy, rosuvastatin, losartan, E-3174, gut microbiota, metabolomics, systemic exposure
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- Hospital das Clínicas de Ribeirão PretoUniversity, hospital or other
- Collaborators
- School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo
- Study start
- 2 Aug 2026 (estimated)
- Primary completion
- 15 May 2027 (estimated)
- Study completion
- 15 May 2027 (estimated)
- First posted
- 5 Aug 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This prospective, open-label, non-randomized pharmacokinetic study will evaluate how Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy affect systemic exposure to single oral test doses of rosuvastatin and losartan. Sixty adults scheduled for bariatric surgery will enter one of two parallel groups according to the clinically selected operation (30 RYGB and 30 sleeve gastrectomy). Each participant will receive rosuvastatin 10 mg and losartan 25 mg once within 30 days before surgery and again approximately 12 weeks after surgery. Plasma samples collected before dosing and at 1.5 and 4 hours after dosing will be used with maximum a posteriori Bayesian estimation to estimate individual pharmacokinetic parameters. In the 30-participant RYGB group only, paired stool samples will be used to explore gut microbiota and untargeted fecal metabolomic changes. The primary objective is to compare within-participant changes and between-procedure differences in drug exposure after bariatric surgery.
Detailed description
Anatomical and physiological changes after bariatric surgery may alter oral drug absorption, first-pass metabolism, transporter activity, and systemic exposure. RYGB bypasses the duodenum and proximal jejunum, whereas sleeve gastrectomy preserves intestinal continuity but reduces gastric volume and may accelerate gastric emptying. Rosuvastatin is strongly influenced by transporters such as OATP1B1 and BCRP; losartan is affected by absorption and CYP2C9-mediated formation of its active metabolite E-3174. Direct comparative evidence between these procedures is limited.
Eligible adults will be enrolled before clinically indicated surgery. Surgical procedure selection is not assigned by the study. At each pharmacokinetic visit, after at least 8 hours of fasting, participants will receive single oral doses of rosuvastatin 10 mg and losartan 25 mg with 200 mL water. Venous plasma samples will be obtained at 0, 1.5, and 4 hours. Concentrations of rosuvastatin, losartan, and E-3174 will be quantified using validated HPLC-MS/MS. Individual AUC0-infinity, apparent clearance, half-life, and apparent volume of distribution will be estimated using MAP Bayesian methods informed by published population pharmacokinetic models. Clinical and laboratory covariates, including weight, BMI, lipid profile, blood pressure, comorbidities, and concomitant medications, will be recorded. In the 30-participant RYGB group only, paired stool samples will be analyzed by 16S rRNA sequencing and untargeted metabolomics. Safety will be monitored during and after each research dosing visit.
Study design
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Participants enter the RYGB or sleeve gastrectomy group according to the operation selected for clinical care. Within each group, every participant undergoes identical paired pharmacokinetic test-dose visits before and after surgery.
| Arm | Type | Receives |
|---|---|---|
| Roux-en-Y Gastric Bypass Group | Experimental | Drug: Rosuvastatin, Drug: Losartan (Control)Participants scheduled for clinically indicated laparoscopic RYGB receive a single oral research dose of rosuvastatin 10 mg plus losartan 25 mg within 30 days before surgery and again approximately 12 weeks after surgery. Plasma is collected at 0, 1.5, and 4 hours at each visit. Paired stool samples are collected before and after surgery for microbiome and untargeted metabolomics analyses. |
| Sleeve Gastrectomy Group | Active comparator | Drug: Rosuvastatin, Drug: Losartan (Control)Participants scheduled for clinically indicated laparoscopic sleeve gastrectomy receive the same single oral research doses and pharmacokinetic plasma sampling schedule before and approximately 12 weeks after surgery. Stool collection and microbiome/metabolomics analyses are not performed in this group. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Adults aged 18 to 65 years;
- Formal clinical indication for RYGB or sleeve gastrectomy after multidisciplinary assessment;
- Bariatric surgery scheduled and no previous bariatric procedure;
- Able to understand the study and provide written informed consent.
Key exclusion criteria (8 listed)
- Moderate or severe hepatic impairment, liver enzymes greater than 3 times the upper limit of normal, or Child-Pugh class B or C.
- Estimated glomerular filtration rate below 30 mL/min/1.73 m².
- Concomitant use of drugs that substantially affect rosuvastatin pharmacokinetics and cannot be temporarily discontinued, including cyclosporine, gemfibrozil, or potent OATP1B1/BCRP or CYP2C9 inhibitors.
- Systemic antibiotic use within 3 months or probiotic, prebiotic, or synbiotic use within 4 weeks before sampling.
- Continuous current rosuvastatin or other statin therapy unless medically discontinued with an adequate washout period under physician supervision.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| RosuvastatinRosuvastatin 10 mg tablet, single oral dose at each of two pharmacokinetic visits. Other name: rosuvastatin calcium. | Drug | Roux-en-Y Gastric Bypass Group, Sleeve Gastrectomy Group |
| Losartan (Control)Losartan 25 mg tablet, single oral dose at each of two pharmacokinetic visits. Other name: losartan potassium. | Drug | Roux-en-Y Gastric Bypass Group, Sleeve Gastrectomy Group |
Primary outcome
Change in rosuvastatin area under the plasma concentration-time curve extrapolated to infinity (AUC0-infinity)
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (postoperative visit may be delayed up to 6 months for clinical safety).
Individual rosuvastatin AUC0-infinity will be estimated from plasma concentrations at 0, 1.5, and 4 hours using maximum a posteriori Bayesian estimation based on a published population pharmacokinetic model. Within-participant postoperative/preoperative geometric mean ratios and between-procedure differences will be estimated.
Change in losartan area under the plasma concentration-time curve extrapolated to infinity (AUC0-infinity)
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Individual losartan AUC0-infinity will be estimated using the same sparse-sampling MAP Bayesian strategy and a published parent-metabolite population model.
11 secondary outcomes
Change in apparent oral clearance (CL/F) of rosuvastatin, losartan, and E-3174; same two study visits.
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Change in estimated elimination half-life of rosuvastatin, losartan, and E-3174; same two study visits.
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Change in plasma concentrations of rosuvastatin, losartan, and E-3174 at 1.5 and 4 hours after the single oral dose; each pharmacokinetic visit.
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Incidence of adverse events following research test dosing, assessed from dose administration through completion of the 4-hour observation period at each visit and by clinically indicated follow-up.
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
In the RYGB group only (30 participants), change in gut microbial in paired stool samples
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
In the RYGB group only (30 participants), differential abundance of gut microbial taxa in paired stool samples
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Change in apparent volume of distribution of rosuvastatin, losartan, and E-3174; same two study visits.
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months
In the RYGB group only (30 participants), change in beta diversity (Bray-Curtis, Jensen-Shannon, and Jaccard distances) in paired stool samples; preoperative and approximately 12 weeks postoperative.
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
In the RYGB group only (30 participants), change in untargeted fecal metabolomic features in paired stool samples; preoperative and approximately 12 weeks postoperative.
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Pearson Correlation Between Percent Change in Rosuvastatin Systemic Exposure and Change in Gut Microbiota Shannon Diversity Index
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety)
Pearson Correlation Between Change in Losartan AUC0-inf and Change in Gut Microbiota Shannon Diversity Index
Time frame: Within 30 days before surgery and approximately 12 weeks after surgery (up to 6 months if delayed for clinical safety).
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Aug 2026.
- Individual participant dataSharing planned: Yes. Deidentified individual participant data underlying the results reported in peer-reviewed publications may be shared, together with the data dictionary, study protocol, and statistical analysis plan. Requests must include a scientifically sound proposal, analysis plan, and evidence of ethics and institutional approvals where applicable. Access will be subject to a data-use agreement and protection of participant confidentiality.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Wilson Salgado Jr, MD PhD principal investigator
Medical School of Ribeirao Preto, University of Sao Paulo
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Rosuvastatin in people with Obesity & Overweight and Bariatric Surgery, run by Hospital das Clínicas de Ribeirão Preto at 1 site in Brazil.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 5 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Brazil. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Wilson Salgado Jr, MD, PhD (+5516981564846, wsalgado@fmrp.usp.br), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in rosuvastatin area under the plasma concentration-time curve extrapolated to infinity (AUC0-infinity) (time frame: Within 30 days before surgery and approximately 12 weeks after surgery (postoperative visit may be delayed up to 6 months for clinical safety).). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Aug 2026.