How weight-loss surgery changes absorption of rosuvastatin and losartan
Tests two oral medicines in adults with obesity before and after weight-loss surgery.
Plain-language title generated from the registry record
Registry title: Rosuvastatin and Losartan Pharmacokinetics After Bariatric Surgery
Key facts
- Where
- Ribeirão Preto, BrazilSee the site
AI summary: who the study is looking for
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults aged 18 to 65 who are scheduled for Roux-en-Y gastric bypass or sleeve gastrectomy weight-loss surgery. It studies how the surgery changes the body's exposure to rosuvastatin and losartan.
- Age
- 18 to 65 years
- Sex
- All sexes can join.
- Disease stage
- A formal clinical indication for Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy, with surgery scheduled.
- Earlier treatment
- No previous bariatric surgery. Current statin treatment is not allowed unless it was stopped under a doctor's care with enough time off the drug.
Main reasons for not taking part
- Moderate or severe liver problems, or liver enzymes above 3 times the upper limit of normal
- Estimated glomerular filtration rate below 30 mL/min/1.73 m²
- Taking drugs that strongly affect rosuvastatin, such as cyclosporine or gemfibrozil, that cannot be paused
- Antibiotics within 3 months, or probiotics, prebiotics or synbiotics within 4 weeks before sampling
- Pregnancy
Read by machine on 9 November 2026.
Could this be for you?
Answer for yourself. This is not a decision: only the study team can say whether you can take part.
- Are you between 18 and 65 years old?
Source: NCT07748273, who can take part
Where in Brazil
- Hospital das Clínicas, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, BrazilNo longer taking part
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Contact the study team: see the registry record → Contacts and Locations
Print a page for my doctorTrial details
- Who runs it
- Hospital das Clínicas de Ribeirão Preto
- Trial code
- NCT07748273
- Record updated
- 5 August 2026
- Original description
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 full original descriptionShow less
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.
Inclusion: 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.
Exclusion: 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; Moderate or severe hepatic impairment, liver enzymes greater than 3 times the upper limit of normal, or Child-Pugh class B or C; Clinically relevant baseline hypotension, significant hyperkalemia, renal impairment, or another condition that makes a losartan test dose unsafe; Estimated glomerular filtration rate below 30 mL/min/1.73 m²; 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.