ACL InjuryPhase 4NCT07135687
Study to Use Oral Losartan to Decrease the Risk of Postoperative Scarring Following (ACL) Reconstruction
A Phase 4 study testing Losartan in people with ACL Injury and ACL Reconstruction, run by Rush University Medical Center at 1 site in United States.
Trial summary
The purpose of this study to investigate the effect of using losartan (a blood pressure lowering drug with anti-scarring properties) on preventing primary postoperative arthrofibrosis (formation of abnormal scar tissue) in the knees in participants undergoing anterior cruciate ligament (ACL) repair surgery of their… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- ACL Injury, ACL Reconstruction, Scar Formation
- What is being tested?
- Losartan
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 144 participants
- Where
- 1 siteUnited States
- Study dates
- Aug 2026to Dec 2028
- Phase
- Phase 4
- 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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Must be undergoing a primary ACLR with or without the following:
- Chondroplasty
- Synovectomy
- Loose body removal
- Removal of hardware
- Meniscal surgery (excluding meniscal allograft transplantation/MAT)
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- Lateral extra-articular tenodesis
- Must have skeletal maturity in the distal femur and proximal tibial physes
- Must be age 18 years or older at time of enrollment
Who cannot join
- <18 years at time of enrollment
- No diagnosis of ACL tear
- ACL repairs
- Revision ACL reconstructions
- Open distal femur or proximal tibia physes
- Major concomitant procedures (such as osteotomy, MAT, or cartilage restoration surgery)
Show all 17Show fewer
- History of prior proximal or distal femur fracture (including those receiving nonoperative treatment)
- History of prior ipsilateral femur or tibia osteomyelitis
- Medical history
- History of hypotensive disease, including postural orthostatic hypotension syndrome (POTS), autonomic dysreflexia, or Shy-Drager syndrome (aka multiple system atrophy), baseline hypotension <90 systolic or <60 diastolic mmHg.
- History of significant hepatic disease (liver transplantation, cirrhosis of any cause, or any liver disease with Child-Pugh classification B or C) due to hepatic metabolism of ARBs.
- Chronic kidney disease
- Rheumatologic disorders on immunologic medications
- Current medications including diuretics (i.e. furosemide), lithium, and spironolactone
- Current hypertension with prescription of an ARB or ACE-I
- Allergy to losartan
- Current pregnancy or breastfeeding
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Andrew Bi, MD contact
United States1 site
Rush University Medical Center
Chicago, Illinois, 60612
Andrew BI, MD, Andrew.Bi@rushortho.com
Jorge Chahla, MD, PhD, Jorge.Chahla@rushortho.com
About this study
Official title: Oral Losartan to Decrease the Risk of Postoperative Arthrofibrosis Following Primary and Revision Anterior Cruciate Ligament Reconstruction
The purpose of this study to investigate the effect of using losartan (a blood pressure lowering drug with anti-scarring properties) on preventing primary postoperative arthrofibrosis (formation of abnormal scar tissue) in the knees in participants undergoing anterior cruciate ligament (ACL) repair surgery of their knee.
Read the detailed description
Losartan, an angiotensin-II receptor blocker (ARB), approved by the Food and Drug Administration (FDA) for the treatment of hypertension and diabetic nephropathy, has garnered recent interest in the field of orthopedic surgery as an anti-fibrotic (anti-scarring) agent. Losartan's primary mechanism of action as an anti-hypertensive involves acting as a receptor antagonist for angiotensin II, a peptide produced by the liver which causes vasoconstriction, release of anti-diuretic hormone from the pituitary gland, and release of aldosterone from the adrenal glands, among other functions. Losartan secondary function is to act as a TGF-β1 blocker. TGF-β1 has been implicated in pro-fibrotic pathways in multiple organs systems. Losartan, initially as a treatment for hypertension and diabetic nephropathy, was found to have benefits against fibrosis in the renal system. As a result, the use of losartan has gained interest in several other fields in medicine, including plastic surgery for wound healing and keloid prevention, in ophthalmology to prevent corneal scarring, and orthopedic surgery. The potential use of losartan presents an attractive anti-fibrotic prophylaxis candidate against the formation of postoperative arthrofibrosis following ACLR.
- Conditions
- ACL Injury, ACL Reconstruction, Scar Formation
- Being tested
- Losartan, Placebo
- Keywords
- ACL, Postoperative Arthrofibrosis, Losartan
- Medical subject headings
- Anterior Cruciate Ligament Injuries
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
LosartanDrug
Two types of losartan capsules will be compounded by combining a broken-up 25mg or 50mg losartan tablet and microcrystalline cellulose placebo filler to eliminate rattling of the broken tablet inside of the capsule. The 25mg losartan capsules will be yellow and the 50 mg losartan capsules will be blue.
PlaceboOther
The placebo capsules will consist of microcrystal cellulose and will come in yellow and blue to appear identical to the losartan capsules.
| Study group | Role | What they receive |
|---|---|---|
| Losartan | Experimental | The experimental arm (Arm 1) will receive 25mg losartan daily for 3 days followed by 50 mg losartan daily for 25 days. Receives: Drug: Losartan |
| Placebo | Placebo comparator | The placebo arm (Arm 2) will receive a placebo tablet with the same appearance and frequency to that of the losartan group. Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Range of Motion
Range of motion measured from baseline to 12 months
Measured: 12 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Aug 2025
- Study startAug 2026 (estimated)
- Primary completionOct 2028 (estimated)
- Study completionDec 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for ACL InjuryStudies 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 4
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 144 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Rush University Medical Center
- Sponsor type
- University, hospital or other
- Collaborators
- Arthroscopy Association of North America
- Responsible party
- Sponsor
- Investigators
- Jorge Chahla, MD, PhD, Principal investigator, Rush University Medical CenterAndrew Bi, MD, Principal investigator, Rush University Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07135687
- Sponsor's protocol ID
- 24120601
- Status last verified
- Dec 2025
- First submitted
- 14 Aug 2025
- Last updated
- 15 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 15 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Oral Losartan to Decrease the Risk of Postoperative Arthrofibrosis Following Primary and Revision Anterior Cruciate Ligament Reconstruction
- ClinicalTrials.gov ID
- NCT07135687
- Acronym / sponsor ID
- 24120601
- Conditions
- ACL Injury, ACL Reconstruction, Scar Formation
- Keywords
- ACL, Postoperative Arthrofibrosis, Losartan
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 144 participants (estimated)
- Lead sponsor
- Rush University Medical CenterUniversity, hospital or other
- Collaborators
- Arthroscopy Association of North America
- Study start
- Aug 2026 (estimated)
- Primary completion
- Oct 2028 (estimated)
- Study completion
- Dec 2028 (estimated)
- First posted
- 22 Aug 2025 (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.
The purpose of this study to investigate the effect of using losartan (a blood pressure lowering drug with anti-scarring properties) on preventing primary postoperative arthrofibrosis (formation of abnormal scar tissue) in the knees in participants undergoing anterior cruciate ligament (ACL) repair surgery of their knee.
Detailed description
Losartan, an angiotensin-II receptor blocker (ARB), approved by the Food and Drug Administration (FDA) for the treatment of hypertension and diabetic nephropathy, has garnered recent interest in the field of orthopedic surgery as an anti-fibrotic (anti-scarring) agent. Losartan's primary mechanism of action as an anti-hypertensive involves acting as a receptor antagonist for angiotensin II, a peptide produced by the liver which causes vasoconstriction, release of anti-diuretic hormone from the pituitary gland, and release of aldosterone from the adrenal glands, among other functions. Losartan secondary function is to act as a TGF-β1 blocker. TGF-β1 has been implicated in pro-fibrotic pathways in multiple organs systems. Losartan, initially as a treatment for hypertension and diabetic nephropathy, was found to have benefits against fibrosis in the renal system. As a result, the use of losartan has gained interest in several other fields in medicine, including plastic surgery for wound healing and keloid prevention, in ophthalmology to prevent corneal scarring, and orthopedic surgery. The potential use of losartan presents an attractive anti-fibrotic prophylaxis candidate against the formation of postoperative arthrofibrosis following ACLR.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Losartan | Experimental | Drug: LosartanThe experimental arm (Arm 1) will receive 25mg losartan daily for 3 days followed by 50 mg losartan daily for 25 days. |
| Placebo | Placebo comparator | Other: PlaceboThe placebo arm (Arm 2) will receive a placebo tablet with the same appearance and frequency to that of the losartan group. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (9 listed)
- Must be undergoing a primary ACLR with or without the following:
- Chondroplasty
- Synovectomy
- Loose body removal
- Removal of hardware
Key exclusion criteria (17 listed)
- <18 years at time of enrollment
- No diagnosis of ACL tear
- ACL repairs
- Revision ACL reconstructions
- Open distal femur or proximal tibia physes
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 |
|---|---|---|
| LosartanTwo types of losartan capsules will be compounded by combining a broken-up 25mg or 50mg losartan tablet and microcrystalline cellulose placebo filler to eliminate rattling of the broken tablet inside of the capsule. The 25mg losartan capsules will be yellow and the 50 mg losartan capsules will be blue. | Drug | Losartan |
| PlaceboThe placebo capsules will consist of microcrystal cellulose and will come in yellow and blue to appear identical to the losartan capsules. | Other | Placebo |
Primary outcome
Range of Motion
Time frame: 12 months
Range of motion measured from baseline to 12 months
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 15 Dec 2025.
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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.
Andrew Bi, MD contact
Jorge Chahla, MD, PhD principal investigator
Rush University Medical Center
Andrew Bi, MD principal investigator
Rush University Medical Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Losartan in people with ACL Injury and ACL Reconstruction, run by Rush University Medical Center at 1 site in United States.
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 9 inclusion and 17 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 15 Dec 2025. 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 United States. 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. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
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 Jorge Chahla, MD, PhD ((312) 432-2452, Jorge.chahla@rushortho.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Range of Motion (time frame: 12 months). 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 15 Dec 2025.