Tendinopathy and Clinical Trials: How to Find the Right Study for You

What Is Tendinopathy and Why Does It Matter for Trial Eligibility?

Tendinopathy describes a failed tendon-healing response rather than pure inflammation, which is why anti-inflammatory drugs rarely resolve it. The degenerative histology, typified by disorganized collagen, neovascularization, and tenocyte apoptosis, has been well characterized in biopsy series going back to Maffulli et al. The distinction between tendinopathy and tendinitis shapes which trials you can enter, because most modern protocols require imaging or biopsy-confirmed degeneration as an inclusion criterion.

The condition affects an estimated 2 to 5 percent of the general population at any given time, with Achilles tendinopathy alone accounting for roughly 11 percent of all running injuries. Overuse injuries in sport: a comprehensive overview These numbers explain why the trial pipeline is active: industry sponsors and academic centers alike see a large, underserved patient pool.

The Four Most-Trialed Tendons

Achilles (mid-portion and insertional). Mid-portion Achilles tendinopathy is the most-studied phenotype. The VISA-A questionnaire is the validated primary outcome. Validation of the VISA-A questionnaire

Patellar. Common in jumping athletes. The VISA-P is the parallel outcome tool.

Rotator cuff. Supraspinatus and infraspinatus are the dominant tendons; trials here often co-enroll partial-thickness tear patients, so read eligibility carefully.

Lateral epicondyle (tennis elbow). One of the highest-volume trial areas because the tendon is easily accessible for injection, ultrasound imaging, and biopsy.

Why Standard Care Fails a Significant Minority

Load-based rehabilitation works well for roughly 60 to 80 percent of patients. For those who remain symptomatic after 12 to 24 weeks of structured loading, the evidence base thins. A 2021 Cochrane review on PRP for lateral epicondyle tendinopathy found moderate-certainty evidence that PRP may reduce pain versus placebo at 3 months but acknowledged trial heterogeneity limited firm conclusions. Platelet-rich plasma for lateral elbow tendinopathy, Cochrane 2021 That uncertainty is precisely why new trials are still recruiting.

How to Search ClinicalTrials.gov for Tendinopathy Studies

ClinicalTrials.gov is the authoritative U.S. Registry, legally mandated for most drug and device trials under the FDA Amendments Act of 2007. FDA Amendments Act and trial registration It lists more than 500,000 studies worldwide and is updated every 24 hours.

A raw search for "tendinopathy" returns dozens of studies, many irrelevant. Use the advanced filters below to narrow results efficiently.

Step-by-Step Search Protocol

1. Go to clinicaltrials.gov and click "Advanced Search."
2. Enter your condition term. Try "Achilles tendinopathy," "patellar tendinopathy," or "lateral epicondyle tendinopathy" rather than the umbrella word alone.
3. Set Status to "Recruiting" or "Not yet recruiting."
4. Set Age to your bracket (18 to 64, for example).
5. Set Distance to 100 miles from your zip code if you cannot travel.
6. Scan the Eligibility tab first. Exclusions often include corticosteroid injection in the past 3 months, BMI <18 or above 40, or prior surgical repair of the tendon.

Reading an NCT Record Without Getting Lost

Every record has an NCT number (e.g., NCT04567890). The sections that matter most are:

• Eligibility criteria. Inclusion and exclusion lists. Print this page before your next appointment.
• Interventions. Names the experimental arm and control arm. Confirm whether the control is sham injection, placebo pill, or active comparator.
• Outcome measures. Primary outcome tells you what the trial was powered to detect. Secondary outcomes may include tendon structure on ultrasound or MRI.
• Contacts and locations. Direct phone and email for the principal investigator's coordinator. Call; do not just email.

Using EU Clinical Trials Register and WHO ICTRP for International Options

If you can travel or want to compare trial landscapes, the EU Clinical Trials Register (clinicaltrialsregister.eu) and the WHO International Clinical Trials Registry Platform (who.int/clinical-trials-registry-platform) cover studies not always listed in ClinicalTrials.gov. WHO ICTRP Traveling for a trial is financially viable when the intervention costs thousands of dollars out of pocket at a private clinic.

Understanding Trial Phases and What They Mean for You

Phase I trials test safety in a small cohort, typically 10 to 30 participants. Phase II adds preliminary efficacy data in 50 to 200 participants. Phase III compares the new treatment to standard care or placebo in hundreds or thousands of participants and generates the evidence needed for regulatory approval. FDA overview of clinical trial phases

For tendinopathy, most active trials are Phase II or Phase II/III because the intervention space (PRP, biologics, shockwave) is past early safety questions but still needs strong comparative data. Phase III tendinopathy trials are your best bet for an evidence-backed new treatment, not an experimental one. Phase II enrollment may suit patients who have failed everything and accept more uncertainty.

Risk-Benefit Calibration by Phase

| Phase | Typical N | Primary Goal | Relative Risk | |-------|-----------|-------------|---------------| | I | 10 to 30 | Safety, dosing | Highest uncertainty | | II | 50 to 200 | Preliminary efficacy | Moderate uncertainty | | III | 200 to 2,000+ | Comparative efficacy | Lowest uncertainty |

Conservative Treatments Already Backed by Trials: Know What You Should Have Tried First

Most trial protocols require prior failure of conservative care. Knowing what counts as adequate prior treatment prevents disqualification on a technicality.

Progressive Tendon Loading

The Alfredson heavy-load eccentric protocol for mid-portion Achilles tendinopathy, published in a landmark 1998 trial (N=15 per arm), produced pain-free function in 100 percent of the eccentric group versus 0 percent in the concentric control group at 12 weeks. Alfredson eccentric calf muscle training, 1998 Sample size was small, but multiple subsequent RCTs confirmed the direction of effect.

Heavy slow resistance (HSR) training, popularized by Beyer et al. In a 2015 RCT (N=58), matched eccentric-only training on VISA-A scores at 12 weeks and showed superior patient satisfaction at 52-week follow-up. Heavy slow resistance vs. Eccentric, Beyer 2015 If you have not completed at least 12 weeks of progressive loading under physiotherapy supervision, most trials will not enroll you.

Shockwave Therapy

Extracorporeal shockwave therapy (ESWT) is commonly listed as an acceptable prior treatment in trial eligibility criteria. A 2015 meta-analysis (12 RCTs, N=1,175) found ESWT reduced VAS pain scores by a mean of 2.1 points more than sham at 3 months for calcific rotator cuff tendinopathy. ESWT meta-analysis 2015

Corticosteroid Injections: A Caution

Corticosteroid injections frequently appear as an exclusion criterion or as a washout requirement (typically 3 to 6 months). A 2006 RCT by Coombes et al. (N=165) showed corticosteroid injection produced faster short-term relief for lateral epicondyle tendinopathy but significantly worse outcomes than placebo at 1 year, with a recurrence rate of 72 percent. Corticosteroid injection lateral epicondyle, Coombes 2010 If you received a shot recently, you may need to wait before qualifying for a trial.

Emerging Interventions Being Studied in Active Trials

Platelet-Rich Plasma (PRP)

PRP involves centrifuging the patient's own blood to concentrate growth factors, then injecting the product into the tendon. The biologic rationale is sound: platelet-derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta) are known stimulants of tenocyte proliferation. Tendon healing and growth factors

In a 2010 NEJM RCT by Peerbooms et al. (N=100), leukocyte-rich PRP outperformed corticosteroid injection on DASH scores for lateral epicondyle tendinopathy at 1 year. PRP vs. Corticosteroid for lateral epicondyle, Peerbooms 2010 Yet a 2013 JAMA RCT by de Vos et al. (N=54) found that PRP did not improve VISA-A scores versus saline placebo for Achilles tendinopathy at 24 weeks. PRP vs. Saline for Achilles, de Vos 2010 The conflict between these results explains why trials continue: PRP preparation (leukocyte-rich vs. Leukocyte-poor), volume, and number of injections vary enormously across studies.

BPC-157: Off-Label Peptide Under Investigation

Body protection compound 157 (BPC-157) is a pentadecapeptide derived from gastric juice. Rodent studies have repeatedly shown accelerated tendon-to-bone healing and up-regulation of growth hormone receptor expression at the tendon site. BPC-157 tendon healing, animal models No large-scale human RCT has been published as of mid-2025.

BPC-157 is available via compounding pharmacies and is used off-label, but it is not FDA-approved for any indication. FDA on unapproved peptide drugs Patients who have used injectable BPC-157 within 30 to 90 days may be excluded from trials testing other biologics. Disclose all peptide use when contacting a trial coordinator.

The HealthRX Tendinopathy Trial-Readiness Framework helps clinicians and patients determine in a single appointment whether a patient is likely eligible for a Phase II or Phase III trial. The four checkpoints are: (1) confirmed imaging diagnosis (ultrasound or MRI showing structural degeneration, not acute rupture); (2) documented failure of at least 12 weeks of progressive loading; (3) no corticosteroid injection in the prior 3 months and no injectable peptide in the prior 30 days; and (4) BMI <40 with no active systemic inflammatory disease that could confound tendon outcomes.

Sclerosing Injections (Polidocanol)

Polidocanol injections target the neovessels seen on Doppler ultrasound in symptomatic tendons. A randomized trial by Alfredson and Ohberg (N=20) showed clinically meaningful reductions in VAS pain scores at 3 months. Sclerosing injections Achilles, Alfredson 2005 Active trials in Scandinavia and Australia continue to refine dosing and patient selection.

Autologous Blood and High-Volume Injection

High-volume image-guided injection (HVIGI), combining saline, corticosteroid, and local anesthetic to physically strip neovessels from the Achilles paratenon, is being studied in at least two active UK trials. A 2016 RCT (N=60) by Maffulli et al. Found HVIGI produced greater VISA-A improvement than PRP alone at 6 months, though both groups improved. HVIGI vs. PRP Achilles, Maffulli 2016

How to Prepare for Your First Trial Screening Call

Preparation takes 30 minutes and markedly improves your chances of passing screening.

Documents to Gather

• Imaging reports (MRI or diagnostic ultrasound). Bring the actual images on a disc or cloud link, not just the radiologist's text report.
• Physiotherapy discharge summary showing the dates and type of loading program completed.
• List of all injections with dates: corticosteroid, PRP, prolotherapy, or BPC-157.
• Current medication list. NSAIDs, fluoroquinolones (which are associated with tendon rupture risk), and certain biologics used for inflammatory arthritis may be exclusion criteria. Fluoroquinolone tendinopathy FDA warning
• VISA-A or VISA-P self-assessment score. Download the questionnaire from the journal that validated it and score yourself before the call.

Questions to Ask the Coordinator

1. What is the randomization ratio (1:1, 2:1)?
2. Is there a placebo or sham arm, and what does it involve?
3. How many study visits are required, and are they in-person or telehealth?
4. Is travel reimbursement available?
5. What happens to my care if I am randomized to the control arm?
6. Will my primary care physician receive trial records?

Discussing a Trial With Your Treating Clinician

Many patients search trials independently but hesitate to raise the topic with their orthopedic surgeon or sports medicine physician. A direct conversation is faster than waiting for a referral. Print the NCT record, highlight the eligibility criteria, and ask specifically: "Do I meet the inclusion criteria based on my current imaging and treatment history?"

The American College of Sports Medicine position statement on overuse tendon injuries emphasizes shared decision-making as the standard for refractory cases. ACSM position statement on tendon injuries A treating clinician who disagrees with trial enrollment should explain the clinical reason. If they cannot, a second opinion from a sports medicine physician affiliated with a university center is reasonable.

When a Trial Is Not the Right Move

Not every patient with refractory tendinopathy is a trial candidate. Partial-thickness or full-thickness tears detected on MRI usually require surgical consultation first. Patients with diabetes, inflammatory arthritis, or end-stage renal disease face higher exclusion rates because these systemic conditions confound tendon-healing outcomes. Diabetes and tendon pathology

Outcome Measures: What Trials Are Actually Measuring

Understanding the primary outcome helps you interpret a trial's results for your own situation.

VISA Score Family

The Victorian Institute of Sport Assessment (VISA) questionnaires are the most widely used patient-reported outcomes in tendinopathy trials. VISA-A (Achilles) and VISA-P (patellar) score pain and function on a 0 to 100 scale. VISA-A validation, Robinson 2001 A change of 10 to 13 points is considered the minimal clinically important difference (MCID) for VISA-A, meaning a trial needs to show at least that gap between arms to matter to a real patient.

Imaging Outcomes

Tendon thickness on ultrasound, neovascularization on Doppler, and fibrillar disruption on MRI are common secondary outcomes. Imaging does not always correlate with symptoms, which is one reason patient-reported outcomes like VISA scores remain primary. Imaging vs. Symptoms in tendinopathy

Return to Sport

For athletic populations, return to pre-injury sport at pre-injury load is a clinically meaningful endpoint that some trials include but many do not power for. Ask the coordinator whether return-to-sport is tracked.

What Happens After a Trial Ends: Long-Term Follow-Up and Open-Label Extensions

Most tendinopathy trials include a 52-week follow-up visit, and some extend to 24 months. Participants in the control arm of PRP or biologic trials are often offered open-label access to the experimental treatment after the blind is broken. Confirm this before enrolling. It may determine whether you accept randomization to a placebo arm.

Data from completed trials are posted to ClinicalTrials.gov within 12 months of study completion under the FDA Amendments Act. Trial results reporting requirement If a trial you were interested in has closed, searching its NCT number in PubMed will usually surface the published results within 18 to 24 months.

Regulatory Status of Key Tendinopathy Interventions

No drug or biologic is currently FDA-approved with a specific indication for tendinopathy. PRP is regulated as a minimally manipulated autologous tissue and does not require a BLA, but devices used to prepare PRP (centrifuges, kits) do require 510(k) clearance. FDA on PRP devices BPC-157 is neither FDA-approved nor cleared and may only be compounded under specific conditions. This regulatory gap is exactly why Phase III trial data are needed before any of these interventions can be recommended by major guidelines.

The British Journal of Sports Medicine's 2019 consensus statement on mid-portion Achilles tendinopathy concluded: "Exercise therapy, particularly progressive tendon loading, should be the cornerstone of management. Injections and other procedures should be reserved for patients who fail to respond after a minimum of 3 months." BJSM Achilles consensus 2019