If you have found a clinical trial that seems relevant to your situation and are now staring at a list of eligibility requirements you do not fully understand, you are in exactly the right place. The enrollment process for clinical trials has a defined structure, and knowing what each stage involves makes it far less intimidating to navigate. This guide explains what inclusion and exclusion criteria are, why they exist, what the formal screening process looks like from first contact through confirmed enrollment, and how to prepare at each step.
TLDR: Eligibility criteria in clinical trials are not arbitrary gatekeeping. They exist to protect participants and produce science that is actually reliable. The enrollment process has multiple stages, and meeting the written criteria in a study record does not guarantee acceptance into a trial. Screening involves a formal clinical evaluation that may include lab work, imaging, and a full medical history review. Read on for a complete walkthrough of every step.
Important Disclaimer: Save My Fat does not provide FDA-approved treatments or cures for any disease or medical condition. Adipose tissue banking is a preservation service for potential future opportunities, not a therapeutic product. Banking adipose tissue today does not guarantee eligibility, access, or clinical benefit from any future therapy, clinical trial, or medical program. All content here is for educational and informational purposes only and does not constitute medical advice, diagnosis, or treatment recommendations. Patients must consult their own licensed healthcare professionals regarding all medical decisions.
You found a trial on ClinicalTrials.gov. The title matched something you or a family member is dealing with. You clicked through, and now you are looking at a section labeled “Eligibility Criteria” that lists a dozen or more specific requirements: age ranges, prior diagnoses, lab value thresholds, medication restrictions, and a list of conditions that would immediately disqualify you. You are not sure if you qualify, and you are not sure what happens if you contact the study team.
This is the experience of nearly everyone who has ever investigated clinical trial participation. The eligibility criteria section can feel like a wall, but it is actually a structured document that you can read systematically. The criteria exist for reasons that are grounded in patient safety and scientific necessity. A trial that enrolls participants who do not match the scientific question being asked produces results that cannot be trusted, and a trial that enrolls participants who face unknown safety risks from the intervention creates real harm. The criteria are there to prevent both problems.
This guide walks through the full picture: what inclusion and exclusion criteria are, how they are structured, what the real-world enrollment process looks like from first search to confirmed participation, what happens at a screening visit, and how to understand informed consent before you sign anything. Where relevant, examples from the regenerative medicine and adipose-derived cell research space are used to illustrate the concepts, because that is the landscape this educational resource covers. Nothing in this article is a treatment claim or a guarantee of access to any specific trial. It is a map of the process.
What Are Inclusion and Exclusion Criteria?
Every registered clinical trial operates under a written protocol, a formal scientific document that specifies the study design, the research question, the intervention being tested, the procedures involved, and the participant requirements. The eligibility criteria are one of the most carefully constructed parts of that protocol. According to the ClinicalTrials.gov Glossary, eligibility criteria are the requirements that must be met for a person to participate in a clinical study.
Inclusion criteria are the characteristics a participant must have in order to be eligible. They define the target population the researchers intend to study. A trial investigating an adipose-derived cell therapy for knee osteoarthritis, for example, might require that participants be between 40 and 75 years old, have a confirmed osteoarthritis diagnosis of a specific radiographic grade, and have tried conservative treatments without adequate relief.
Exclusion criteria are the characteristics that prevent participation, even when inclusion criteria are met. They exist to protect participants who might face additional risks from the intervention or whose presence in the study might compromise the integrity of the data. That same knee trial might exclude patients who have had recent joint surgery, who are currently taking immunosuppressive medications, who have an active infection, or who are pregnant.
The table below summarizes the structural difference between the two.
| Factor | Inclusion Criteria | Exclusion Criteria |
|---|---|---|
| Definition | Characteristics a participant MUST have | Characteristics that PREVENT participation |
| Purpose | Define the target study population | Protect participant safety and data integrity |
| Common Examples in Regenerative Medicine Trials | Age range, confirmed diagnosis, disease severity grade, prior treatment history | Active infection, recent surgery, certain medications, pregnancy, uncontrolled comorbidities |
| Who Determines Them | Principal investigator and study sponsor, reviewed by IRB | Same; based on scientific rationale and safety data |
Why These Criteria Exist
There are three core reasons researchers establish eligibility criteria, and understanding them helps make the requirements feel less arbitrary.
The first is participant safety. Every investigational product carries unknown risks, and criteria are designed to exclude participants who face disproportionate danger. A participant with a compromised immune system may respond very differently to a cell-based therapy than someone with a healthy baseline. The International Conference on Harmonisation E6(R2) Good Clinical Practice standard, which governs how clinical trials are designed and conducted globally, requires that protocols include clearly justified eligibility criteria grounded in the risk-benefit profile of the investigational product.
The second is data integrity. If a trial enrolls participants with widely different baseline characteristics, the results become difficult to interpret. A study that enrolls both very mild and very severe cases may find no effect not because the intervention does not work, but because the two groups are responding so differently that the effect is obscured. Tightly defined eligibility criteria ensure that results mean what researchers say they mean.
The third is scientific validity. The results of a trial are meant to apply to a specific population. If researchers enroll a population that does not match the intended patients, the results cannot reliably be extrapolated. A trial designed for Grade 2 to 3 knee osteoarthritis, for example, cannot produce evidence that applies to Grade 4 cases.
The FDA’s December 2025 final guidance on Enhancing Participation in Clinical Trials encouraged sponsors to broaden eligibility criteria where scientifically justified, particularly to remove exclusions that lack clear safety rationale. This represents a meaningful regulatory shift toward more inclusive enrollment without compromising scientific rigor.
What Common Eligibility Criteria Look Like
An illustrative eligibility list for a regenerative medicine trial investigating an adipose-derived cell product for a joint condition might include the following types of requirements. These are representative examples, not taken from any single real trial, to show patients what the language typically looks like and what it means in practice.
| Criterion Type | What It Means for Patients |
|---|---|
| Age range (e.g., 40 to 75 years) | Participants outside this range cannot enroll, regardless of other factors |
| Confirmed diagnosis | A specific diagnostic code or imaging confirmation is typically required, not just a self-reported history |
| Disease severity grade (e.g., Kellgren-Lawrence Grade 2 to 3) | Patients with milder or more severe disease than the study targets may not qualify |
| Prior treatment history | Many trials require that patients have tried and not responded adequately to conservative treatments first |
| No active infection | Active infections can confound immune response data and create safety risks |
| No immunosuppressive medications | These can alter how the body responds to investigational cell products |
| No recent surgery in the target joint | Recent procedures can affect baseline measurements and complicate outcome assessment |
| Not pregnant or breastfeeding | Standard exclusion due to unknown risks to fetal and infant health |
| BMI within a defined range | Very high or very low BMI can affect both safety and outcome measures |
| Adequate organ function (lab values) | Kidney and liver function are commonly assessed; impaired function can affect how a product is processed |
Why Some Criteria Seem Strict
When patients read a list like this, the most common reaction is frustration, particularly when a single criterion they cannot change is the disqualifier. It helps to understand that the strictness of criteria usually reflects the maturity of the evidence. Phase I trials are the most restrictive because researchers know the least about safety at that stage. As more safety data accumulates across Phase II and Phase III, criteria often broaden. The more rigorous the scientific rationale for a criterion, the less likely it is to be revised. An age range that reflects the population most likely to benefit from the therapy is unlikely to change; an exclusion based on a theoretical risk that subsequent data has not supported may be removed in later phases.
Criteria You Cannot Control vs. Criteria You Might Address
Not all disqualifying criteria are permanent. Some reflect your current clinical status rather than fixed characteristics.
| Fixed Criteria (Cannot Be Changed) | Potentially Addressable Criteria |
|---|---|
| Age | Active infection (may resolve with treatment) |
| Prior diagnosis or disease history | Current medication use (may be adjustable with physician guidance) |
| Certain comorbidities | Recent procedure timing (waiting period may allow future eligibility) |
| Prior participation in conflicting trials | Uncontrolled blood pressure or blood sugar (may improve with management) |
| Specific genetic or biological markers | Scheduling conflicts that prevent completing required visits |
If a single criterion is preventing enrollment, it is worth discussing with your treating physician whether any of those factors could change over time and whether revisiting a trial at a later point makes sense.
The Enrollment Process Step by Step
The path from finding a trial to confirmed enrollment is not a single conversation. It is a structured sequence of steps, each with a distinct purpose. Understanding the full sequence in advance removes a significant amount of uncertainty.
- Find and evaluate a registered trial on ClinicalTrials.gov. Use the ClinicalTrials.gov search tool to identify trials that match your condition, location, and general profile. The guide to reading a study record explains how to interpret each section. For context on how clinical trial participation connects to the regenerative medicine research landscape, see the introduction to clinical trials for regenerative medicine.
- Review the eligibility criteria section of the study record. Read both inclusion and exclusion criteria carefully. Note any criteria you are uncertain about rather than assuming you do or do not qualify. Many patients disqualify themselves prematurely by misreading criteria.
- Bring the NCT number to your treating physician. The NCT number is the unique identifier for every registered trial. Share it with your physician and ask for their assessment of whether you appear to meet the criteria based on your medical history. Do not contact a study team before having this conversation; your physician’s perspective is essential to evaluating fit.
- Contact the study coordinator listed on the trial record. Study records on ClinicalTrials.gov include contact information for the responsible party or study coordinator. The coordinator is the appropriate first point of contact, not the principal investigator. Be prepared to describe your diagnosis and general medical history briefly.
- Complete a pre-screening call. Most trials conduct an informal telephone or videoconference pre-screening before scheduling any in-person visit. The coordinator will review key eligibility criteria with you verbally, ask about your diagnosis and treatment history, and assess whether a formal screening visit is warranted. This step saves time for both the patient and the study team.
- Schedule the formal screening visit. If the pre-screening suggests you may be eligible, the coordinator will schedule a formal in-person visit at the trial site. This visit may require travel and will take several hours in most cases.
- Attend the formal screening visit. The visit includes a full medical history review, physical examination, vital signs assessment, laboratory blood and urine tests, and any condition-specific assessments such as joint imaging for orthopedic trials. Everything done at this visit is designed to verify that you meet the protocol criteria and that participation is safe.
- Receive your screening outcome. After the screening visit, the study team reviews all results against the protocol. You may receive one of three outcomes: passed screening and eligible to enroll, screen failure meaning one or more criteria were not met, or pending results requiring additional assessment before a determination is made.
- Complete the informed consent process. If you pass screening, you will be asked to review and sign an informed consent document. This is not a formality. The informed consent process is a substantive review of the study purpose, what participation involves, risks, potential benefits, alternatives, and your right to withdraw at any time.
- Confirmed enrollment and randomization. Once consent is complete, you are formally enrolled. In blinded, randomized trials, you will be assigned to a study group (active treatment or comparator) through a randomization process that neither you nor the study team controls.
The table below summarizes all ten steps.
| Step | What Happens | Who Leads It | Approximate Timeline |
|---|---|---|---|
| 1. Find trial | Search ClinicalTrials.gov, review record | Patient | Before contact |
| 2. Review criteria | Evaluate eligibility list | Patient and physician | Before contact |
| 3. Physician consultation | Assess fit with medical history | Treating physician | Before contact |
| 4. Contact coordinator | Initial inquiry, brief history overview | Patient with coordinator | Days after decision to proceed |
| 5. Pre-screening call | Verbal eligibility review | Study coordinator | Within 1 to 2 weeks of contact |
| 6. Schedule formal screening | Set site visit | Study coordinator | 2 to 4 weeks after pre-screen |
| 7. Formal screening visit | Full clinical assessment | Study team | Half-day to full-day visit |
| 8. Screening outcome | Results reviewed against protocol | Study team | Days to 2 weeks after visit |
| 9. Informed consent | Review and sign consent document | Patient and study team | Before enrollment is confirmed |
| 10. Enrollment and randomization | Formally assigned to study group | Study team | After consent is signed |
What Happens at a Screening Visit
The formal screening visit is where eligibility is verified rather than assumed. It is worth preparing for thoroughly.
What to Bring
Arriving with the right documentation makes the visit faster and reduces the likelihood of needing a follow-up appointment to gather missing information. Plan to bring:
- A government-issued photo ID
- Your insurance card, if the visit involves any reimbursable clinical procedures
- A complete list of all current medications including dose, frequency, and prescribing physician
- Copies of prior relevant diagnostic imaging reports and films where available
- Recent laboratory results if available, particularly any that are relevant to the trial’s eligibility lab criteria
- A written list of prior surgeries with approximate dates
- Your treating physician’s name and contact information
- A written list of your questions for the study team
What the Study Team Will Do
The study team’s goal at the screening visit is to verify that every inclusion criterion is met and that no exclusion criteria are present. This typically involves a structured series of assessments conducted by clinical research staff under physician supervision:
- Full medical history review, including prior diagnoses, prior treatments, allergies, family history, and current medications
- Physical examination and vital signs
- Blood and urine laboratory draws evaluated against the protocol’s specified acceptable ranges
- Condition-specific assessments, such as joint imaging for orthopedic trials, functional assessments for neurological trials, or skin evaluations for dermatological trials
Screen Failure: What It Means and What Comes Next
Screen failure is a term that sounds more definitive than it is. It simply means that one or more eligibility criteria were not met during the formal screening evaluation. It is not a rejection of you as a patient or a judgment about whether your condition deserves treatment. Screen failure rates in clinical trials are genuinely high, particularly in Phase II and Phase III studies where criteria are more specific. In some trials, screen failure rates exceed 50 percent.
Screen failure does not affect your regular medical care. It does not close off other trials. It does not permanently disqualify you from future enrollment in the same trial if circumstances change, depending on the criterion that was not met. The appropriate next step after screen failure is a conversation with your treating physician about what the disqualifying criterion was and whether there are other appropriate trials to consider.
| Common Reason for Screen Failure | Whether It May Change Over Time |
|---|---|
| Lab value outside acceptable range | Possibly, depending on cause and treatment |
| Active infection or inflammation | Yes, typically resolves |
| Recent surgery or procedure within exclusion window | Yes, with sufficient waiting period |
| Current prohibited medication | Possibly, with physician-guided adjustment |
| Disease too mild or too severe for trial’s target population | Depends on disease progression |
| Age outside the enrolled range | No |
| Prior enrollment in a conflicting trial | Generally no |
Informed Consent: More Than a Signature
Informed consent is often described as a form, but it is more accurate to describe it as a process. The document itself is a record of a conversation that should happen before you sign anything, one in which you have had the opportunity to ask questions, receive answers, and decide freely whether to participate.
Under FDA standards, an informed consent document must cover a specific set of elements. Every participant deserves to understand each of them before agreeing to proceed.
| Informed Consent Element | What It Means in Plain Language |
|---|---|
| Purpose of the study | Why this research is being done and what question it is trying to answer |
| What participation involves | Every procedure, visit, test, and intervention that you will experience |
| Duration | How long participation lasts and how many visits are required |
| Risks and discomforts | Known and potential risks of the investigational product and study procedures |
| Potential benefits, if any | Honest statement of what benefit, if any, participants might receive (many trials cannot promise direct benefit) |
| Alternatives | What other options exist outside the trial |
| Confidentiality | How your health information will be protected and who may have access to your data |
| Voluntary nature | That participation is your choice and cannot be compelled |
| Right to withdraw | That you can leave the trial at any time without penalty or effect on your regular medical care |
| Contact information | Who to contact with questions about the study or about your rights as a participant |
Two points deserve particular emphasis. First, signing the consent document does not always mean you are immediately enrolled. In some trial designs, consent is obtained before the screening visit so that the visit itself can be conducted as part of the study protocol. In others, consent occurs after passing screening. The study coordinator will explain the sequencing for the specific trial you are considering.
Second, you can withdraw consent at any time after signing it. Withdrawal does not carry penalties. It does not affect your relationship with your own physician. It does not affect your access to approved care.
How Adipose-Derived Cell Trials Are Structured for Enrollment
Dozens of clinical trials currently registered on ClinicalTrials.gov are investigating adipose-derived cells for a range of conditions. These trials are investigational research studies. No adipose-derived cell product has received FDA approval for any disease indication. Participation in any such trial should be evaluated in consultation with a treating physician.
The enrollment structure of these trials follows the same phase-based progression as all clinical research, with criteria that typically narrow or broaden depending on where in development the product sits. For an overview of the broader research landscape, the emerging research section and the joint and orthopedic research section provide additional context.
| Phase | Typical Enrollment Size | Primary Goal | Eligibility Strictness | What Patients Should Know |
|---|---|---|---|---|
| Phase I | 20 to 100 | Safety and dose-finding | Highest: narrow criteria, often younger patients with fewer comorbidities | Focus is on safety, not effectiveness; participants contribute to foundational safety data |
| Phase II | 100 to 300 | Early effectiveness signals | Moderate: broadened slightly from Phase I but still specific | Early signal detection; results are preliminary and not proof of effectiveness |
| Phase III | 300 or more | Confirm effectiveness at scale | Structured but broader: intended to reflect the target patient population | Most rigorous evidence; results from Phase III are what FDA reviews for potential approval |
One distinction that affects eligibility in adipose-derived cell research is whether a trial is autologous (using the patient’s own tissue) or allogeneic (using a pre-manufactured donor product). Autologous trials require the patient to undergo a collection procedure to provide the starting tissue. This adds an additional eligibility layer related to the safety of that collection step: patients who cannot safely undergo a mini-liposuction procedure, for example, may not be eligible for autologous trials regardless of other criteria.
Allogeneic trials use a standardized product from a donor source and do not require the patient to undergo collection. Their eligibility criteria focus instead on immune status, medication history, and whether prior exposure to donor tissue products could affect safety or outcomes.
One regulatory note relevant to some autologous adipose trials: when adipose tissue is processed through enzymatic digestion to isolate the stromal vascular fraction (SVF), the resulting product is generally classified by the FDA as more than minimally manipulated and regulated under the Section 351 biologic pathway, requiring an Investigational New Drug application. This classification affects how those trials are structured and what regulatory approvals must be in place before enrollment can begin.
Questions to Ask Before Agreeing to Be Screened
Before you agree to schedule a formal screening visit, it is worth gathering specific information from the study coordinator. These questions protect your time, help you assess fit, and give you a clearer picture of what participation actually involves.
- What phase is this trial, and what is it primarily designed to test?
- What is the study design: is it randomized, blinded, and does it include a control or placebo group?
- What does the screening visit involve, how long does it take, and are there any costs to me for the screening itself?
- If I am enrolled, is the investigational product provided at no charge, or are there costs I would be responsible for?
- How many visits are required over the duration of the trial, and what does each involve?
- What happens to participants after the trial ends, including whether any follow-up care is provided?
- Will my treating physician be informed of my participation and receive my trial-related health data?
- How are adverse events monitored and reported, and who do I contact if I experience a problem during the trial?
- If I decide to leave the trial after enrolling, what is the process for withdrawing, and are there any consequences?
- Is there a Data Safety Monitoring Board or IRB overseeing this trial, and who can I contact as a participant advocate?
- Where will the results of this study be published, and will I be informed of the results after the study concludes?
- Are there any known conflicts of interest between the trial sponsor and the investigators that I should be aware of?
Save My Fat and Clinical Trial Eligibility
Save My Fat is a tissue banking and cryopreservation service. It is not a clinical trial operator, sponsor, or recruiter. It does not enroll patients in trials, refer patients to specific trials, or have any role in determining a patient’s eligibility for any study.
The direct question many patients have is whether banking adipose tissue through Save My Fat affects their eligibility for future clinical trials. The accurate answer is nuanced.
Banking preserves tissue at its current biological state. Whether that banked tissue is compatible with a specific future trial depends entirely on that trial’s protocol, the regulatory status of the product being studied, whether the trial accepts previously banked tissue from outside the sponsor’s manufacturing process, and what the FDA’s current guidance requires for starting material in that product category. Most trials currently recruiting for autologous adipose-derived cell therapies require fresh collection conducted as part of the trial itself, not tissue banked independently beforehand. Future trials may be designed differently as the science and regulatory landscape evolve.
Banking does not guarantee eligibility for any trial. It preserves optionality: the tissue exists, it is viable, and it is available if a future legitimate medical opportunity arises that is compatible with previously banked material. For a complete description of what the banking process involves and what is preserved, see the complete guide to adipose tissue banking and the explanation of how stem cell banking works.
Any future use of banked tissue depends on the evolving science, FDA regulatory decisions at the time of use, the patient’s clinical situation, their physician’s guidance, and the availability of FDA-regulated pathways. For patients who are also exploring access pathways outside of formal trials, the guide to Expanded Access programs describes the compassionate use framework in detail.
Frequently Asked Questions
What are inclusion criteria and exclusion criteria in a clinical trial?
Inclusion criteria are the specific characteristics a participant must have in order to be eligible for a trial, such as a confirmed diagnosis, age range, or disease severity. Exclusion criteria are characteristics that prevent participation even when inclusion criteria are met, such as active infections, recent surgeries, or specific medications. Both sets of criteria are defined in the trial protocol, reviewed by an Institutional Review Board, and published in the study record on ClinicalTrials.gov. The definitions are drawn from the ClinicalTrials.gov Glossary.
Why do clinical trials have strict eligibility rules?
Eligibility criteria exist for three main reasons: to protect participant safety by excluding people who face disproportionate risks from the intervention, to protect data integrity by ensuring the study population is homogeneous enough to produce interpretable results, and to ensure scientific validity so that results apply to the intended patient population. The strictness of criteria typically reflects how early in development the product is. Phase I trials are the most restrictive because the least is known about safety. Criteria tend to broaden as the evidence base grows.
What happens during the formal screening process?
The formal screening visit is a structured clinical evaluation at the trial site that verifies you meet all eligibility criteria. It typically includes a full medical history review, physical examination, vital signs, laboratory blood and urine tests, and any condition-specific assessments required by the protocol such as imaging. Results are reviewed against the protocol criteria, and you receive an outcome of eligible, screen failure, or pending. The visit usually takes several hours and requires advance preparation.
What should I bring to a screening visit?
Bring a photo ID, current medications list with doses, copies of relevant diagnostic imaging reports, recent laboratory results if available, a written list of prior surgeries with approximate dates, your treating physician’s contact information, and a written list of questions for the study team. Arriving without relevant medical records is one of the most common reasons a screening visit needs to be repeated, so thorough preparation saves time.
Can I be excluded from a trial even if I think I meet all the criteria?
Yes. Meeting the written criteria as described in the study record is a necessary condition for enrollment, not a sufficient one. The formal screening visit evaluates criteria that cannot be assessed through self-report, including laboratory values, imaging findings, and physical examination results. A criterion that appears to be met on paper may not be met after objective clinical measurement. Screen failure rates in many trials exceed 50 percent, so a screen failure outcome is common and not a reflection on the patient.
What is the difference between pre-screening and formal screening?
Pre-screening is an informal review, usually conducted by phone or video with the study coordinator, in which key eligibility factors are reviewed verbally before committing to an in-person visit. Its purpose is to save both the patient and the study team time by identifying obvious disqualifiers early. Formal screening is the clinical evaluation at the trial site that generates the objective data the study team uses to make a final eligibility determination. Pre-screening is not binding; formal screening produces a definitive eligibility outcome.
Can I enroll in more than one clinical trial at the same time?
In most cases, no. Many trial protocols include an exclusion criterion that disqualifies participants who are currently enrolled in another interventional clinical study, because simultaneous participation could confound the data and create safety risks from multiple investigational exposures. Some observational studies (which involve no investigational intervention) may not carry this restriction, but interventional trials almost universally do. Always disclose any current trial enrollment to the study coordinator at the pre-screening stage.
Are there adipose-derived cell trials I can search for today?
Yes. ClinicalTrials.gov maintains a public registry of all registered human studies, including trials investigating adipose-derived cells for various conditions. Searching for terms like “adipose-derived stem cells” or “adipose stromal cells” in the condition you are interested in will return registered studies along with their eligibility criteria, contact information, and recruitment status. Registration on ClinicalTrials.gov is a transparency requirement; it does not mean a product is proven safe or effective, and it does not mean patients should seek enrollment without physician guidance. The emerging research overview provides context on the research landscape.
Does banking tissue with Save My Fat help with trial eligibility?
Not directly. Save My Fat banks adipose tissue for potential future use in FDA-regulated pathways. Whether banked tissue is compatible with a specific future trial depends entirely on that trial’s protocol, the regulatory classification of the product being studied, and whether the sponsor’s manufacturing process accepts previously banked material from outside sources. Most currently active autologous adipose-derived cell trials require fresh collection conducted as part of the trial protocol. Banking preserves tissue at its current biological state for a future that may include compatible opportunities. It does not create eligibility for any existing or future trial.
What does screen failure mean and what should I do if it happens?
Screen failure means that one or more eligibility criteria were not met during the formal screening evaluation. It is common, it is not a judgment on the patient’s situation, and it does not affect ongoing medical care. After a screen failure, the appropriate next step is to discuss the disqualifying criterion with your treating physician, understand whether it is fixed or potentially changeable, and explore whether other appropriate trials are available. ClinicalTrials.gov lists thousands of active studies, and a screen failure in one trial does not affect eligibility for others.
Key Takeaways
- Eligibility criteria serve a scientific and protective purpose. They exist to protect participants from unknown risks and to ensure that trial results are reliable and apply to the intended population. They are not arbitrary.
- The enrollment process has multiple stages. Finding a trial, reviewing criteria, consulting your physician, pre-screening, formal screening, informed consent, and enrollment are distinct sequential steps. Meeting the written criteria is not the same as being accepted.
- Informed consent is a process, not just a signature. Participants must be given the opportunity to ask questions and must understand the purpose, risks, procedures, and voluntary nature of the study before signing.
- Screen failure is normal and does not close off future options. Screen failure rates in many trials exceed 50 percent. One screen failure does not affect medical care or eligibility for other studies.
- Adipose-derived cell trials follow the same phase-based structure as all research. Phase I trials prioritize safety with tight criteria; Phase III trials confirm effectiveness in larger, more representative populations. All remain investigational. No adipose-derived cell product is FDA-approved.
- Save My Fat is a tissue banking service only. It does not enroll patients in trials, determine eligibility, or provide investigational therapies. Banking preserves tissue for potential future use in FDA-regulated pathways but does not guarantee access to any trial or therapy.
- Always involve your treating physician. No decision about clinical trial enrollment should be made based on this educational article or on clinic marketing alone. Your physician’s knowledge of your full medical history is essential to evaluating fit.
Learn More
The following resources provide additional context for patients researching clinical trials and the regenerative medicine landscape.
Save My Fat helps individuals preserve their own adipose tissue through validated cryopreservation protocols for potential future opportunities that may arise as regenerative medicine science and FDA regulations evolve. Banking tissue does not guarantee eligibility, access, or clinical benefit from any future therapy, clinical trial, or medical program. Save My Fat does not provide FDA-approved treatments or cures.
- What Are Clinical Trials for Regenerative Medicine? covers how clinical trials work and how banked adipose tissue fits into the research landscape.
- Adipose Tissue Banking: A Complete Guide explains the full banking process, cryopreservation protocols, and what preservation means for future access.
- Emerging Research provides an overview of the conditions and applications where adipose-derived cell research is most active.
- Joint and Orthopedic Applications covers the musculoskeletal research landscape in more depth.
- Expanded Access Programs: How Patients Can Legally Access Investigational Therapies explains the compassionate use framework for patients who cannot enroll in a trial.
- How Stem Cell Banking Works describes the step-by-step banking process.
- For Patients provides an overview of what Save My Fat offers for patients exploring their options.
- For Providers covers how physicians can offer tissue banking to their patients.
The Reagan-Udall Expanded Access Navigator is a free, independent resource for patients and physicians navigating expanded access pathways. It is not affiliated with Save My Fat.
This article is for educational purposes only and does not constitute medical advice. Please consult your licensed healthcare provider regarding all medical decisions.
Last Updated: April 5, 2026
About the author: Oscar Tellez is the founder and CEO of Save My Fat. He holds a Bachelor of Science in Exercise Science and Health Promotion from Florida Atlantic University. He has spent more than a decade in the regenerative medicine industry across product distribution, laboratory and vendor relationships, and provider training. He is not a licensed clinician, and this article is educational, not medical advice.
Related guide: adipose stem cell trials.
