Paid Clinical Trials: How Compensation Works, What to Expect, and Key Regulatory Protections

Paid clinical trials represent a structured pathway for individuals to contribute to medical research while receiving compensation for their participation. In the United States, clinical trials may involve payment or reimbursement for participation, but what participants receive varies substantially by study and protocol. 1 The compensation structure, eligibility requirements, and study procedures are detailed in informed consent documents that are reviewed and approved by Institutional Review Boards (IRBs) before enrollment begins. Understanding how these trials operate, what types of studies are currently recruiting, and what regulatory protections exist is essential for anyone considering participation.

Types of Paid Clinical Trials Currently Recruiting

A diverse portfolio of paid clinical trials is actively recruiting participants across the United States. Studies span multiple therapeutic areas including cardiovascular disease, diabetes, respiratory conditions, rheumatological disorders, and rare genetic syndromes. The Evaluation of the Fully Closed Loop Omnipod System in Type 2 Diabetes is recruiting at 10 sites in 9 states, with enrollment continuing until September 23, 2027. 2 This multi-center, 26-week randomized controlled trial assesses the safety and efficacy of an automated insulin delivery system in adults using insulin therapy. Similarly, the BRANCH-HF study evaluates PF-07328948 in adults with heart failure across 25 sites in 8 states, with participants involved for approximately 48 weeks and 15 clinic visits. 2

Respiratory disease trials are also actively recruiting. A Study to Evaluate Solrikitug in Participants With COPD (ZION) is recruiting at 83 sites across 24 states, representing one of the largest ongoing studies in the research network, with approximately 171 eligible participants being randomized across 60 to 90 sites. 2 Rare disease research is similarly robust, as exemplified by the DiSCOVER Celiprolol trial, which targets individuals 15 years of age or older with Vascular Ehlers-Danlos Syndrome (VEDS) caused by a COL3A1 mutation. 2 This trial allows participation from home with compensation for completed telemedicine and in-home visits, plus a full vascular screening and genetic test confirmation at no cost to participants. Gastrointestinal disorders are represented through studies of targeted therapies for moderate to severe Crohn's disease, recruiting at 64 sites in 26 states with an enrollment deadline of August 1, 2028. 2

Eligibility Criteria and Participant Requirements

Clinical trial eligibility varies significantly based on study objectives and the populations being investigated. Many trials restrict participation to individuals within specific age ranges. For example, the BRANCH-HF heart failure study requires participants aged 18 to less than 80 years with clinically confirmed heart failure diagnosis for at least 3 months prior to screening. 2 Other studies target narrower age windows or specific demographic groups. The T1D Pregnancy and Me study recruits pregnant individuals with Type 1 diabetes, recognizing that pregnancy management with diabetes represents a critical clinical area associated with elevated maternal and fetal complications. 2

Disease-specific criteria are central to study participation. Participants in the ZION COPD study must be at least 40 years of age and no older than 75 years, with a documented COPD diagnosis for at least 12 months prior to screening as defined by GOLD Guidelines 2023, with elevated blood eosinophils at screening. 2 The CAPTIVATE study evaluating DNTH103 in chronic inflammatory demyelinating polyneuropathy requires confirmed CIDP diagnosis with a CIDP Disease Activity Status score of 3 or greater, weight between 40 and 120 kilograms, and neurological stability. 2 Healthy volunteer studies represent another category, such as the study of LY4065967, which requires overtly healthy participants with normal clinical laboratory results, normal electrocardiogram findings, and body mass index within 18.0 to 35.0 kilograms per square meter. 2 Many trials explicitly exclude participants with concurrent medications that may interact with study drugs or exclude those with certain comorbidities that would confound results.

Study Designs and Duration

Paid clinical trials employ diverse study designs tailored to research questions and therapeutic areas. Randomized controlled trials (RCTs) represent a common design in drug efficacy research. The Omnipod Type 2 Diabetes study is structured as a 26-week RCT with a primary endpoint at 15 weeks and secondary analysis at 26 weeks, followed by an extension phase where the control group crosses over to the intervention. 2 Double-blind, placebo-controlled designs are standard in early-phase drug development, exemplified by the ZION COPD study, a 12-week randomized, double-blind, placebo-controlled trial evaluating solrikitug at two dose levels versus placebo, with a post-treatment follow-up period of 16 weeks. 2

Study duration ranges from brief Phase 1 investigations to lengthy observational and extension protocols. Phase 1 studies typically assess safety and pharmacokinetics in healthy volunteers or small patient populations. A Study to Learn How a Single Dose of PF-08057418 is Tolerated involves healthy adults dosed once weekly for 5 weeks with clinic stays and follow-up visits totaling approximately 13 weeks from screening to final visit. 2 Longer trials accommodate multiple visits and extended treatment periods. The CAPTIVATE study for CIDP includes an open-label period of up to 13 weeks, a randomized placebo-controlled double-blind treatment period of up to 52 weeks, an optional open-label extension of up to 104 weeks, and a 40-week safety follow-up, representing potential participation lasting over 2 years. 2 Some trials include extension phases to allow continued access to investigational treatments after initial efficacy assessment. The Crohn's disease targeted therapies study involves approximately 540 participants enrolled worldwide at approximately 300 sites, with treatments including risankizumab, trosunilimab, lutikizumab, and ABBV-8736 administered as injections or infusions. 2

Compensation Models and Visit Structure

Compensation for clinical trial participation typically reflects the burden placed on participants, including time commitment, number of visits, and procedures required. The DiSCOVER Celiprolol trial explicitly states that participants can receive compensation for completed telemedicine and in-home visits, recognizing the convenience advantage of remote participation. 2 The specific dollar amounts and payment schedules are detailed in study-specific protocols and informed consent documents reviewed by IRBs. Most trials include a combination of study visits: in-person clinic visits for procedures such as blood draws, imaging, or injections, and remote visits conducted via telemedicine or telephone for follow-up assessments and symptom monitoring. The BRANCH-HF heart failure study includes approximately 15 clinic visits over 48 weeks, with roughly 5 visits potentially conducted at home by phone and 10 visits at study sites. 2 The PAH Exercise Study provides complimentary sotatercept therapy plus a tailored progressive home exercise program with wrist-worn fitness tracking and oxygen saturation monitoring across 26 weeks. 2

Compensation models also address the provision of study medications or devices at no cost to participants. Participants in the DiSCOVER trial receive a full vascular screening and genetic test confirmation at no cost, reducing barriers to participation for individuals with rare genetic conditions. 2 Some studies provide access to investigational medications before FDA approval. The DiSCOVER trial offers an early access program where, at the end of the treatment testing phase, participants have access to celiprolol before it is approved in the United States. 2 These structures reflect efforts to mitigate financial burden while ensuring informed participation.

Regulatory Protections and Informed Consent

All US-sponsored clinical research involving human participants must comply with federal regulations designed to protect subjects from harm and ensure ethical conduct. Most US-based clinical research is required to have an Institutional Review Board (IRB) review to protect participants, including oversight of how payments and reimbursements are handled in the consent process. 1 IRBs evaluate the scientific merit of studies, assess risks and benefits to participants, and ensure informed consent procedures are adequate. The revised Common Rule (45 CFR 46) establishes baseline protections for human subjects in research, including informed consent requirements that IRBs must verify are met. Informed consent documents for clinical trials must describe participant compensation (if any), and the IRB-approved consent process is intended to protect subjects from undue influence related to payment amounts or promises. 1 The Food and Drug Administration (FDA) regulates certain aspects of clinical investigations under the Federal Food, Drug, and Cosmetic Act and implementing regulations, particularly for studies involving investigational drugs or biologics. 3

ClinicalTrials.gov, maintained by the US National Library of Medicine (NLM), serves as a publicly accessible registry listing information about many clinical studies, including locations and contact details. 4 This resource enables prospective participants to locate studies aligned with their conditions and geographic proximity. The National Institutes of Health (NIH) supports and funds many clinical trials through its institutes and programs, with funded trials commonly registered and reported in public registries to promote transparency. 5 Guidance from the HHS Office for Human Research Protections (OHRP) further clarifies informed consent requirements, specifying consent elements that IRBs must address to ensure participants understand their rights, the study procedures, risks, benefits, and alternatives. 6

Key Considerations Before Enrolling in Paid Clinical Trials

Prospective participants should evaluate several factors before committing to trial enrollment. Understanding study duration and visit frequency is essential, as some trials require substantial time commitment across months or years. Assessing whether eligibility criteria align with personal health status and medication regimen prevents enrollment in studies for which participants do not qualify. Many trials require stable baseline conditions; for example, the ZION COPD study specifies participants must be on stable background therapy for COPD for longer than 90 days and will continue throughout the trial period. 2 Reviewing inclusion and exclusion criteria carefully determines whether participation is feasible. Participants should understand that compensation does not eliminate all financial or opportunity costs; time away from work or family, travel expenses not covered by study reimbursement, and potential side effects from investigational medications represent real considerations. Informed consent documents, available at study sites or through study contact information, detail specific risks, benefits, study procedures, and compensation amounts. These documents should be read thoroughly before providing consent. Questions about study participation can be directed to study coordinators whose contact information is typically provided in recruitment materials and on ClinicalTrials.gov.

Finding and Evaluating Paid Clinical Trial Opportunities

Multiple pathways exist for identifying paid clinical trials matching individual health profiles and geographic locations. ClinicalTrials.gov provides a publicly accessible registry of clinical studies, including details like study purpose and recruitment/contact information. 4 Participants can search by condition, location, recruitment status, and trial phase to identify relevant opportunities. Healthcare providers often have information about clinical trials recruiting in their patient populations and may refer interested patients directly to research coordinators. Some research institutions maintain their own recruitment websites listing active studies. Dedicated clinical trial recruitment platforms aggregate study listings from multiple sources, streamlining the search process for participants. Community health organizations focused on specific diseases frequently maintain lists of relevant trials and may provide educational resources about participation. When evaluating trial opportunities, participants should verify that studies are registered on ClinicalTrials.gov, confirm IRB oversight and regulatory compliance, assess whether compensation aligns with time commitment and procedures involved, and ensure study sites are conveniently located or offer remote participation options where applicable. Consulting with personal physicians before enrolling in any clinical trial is advisable to ensure the study does not conflict with existing medical conditions or medications.

Sources

1. HHS Office for Human Research Protections (OHRP) - Informed Consent and Compensation Guidelines for Clinical Research
2. Paid Clinical Trials Database and Research Portal - Active Clinical Trial Listings and Study Protocols
3. U.S. Food and Drug Administration (FDA) - Investigational New Drug (IND) Application Guidance and Regulatory Framework
4. ClinicalTrials.gov (National Library of Medicine, NIH) - Public Registry of Clinical Studies
5. National Institutes of Health (NIH) - Clinical Research, Trials, and You Resources
6. HHS Office for Human Research Protections (OHRP) - Revised Common Rule and Human Subjects Research Protections (45 CFR 46)