The FDA issued a warning letter to ExThera Medical Corporation on February 6, 2026, citing serious regulatory violations related to the promotion and distribution of its Seraph 100 Microbind Affinity Blood Filter without proper premarket approval. The enforcement action represents a significant setback for the company and signals heightened FDA scrutiny over unapproved device marketing practices in the medical device industry.
This article examines the regulatory violations that triggered the FDA warning letter, the enforcement landscape surrounding investigational devices, the operational and financial consequences for ExThera and similar companies, and the compliance expectations that medical device manufacturers must meet to avoid similar enforcement actions.
FDA Authority and Device Classification: The FDA regulates medical devices under the Federal Food, Drug, and Cosmetic Act (FD&C Act). Devices like the Seraph 100 require either premarket approval (PMA), a 510(k) clearance, or an investigational device exemption (IDE) before marketing. The Seraph 100 was initially granted an Emergency Use Authorization (EUA) in April 2020 for COVID-19 treatment but lacked full PMA approval for broader clinical applications.
Investigational Device Requirements: Under 21 CFR 812.5(b) and 21 CFR 812.7, investigational devices must comply with strict labeling regulations prohibiting claims of safety and effectiveness. The FDA’s Office of Bioresearch Monitoring Inspectorate (OBMI) enforces these requirements by monitoring clinical trial compliance and protecting research subjects from hazards and risks.
Enforcement Authority: The FDA possesses broad authority to issue warning letters, conduct inspections, and revoke authorizations when manufacturers violate device regulations. The agency can determine devices as adulterated or misbranded under section 501(f)(1)(B) of the FD&C Act when lacking approved applications for their intended uses.
Why This Happened
Aggressive Marketing Without Approval: ExThera’s Chief Medical Officer, Lakhmir Chawla, M.D., made public statements claiming the Seraph 100 was approved in the United States and safe and effective for treating COVID-19, long COVID, cancer, chronic viremia, and Lyme disease. These claims violated FDA regulations governing investigational device promotion and extended far beyond the device’s limited EUA scope.
Prior FDA Warnings Ignored: The FDA had previously communicated concerns to ExThera through an It Has Come to Our Attention (IHCTOA) letter on July 17, 2024, and during interactive IDE supplement reviews in July 2024, specifically requesting removal of promotional claims. ExThera’s failure to comply with these warnings escalated enforcement action.
Broader Compliance Failures: Beyond marketing violations, the inspection revealed that ExThera distributed devices for compassionate use without obtaining FDA approval, failed to monitor clinical investigations properly, and did not verify informed consent documentation for enrolled subjects.
Impact on The Company
Financial and Operational Consequences: The warning letter and subsequent Emergency Use Authorization revocation (effective November 24, 2025) effectively halted ExThera’s ability to legally distribute the Seraph 100 in the United States. This eliminates revenue streams and forces operational restructuring.
Compliance Obligations and Enforcement Exposure:
- ExThera must cease all activities resulting in misbranding or adulteration of the Seraph 100
- The company faces potential civil and criminal penalties for past violations
- Clinical trial subjects may pursue liability claims for inadequate informed consent
- Institutional review boards and clinical sites may face scrutiny for their role in unauthorized device use
- Healthcare providers who used the device off-label may face reputational and legal exposure
Company executives and clinical officers bear personal responsibility for regulatory violations. The warning letter specifically names Dr. Chawla’s statements, creating potential liability for individuals involved in marketing decisions.
Enforcement Direction
The FDA’s enforcement action signals intensified scrutiny of investigational device marketing and off-label promotion. Medical device companies are receiving a clear message that aggressive marketing claims without premarket approval will trigger warning letters, inspections, and authorization revocations. The agency’s focus on website content, public statements by executives, and compassionate use pathway compliance demonstrates that the FDA monitors multiple communication channels and expects strict adherence to investigational device regulations.
FDA wants to ensure that device manufacturers are reviewing marketing materials, restricting public statements by clinical officers, and implementing stricter controls over promotional activities. Clinical sites and healthcare providers need to become more cautious about using investigational devices, particularly when companies make unapproved claims.
Compliance Expectations
Premarket Approval Requirements: Medical device manufacturers must obtain appropriate premarket approval (PMA, 510(k), or IDE) before making any marketing claims or distributing devices for clinical use. The Seraph 100’s lack of full PMA approval meant that all promotional activities claiming safety and effectiveness violated FDA regulations.
Investigational Device Labeling Controls: Companies sponsoring investigational devices must strictly comply with 21 CFR 812.5(b) and 812.7, which prohibit claims of safety and effectiveness in labeling and promotional materials. Website content, FAQ pages, and public statements by company officials must avoid any language implying device approval or proven safety profiles.
Compassionate Use Pathway Compliance: When distributing devices through compassionate use, manufacturers must obtain FDA approval before shipping devices. Documentation of informed consent and proper monitoring of device use are mandatory. ExThera’s failure to follow these procedures violated federal regulations and exposed patients to undetermined risks.
Clinical Trial Monitoring: Sponsors of investigational device studies must properly monitor investigations, verify informed consent, and maintain detailed records. The FDA’s OBMI inspections specifically assess these compliance areas, and failures result in warning letters and potential enforcement action.
Best Practices for Companies
Immediate Compliance Actions:
- Audit all marketing materials, website content, and public statements for unapproved claims of safety, effectiveness, or approval status
- Remove any language from websites, FAQ sections, and promotional materials that implies device approval or established safety profiles
- Implement a centralized review process requiring legal and regulatory approval before any public statements by executives or clinical officers
- Cease distribution of investigational devices except through properly approved pathways with documented FDA authorization
- Establish a compliance hotline and internal reporting mechanism for employees to flag potential marketing violations
Clinical Trial Governance:
- Implement robust monitoring protocols for all investigational device studies with documented oversight and verification procedures
- Maintain comprehensive informed consent documentation for every enrolled subject with evidence of signature and comprehension
- Establish independent data safety monitoring boards to oversee investigational device studies
- Conduct quarterly compliance audits of clinical trial sites to verify adherence to investigational plans
- Train all personnel involved in clinical investigations on FDA regulations and company compliance policies
Continuous Improvement and Risk Mitigation:
- Establish a regulatory intelligence function to monitor FDA guidance documents, warning letters to competitors, and enforcement trends
- Conduct annual risk assessments identifying potential compliance gaps in marketing, clinical trial management, and device distribution
- Implement a document control system ensuring all promotional materials are dated, reviewed, and archived for FDA inspection readiness
- Develop contingency plans for responding to FDA inquiries, warning letters, and inspection findings with designated response teams and timelines
- Create a culture of compliance through executive leadership commitment, employee training, and accountability mechanisms for violations
The ExThera case demonstrates that FDA enforcement extends beyond manufacturing quality to encompass marketing practices, executive communications, and clinical trial governance. Device manufacturers must recognize that aggressive promotion of investigational devices without approval triggers enforcement action regardless of company size or market position.
The revocation of the Seraph 100’s Emergency Use Authorization and the warning letter to ExThera establish a regulatory precedent for enforcement against unapproved device marketing. Medical device companies operating in the investigational space must implement rigorous compliance controls, restrict promotional activities to approved claims, and maintain meticulous documentation of all device distribution and clinical use. The financial and reputational consequences of regulatory violations underscore the critical importance of compliance-first organizational cultures in the medical device industry.
FAQ
1. What violations did the FDA identify in the warning letter to ExThera?
Ans: The FDA cited ExThera for multiple violations including promoting the Seraph 100 as FDA-approved without premarket approval, making unapproved claims of safety and effectiveness for uses including cancer treatment, distributing devices through compassionate use without FDA authorization, failing to properly monitor clinical investigations, and not verifying informed consent documentation for research subjects.
2. What is the difference between an Emergency Use Authorization and premarket approval?
Ans: An Emergency Use Authorization (EUA) permits limited distribution of an unapproved device during public health emergencies. It is temporary and does not constitute full premarket approval. Premarket approval (PMA) requires comprehensive clinical data demonstrating safety and effectiveness for specific intended uses. The Seraph 100 had an EUA for COVID-19 but lacked PMA for broader applications like cancer treatment.
3. Can healthcare providers still use the Seraph 100 after the EUA revocation?
Ans: No. The FDA revoked the Emergency Use Authorization effective November 24, 2025, meaning the Seraph 100 can no longer be legally distributed or used in the United States. Any use after the revocation date would constitute distribution of an unapproved device and violate federal law.
4. What are the consequences for hospitals and clinics that used the Seraph 100 off-label?
Ans: Healthcare providers who used the device based on ExThera’s unapproved claims may face regulatory scrutiny from state medical boards, potential liability claims from patients, and reputational damage. Institutional review boards may also face questions about their oversight of investigational device use at their facilities.
5. How should medical device companies respond to FDA warning letters?
Ans: Companies must respond within 15 business days with a detailed explanation of corrective actions taken to address each violation cited. The response should include evidence of compliance such as revised marketing materials, updated policies, employee training records, and implementation timelines. Failure to respond adequately or continue violations can result in additional enforcement action including seizure or injunction.
6. What regulatory pathway should ExThera pursue to obtain approval for the Seraph 100?
Ans: ExThera would need to submit a comprehensive Premarket Approval (PMA) application demonstrating safety and effectiveness for each intended use through well-controlled clinical trials. Alternatively, if the device qualifies as substantially equivalent to a predicate device, a 510(k) submission might be appropriate. The company must work closely with FDA through pre-submission meetings to determine the appropriate pathway.
7. Are other medical device companies at risk of similar FDA enforcement?
Ans: Yes. Any investigational device manufacturer making unapproved claims of safety or effectiveness, promoting devices beyond their authorized scope, or failing to comply with IDE regulations faces similar enforcement risk. The ExThera case establishes a regulatory precedent that the FDA actively monitors website content, executive statements, and marketing materials for compliance violations.