Estar Technologies Ltd
FDA issued a warning letter to Estar Technologies Ltd (Holon, Israel) on Apr 22, 2026, citing 21 CFR 807.81. Subject: Investigational Device Exemptions (IDE), Premarket Approval Application (PMA) Adulterated Device.
From the letter: “your devices are adulterated under section 501(f)(1)(B) of the Act, 21 U.S.C. § 351(f)(1)(B), because your firm does not have approved applications for premarket approval (PMA) in effect pursuant to section 515(a) of the Act, 21 U.S.C. §…”
At a glance
What a reviewer notes before reading: findings, citations, the response deadline and what the letter warns of.
- Violations
- 3 findings · 2 issue types
- Cited
- 21 CFR 807.81
- Response due
- Not stated in the letter
- FDA asks for
- 6 actions
- Named as possible actions
- Seizure, injunction, civil money penalties
- Issued by
- Center for Biologics Evaluation and Research
- Published status
- No close-out recorded
AI assisted findings
Model-assisted reading of each issue. Open one to see the FDA text it comes from, and check it against the full letter.
01Registration, listing & premarketDevices are adulterated because no PMA or IDE applications are in effect.
your devices are adulterated under section 501(f)(1)(B) of the Act, 21 U.S.C. § 351(f)(1)(B), because your firm does not have approved applications for premarket approval (PMA) in effect pursuant to section 515(a) of the Act, 21 U.S.C. § 360e(a), or approved applications for an investigational device exemption (IDE) under section 520(g) of the Act, 21 U.S.C. § 360j(g).
02Registration, listing & premarket · 21 CFR 807.81(a)Devices are misbranded because the firm did not notify FDA of intent to introduce them into commercial distribution.
Your devices are also misbranded under section 502(o) of the Act, 21 U.S.C. § 352(o), because your firm did not notify the agency of its intent to introduce your devices into commercial distribution, as required by section 510(k) of the Act, 21 U.S.C. § 360(k), and 21 CFR 807.81(a).
03Labeling, claims & marketing · 21 CFR 807.81(a)(3)The firm promoted the cleared PRP kit for major new intended uses beyond its cleared indication.
These represent major changes or modifications to the intended uses for this device and are changes or modifications that could significantly affect its safety or effectiveness. Therefore, premarket notification for this device is required. See 21 CFR 807.81(a)(3).
What FDA requested
- Cease activities resulting in misbranding or adulteration of the devices.
- Notify FDA in writing of specific steps taken to address violations.
- Explain how the firm plans to prevent these or similar violations.
- Include documentation of corrections and corrective actions taken.
- Provide a timetable for implementation of planned corrections.
- State reasons for delay if corrections cannot be completed within fifteen business days.
FDA Warning Letter
18 paragraphs · 2 sectionsText as published on FDA.gov, retrieved Oct 30, 2026. Layout added for reading; the wording is FDA’s. View on FDA.gov (opens in a new tab)
1Introduction
6 paragraphs
The United States Food and Drug Administration (FDA) has learned that your firm is offering for sale the Tropocells® PRP kit, Tropocells® PRF kit, Tropocells® TRS kit, Tropocells® PRFM kit, TropoVisc™ kit, Tropokine™ kit, and Cellenis® PRP kit (hereafter, “your devices”) in the United States without marketing clearance or approval, in violation of the Federal Food, Drug, and Cosmetic Act (the Act). Under section 201(h) of the Act, 21 U.S.C. § 321(h), your devices are intended for use in the diagnosis of disease or other conditions or in the cure, mitigation, treatment, or prevention of disease, or are intended to affect the structure or any function of the body.
Based on information and records reviewed by FDA, including your websites at https://www.tropocells.com and https://estar-medical.com/ (last visited April 2026), your devices are adulterated under section 501(f)(1)(B) of the Act, 21 U.S.C. § 351(f)(1)(B), because your firm does not have approved applications for premarket approval (PMA) in effect pursuant to section 515(a) of the Act, 21 U.S.C. § 360e(a), or approved applications for an investigational device exemption (IDE) under section 520(g) of the Act, 21 U.S.C. § 360j(g). Your introduction or delivery for introduction of your devices into interstate commerce, or the causing thereof is a prohibited act under section 301(a) of the Act, 21 U.S.C. § 331(a). Your devices are also misbranded under section 502(o) of the Act, 21 U.S.C. § 352(o), because your firm did not notify the agency of its intent to introduce your devices into commercial distribution, as required by section 510(k) of the Act, 21 U.S.C. § 360(k), and 21 CFR 807.81(a).
Of note, the TropoCells® PRP kit was cleared under premarket notification (510(k)) submission number BK110035 with the following indication, “safe and rapid preparation of autologous platelet-rich plasma (PRP) from a small sample of blood at the patient point of care. The PRP is mixed with autograft and/or allograft bone prior to application to a bony defect for improving handling characteristics.” However, you include statements such as the following on your website, https://www.tropocells.com, regarding the uses of the Tropocells® PRP kit:
“Tropocells® PRP is the ideal autologous technology for the healing of: musculoskeletal injuries, joint and osteoarthritis treatment, sports injuries, wound healing, ophthalmology, dentistry and oral surgery, and post-surgical recovery.”
These represent major changes or modifications to the intended uses for this device and are changes or modifications that could significantly affect its safety or effectiveness. Therefore, premarket notification for this device is required. See 21 CFR 807.81(a)(3).
For a device requiring premarket approval, the notification required by section 510(k) is deemed satisfied when a PMA is pending before the FDA. 21 C.F.R. § 807.81(b). The kind of information that you need to submit in order to obtain approval or clearance for your devices is described on the Internet at http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/HowtoMarketYourDevice/default.htm. FDA will evaluate the information that your firm submits and decide whether the products may be legally marketed.
2Conclusion
4 paragraphs
Estar Technologies Ltd. should cease any activities that result in the misbranding or adulteration of the Tropocells® PRP kit, Tropocells® PRF kit, Tropocells® TRS kit, Tropocells® PRFM kit, TropoVisc™ kit, Tropokine™ kit, and Cellenis® PRP kit, such as the commercial distribution of the devices for the uses discussed above.
Your firm should take prompt action to address any violations identified in this letter. Failure to promptly adequately address this matter may result in regulatory action being initiated by the FDA without further notice. These actions include, but are not limited to, seizure, injunction, and civil money penalties.
Please notify our office in writing within fifteen business days from the date you receive this letter of the specific steps your firm has taken to address the noted violations, as well as an explanation of how your firm plans to prevent these violations, or similar violations, from occurring again. Include documentation of the corrections and/or corrective actionsyour firm has taken. If your firm’s planned corrections and/or corrective actions will occur over time, please include a timetable for implementation of those activities. If corrections and/or corrective actions cannot be completed within fifteen business days, state the reason for the delay and the time within which these activities will be completed. Your firm’s response should be comprehensive and address any violations included in this Warning Letter. If you believe that your devices are not in violation of the Act, include your reasoning and any supporting information for our consideration as part of your response.
Send your electronic response and any questions regarding this letter to CBER’s Office of Compliance and Biologics Quality, Division of Case Management at CBERDCMRecommendations@fda.hhs.gov.
Citations and trends
Each 21 CFR section, ISO 13485 clause and issue type in this letter, how often it appears across all letters, and its trend by the year FDA issued the letters. 2026 runs to Nov 3, 2026, compared with the same dates last year. Select a row or a bar to see those letters in Letters. As cited in this historical letter, not a statement of current requirements.
Regulations
Issue types
Record details
- Issuing center
- Center for Biologics Evaluation and Research
- Issuing office
- Center for Biologics Evaluation and Research
- Location
- Holon, Israel
- Letter posted date
- May 12, 2026
- Letter issue date
- Apr 22, 2026
- Addressed to
- Chief Executive Officer and Founder
- Inspection dates
- Not recorded
- Response window
- Not verified in this snapshot. Consult the original letter.
- Record length
- 803 words · 0 recorded redactions
- Published status
- No published close-out
- FDA reference
- CBER 26-716831
- Original letter
- View on FDA.gov (opens in a new tab)
- Dataset last checked
- Nov 11, 2026 · How this is built
A response window is not a calculated due date. Source excerpts are selected passages. Finding interpretations and categories are model-assisted. Verify the original letter before relying on a finding.