WARNING LETTER
Onkos Surgical, Inc.
MARCS-CMS 712573 —
July 21, 2025
Delivery Method:
VIA Electronic Mail
Product:
Medical Devices
Recipient:
Recipient Name
Patrick J. Treacy
Recipient Title
President and CEO
Onkos Surgical, Inc.
77 E Halsey Rd
Parsippany
,
NJ
07054
United States
ptreacy@onkossurgical.com
Issuing Office:
Center for Devices and Radiological Health
United States
WARNING LETTER
CMS # 712573
July 21, 2025
Dear Mr. Patrick J. Treacy:
During an inspection of your firm located in Parsippany, NJ from February 4, 2025 through April 4, 2025, an investigator (or investigators) from the United States Food and Drug Administration (FDA) determined that your firm is a specification developer of the ELEOS Limb Salvage System indicated for use in total hip and knee arthroplasty for reduction or relief of pain and/or improved hip function in skeletally mature patients with select conditions. Under section 201(h) of the Federal Food, Drug, and Cosmetic Act (the Act), 21 U.S.C. § 321(h), these products are devices because they are intended for use in the diagnosis of disease or other conditions or in the cure, mitigation, treatment, or prevention of disease, or to affect the structure or any function of the body.
Quality System Regulation Violation(s)
This inspection revealed that these devices are adulterated within the meaning of section 501(h) of the Act, 21 U.S.C. § 351(h), in that the methods used in, or the facilities or controls used for, their manufacture, packing, storage, or installation are not in conformity with the current good manufacturing practice requirements of the Quality System regulation found at Title 21,
Code of Federal Regulations
(CFR), Part 820.
We received a response from Len Tokish, Vice President of Quality Assurance and Regulatory Affairs dated May 15, 2025, concerning our investigator’s observations noted on the Form FDA 483 (FDA 483), List of Inspectional Observations, that was issued to your firm. We address this response below, in relation to each of the noted violations. These violations include, but are not limited to, the following:
1. Failure to establish and maintain procedures to ensure that all purchased or otherwise received product and services conform to specified requirements, including quality requirements, that must be met by suppliers, contractors, and consultants and define the type and extent of control to be exercised over the product, services, suppliers, contractors, and consultants, based on the evaluation results, as required by 21 CFR 820.50.
Specifically, you failed to adequately implement the “Approved Supplier List” section of your “Supplier, Purchasing and Inspection Controls” procedure (SOP-013; Rev. 0-6; Effective: 4/25/16 - 2/3/25) which requires that you “
ensure compliance to ISO 13485
” for your Tier 1 suppliers as a “method of control” over approved suppliers. For example, you did not ensure compliance to the process validation requirements (clause 7.5.6) of ISO 13485 (Medical Devices – Quality Management Systems – Requirements for regulatory purposes) for the following three (3) Tier 1 suppliers in that you failed to adequately assess and/or document an assessment of the acceptability of their cleaning validations meant to demonstrate that in-process or final cleaning of your ELEOS Implant Devices and Instruments consistently meet your specifications for cleanliness:
a.
(b)(4)
– Tier
(b)(4)
Final Cleaner of ELEOS Implant Devices
i. You approved the
(b)(4)
cleaning validation test report TR-2771D-01 (Rev. 1-2; Approved: 1/24/19 and 9/10/21) from this supplier despite it failing to define the maximum allowable devices per gallon per run, as required by section 9.2 of the corresponding test protocol TP-2771D-01 (Rev. 2; Approved: 9/10/21) which states “***
The main cleaning parameters that can impact the efficacy of the cleaning process include ***Quantity of parts
(
(b)(4)
)***.”
Similarly, you approved
(b)(4)
cleaning validation test report TR-2771E-01 (Rev. 1; Approved: 3/18/19) from this supplier despite it failing to document the maximum allowable quantity of
(b)(4)
and
(b)(4)
per run, as required by sections 9.3, 9.4, and 9.5 of the corresponding test protocol TP-2771E-01 (Rev. 1; Approved: 8/28/18) which state “***
To validate the cleaning process, parts shall be cleaned using
(b)(4)
over
(b)(4)
runs***To create a
(b)(4)
batch of product***Clean what is expected to be a
“
(b)(4)
” load in
(b)(4)
***
A cleaning process should not alter the appearance of parts or cause damage. If applicable, appropriate fixtures to hold the components during cleaning should be included in the study and used in routine production
***.”
ii. You failed to adequately assess differences in product design and geometrical configurations of candidate devices for the adoption into device families of existing
(b)(4)
cleaning validations conducted by this supplier because you did not accurately answer guiding questions contained in your “
Assessment of Product Change or New Product Adoption for Cleaning Processes
” reports. For example:
 The AC-2772-01 (Rev. 01; Effective: 7/25/19) and AC-277D-01 (Rev. 2; Effective: 2/26/21) reports show that you failed to document rationale to support your answers of “no” to the question posed in section 2 – “
In relation to the existing product, does the candidate product have a similar or less complex design?
” – despite the candidate devices having 4 grooves, a drive, or a male thread compared to the worst-case and comparison devices, which have none of these features.
 The AC-2772-02 report (Rev. 1; Effective: 3/23/20) shows that you incorrectly answered “no” to the question posed in section 2 – “
In relation to the existing product, does the candidate product have fewer/smaller or equivalent cannulated portions or lumens?
” – when you compared the candidate device (segmental proximal femur, PF-2000L-02M), which has 7 cannulated holes, to the
(b)(4)
device (
(b)(4)
) and comparison devices (
(b)(4)
), which contain no holes.
b.
(b)(4)
– Tier 1
(b)(4)
Cleaner of ELEOS Implant Devices
Although requested during the inspection, your Vice President of Quality Affairs and Regulatory Affairs was unable to provide documentation that you assessed the adequacy of the cleaning validations conducted in 2009 by this supplier,
(b)(4)
. In reviewing the “Process Validation of***
(b)(4)
Clean Line” Operational Qualification (OQ) (E118-2116; Rev. 1; Approved: 1/9/09) and Performance Qualification (PQ) (E118-2116; Rev. 1; Approved: 2/3/09), the following deficiencies were observed:
i. The rationale in the PQ report to accept deviations from the nominal operating range of
(b)(4)
°F (
(b)(4)
, and
(b)(4)
°F) because OQ data showed that the process monitoring, total organic carbon (TOC), and gravimetric produced acceptable results at worst-case conditions for temperatures as low as
(b)(4)
°F and control charts indicated a lower control limit of
(b)(4)
°F (Deviation 3) does not take into account the vast differences in sample sizes (
(b)(4)
vs.
(b)(4)
) and acceptance criterion (Ppk
(b)(4)
vs. Ppk
(b)(4)
) between PQ and OQ for the same tests (TOC and gravimetric analysis) such that passing results for parameters established during OQ are not transferrable to PQ.
ii. This supplier failed to document rationale in the OQ and PQ reports for why it was acceptable to convert all negative values measured for the corrected “
mass recovered from gravimetric
(b)(4)
and corrected “
mass recovered from
(b)(4)
to 0.00 mg in the “
Gravimetric Extraction Summary
” table during gravimetric testing, thereby passing the acceptance criteria of
(b)(4)
mg/cm
2
(
(b)(4)
). For example, during OQ, an
(b)(4)
value as high as -1.59 mg for “Hip – 4” was converted to 0.00 mg without an explanation that accounts for the possibility of testing errors, inadequate test methodology (e.g., lack of sensitivity of testing methods), and uncalibrated state of measuring equipment.
c.
(b)(4)
–
(b)(4)
Cleaner of ELEOS Implant Devices &
(b)(4)
Cleaner of ELEOS Instruments
You approved the adoption of new products into this supplier’s existing
(b)(4)
cleaning validations titled “
(b)(4)
Cleaning Equipment & Performance Qualification Report” (FR_920-001; Rev. B; Effective: 3/31/15) and “Zenith Final Ultrasonic Cleaning Equipment & Performance Qualification Report” (FR_920-001; Rev. B; Effective: 3/31/15) per your Cleaning, Assembly, Packaging and Sterility (CAPS) Checklists for Project # 16-001 (Approved 10/2/24) and Project # 16-003 (Approved 4/19/24) referencing memo “
(b)(4)
Cleaning” (2/14/19) and results of a 3rd party audit conducted 2/23/18 despite the following deficiencies:
i. The OQ and PQ protocols failed to require documentation of the load configurations for all work orders in that the Vice President of Quality Affairs and Regulatory Affairs was not able to determine if devices were put in a
(b)(4)
or broken up into
(b)(4)
.
ii. The PQ protocol failed to include documentation of valid statistical rationale for cytotoxicity, endotoxin, and/or particulate testing. For example, the quantity tested per work order (66672, 66921, 66922) for cytotoxicity and endotoxin was
(b)(4)
and
(b)(4)
respectively and the quantity tested per work order (66675, 66919, 66920) for cytotoxicity, endotoxin, and particulate was
(b)(4)
and
(b)(4)
, respectively.
We reviewed your firm’s response and concluded that it is not adequate. The immediate correction is to impose heightened controls at each supplier commensurate with risk until new worst-case cleaning validations can be completed that addresses each of the observed deficiencies for
(b)(4)
by 1/15/26,
(b)(4)
(target date not provided), and
(b)(4)
by 3/1/26 at the latest.
For
(b)(4)
, an assessment of worst-case part justification by family was completed to establish new limits placed on
(b)(4)
, and
(b)(4)
. You plan to add this new loading criteria to the final DHR review by 7/15/25. In addition, you plan to require an update to
(b)(4)
internal procedure to include predicate cleaning validation review by 7/15/25. Based on the results of the new cleaning validation, you plan to revise top level procedures by
(b)(4)
.
For
(b)(4)
, an assessment of worst-case part justification was conducted and monitoring was put in place to control product release by assessing endotoxicity and cytotoxicity on a
(b)(4)
basis. In addition, you plan to require an update to this supplier’s internal procedures to improve notification of triggers to their customers by 7/1/25.
For
(b)(4)
, you plan to conduct an assessment for worst-case part challenge per part family by
(b)(4)
. For all instruments, interim clean line controls were implemented to require shipment of instruments to your firm and analyses of those instruments, which includes worst-case part and part family assessments prior to adoption into your clean-line part family. All parts successfully assessed will then be cleaned using your validated clean line prior to release for commercial distribution. All implants will continue to be shipped to
(b)(4)
for
(b)(4)
cleaning and will fall under controls established for therein.
Corrective actions include updating your supplier control and design control procedures to establish minimum requirements for cleaning validations of implants and instruments, including defining key product attributes to consider when forming product families and what considerations trigger a new worst-case within a product family or new product cleaning family; creation of a procedure for part families and worst-case parts per family which defines and evaluates implant and instrument cleaning families to facilitate consistent assessment of device cleaning families across products; determination and justification of minimum sample size and attributes (
(b)(4)
) for validations; development of a cleaning validation checklist and modification of a supplier audit checklist that captures the aforementioned worst-case part determination, sample sizes, and minimum attributes that will be used during supplier assessment as part of design transfer and new supplier onboarding, manufacturing transfer, and supplier audit; and periodic review of validations on a scheduled interval against new standards and requirements by 6/15/25.
However, no target date was provided for the new cleaning validation planned for
(b)(4)
. Therefore, please provide a response regarding how you plan to address this deficiency. In addition, please continue to provide updates on the progress of your corrections and/or corrective actions, including any supporting evidence.
2. Failure to establish and maintain procedures for implementing corrective and preventive action, as required by 21 CFR 820.100(a).
Specifically, you failed to implement your Post Market Surveillance procedure (QP-18-004; Rev. 3; Effective: 6/30/22) which requires opening a CAPA when the
(b)(4)
analysis of infection complaints “***
is more than
(b)(4)
above the literature rate or
(b)(4)
are above the literature rate
***” for a given procedure type. For example, you did not initiate CAPAs when the
(b)(4)
analysis for infection complaints exceeded the rates of
(b)(4)
% for the distal femur (
(b)(4)
);
(b)(4)
% for proximal femur (
(b)(4)
and
(b)(4)
); and
(b)(4)
% for total femur (
(b)(4)
and
(b)(4)
) established in the journal article by Henderson et. al “
Failure Mode Classification for Tumor Endoprostheses: Retrospective Review of Five Institutions and a Literature Review
” (Journal Bone and Joint Surgery 2011) by
(b)(4)
.
The adequacy of the response dated 5/15/25 cannot be determined at this time. Under CAPA 24-011 which was initiated on 9/11/24 to create a more robust methodology for trending and analyzing infection related complaints, you conducted a revised retrospective assessment of
(b)(4)
infection rates from
(b)(4)
to
(b)(4)
(TM-25-0002; Rev. B; Approved 5/14/25) based on additional literature data to support updated baseline infection rates by procedure type. As a part of the corrective action, you plan to create new work instructions with requirements to perform
(b)(4)
trend reporting for infections and
(b)(4)
or
(b)(4)
trend reports for all other postmarket surveillance key performance indicators (KPIs); revise management review presentation slides and quality planning, postmarket surveillance, complaint handling, and CAPA procedures; and provide training on the new procedures. Please continue to provide updates on the progress of your corrections and/or corrective actions, including any supporting evidence.
3. Failure to adequately establish and maintain procedures for validating the device design with regards to risk analysis, as required by 21 CFR 820.30(g).
Specifically, you failed to implement section 5.9 of your “Risk Management Process” procedure (SOP-008; Rev. 4-5; Effective: 3/22/23 - 1/17/25) which requires postmarket re-evaluation of risk management for a medical device as well as monitoring of postmarket information “***
for assurance that no unacceptable or previously unrecognized failure modes occur. In the event of such an occurrence the potential that the residual risk or its acceptability has changed and the impact on the previously implemented risk control measures shall be evaluated
***.” For example, you failed to utilize the real rate of occurrence for loosening in complaints PCR 11272023-1 (
(b)(4)
), PCR 05132024-1 (
(b)(4)
), and PCR 10172024-1 (
(b)(4)
) calculated at 3.27%, 0.149%, and 3.1%, respectively, to evaluate the need to update the occurrence rating in the corresponding ELEOS Stem Implant Risk Table (Project # 16-001/16-003; Rev. E; Approved: 4/1/19), which remains unchanged at
(b)(4)
% through
(b)(4)
% since April 1, 2019.
An update to the postmarket rate of occurrence changes the failure mode from an acceptable risk to a conditionally acceptable risk, thereby requiring an evaluation for the need for additional risk controls and assessment for the acceptability of the residual risk as required under sections 5.6 and 5.7 of SOP-008.
The adequacy of the response dated 5/15/25 cannot be determined at this time. The immediate correction is to evaluate literature, sources, historical data, and/or engineering estimates against postmarket data and update the occurrence rates for the hazardous situations associated with the ELEOS Limb Salvage system by
(b)(4)
followed by a revision of the corresponding risk tables by
(b)(4)
. As a part of the corrective action, you plan to revise SOP-008 to ensure that the methods used to create and maintain risk assessment tables are well-defined and create work instructions for conducting risk assessments utilizing postmarket information by
(b)(4)
. Please continue to provide updates on the progress of your corrections and/or corrective actions, including any supporting evidence.
4. Failure to establish and maintain procedures for identifying valid statistical techniques required for establishing, controlling, and verifying the acceptability of process capability and product characteristics, as required by 21 CFR 820.250(a).
Specifically, you failed to implement section 1.1 of your “Sample Size and Statistical Techniques” procedure (SOP-014; Rev. 2-4; Effective: 8/16/18 - 3/22/23) which “***
identifies valid statistical techniques that are used to establish, control and verify the acceptability of process capability and product characteristics***” pertaining to “***inspections and other analyses of objective data
***” of ELEOS Implant Devices received from
(b)(4)
. during incoming inspections. For example, your Vice President of Quality Affairs and Regulatory Affairs acknowledged that the sampling plans of the
(b)(4)
sampled incoming device history records (DHRs) from this supplier were not traceable to a documented valid statistical rationale.
a. You reviewed and approved incoming DHRs for Lot #
(b)(4)
and Lot #
(b)(4)
on 11/2/20 and 11/29/21 where a sampling plan of
(b)(4)
was used to inspect critical features during in-process inspections for which there is no documented rationale for use of this sampling plan. For example, out of
(b)(4)
ELEOS Tibial Baseplate Component, Size 4 (Part # TB-2204E-01M) Implant Devices, the line profile (curve) for
(b)(4)
each were inspected against a specification of
(b)(4)
at
(b)(4)
for Lot #
(b)(4)
. Similarly, out of
(b)(4)
ELEOS Collar, 28 Diameter, Round, Porous, HA Treated (Part # HB-2800R-03M) Implant Devices, the diameter for
(b)(4)
each was inspected against a specification of
(b)(4)
at
(b)(4)
for Lot #
(b)(4)
.
b. You reviewed and approved incoming DHRs (Lot #:
(b)(4)
) where sampling plans utilized an AQL (acceptable quality limit) of
(b)(4)
or
(b)(4)
to inspect features during in-process and final inspections for which there are no documented rationales for use of these sampling plans. For example, out of
(b)(4)
ELEOS Segmental Proximal Femur, Plasma Spray, Left 98 MM (Part # PF-2000L-02M) Implant Devices, the dimensional specification of
(b)(4)
was inspected at an AQL level of
(b)(4)
for Lot #
(b)(4)
during final inspection on 1/23/24.
We reviewed your firm’s response and concluded that it is not adequate. The immediate corrections are to use a checklist to reassess and document rationales for acceptability of the existing AQLs selected for all contract manufactured ELEOS part families from 1/1/21 to 4/1/25 and share the rationales with the contract manufacturers by 11/21/25 and update SCAR 25-01 to require the contract manufacturer to include documented evidence for all inspected dimensions and associated AQL quantities by 5/14/25. As a part of the corrective actions, you plan to update SOP-014 and WI-013-31 (Incoming Inspection Process) to require review of incoming inspection results, consolidation of sampling procedures, set up traceable valid statistical rationales, and confirm AQLs by 7/6/25; update SOP-007 (Design Control) and various design transfer, manufacturing transfer, supplier, and incoming inspection checklists to include instructions for the acceptance of a supplier’s sampling procedure with confirmation of conformance to those procedures during incoming inspection of supplier DHRs by
(b)(4)
; and develop
(b)(4)
inspection requirement checklists for all suppliers with a sampling procedure traceable to a valid statistical rationale based on
(b)(4)
by 7/18/25. However, these corrections and/or corrective actions only address the need to have a statistically valid rationale for the use of sampling plans which follow AQL and not sampling plans which utilize inspections of select critical features for the
(b)(4)
devices. Therefore, please provide a response on how you plan to address the above deficiency. In addition, please continue to provide updates on the progress of your corrections and/or corrective actions, including any supporting evidence.
Corrections and Removals Violation(s)
Our inspection also revealed that your firm’s ELEOS Limb Salvage System devices are misbranded under section 502(t)(2) of the Act, 21 U.S.C. § 352(t)(2), in that your firm failed or refused to furnish material or information respecting the device that is required by or under section 519 of the Act, 21 U.S.C. § 360i, and 21 CFR Part 806 – Medical Devices; Reports of Corrections and Removals. Significant violations include, but are not limited to, the following:
5. Failure to submit a medical device Report of Correction or Removal for an action initiated to reduce a risk to health posed by the device or remedy a violation which may present a risk to health, as required by 21 CFR Part 806.10. For example:
a. Your firm conducted a removal of numerous part numbers and lot numbers of your ELEOS Limb Salvage System due to sterile packaging separation and damaged trays, which can result in extended surgery time or potential patient infection. Your firm sent a Customer Notification for this issue on 6/28/2023. This action meets the definition of a medical device correction or removal initiated to reduce a risk to health or remedy a violation which may present a risk to health, for which you are required to submit a Report of Correction or Removal to FDA. You did not submit a Medical Device Report of Correction or Removal to FDA for this action until after the investigation and citation.
b. On or about 10/15/2024, your firm conducted a removal of your ELEOS Limb Salvage System, Male-Female Midsection 40MM, due to taper post misalignment, which can result in extended surgery time or improperly assembled devices leading to future disassociation. Your firm sent a Customer Notification for this issue dated 9/20/2024. This action meets the definition of a medical device correction or removal initiated to remedy a violation which may present a risk to health, for which you are required to submit a Report of Correction or Removal to FDA. You did not submit a Medical Device Report of Correction or Removal to FDA for this action until after the investigation and citation.
c. On or about 1/22/2024, your firm conducted a removal of your ELEOS Limb Salvage System, Collar Stem, Cemented, Fluted 13MM X 120MM and Collar Stem, Cemented, Fluted 15MM X 120MM due to mislabeling of the devices, which can result in implantation or attempted implantation of an incorrect stem size, potentially extending surgery time or causing the patient to need revision surgery. Your firm sent a Customer Notification for this issue on 12/22/2023. This action meets the definition of a medical device correction or removal initiated to remedy a violation which may present a risk to health, for which you are required to submit a Report of Correction or Removal to FDA. You did not submit a Medical Device Report of Correction or Removal to FDA for this action until after the investigation and citation.
The adequacy of your firm’s response, dated 5/14/2025, regarding Observation 5 cannot be determined because we do not have assurance that your firm will make appropriate decisions following 21 CFR 806 in the future, based on your firm’s root cause stating that your firm’s SOP is ambiguous and subjective. Your firm adequately reported by retroactively submitting Reports of Correction or Removal to FDA addressing each of the three issues on 4/25/2025.
Your firm should take prompt action to address any violations identified in this letter. Failure to 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.
Other federal agencies may take your compliance with the FD&C Act and its implementing regulations into account when considering the award of federal contracts. Additionally, should FDA determine that you have Quality System regulation violations that are reasonably related to premarket approval applications for Class III devices, such devices will not be approved until the violations have been addressed. Should FDA determine that your devices or facilities do not meet the requirements of the Act, requests for Certificates to Foreign Governments (CFG) may not be granted.
Please notify this 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 actions (which must address systemic problems) that your 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 products are not in violation of the FD&C Act, include your reasoning and any supporting information for our consideration as part of your response.
Your firm’s response should be sent via email to Gina Brackett, Establishment Assessment Team 1 (EAT-1) Assistant Director at CDRHEnforcement@fda.hhs.gov. Please include in the subject line, “CMS Case # 712573” when replying. If you have any questions about the contents of this letter, please contact: Sargum C. Morgan, Compliance Officer at sargum.morgan@fda.hhs.gov.
Finally, you should know that this letter is not intended to be an all-inclusive list of the violations at your firm’s facility. It is your firm’s responsibility to ensure compliance with applicable laws and regulations administered by FDA. The specific violations noted in this letter and in the Inspectional Observations, FDA 483, issued at the close of the inspection may be symptomatic of serious problems in your firm’s manufacturing and quality management systems. Your firm should investigate and determine the causes of any violations and take prompt actions to address any violations and bring the products into compliance.
Sincerely,
/S/
Matthew G. Hillebrenner
Deputy Director
Office of Product Evaluation and Quality
Center for Devices and Radiological Health
CC: Len Tokish
VP of Quality Assurance & Regulatory Affairs
ltokish@onkossurgical.com
Content current as of:
07/29/2025
Regulated Product(s)
Medical Devices