Para-Fix™ C&S Medium provides a method for collecting and preserving fecal specimens for the culture of intestinal enteric bacteria. Because the medium is capable of maintaining the bacteria for 96 hours, immediate transportation and processing of the specimen is not necessary.

Device Description

Para-Fix C&S Medium is a non-nutritive, buffered, isotonic solution with a pH indicator added. The medium also contains agar and sodium thioglycolate to maintain a low oxygen tension for the preservation of anaerobic species. The phenol red indicator will turn yellow when the solution is acidic and the conditions are not optimal for recovery of the intended organisms. Each 30 mL vial contains 15 ml of solution and a built in sample collection spoon. The kit is available with or without a multilingual instruction sheet and re-sealable bag.

AI/ML Overview

Here's a breakdown of the acceptance criteria and the studies performed for the MCC Para-Fix C&S Medium, based on the provided document:

Acceptance Criteria and Reported Device Performance

Acceptance Criteria	Reported Device Performance
Bateriostasis / Preservation Ability: Maintain representative bacterial species, including potential pathogens found in fecal samples, with the number of viable organisms remaining within ±2 log10 of the original inoculum for 96 hours at 2-8°C and 20-25°C. This criterion is specified by Clinical and Laboratory Standards Institute (CLSI), M40-A2.	Met:- Without Fecal Matrix (Swab Elution Method): All 10 tested enteric organisms (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica, Bacillus subtilis, Vibrio parahaemolyticus, Clostridium difficile, Campylobacter jejuni, Enterococcus faecalis, Shigella dysenteriae) showed log reduction/increase values well within the ±2 log10 criterion after 96 hours at both 2-8°C and 20-25°C. The maximum observed log change was 1.34 (Pseudomonas aeruginosa at 20-25°C), and the minimum was -0.02 (Salmonella enterica at 2-8°C).- With Fecal Matrix (Roll-Plate Method): Salmonella enterica, Vibrio parahaemolyticus, and Escherichia coli generally showed log reduction/increase values within the ±2 log10 criterion after 120 hours at 2-8°C. (Note: Many results at 72, 96, and 120 hours for 20-25°C were "Too numerous to count," indicating significant growth, which still suggests preservation and recovery).- With Fecal Matrix (Swab Elution Method): Salmonella enterica, Vibrio parahaemolyticus, and Escherichia coli generally showed log reduction/increase values within the ±2 log10 criterion after 120 hours at both 2-8°C and 20-25°C. Max log increase was +0.88, max log reduction was -0.23.
Shelf-Life Stability: The product must maintain bacteria inocula (within ±2 log10 of original counts) on vials exceeding the 18-month expiration dating (worst-case condition).	Met: Bacterial counts for newly manufactured vials and vials exceeding expiration dating were within ±2 log10 of the original inoculum at the time of inoculation and 96 hours later.
Bioburden: No viable organisms should be present. Absence of Gram-positive or Gram-negative organisms by Gram staining.	Met: No viable organisms found in any lots tested at time of manufacture. No Gram-positive or Gram-negative organisms detected after end of expiration dating by Gram staining.
pH Value: pH of the product should be within an acceptable range.	Met: pH value at the time of testing was between 7.08 to 7.83. (Acceptable range is implied by compliance with the predicate device and functional performance).
Vial Pressure Test: 95 kPa.	Met: Vial pressure test reported as 95 kPa.
Container: 30 mL Vial.	Met: 30 mL Vial.
Closure: Screw cap & spork.	Met: Screw cap & spork.
Formulation: Cary Blair - modified.	Met: Cary Blair - modified.
Fill Volume: 15 mL.	Met: 15 mL.
Storage Temperature: 20-30°C.	Met: 20-30°C. (The study tested 2-8°C and 20-25°C which falls within this range).
Buffer System: Phosphate.	Met: Phosphate.
Oxygen Tension: Thioglycolate.	Met: Thioglycolate.
pH Indicator: Phenol red.	Met: Phenol red.

Study Information

Sample Size used for the test set and the data provenance:
- Test Set (without fecal matrix): The specific number of replicates per organism and temperature condition is not explicitly stated, but the tables provide "Average CFU's Recovered," implying multiple measurements. There were 10 different enteric organisms tested at two temperature conditions (2-8°C and 20-25°C).
- Test Set (with fecal matrix): For the "Representative Enteric organism recovery results for Para-Fix™ C&S Medium using Roll-Plate Method" and "Swab Elution Method", three organisms were tested (Salmonella enterica, Vibrio parahaemolyticus, Escherichia coli) at two temperature conditions, with measurements at 0, 72, 96, and 120 hours. Again, "Average CFU's Recovered" implies multiple runs.
- Data Provenance: The study used "clinically negative human fecal matrix." No specific country of origin is mentioned, but it is a laboratory study, likely prospective, evaluating the performance of the device under controlled conditions.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable for this type of performance study. The ground truth (initial bacterial counts and subsequent counts after storage) was established through quantitative microbiological methods (plate counts, CFU determination) performed in a laboratory, rather than expert interpretation of a diagnostic outcome.
Adjudication method for the test set:
- Not applicable. This is a quantitative laboratory performance study, not a clinical study involving human interpretation or consensus.
If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
- Not applicable. This device is a transport medium for laboratory samples, not an AI-assisted diagnostic tool requiring human reader studies.
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Yes, this was a standalone performance study of the physical device (transport medium). There is no "algorithm" or "human-in-the-loop" component. The device's ability to preserve organisms was tested directly.
The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Quantitative Microbiological Analysis: The ground truth was based on quantitative culture results (Colony Forming Units - CFUs) obtained through standard laboratory techniques (plate counts, swab elution, roll-plate methods) for specific bacterial organisms under controlled conditions. This is a direct measurement of the device's functional performance.
The sample size for the training set:
- Not applicable. This is not a machine learning or AI-based device, so there is no training set in that context. The "training" of the medium itself is its chemical formulation and manufacturing process.
How the ground truth for the training set was established:
- Not applicable, as there is no training set in the context of an algorithmic or AI device. The "ground truth" for the device's design and formulation would have been established through traditional microbiology and chemistry research and development, aiming to meet established standards like CLSI M40-A2 for transport media.

Summary

{0}------------------------------------------------

Image /page/0/Picture/1 description: The image shows the logo for the Department of Health & Human Services - USA. The logo is a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is a stylized image of three human profiles facing to the right, stacked on top of each other.

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

May 28, 2015

MEDICAL CHEMICAL CORPORATION KRIS KONTIS VP REGULATORY AFFAIRS 19430 VAN NESS AVE TORRANCE CA 90501-1104

Re: K150887

Trade/Device Name: Para-fix C&S Medium Regulation Number: 21 CFR 866.2390 Regulation Name: Transport culture medium Regulatory Class: I Product Code: JSM, LIO Dated: March 30, 2015 Received: April 3, 2015

Dear Dr. Kontis:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food. Drug. and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21. Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

{1}------------------------------------------------

If you desire specific advice for your device on our labeling regulations (21 CFR Parts 801 and 809), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638 2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours,

Sally A. Hojvat -S

Sally Hojvat, M.Sc., Ph.D. Director Division of Microbiology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

{2}------------------------------------------------

Indications for Use

510(k) Number (if known) K150887

Device Name

MCC Para-Fix C&S Medium

Indications for Use (Describe)

Type of Use (Select one or both, as applicable)

Prescription Use (Part 21 CFR 801 Subpart D)
Over-The-Counter Use (21 CFR 801 Subpart C)

CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.

The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:

Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff PRAStaff@fda.hhs.gov

"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."

{3}------------------------------------------------

510(k) Summary Medical Chemical Corporation Para-Fix C&S Medium

Sponsor Medical Chemical Corporation 19430 Van Ness Ave. Torrance, California 90501-1104 Contact: Kris Kontis Telephone number (800) 424-9394 Date: March 24, 2015

Device Name

Trade Names: MCC Para-Fix™ C&S Medium Common Name: Transport Vials Classification Name: Culture Media, Non-Propagating Transport (JSM)

Requlatory Information

Regulatory Section 21 CFR 866.2390 Classification Class I Product Code: JSM, LIO Panel Microbiology

Predicate Device

Meridian Para-Pak C&S 510(k) Number: K792712

Device Description

Intended Use

Para-Fix C&S Medium provides a method for collecting and preserving fecal specimens for the culture of intestinal enteric bacteria. Because the medium is capable of maintaining the bacteria for 96 hours, immediate transportation and processing of the specimen is not necessary.

Indication(s) for Use

Substantial Equivalence Statement

Medical Chemical Corporation Para-Fix C&S medium is similar in design, manufacturing and intended usage to the predicate device. Both the Para-Fix C&S and the predicate device are single use devices intended for collection and transport of clinical specimens containing enteric organisms.

{4}------------------------------------------------

Device Comparison Table

Technical Attribute	Para-Fix C&S (K150887)	Meridian Para-Pak C&S(K792712)
Container	30 mL Vial	30 mL Vial
Closure	Screw cap & spork	Screw cap & spork
Vial pressure test	95 kPa	unknown
Formulation	Cary Blair - modified	Cary Blair - modified
Fill volume	15 mL	15 mL
Storage temperature	20-30°C	20-30°C
Buffer system	Phosphate	Phosphate
Oxygen tension	Thioglycolate	Thioglycolate
pH indicator	Phenol red	Phenol red

Performance Testing

MCC Para-Fix C&S Medium is intended to be used as a non-propagating preservative for fecal specimens being able to prevent the significant loss of organisms that may be pathogenic and to prevent the overgrowth by normal intestinal flora. The bacteriostasis study demonstrates that Para-Fix C&S Medium preserves representative bacterial species for 96 hours at 2-8°C and 20-25°C. These species include potential pathogens that may be found in fecal samples: Campylobacter jejuni, Clostridium difficile. Enterococcus faecalis. Bacillus subtilis. Staphylococcus aureus. Escherichia coli. Pseudomonas aeruginosa, Salmonella enterica, Shigella dysenteriae, and Vibrio parahaemolyticus. The data showed that the number of viable organisms remained within ±2 log10 of the original inoculum. This is consistent with the intended use of the predicate device and demonstrates substantial equivalence.

Performance was tested in two ways. Para-Fix C&S Medium was tested for its ability to maintain enteric organisms using the plate count technique.

First C&S wials were seeded with suspensions of enteric orqanisms in the absence of fecal matrix. Vials were held at 2-8°C and 20-25°C and sampled at 0 and 96 hours by Swab Elution plate counts. Orqanisms were cultured on appropriate media to assure accurate recovery of seeded organisms. The performance criterion as specified by Cinical and Laboratory Standards Institute (CLSI), M40-A2 was met for the 10 enteric organisms previously listed. The results are shown in the following table:

{5}------------------------------------------------

All Enteric Organism recovery results for Para-Fix C&S Medium using Swab Elution Method.

Organism*	HoldTemperature	Average CFU'sRecovered:Time 0 hrs	Average CFU'sRecovered:Time 96 hrs	T=96 hrs Logreduction/Log increase
Escherichia coli	2-8°C	1.6 X 107	5.1 X 107	0.51
Escherichia coli	20-25°C	2.1 X 107	2.5 X 106	1.09
Staphylococcus aureus	2-8°C	1.6 X 107	1.4 X 107	-0.04
Staphylococcus aureus	20-25°C	1.5 X 107	2.4 X 107	0.20
Pseudomonasaeruginosa	2-8°C	8.1 X 106	6.2 X 106	-0.12
Pseudomonasaeruginosa	20-25°C	9.2 X 106	2.0 X 106	1.34
Salmonella enterica	2-8°C	6.1 X 107	5.8 X 107	-0.02
Salmonella enterica	20-25°C	5.6 X 107	2.1 X 106	0.57
Bacillus subtilis	2-8°C	3.6 X 106	4.0 X 106	0.04
Bacillus subtilis	20-25°C	4.6 X 106	1.6 X 107	0.54
Vibrio parahaemolyticus	2-8°C	9.8 X 106	8.9 X 106	-0.04
Vibrio parahaemolyticus	20-25°C	9.8 X 106	8.8 X 106	-0.05
Clostridium difficile	2-8°C	1.2 X 107	1.0 X 107	-0.06
Clostridium difficile	20-25°C	1.1 X 107	9.5 X 106	-0.06
Campylobacter jejuni	2-8°C	5.8 X 107	5.0 X 107	-0.07
Campylobacter jejuni	20-25°C	4.0 X 107	3.5 X 107	-0.06
Enterococcus faecalis	2-8°C	2.3 X 107	2.1 X 107	-0.04
Enterococcus faecalis	20-25°C	2.2 X 107	1.8 X 107	-0.10
Shigella dysenteriae	2-8°C	2.2 X 107	1.4 X 107	-0.19
Shigella dysenteriae	20-25°C	2.4 X 107	5.1 X 106	-0.68

*0.5 McFarland microorganism suspension diluted with C&S Medium at 1:15

Second, Para-Fix C&S Medium was tested for its ability to maintain pathogenic enteric organisms spiked into clinically negative human fecal matrix. Clinically negative human fecal matrix was added to C&S vials that were then seeded with suspensions of enteric organisms. Vials were held at 2-8℃ and 20-25°C and sampled at 0, 72, 96 and 120 hours by serial dilution plate counts, and by the Roll-Plate method using sterile swabs (Fisher 23-400-122). Organisms were cultured on selective media to assure accurate recovery of seeded organisms. The performance criterion as specified by CLSI M40-A2 was met for Swab Elution or the Roll-Plate method. The results are shown in the following tables:

{6}------------------------------------------------

Representative Enteric organism recovery results for Para-Fix™ C&S Medium using Roll-Plate Method.

Organism	HoldTemperature	AverageCFU'sRecovered:Time 0 hrs	AverageCFU'sRecovered:Time 72 hrs	AverageCFU'sRecovered:Time 96 hrs	AverageCFU'sRecovered:Time 120hrs	T=120 hrslogreduction(-)or logincrease (+)
Salmonellaenterica	2-8°C	190	192	162	97	-0.29
enterica	20-25°*C	64	**	**	**	N/A
Vibrioparahaemolyticus	2-8°C	220	160	63	68	-0.51
parahaemolyticus	20-25°C	130	**	**	**	N/A
Escherichiacoli	2-8°C	110	48	83	71	-0.19
coli	20-25°C	70	**	**	**	N/A
0.5 McFarland microorganism suspension diluted with fecal matrix and C&S Medium to 2.0 X 104 unless
noted
* diluted 2.0 X 105
** Too numerous to count

Representative Enteric organism recovery results for Para-Fix™ C&S Medium using Swab Elution Method.

Organism	HoldTemperature	AverageCFU'sRecovered:Time 0 hrs	AverageCFU'sRecovered:Time 72 hrs	AverageCFU'sRecovered:Time 96 hrs	AverageCFU'sRecovered:Time 120hrs	T=120 hrslogreduction(-)or logincrease (+)
Salmonellaenterica	2-8°C	2.7 X 102	2.9 X 102	3.0 X 102	2.0 X 102	-0.13
	20-25°C	3.2 X 102	**	**	**	N/A
Vibrioparahaemolyticus	2-8°C	2.2 X 102	1.6 X 102	6.3 X 102	6.8 X 102	+0.49
	20-25°C	2.5 X 102	**	**	**	N/A
Escherichiacoli	2-8°C	1.6 X 102	8.9 X 101	1.3 X 102	9.4 X 101	-0.23
	20-25°C	1.0 X 102	6.8 X 102	5.4 X 102	7.6 X 102	+0.88
0.5 McFarland microorganism suspension diluted with fecal matrix and C&S Medium at 1:2000* Too numerous to count

Based on the comparison of technological attributes, functional testing of preservation ability, we conclude that MCC Para-Fix C&S Medium is substantially equivalent to the predicate device - Meridian Para-Pak C&S.

Bioburden

MCC Para-Fix C&S Medium was tested for the presence/absence of bioburden which could interfere with subsequent procedures. At the time of manufacture bioburden was tested by an aerobic plate count. No viable organisms were found in any lots of product tested. A further test was performed after the end of expiration dating consisting of Gram staining each lot of product. No Gram-positive or Gram-negative organisms were detected by this method. We concluded that the process used to manufacture these media are effective at eliminating viable organisms and preventing the appearance of any organisms, viable or non-viable, that can be Gram stained.

{7}------------------------------------------------

Stability Testing

Para-Fix C&S vials were tested for the products to maintain bacteria inocula on both newly manufactured vials and vials exceeding the expiration dating of 18 months, representing a worst-case condition with respect to shelf-life stability. Performance was assessed by determining the bacterial counts at the time of inoculation and 96 hours later. In all cases the bacterial counts were within ±2 logio, as specified in the performance criteria for this study. We conclude that C&S Medium passes the performance criteria at the time of manufacture and after shelf-life expiration.

pH Stability

The pH value of the product at the time of testing was between 7.08 to 7.83 for Para-Fix C&S Medium.

Sterilization

MCC Para-Fix C&S vials are not sold as sterile. Although there is no sterlity claim, the manufacturing process includes treatment of finished vials in a steam chamber for 30 minutes to eliminate bioburden.

Regulation Number and Section

§ 866.2390 Transport culture medium.

(a)
Identification. A transport culture medium is a device that consists of a semisolid, usually non-nutrient, medium that maintains the viability of suspected pathogens contained in patient specimens while in transit from the specimen collection area to the laboratory. The device aids in the diagnosis of disease caused by pathogenic microorganisms and also provides epidemiological information on these diseases.(b)
Classification. Class I (general controls).