The BD MAX Check-Points CPO Assay performed on the BD MAX System is a qualitative, automated in vitro diagnostic real-time PCR test designed for the detection and differentiation of the carbapenemase genes blakes, blayble blaymoblance and black-48, that are associated with carbapenem non-susceptibility in Gram-negative bacteria. The assay does not distinguish between the blay™ and bland genes.

The BD MAX Check-Points CPO Assay is intended as an aid to infection control in the detection of carbapenem-non-susceptible bacteria that colonize patients in healthcare settings. The BD MAX Check-Points CPO Assay is not intended to guide or monitor treatment for carbapenem-non-susceptible bacterial infections. A negative BD MAX Check-Points CPO Assay result does not preclude the presence of other resistance mechanisms.

Testing is performed on rectal swabs from patients at risk for intestinal colonisation with carbapenem nonsusceptible bacteria. This test is intended for use in conjunction with clinical presentation, laboratory findings, and epidemiological information. Results of this test should not be used as the sole basis for patient management decisions. Concomitant cultures are necessary to recover organisms for epidemiological typing, antimicrobial susceptibility testing, and for further confirmatory bacterial identification.

Device Description

The BD MAX Check-Points CPO Assay detects the presence of carbapenemase genes in Gram-negative bacteria and includes an internal Sample Processing Control.

Rectal swab specimens are collected from patients using ESwab. After sampling they are transported to the laboratory in the Amies transport media of the ESwab. The ESwab is vortexed and a 50 µl aliquot is transferred to the Sample Buffer Tube using a pipette with disposable filter tip. The Sample Buffer Tube is closed with a septum cap and vortexed. Once the worklist is generated and the clinical specimen is loaded on the BD MAX system, along with a BD MAX Check-Points CPO Reagent Strip and BD MAX PCR Cartridge, the run is started and no further operator intervention is required. The BD MAX System automates sample preparation, including target organism lysis, DNA extraction and concentration, reagent rehydration, target nucleic acid sequence amplification and detection using real-time PCR. The interpretation of the signal is performed automatically by the BD MAX System. The assay also includes a Sample Processing Control that is provided in the Extraction Tube and subjected to extraction, concentration and amplification steps. The Sample Processing Control monitors for the presence of potential inhibitory substances as well as system or reagent failures.

Following enzymatic cell lysis at an elevated temperature, the released nucleic acids are captured on magnetic affinity beads. The beads, with the bound nucleic acids, are washed and the nucleic acids are eluted. Eluted DNA is neutralized and transferred to the Master Mix Tube to rehydrate the PCR reagents. After rehydration, the BD MAX System dispenses a fixed volume of PCR-ready solution into the BD MAX PCR Cartridge. Microvalves in the BD MAX PCR Cartridge are sealed by the system prior to initiating PCR to contain the amplification mixture thus preventing evaporation and contamination. The amplified DNA targets are detected using hydrolysis (TaqMan®) probes, labeled at one end with a fluorescent reporter dve (fluorophore) and at the other end with a quencher moiety. Probes labeled with different fluorophores are used to detect amplicons for the carbapenemase genes KPC, VIM, OXA-48, NDM, IMP and the Sample Processing Control in five different optical channels of the BD MAX System.

The VIM and IMP genes are combined in one optical channel of the BD MAX system, all other genes have a separate optical channel. When the probes are in their native state, the fluorescence of the fluorophore is quenched due to its proximity to the quencher. However, in the presence of target DNA, the probes hybridize to their complementary sequences and are hydrolyzed by the 5'-3' exonuclease activity of the DNA polymerase as it synthesizes the nascent strand along the DNA template. As a result, the fluorophores are separated from the quencher molecules and fluorescence is emitted. The BD MAX System monitors these signals at each cvcle and interprets the data at the end of the program to report the final results.

AI/ML Overview

The provided document describes the performance characteristics of the BD MAX Check-Points CPO Assay. This device is a qualitative, automated in vitro diagnostic real-time PCR test for the detection and differentiation of specific carbapenemase genes (blaKPC, blaVIM/blaIMP, blaOXA-48, and blaNDM).

Here's an analysis of the acceptance criteria and the study that proves the device meets them:

1. Table of Acceptance Criteria and Reported Device Performance:

The document doesn't explicitly state "acceptance criteria" in a separate section with specific numerical thresholds for sensitivity and specificity. However, based on the presentation of "Performance Results" with 95% Confidence Intervals (CI), it's implied that the device is deemed acceptable if these performance metrics are sufficiently high and demonstrate clinical utility. The general expectation for diagnostic assays is high sensitivity and specificity.

Since direct acceptance criteria are not provided, I will present the reported performance, which implicitly met the FDA's requirements for substantial equivalence.

Performance Metric (Gene)	Acceptance Criteria (Implied)	Reported Device Performance (Prospective Study, MacConkey + chromID PCR/Sequencing)	Reported Device Performance (Contrived Study, PCR/Sequencing)
KPC Sensitivity/PPA	High (e.g., >85-90%)	88.2% (73.4-95.3% CI)	100% (88.6-100% CI)
KPC Specificity/NPA	High (e.g., >95-98%)	99.8% (99.4-99.9% CI)	100% (97.3-100% CI)
VIM/IMP Sensitivity/PPA	High (e.g., >85-90%)	75.0% (40.9-92.9% CI)	96.2% (87.0-98.9% CI)
VIM/IMP Specificity/NPA	High (e.g., >95-98%)	99.2% (98.7-99.6% CI)	100% (96.7-100% CI)
OXA-48 Sensitivity/PPA	High (e.g., >85-90%)	96.2% (81.1-99.3% CI)	100% (88.6-100% CI)
OXA-48 Specificity/NPA	High (e.g., >95-98%)	99.0% (98.3-99.4% CI)	100% (97.3-100% CI)
NDM Sensitivity/PPA	High (e.g., >85-90%)	100% (20.7-100% CI)	100% (88.6-100% CI)
NDM Specificity/NPA	High (e.g., >95-98%)	99.9% (99.6-100% CI)	100% (97.3-100% CI)
Non-Reportable Rate	Low (e.g., <5%)	0.1% (after repeat)	0%
Inclusivity (Target Variants Detected)	All or nearly all clinically relevant variants	All tested variants detected, including some not predicted by in silico analysis.	N/A
Analytical Specificity (Non-target detection)	No false positives from related or common organisms	All 26 tested organisms tested negative	N/A
Inter-lab Reproducibility	High (e.g., >90-95%)	Ranged from 97.5% - 100%	N/A
Inter-lot Reproducibility	High (e.g., >90-95%)	Ranged from 99.2% - 100%	N/A
Intra-lab Reproducibility	High (e.g., >90-95%)	Ranged from 97.9% - 100%	N/A
Carry-over Contamination	No positive calls from negative specimens after high-load positives	No positive calls in 166 negative specimens	N/A
Mixed Infection/Competitive Interference	No interference observed	No interference in 13 mixed specimens	N/A

2. Sample Sizes Used for the Test Set and Data Provenance:

Test Set Size:
- Prospective Specimens: 1486 initially collected, 1473 eligible for clinical evaluation after excluding unreportable ones.
- Contrived Specimens: 166.
- Analytical Inclusivity: 93 strains (containing 97 target genes).
- Analytical Specificity: 26 organisms tested.
- Interfering Substances: 29 substances tested.
- Reproducibility Studies (Inter-lab, Inter-lot, Intra-lab): Varied sample sizes per gene and concentration level, typically involving 60-120 replicates for positives and 72-100 for negatives per study type.
- Carry-over Contamination: 166 negative specimens.
- Mixed Infection/Competitive Interference: 13 specimens.
Data Provenance:
- Clinical (Prospective) Study: Samples collected from "five (5) geographically diverse clinical centers" as part of routine patient care. This indicates prospective collection from real-world clinical settings, likely within the country of the clinical centers (not explicitly stated, but generally implied to be within the jurisdiction of the submitting company or where clinical trials are feasible).
- Contrived Study: Specimens were prepared by spiking "well-characterized strains into unique negative rectal swab matrix." This is a laboratory-based study design.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:

The document does not mention the number or qualifications of experts involved in establishing the ground truth for the clinical specimens.
The ground truth for the clinical (prospective) study was established by a "reference method" consisting of:
- Bacterial culture for recovery of non-susceptible isolates from rectal swab specimens.
- Followed by detection of antibiotic resistance genes by PCR and sequencing.
- Bacterial culture protocol included both direct plating and overnight enrichment.
For contrived specimens, ground truth was also established by PCR and sequencing of the spiked strains.
For analytical inclusivity, strains were either from "public collections and well-characterized clinical isolates," implying previous expert characterization.

4. Adjudication Method for the Test Set:

The document does not describe an adjudication method involving multiple experts for the clinical test set results.
The comparison is between the BD MAX device results and the reference method (culture + PCR/sequencing), which serves as the established ground truth. Discrepancies would typically be reviewed by laboratory personnel, but a formal multi-expert adjudication process is not detailed.

5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, and the effect size of how much human readers improve with AI vs without AI assistance:

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done.
This device is an automated in vitro diagnostic real-time PCR test, not an AI-assisted imaging or diagnostic tool that involves human readers interpreting results with or without AI assistance. The results are interpreted automatically by the BD MAX System.

6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done:

Yes, this entire study is a standalone performance evaluation of the algorithm/device itself.
The "BD MAX System automates sample preparation, including target organism lysis, DNA extraction and concentration, reagent rehydration, target nucleic acid sequence amplification and detection using real-time PCR."
"The interpretation of the signal is performed automatically by the BD MAX System."
The performance tables directly compare the BD MAX Check-Points CPO (the device's output) to the gold standard reference method.

7. The type of ground truth used:

Expert Consensus + Laboratory Reference Method for Clinical Specimens: For prospective clinical specimens, the ground truth was established by a bacterial culture-based reference method including PCR and sequencing. While not explicitly "expert consensus" in the sense of multiple independent interpretations, the reliance on established laboratory techniques (culture, PCR, sequencing) for genetic characterization is a form of highly reliable, validated ground truth in molecular diagnostics.
Molecular Characterization for Contrived Specimens: For contrived specimens, the ground truth was based on the known molecular characteristics of the spiked strains, confirmed by PCR and sequencing.
Known Strain Characteristics for Analytical Studies: For inclusivity, specificity, LoD, and reproducibility studies, the ground truth was based on the known genetic profile and concentration of the bacterial strains used, confirmed by standard molecular methods (e.g., PCR and sequencing for gene presence).

8. The sample size for the training set:

The document does not provide information on a specific training set size because this is a molecular diagnostic assay, not a machine learning model that undergoes a distinct "training" phase with labeled data in the same way.
The development of such an assay involves extensive research and development to design primers and probes, optimize reaction conditions, and establish thresholds, but this is a different process than training an AI algorithm on a dataset. The analytical studies (LoD, inclusivity, specificity) demonstrate the robustness and limits of the assay design.

9. How the ground truth for the training set was established:

As mentioned above, there isn't a "training set" in the AI/ML sense for this type of device.
The design of the assay (primers, probes) would have been based on established scientific knowledge of carbapenemase gene sequences and validated against known reference strains with confirmed gene presence/absence through sequencing and other molecular characterization techniques. This iterative process of design and validation ensures the assay's ability to detect the target genes accurately.

Summary

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Image /page/0/Picture/0 description: The image contains the logos of the Department of Health and Human Services and the Food and Drug Administration (FDA). The Department of Health and Human Services logo is on the left, and the FDA logo is on the right. The FDA logo includes the letters "FDA" in a blue square, followed by the words "U.S. FOOD & DRUG ADMINISTRATION" in blue text.

August 29, 2019

Check-Points Health B.V. Pieter Vos Chief Technical Officer Binnenhaven 5 6709 PD Wageningen The Netherlands

Re: K190613

Trade/Device Name: BD MAX Check-Points CPO Regulation Number: 21 CFR 866.1640 Regulation Name: Antimicrobial susceptibility test powder Regulatory Class: Class II Product Code: POC, OOI Dated: March 6, 2019 Received: March 18, 2019

Dear Pieter Vos:

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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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

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requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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 https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

for

Ribhi Shawar, Ph.D. (ABMM) Chief. General Bacteriology and Antimicrobial Susceptibility Branch Division of Microbiology Devices OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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DEPARTMENT OF HEALTH AND HUMAN SERVICES Form Approved: OMB No. 0910-0120
Food and Drug Administration	Expiration Date: 06/30/2020
Indications for Use	See PRA Statement below.
510(k) Number (if known)
K190613
Device Name

BD MAX™ Check-Points CPO

Indications for Use (Describe)

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

FORM FDA 3881 (7/17)

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510(k) Summary

Image /page/3/Picture/1 description: The image shows the logo for Check-Points, a company specializing in rapid molecular detection. The logo features a cluster of nine purple dots arranged in a diamond shape on the left. To the right of the dots is the company name, "Check-Points," in a bold, sans-serif font. Below the company name, in smaller font, is the tagline "rapid molecular detection."

1. Applicant:

Check-Points Health B.V. Binnenhaven 5 6709 PD Wageningen The Netherlands

2. Contact Person:

Pieter Vos, CTO E-mail: pietervos@check-points.com Phone: +31 317 45 39 08 Mobile: +31 622 40 07 80

3. Summary Preparation Date:

August 22, 2019

4. Device Name and Classification:

Trade Name (proprietary name): BD MAX™ Check-Points CPO

Common Name (usual name): BD MAX™ Check-Points CPO

Classification: Class II

Product code: POC (System, nucleic acid amplification test, DNA, antimicrobial resistance marker, direct specimen)

Panel: Microbiology (83)

Regulation section: 21 CFR 866.1640 (Antimicrobial susceptibility test powder)

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Predicate Device Name	Manufacturer	Predicate 510(k) Number
Xpert® Carba-R Assay	Cepheid, Inc.	K160901

5. Substantial Equivalence Information:

Comparison with Predicate:

	Device	Predicate
Name	BD MAX™ Check-PointsCPO	Xpert® Carba-R Assay
Intended Use	Qualitative in vitrodiagnostic real-time PCRtest for detection ofcarbapenemase genesfrom rectal swabs	Same
Organisms andResistance MarkersDetected	KPCNDMVIMOXA-48IMP	SameSameSameSameSame
Analyte	DNA	Same
TechnologicalPrinciples	Fully-automated nucleicacid amplification (DNA);real-time PCR	Same
Specimen Type	Rectal swabs	Same
Sample Preparation	Automated by Instrument	Same
Instrumentation	BD MAX System	GeneXpert System
Interpretation ofResults	Automated by Instrument	Same
Controls	Sample ProcessingControl (SPC)	SameProbe Check control(PCC)
Time to Result	3 hours	1 hour

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6. Device Description:

The BD MAX Check-Points CPO Assay detects the presence of carbapenemase genes in Gram-negative bacteria and includes an internal Sample Processing Control.

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7. Intended use(s):

The BD MAX Check-Points CPO Assay performed on the BD MAX System is a qualitative, automated in vitro diagnostic real-time PCR test designed for the detection and differentiation of the carbapenemase genes blayow. blaviw/blamp and blaoxa-48, that are associated with carbapenem non-susceptibility in Gram-negative bacteria. The assay does not distinguish between the blayMand blaimp genes.

Testing is performed on rectal swabs from patients at risk for intestinal colonisation with carbapenem non-susceptible bacteria. This test is intended for use in conjunction with clinical presentation, laboratory findings, and epidemiological information. Results of this test should not be used as the sole basis for patient management decisions. Concomitant cultures are necessary to recover organisms for epidemiological typing, antimicrobial susceptibility testing, and for further confirmatory bacterial identification.

Special Conditions for Use Statement: For prescription use

Special Instrument Requirements: BD MAX System

8. Indication for use(s):

Patients at risk for intestinal colonisation with carbapenem non-susceptible bacteria.

9. Performance Characteristics:

Clinical performance characteristics of the BD MAX Check-Points CPO Assay were determined in a multi-site investigational study and a study involving contrived specimens. The investigational study involved a total of five (5) geographically diverse clinical centers where rectal swab specimens were collected as part of routine patient care, enrolled into the trial, and tested with the BD MAX Check-Points CPO Assay. Specimens were obtained from patients at risk for intestinal colonization with carbapenem non-susceptible bacteria. The reference method was a bacterial culture for recovery of non-susceptible isolates from the rectal swab specimens followed by detection of antibiotic resistance genes by PCR and sequencing. The bacterial culture comprised both direct plating on chromID Carba and chromID OXA48 as well as over-night enrichment in MacConkey broth followed by plating on MacConkey agar with a 10 ug meropenem disc. For

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contrived specimens, well-characterized strains were spiked into unique negative rectal swab matrix near the LoD and analyzed by BD MAX Check-Points CPO. In addition, the strains were analyzed by PCR and sequencing.

A total of 1486 prospective specimens and 166 contrived specimens were eligible for the clinical evaluation. 13 of 1486 prospective specimens were unreportable leaving 1473 prospective specimens to calculate clinical performance. Tables 1 through 4 describe the performance characteristics of the BD MAX Check-Points CPO Assay that were observed during the clinical trial.

Non-Reportable Rate

Of all specimens evaluated. 1.9% (28/1486) and 0% (0/166) were initially reported as Unresolved/Indeterminate/Inconclusive for the prospective and contrived specimens, respectively. Following a valid repeat test for 17 of 28 specimens (11 were not repeated), 0.1% (2/1475) and 0% remained Unresolved for the prospective and contrived specimens, respectively.

Performance Results with KPC producing organisms

The clinical performance for KPC in the prospective study and contrived study is summarized in Table 1 below.

KPC	Prospective						Contrived
	MacConkeyPCR/Sequencing		chromIDPCR/Sequencing		MacConkey +chromIDPCR/Sequencing		PCR/Sequencing
		POS	NEG	POS	NEG	POS	NEG	POS	NEG
BD MAXCheck-PointsCPO	POS	23	10	28	5	30	3	30	0
	NEG	3	1437	1	1439	4	1436	0	136
Sensitivity/PPA(95% CI)		88.5% (71.0-96.0%)		96.6% (82.8-99.4%)		88.2% (73.4-95.3%)		100% (88.6-100%)
Specificity/NPA(95% CI)		99.3% (98.7-99.6%)		99.7% (99.2-99.9%)		99.8% (99.4-99.9%)		100% (97.3-100%)

Table 1. KPC – Overall Performance

Performance Results with VIM and IMP producing organisms

The clinical performance for VIM/IMP in the prospective study and contrived study is summarized in Table 2 below.

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Table 2. VIM/IMP – Overall Performance
	Prospective

		Prospective							Contrived
VIM/IMP		MacConkeyPCR/Sequencing		chromIDPCR/Sequencing		MacConkey +chromIDPCR/Sequencing		PCR/Sequencing
		POS	NEG	POS	NEG	POS	NEG	POS	NEG
BD MAXCheck-PointsCPO	POS	5	12	4	13	6	11	50	0
	NEG	0	1456	2	1454	2	1454	2	114
Sensitivity/PPA(95% CI)		100% (56.6-100%)		66.7% (30.0-90.3%)		75.0% (40.9-92.9%)		96.2% (87.0-98.9%)
Specificity/NPA(95% CI)		99.2% (98.6-99.5%)		99.1% (98.5-99.5%)		99.2% (98.7-99.6%)		100% (96.7-100%)

Performance Results with OXA48 producing organisms

The clinical performance for OXA-48 in the prospective study and contrived study is summarized in Table 3 below.

Table 3. OXA48 – Overall Performance

OXA-48		Prospective						Contrived
		MacConkeyPCR/Sequencing		chromIDPCR/Sequencing		MacConkey +chromIDPCR/Sequencing		PCR/Sequencing
		POS	NEG	POS	NEG	POS	NEG	POS	NEG
BD MAXCheck-PointsCPO	POS	20	20	25	15	25	15	30	0
	NEG	1	1432	0	1433	1	1432	0	136
Sensitivity/PPA(95% Cl)		95.2% (77.3-99.2%)		100% (86.7-100%)		96.2% (81.1-99.3%)		100% (88.6-100%)
Specificity/NPA(95% CI)		98.6% (97.9-99.1%)		99.0% (98.3-99.4%)		99.0% (98.3-99.4%)		100% (97.3-100%)

Performance Results with NDM producing organisms

The clinical performance for NDM in the prospective study and contrived study is summarized in Table 4 below.

			Table 4. NDM - Overall Performance
--	--	--	------------------------------------

NDM		Prospective						Contrived
		MacConkeyPCR/Sequencing		chromIDPCR/Sequencing		MacConkey +chromIDPCR/Sequencing		PCR/Sequencing
		POS	NEG	POS	NEG	POS	NEG	POS	NEG
BD MAXCheck-PointsCPO	POS	1	1	1	1	1	1	30	0
	NEG	0	1471	0	1471	0	1471	0	136
Sensitivity/PPA(95% CI)		100% (20.7-100%)	100% (20.7-100%)	100% (20.7-100%)	100% (20.7-100%)	100% (88.6-100%)
Specificity/NPA(95% CI)		99.9% (99.6-100%)	99.9% (99.6-100%)	99.9% (99.6-100%)	99.9% (99.6-100%)	100% (97.3-100%)

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Analytical Inclusivity

A variety of BD MAX Check-Points CPO target organisms and carbapenemase gene variants were included in this study. Strain selection criteria included prevalence and clinical importance. Ninety-three (93) strains were tested, including strains from public collections and well-characterized clinical isolates.

Inclusivity testing included 16 different species and 17 KPC strains representing 2 variants, 17 VIM strains representing 7 variants, 18 IMP strains representing 7 variants, 20 OXA48-type strains representing 7 variants, 17 NDM strains representing 4 variants and 4 strains containing two carbapenemase target genes. The strains were tested in triplicate at 3x LoD (Limit of Detection). The BD MAX Check-Points CPO correctly identified 90 of the 93 strains tested upon initial testing. Three strains, an Enterobacter cloacae with IMP-34, a Pseudomonas aeruginosa with IMP-4 and a Klebsiella pneumoniae with NDM-1 were detected when re-tested at 10x LoD. A summary is presented in Table 5 below and compared to the in silico prediction results. A total of 97 target genes were tested in a total of 93 strains (4 strains had two target genes).

		Inclusivity Results
Target	No. oftargetgenes	Variantsdetected	Variantsnotdetected	in silico Prediction
KPC	17	KPC-2, 3	-	KPC-2-37
VIM	19	VIM-1, 2, 4,19, 26, 27, 31	-	VIM-1-6, -8-52, -54, -56-60
IMP	20	IMP-1, 3, 4, 7,8, 26, 34,	-	IMP-1-4, 6-8, 10, 19, 20, 23-26, 30,34, 38, 40, 42-43, 51, 52, 55, 59-61, 66, 70, 73, 76-80
OXA-48	22	OXA-48, 162,163, 181, 204,232, 244	-	OXA-48, 162, 163, 181, 204, 232,244, 245, 370, 405, 438, 439, 484,505, 517, 519, 566
NDM	19	NDM-1, 5, 6, 7	-	NDM-1-24

Table 5. BD MAX Check-Points CPO Inclusivity Results versus in silico Prediction

In summary, all variants tested and predicted detected by in silico analysis were detected by BD MAX Check-Points CPO. In addition, IMP-7 and OXA-163 not predicted detected by in silico analysis were detected by BD MAX Check-Points CPO. IMP-43, -51 and -73 have the same primer and probe target sequences as IMP-7 and OXA-438-439 have the same primer and probe target sequences as OXA-163 and therefore also expected detected by BD MAX Check-Points CPO Assay.

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Analytical Sensitivity (Limit of Detection)

The analytical sensitivity (Limit of Detection or LoD) for the BD MAX Check-Points CPO was determined using two strains for each carbapenemase gene, i.e. 10 strains. Bacterial cell suspensions of each strain were prepared and quantified from culture prior to inclusion in this study. A total of six 2-fold serial dilutions in negative rectal matrix were prepared for all strains at test concentrations expected to comprise the LoD for each carbapenemase target gene. Replicates of 10 of each test concentration were evaluated using 3 BD MAX instruments and 3 lots of reagents and consumables to estimate the LoD. For this study, the estimated LoD was defined as the lowest concentration of target cells at which 10/10 replicates gave a positive test result. The LoD was then confirmed by testing 20 replicates for each strain at the estimated LoD. Analytical sensitivity (LoD), defined as the lowest concentration at which ≥ 95% of all replicates are expected to test positive, ranged from 144 to 4774 CFU/mL of Sample Buffer after dispensing rectal swab specimen into the Sample Buffer Tube.

Target	Strain	Species	CFU/mL	%
KPC	CP254	Klebsiella pneumoniae	2005	95%
	CP365	Klebsiella pneumoniae	3560	100%
VIM	CP260	Pseudomonas aeruginosa	159	100%
	CP433	Enterobacter cloacae	520	95%
IMP	CP253	Escherichia coli	319	100%
	CP149	Klebsiella pneumoniae	144	95%
OXA	CP258	Klebsiella pneumoniae	229	95%
	CP411	Escherichia coli	902	95%
NDM	CP259	Klebsiella pneumoniae	4774	100%
	CP184	Escherichia coli	4492	95%

Table 6. BD MAX Check-Points CPO Limit of Detection for Individual Targets
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Analytical Specificity

The BD MAX Check-Points CPO Assay was performed on samples containing phylogenetically related species and other organisms likely to be found in rectal swab specimens. In addition, species were tested typically containing the BD MAX Check-Points CPO carbapenemase target genes, but having either no or a different carbapenemase gene, other ß-lactamase genes or other antibiotic resistance determinants. The bacterial cells were seeded into negative rectal swab matrix at a concentration of ~ 5 x 10° cells/mL. Overall, 26 organisms were tested in 3 replicates and are listed in Table 7. All organisms tested negative.

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StrainID	Species	Reference	B-lactamase gene
CP-575	Campylobacter jejuni	CCUG-41359	None
CP-521	Citrobacter freundii	N/A	CTX-M9 ESBL
CP-338	Citrobacter braakii	N/A	GESCarbapenemase
CP-568	Corynebacterium diphtheriae	CCUG-37874	None
CP-484	Enterobacter aerogenes	N/A	None
CP-034	Enterobacter cloacae	N/A	CTX-M9 ESBL
CP-573	Enterococcus casseliflavus	CCUG-55879	None
CP-574	Enterococcus faecalis	CCUG-9997	None
CP-048	Escherichia coli	N/A	CTX-M1 ESBL
CP-576	Helicobacter pylori	CCUG-17874	None
CP-058	Klebsiella oxytoca	N/A	CTX-M9 ESBL
CP-012	Klebsiella pneumonia	N/A	SHV-ESBL
CP-570	Listeria monocytogenes	CCUG-33548	None
CP-357	Pseudomonas aeruginosa	N/A	PER ESBL
CP-132	Salmonella typhimurium	N/A	pAmpC
CP-519	Raoultella sp.	N/A	SHV & CTX-M9ESBL
CP-571	Staphylococcus aureus	CCUG-9128	None
CP-250	Serratia marcescens	N/A	None
CP-009	Stenotrophomonas maltophilia	N/A	SHV & CTX-M9ESBL; pAmpC
CP-284	Acinetobacter baumannii	N/A	OXA-23Carbapenemase
CP-503	Morganella morganii	N/A	None
CP-319	Providencia stuartii	N/A	VEB ESBL
CP-567	Providencia alcalifaciens	CCUG-6325	None
CP-569	Streptococcus agalactiae	CCUG-29780	None
CP-052	Proteus mirabilis	N/A	pAmpC
CP-440	Acinetobacter baumannii	N/A	OXA-58Carbapenemase

Table 7. Organisms Tested to Determine BD MAX Check-Points CPO Specificity

N/A: Strain from in-house strain collection with no reference number available

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Interfering Substances

Twenty-nine (29) biological and chemical substances that may occasionally be present in rectal swab specimens were evaluated for potential interference with the BD MAX Check-Points CPO Assay and are listed in Table 8. All substances were evaluated at a test concentration of 0.25% w/v (2.5 mg/mL) in negative rectal swab matrix. Test specimens included negative rectal swab matrix seeded with target organisms at 3x LoD (positive specimens) or not seeded (negative specimens). For each substance 6 positive and 6 negative specimens were tested. Results demonstrated no reportable interference with any of the substances tested (refer to Table 8).

Oils & fattyacids	Metal salts	Antibiotics	Painkillers
Stearic acid	Ba2SO4	Cephalexin	Naproxen
Palmitic acid	CaCO3	Ciprofloxacin	Benzocaine
Mineral Oil	Al(OH)3	Polymyxin B	Phenylephrine
Simethicone	Mg(OH)2	Bacitracin	Bismuthsubsalicylate
Cholesterol		Neomycin
Alcohols	Histamineantagonists	Surfactants	Remaining
Resorcinol	Famotidine	Nonoxynol-9	Hydrocortisone
Ethanol	Omeprazole	Benzalkoniumchloride	LoperamideHydrochloride
	Cimetidine		Nystatin
			Sennosides

Table 8. Substances not Interfering with BD MAX Check-Points CPO

Inter-lab reproducibility

The inter-lab reproducibility for the BD MAX Check-Points CPO Assay was determined by analyzing one strain per target spiked into negative rectal swab matrix in 2 different concentrations (1.5x LoD and 3x LoD), non-target strain spiked into negative rectal swab matrix and negative rectal swab matrix at 3 different sites by 2 operators using 1 lot during 5 days.

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	KPC		NDM		OXA-48		VIM/IMP
	+	-	+	-	+	-	+	-
1.5x LoD	100%(60/60)		98.3%(59/60)		100%(60/60)		97.5%(117/120)
(95% CI)	(94.0-100%)		(91.1-99.7%)		(94.0-100%)		(92.9-99.1%)
3x LoD	100%(60/60)		100%(60/60)		100%(60/60)		99.2%(119/120)
(95% CI)	(94.0-100%)		(94.0-100%)		(94.0-100%)		(95.4-99.9%)
Negatives		100%(100/100)		100%(100/100)		100%(100/100)		100%(100/100)
(95% CI)		(96.3-100%)		(96.3-100%)		(96.3-100%)		(96.3-100%)

Table 9. Inter-lab Reproducibility Results for BD MAX Check-Points CPO

In summary, the inter-lab reproducibility ranged from 100-100%, 97.5-100% and 99.2-100% for Negatives, 1.5x LoD and 3x LoD, respectively.

Inter-lot reproducibility

The inter-lot reproducibility for the BD MAX Check-Points CPO Assay was determined by analyzing one strain per target spiked into negative rectal swab matrix in 2 different concentrations (1.5x LoD and 3x LoD), non-target strain spiked into negative rectal swab matrix and negative rectal swab matrix at 1 site by 2 operators using 3 lots during 5 days.

	KPC		NDM		OXA-48		VIM/IMP
	+	-	+	-	+	-	+	-
1.5x LoD	100%(60/60)		100%(60/60)		100%(60/60)		99.2%(119/120)
(95% CI)	(94.0-100%)		(94.0-100%)		(94.0-100%)		(95.4-99.9%)
3x LoD	100%(60/60)		100%(60/60)		100%(60/60)		100%(120/120)
(95% CI)	(94.0-100%)		(94.0-100%)		(94.0-100%)		(96.9-100%)
Negatives		100%(90/90)		100%(90/90)		100%(90/90)		100%(90/90)
(95% CI)		(95.9-100%)		(95.9-100%)		(95.9-100%)		(95.9-100%)

Table 10. Inter-lot Reproducibility Results for BD MAX Check-Points CPO

In summary, the inter-lot reproducibility ranged 100-100%, 100-100% and 99.2-100% for Negatives, 1.5x and 3x LoD, respectively.

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Intra-lab reproducibility

The intra-lab reproducibility was determined by analyzing one strain per target spiked into neqative rectal swab matrix in 2 different concentrations (1.5x LoD and 3x LoD), non-target strain spiked into negative rectal swab matrix and neqative rectal swab matrix at 1 site by 2 operators using 1 lot during 12 days.

	KPC			NDM		OXA-48		VIM/IMP
	+	-	+	-	+	-	+	-
1.5x LoD	100%(48/48)		100%(48/48)		97.9%(47/48)		99.0%(95/96)
(95% CI)	(92.6-100%)		(92.6-100%)		(89.1-99.6%)		(94.3-99.8%)
3x LoD	97.9%(47/48)		100%(48/48)		100%(48/48)		100%(96/96)
(95% CI)	(89.1-99.6%)		(92.6-100%)		(92.6-100%)		(96.2-100%)
Negatives		100%(72/72)		100%(72/72)		100%(72/72)		100%(72/72)
(95% CI)		(94.9-100%)		(94.9-100%)		(94.9-100%)		(94.9-100%)

Table 11. Intra-lab Reproducibility Results for BD MAX Check-Points CPO

In summary, the intra-lab reproducibility ranged from 100-100%, 97.9-100% and 97.9-100% for Negatives, 1.5x and 3x LoD, respectively.

Carry-over contamination

Carry-over contamination was assessed by testing negative specimens together with positive specimens containing a high load of bacteria carrying the carbapenemase resistance genes KPC, OXA48, NDM and VIM or IMP. Positions of negative and positive specimens were alternated to maximize the possibility for carry-over contamination. Negative rectal swab matrix was used for negative specimens, and to prepare positive specimens by seeding matrix with target organisms at a concentration of 5 x 106 CFU/mL. No positive calls were found for a total of 166 negative specimens.

Mixed Infection / Competitive interference

No interference was observed from testing of thirteen (13) specimens containing one KPC, VIM, IMP, OXA-48, or NDM target from strains with known LoD spiked at 2x LoD and one or two other target organism(s) spiked at ~1x106 CFU/mL into negative rectal swab matrix.

10. Conclusion:

The performance characteristics summarized above demonstrate that BD MAX Check-Points CPO is safe and effective for its intended use and is substantially equivalent to the predicate device.

Regulation Number and Section

§ 866.1640 Antimicrobial susceptibility test powder.

(a)
Identification. An antimicrobial susceptibility test powder is a device that consists of an antimicrobial drug powder packaged in vials in specified amounts and intended for use in clinical laboratories for determining in vitro susceptibility of bacterial pathogens to these therapeutic agents. Test results are used to determine the antimicrobial agent of choice in the treatment of bacterial diseases.(b)
Classification. Class II (performance standards).