(90 days)
Not Found
No
The description focuses on the immunofluorescence assay and proprietary detection technology, with no mention of AI or ML being used for image analysis or result interpretation. The results are interpreted by "MultiPath applications software" which is not described as using AI/ML.
No
The device is a diagnostic tool designed to detect a biomarker associated with Bacillus anthracis, aiding in the diagnosis of inhalation anthrax. It does not provide treatment or therapy.
Yes
The device is explicitly stated to "aid in the diagnosis of inhalation anthrax" and a "positive SensiTox B. anthracis Toxin Test result is presumptively diagnostic for B. anthracis infection."
No
The device description clearly states that the SensiTox B. anthracis Toxin Test is run on the "MultiPath Analyzer," which is a piece of hardware that processes the cartridge, heats the sample, moves the cartridge, uses magnets, and performs digital imaging. The software is part of a larger hardware system.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use: The "Intended Use / Indications for Use" section explicitly states that the device is "to aid in the diagnosis of inhalation anthrax" and is for the "rapid, qualitative detection of lethal factor, a biomarker associated with Bacillus anthracis)." This clearly indicates its use in examining specimens from the human body to provide information for diagnosis.
- Specimen Type: The device uses "whole blood collected with dipotassium EDTA anticoagulant by venipuncture," which is a human specimen.
- Purpose: The purpose is to detect a biomarker (lethal factor) associated with a disease (inhalation anthrax) to aid in diagnosis.
- Device Description: The description details an "immunofluorescence assay" that detects a substance in a human specimen.
These characteristics align directly with the definition of an In Vitro Diagnostic device.
N/A
Intended Use / Indications for Use
The SensiTox B. anthracis Toxin Test for use with the MultiPath Analyzer, is a qualitative immunofluorescence assay to aid in the diagnosis of inhalation anthrax. The test is intended for the rapid, qualitative detection of lethal factor, a biomarker associated with Bacillus anthracis (B. anthracis). The test can be used with whole blood collected with dipotassium EDTA anticoagulant by venipuncture. This test is indicated for testing samples from individuals who have signs and symptoms consistent with inhalation anthrax and a likelihood of exposure to B. anthracis. A positive SensiTox B. anthracis Toxin Test result is presumptively diagnostic for B. anthracis infection. Diagnosis of B. anthracis infection must be made in conjunction with medical history, likelihood of exposure, signs, and symptoms of disease, as well as other laboratory evidence. The definitive identification of B. anthracis from blood samples requires additional testing and confirmation procedures in consultation with public health or other authorities for whom reports are required. Testing should be performed and reported in accordance with current guidelines provided by the appropriate public health authorities. The level of lethal factor present in blood from individuals with early systemic infection is unknown. Negative results do not preclude infection with the biothreat microbial agents targeted by the device and should not be used as the sole basis for diagnosis, treatment, or other patient management decisions.
Laboratories performing the SensiTox B. anthracis Toxin Test must have the appropriate biosafety equipment, personal protective equipment (PPE), containment facilities, and personnel trained in the safe handling of clinical specimens potentially containing B. anthracis.
The SensiTox B. anthracis Toxin Test is for prescription use only.
This assay is not FDA-cleared or approved for testing blood or plasma donors.
Product codes
QUU
Device Description
The SensiTox B. anthracis Toxin Test, run on the MultiPath Analyzer, detects lethal factor in venous whole blood samples using an immunofluorescence assay and the proprietary MultiPath detection technology.
A whole blood specimen, collected in dipotassium EDTA, from individuals with signs and symptoms consistent with inhalation anthrax and a likelihood of exposure, is used for the test. The blood sample is added directly to the SensiTox B. anthracis Cartridge, a single use consumable that contains all the reagents required to run the test. The Cartridge is loaded onto the MultiPath Analyzer for processing through the steps of the assay.
Once loaded onto the Analyzer, the barcodes on the cartridge that identify the test type and associated test specific information (manufacturer installed barcode) and sample (laboratory affixed barcode) are read. The cartridge is moved to the fluidics station where it is first heated to 35°C. The sample is then split into 3 equal aliquots in 3 distribution wells within the cartridge. The sample aliquots flow from the distribution wells to the reagent wells containing target-specific antibody conjugated fluorescent and magnetic particles in the form of lyophilized beads. Upon contact with the sample, the lyophilized beads rehydrate and the reaction mixtures flow into the imaging wells, the bottoms of which are coated with a dye cushion reagent. Upon contact with the reagents, the dye-cushion dissolves forming a dense opaque aqueous layer that separates the sample and reagents from the bottom optical surface of the Imaging Well. In the upper assay layer, the toxins, if present, bind to the magnetic and fluorescent particles tethering them together. The cartridge is incubated for 12 minutes to allow the reaction to take place and then is moved to the magnetics station. At the magnetics station, the imaging well is placed over permanent magnets that draw the magnetic particles and any fluorescent particles that are tethered to them via the target molecules through the dye-cushion layer, depositing them on the bottom imaging surface. The captured fluorescent particles are imaged and quantified using nonmagnified digital imaging.
The Analyzer can be run in batch mode or by random access. Up to 20 cartridges can be loaded onto the Analyzer in parallel. The first result is reported in approximately 21 minutes of loading the cartridge onto the Analyzer with subsequent results being reported in 2.5-minute increments. The results are interpreted using the MultiPath applications software as valid or invalid, and if valid, the results are reported as Lethal Factor detected. Results are displayed on the instrument touch screen and can be printed.
Mentions image processing
Yes, "The captured fluorescent particles are imaged and quantified using nonmagnified digital imaging."
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Not Found
Indicated Patient Age Range
Not Found
Intended User / Care Setting
Laboratories performing the SensiTox B. anthracis Toxin Test must have the appropriate biosafety equipment, personal protective equipment (PPE), containment facilities, and personnel trained in the safe handling of clinical specimens potentially containing B. anthracis.
The SensiTox B. anthracis Toxin Test is for prescription use only.
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Reproducibility: Evaluated at 3 sites over the course of 5 non-consecutive days by 2 operators per site each day. Three lots of cartridges were tested. Samples comprised of whole blood spiked with two concentrations of recombinant Lethal Factor – low positive (1.5X LoD), moderate positive (3X LoD), and negative (unspiked). Each operator mixed a blinded sample with whole blood prescreened and known to be negative for Lethal Factor and tested in triplicate.
Analytical Reactivity (Inclusivity): 29 B. anthracis strains containing the wildtype pXO1 plasmid and representing geographical diversity of clinically relevant strains were tested. Supernatants from mid-log phase cultures were isolated, sterilized, and the LF content quantified by ELISA. Supernatants from each strain were spiked into venous K2EDTA anticoagulated whole blood at 3X LoD (150 pg/mL) and tested in triplicate.
Analytical Specificity – Cross Reactivity: Bacterial, viral, protozoan, and fungal pathogens were typically tested at 1x10^6 CFU/mL and viral pathogens at 1x10^5 PFU/mL by addition to pre-screened K2EDTA human venous whole blood. Each pathogen was tested in triplicate.
Analytical Specificity – Microbial Interference: Bacterial, fungal, and protozoan pathogens were typically tested at 1x10^6 CFU/mL and viral pathogens at 1x10^5 PFU/mL by addition to pre-screened K2EDTA human venous whole blood containing 150 pg/mL of recombinant Lethal Factor (3X LoD). Each pathogen was tested in triplicate.
Interfering Substances: Endogenous and exogenous substances were tested in K2EDTA anticoagulated whole blood unspiked and spiked with 150 pg/mL (3X LoD) of recombinant Lethal Factor and run in triplicate.
Hook Effect: Recombinant LF was diluted to concentrations ranging from 50 pg/mL to 50 µg/mL in K₂EDTA anticoagulated venous whole blood and three replicates of each dilution were tested.
Clinical Performance Evaluation:
- Negative Percent Agreement (NPA) arm: 325 residual whole blood specimens collected in K₂EDTA for routine hematology analysis from a single clinical site. 318 specimens were included in data analysis and tested at two sites.
- Positive Percent Agreement (PPA) arm: 126 subjects presenting with fever and flu-like symptoms were enrolled for the collection of fresh venous whole blood specimens. 105 eligible samples were included. Patient specimens were tested at a single site. Additionally, contrived specimens prepared from prospectively collected blood specimens and containing either native Lethal Factor (LF) contained in cell supernatants at 75 pg/mL (1.5X LoD) and 250 pg/mL (5X LoD) or recombinant LF at concentrations of 75 pg/mL, and 5 μg/mL were prepared and tested blinded at a second site.
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Limit of Detection (LoD)
The LoD established for Lethal Factor is 50 pg/mL.
Reproducibility
Evaluated at 3 sites over 5 non-consecutive days by 2 operators/site.
Sample Size: 270 samples (90 per site), tested in triplicate.
Overall reproducibility: 98.9%.
3 incorrect results (2 low positive, 1 moderate positive) generated negative results.
Accuracy by site:
Site 1: 100%
Site 2: 97.8% (2 false negatives)
Site 3: 98.9% (1 false negative)
Analytical Reactivity (Inclusivity)
29 B. anthracis strains were tested at 3X LoD (150 pg/mL).
All 29 B. anthracis strains were detected.
In silico analysis: 299/303 (98.7%) unique B. anthracis strains in NCBI db had identical amino acid sequences to those tested.
Analytical Specificity – Cross Reactivity
Tested bacterial, viral, protozoan, and fungal pathogens.
No cross-reactivity observed, except for two B. cereus strains (G9241 and 03BB102) which contain the extrachromosomal plasmid pXO1 that harbors the gene for Lethal Factor. These were detected as expected.
Analytical Specificity – Microbial Interference
Tested bacterial, viral, fungal, and protozoan pathogens in whole blood containing 150 pg/mL of recombinant Lethal Factor (3X LoD).
None of the organisms tested interfered with the SensiTox B. anthracis Toxin Test; all replicates generated detected results.
Interfering Substances
Tested endogenous (Glucose, Hemoglobin, Human Immunoglobulins (IgG), Triglycerides, Cholesterol, Human Serum Albumin, Bilirubin, Human Anti-Mouse Antibodies) and exogenous substances (Acetaminophen, Acid-citrate-dextrose, Albuterol (Salbutamol), Amoxicillin, Artemisinin, Ascorbic acid, Aspirin, Biothrax, Cefotaxime, Chloroquine, Ciprofloxacin, Cromolyn sodium, Doxycycline, EDTA, Erythromycin, Flunisolide (Flovent), Gentamicin sulfate, Heparin, Ibuprofen, Malarone (Atovaquone), Mefloquine, N-acetylcysteine, Naproxen sodium, Oseltamivir (Tamiflu), Ribavirin, Rifampin, Sodium citrate, Sodium polyanetholesulfonate, Streptomycin, Sulfamethoxazole, Tetracycline, Tobramycin, Trimethoprim).
None of the substances tested interfered with the SensiTox B. anthracis Toxin Test.
Hook Effect
Tested recombinant LF concentrations from 50 pg/mL to 50 µg/mL.
All concentrations greater than 50 pg/mL yielded 3/3 detected results. At 50 pg/mL, 1/3 replicates yielded "not detected", which is consistent with the LoD.
No hook effect was observed for qualitative data between 50 pg/mL and 50 µg/mL LF.
Clinical Performance Evaluation
NPA Study (Residual whole blood specimens):
Sample Size: 318 residual whole blood specimens.
Expected Neg: 318
SensiTox B. anthracis Toxin Test Neg: 318
Observed Pos: 0
Negative Percent Agreement (NPA): 100.0% (95% C.I.: 98.8% - 100.0%)
PPA Study (Prospective arm specimens):
Sample Size: 105 contrived specimens (from 210 expected results)
Expected Pos: 105
SensiTox B. anthracis Toxin Test Pos: 101
SensiTox B. anthracis Toxin Test Neg: 4 (all at 75 pg/mL LF (1.5X LoD), confirmed positive when retested).
Positive Percent Agreement (PPA): 96.2%* (95% C.I.: 90.6% - 98.5%)
Negative Percent Agreement (NPA) for 105 expected negative: 100.0% (96.5% - 100.0%)
Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)
Negative Percent Agreement (NPA) for residual whole blood specimens: 100.0% (95% C.I.: 98.8% - 100.0%)
Positive Percent Agreement (PPA) for prospective arm specimens: 96.2%* (95% C.I.: 90.6% - 98.5%)
Negative Percent Agreement (NPA) for prospective arm specimens: 100.0% (96.5% - 100.0%)
Predicate Device(s): If the device was cleared using the 510(k) pathway, identify the Predicate Device(s) K/DEN number used to claim substantial equivalence and list them here in a comma separated list exactly as they appear in the text. List the primary predicate first in the list.
InBios International, Inc. Active Anthrax Detect Plus Rapid Test (DEN220044)
Reference Device(s): Identify the Reference Device(s) K/DEN number and list them here in a comma separated list exactly as they appear in the text.
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information for the subject device only (e.g. presence / absence, what scope was granted / cleared under the PCCP, any restrictions, etc).
Not Found
N/A
0
November 20, 2023
Image /page/0/Picture/1 description: The image contains the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which is a blue square with the letters "FDA" in white. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.
First Light Diagnostics, Inc. Joanne Spadoro Chief Executive Officer 2 Omni Way Chelmsford. Massachusetts 01824
Re: K232545
Trade/Device Name: The SensiTox B. anthracis Toxin Test Regulation Number: 21 CFR 866.3046 Regulation Name: Simple In Vitro Diagnostic Device For The Detection Of Secreted Proteins From Bacillus Species (Spp.) In Human Clinical Samples Regulatory Class: Class II Product Code: QUU Dated: August 22, 2023 Received: August 22, 2023
Dear Joanne Spadoro:
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 (the 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 available 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.
Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).
1
Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review. the OS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).
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 Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safetyreporting-combination-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 Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 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,
Noel J. Gerald -S
Noel J. Gerald, Ph.D. Branch Chief Bacterial Respiratory and Medical Countermeasures Branch Division of Microbiology Devices OHT7: Office of In Vitro Diagnostics Office of Product Evaluation and Quality Center for Devices and Radiological Health
2
Indications for Use
510(k) Number (if known) K232545
Device Name SensiTox B. anthracis Toxin Test
Indications for Use (Describe)
The SensiTox B. anthracis Toxin Test for use with the MultiPath Analyzer, is a qualitative immunofluorescence assay to aid in the diagnosis of inhalation anthrax. The test is intended for the rapid, qualitative detection of lethal factor, a biomarker associated with Bacillus anthracis). The test can be used with whole blood collected with dipotassium EDTA anticoagulant by venipuncture. This testing samples from individuals who have signs and symptoms consistent with inhalation anthrax and a likelihood of exposure to B. anthracis. A positive SensiTox B. anthracis Toxin Test result is presumptively diagnostic for B. anthracis infection. Diagnosis of B. anthracis infection must be made in conjunction with medical history, likelihood of exposure, signs, and symptoms of disease, as well as other laboratory evidence. The definitive identification of B. anthracis from blood samples additional testing and confirmation procedures in consultation with public health or other authorities for whom reports are required. Testing should be performed and reported in accordance with current guidelines provided by the appropriate public health authorities. The level of lethal factor present in blood from individuals with early systemic infection is unknown. Negative results do not preclude infection with the biothreat microbial agents targeted by the device and should not be used as the sole basis for diagnosis, treatment, or other patient management decisions.
Laboratories performing the SensiTox B. anthracis Toxin Test must have the appropriate biosafety equipment, personal protective equipment (PPE), containment facilities, and personnel trained in the safe handling of clinical specimens potentially containing B. anthracis.
The SensiTox B. anthracis Toxin Test is for prescription use only.
This assay is not FDA-cleared or approved for testing blood or plasma donors.
| 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) |
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3
510(k) Summary
August 21, 2023
The summary of the 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92.
Contact Details
| Sponsor: | First Light
Diagnostics, Inc.
2 Omni Way
Chelmsford, MA 01824 |
|----------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Correspondent: | Joanne Spadoro, Ph.D.
President and CEO
First Light Diagnostics, Inc.
2 Omni Way
Chelmsford, MA 01824
Phone: (781) 271-0112, extension 224
Email: joanne@firstlightdx.com |
Device
| Device Trade Name: | SensiTox® B. anthracis Toxin Test |
|---|---|
| Common Name: | B. anthracis Toxin Test |
| Classification Name: | Class II |
| Regulation Number: | 866.3046 |
| Product Code: | QUU |
| Predicate Device: | InBios International, Inc. Active Anthrax Detect Plus Rapid Test |
| (DEN220044) |
4
Device Description Summary
The SensiTox B. anthracis Toxin Test, run on the MultiPath Analyzer, detects lethal factor in venous whole blood samples using an immunofluorescence assay and the proprietary MultiPath detection technology.
A whole blood specimen, collected in dipotassium EDTA, from individuals with signs and symptoms consistent with inhalation anthrax and a likelihood of exposure, is used for the test. The blood sample is added directly to the SensiTox B. anthracis Cartridge, a single use consumable that contains all the reagents required to run the test. The Cartridge is loaded onto the MultiPath Analyzer for processing through the steps of the assay.
Once loaded onto the Analyzer, the barcodes on the cartridge that identify the test type and associated test specific information (manufacturer installed barcode) and sample (laboratory affixed barcode) are read. The cartridge is moved to the fluidics station where it is first heated to 35°C. The sample is then split into 3 equal aliquots in 3 distribution wells within the cartridge. The sample aliquots flow from the distribution wells to the reagent wells containing target-specific antibody conjugated fluorescent and magnetic particles in the form of lyophilized beads. Upon contact with the sample, the lyophilized beads rehydrate and the reaction mixtures flow into the imaging wells, the bottoms of which are coated with a dye cushion reagent. Upon contact with the reagents, the dye-cushion dissolves forming a dense opaque aqueous layer that separates the sample and reagents from the bottom optical surface of the Imaging Well. In the upper assay layer, the toxins, if present, bind to the magnetic and fluorescent particles tethering them together. The cartridge is incubated for 12 minutes to allow the reaction to take place and then is moved to the magnetics station. At the magnetics station, the imaging well is placed over permanent magnets that draw the magnetic particles and any fluorescent particles that are tethered to them via the target molecules through the dye-cushion layer, depositing them on the bottom imaging surface. The captured fluorescent particles are imaged and quantified using nonmagnified digital imaging.
The Analyzer can be run in batch mode or by random access. Up to 20 cartridges can be loaded onto the Analyzer in parallel. The first result is reported in approximately 21 minutes of loading the cartridge onto the Analyzer with subsequent results being reported in 2.5-minute increments. The results are interpreted using the MultiPath applications software as valid or invalid, and if valid, the results are reported as Lethal Factor detected. Results are displayed on the instrument touch screen and can be printed.
Intended Use/Indications for Use
The SensiTox B. anthracis Toxin Test for use with the MultiPath Analyzer, is a qualitative immunofluorescence assay to aid in the diagnosis of inhalation anthrax. The test is intended for the rapid, qualitative detection of lethal factor, a biomarker associated with Bacillus anthracis (B. anthracis). The test can be used with whole blood collected with dipotassium EDTA anticoagulant by venipuncture. This test is indicated for testing samples from individuals who have signs and symptoms consistent with inhalation anthrax and a likelihood of exposure to B. anthracis. A positive SensiTox B. anthracis Toxin Test result is presumptively diagnostic for B. anthracis
5
infection. Diagnosis of B. anthracis infection must be made in conjunction with medical history, likelihood of exposure, signs, and symptoms of disease, as well as other laboratory evidence. The definitive identification of B. anthracis from blood samples requires additional testing and confirmation procedures in consultation with public health or other authorities for whom reports are required. Testing should be performed and reported in accordance with current guidelines provided by the appropriate public health authorities. The level of lethal factor present in blood from individuals with early systemic infection is unknown. Negative results do not preclude infection with the biothreat microbial agents targeted by the device and should not be used as the sole basis for diagnosis, treatment, or other patient management decisions.
Laboratories performing the SensiTox B. anthracis Toxin Test must have the appropriate biosafety equipment, personal protective equipment (PPE), containment facilities, and personnel trained in the safe handling of clinical specimens potentially containing B. anthracis.
The SensiTox B. anthracis Toxin Test is for prescription use only.
This assay is not FDA-cleared or approved for testing blood or plasma donors.
Special Conditions for Use Statement(s)
For Prescription Use Only. Please refer to the SensiTox B. anthracis Toxin Test labeling for a more complete list of warnings, precautions, and contraindications.
Special Instrument Requirements
For use with the Multipath Analyzer
Indications for Use/Technology Comparison
| Description | First Light Diagnostics, Inc.
Subject Device
SensiTox B. anthracis Toxin Test | InBios International, Inc.
Predicate Device
DEN220044
Active Anthrax Detect Plus Rapid Test |
|--------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Regulation | 866.3046 | Same |
| Product Code | QUU | Same |
| Device Class | Class II | Same |
| Panel | Microbiology | Same |
| Intended Use | The SensiTox B. anthracis Toxin Test
for use with the MultiPath Analyzer, is
a qualitative immunofluorescence
assay to aid in the diagnosis of
inhalation anthrax. The test is
intended for the rapid, qualitative
detection of lethal factor, a biomarker
associated with Bacillus anthracis (B.
anthracis). The test can be used with
whole blood collected with | The Active Anthrax Detect Plus Rapid
Test point-of-care diagnostic test for
pulmonary anthrax is an in vitro
immunochromatographic device for use
as an aid in the diagnosis of inhalation
anthrax. It provides visual and rapid
qualitative detection of lethal factor of
Bacillus anthracis (B. anthracis). The test
can be used to test serum and venous
whole blood (dipotassium EDTA, sodium |
6
dipotassium EDTA anticoagulant by venipuncture. This test is indicated for testing samples from individuals who have signs and symptoms consistent inhalation anthrax and with a likelihood of exposure to B. anthracis. A positive SensiTox B. anthracis Toxin Test result is presumptively diagnostic for B. anthracis infection. Diagnosis of B. anthracis infection must be made in conjunction with medical history, likelihood of exposure, signs, and symptoms of disease, as well as other laboratory evidence. The definitive identification of B. anthracis from blood samples requires additional testing and confirmation procedures in consultation with public health or other authorities for whom reports are required. Testing should be performed and reported in accordance with current guidelines provided by the appropriate public health authorities. The level of lethal factor present in blood from individuals with early systemic infection is unknown. Negative results do not preclude infection with biothreat microbial agents the targeted by the device and should not be used as the sole basis for diagnosis, or other treatment, patient management decisions.
Laboratories performing the SensiTox B. anthracis Toxin Test must have the appropriate biosafety equipment, personal protective equipment (PPE), containment facilities, and personnel trained in the safe handling of clinical specimens potentially containing B. anthracis.
The SensiTox B. anthracis Toxin Test is for prescription use only.
citrate, and sodium heparin). The assay is indicated for testing samples from individuals who have signs and symptoms consistent with inhalation anthrax and a likelihood of exposure. This test is intended for use by military personnel, medical, and/or healthcare professionals only. The diagnosis of B. anthracis infection must be based on history, signs, symptoms, exposure likelihood, and additional laboratory evidence. A positive Active Anthrax Detect Plus Rapid Test result is presumptively diagnostic for B. anthracis infection. The definitive identification of B. anthracis from blood samples requires additional testing and confirmation procedures in consultation with public health or other authorities for whom reports are required. Testing should be performed and reported in accordance with current guidelines provided by the appropriate public health authorities. The level of lethal factor present in blood from individuals with early systemic infection is unknown. Negative results do not preclude infection with the biothreat microbial agents targeted by the device and should not be used as the sole basis for diagnosis, treatment, or other patient management decisions. This assay is for prescription use.
The distribution of in vitro diagnostic devices for Bacillus spp. detection must performed in accordance with be guidelines established by the public authorities health that address appropriate biosafety conditions, interpretation of test results, and coordination of findings with public health authorities.
This assay is not FDA-cleared or approved for testing blood or plasma donors.
7
| This assay is not FDA-cleared or
approved for testing blood or plasma
| donors. | ||
|---|---|---|
| Similarities | ||
| Sample Type | Whole blood collected with dipotassium EDTA anticoagulant by venipuncture | Serum and venous whole blood (dipotassium EDTA, sodium citrated, and sodium heparin) |
| Analyte | Lethal Factor | Same |
| Prescription Status | Prescription Use Only | Same |
| Antibodies | Anti-Lethal Factor antibodies | Same |
| Differences | ||
| Technology | Immunofluorescent assay | Immunoassay |
| Test Format | Fluidic cartridge with direct digital Imaging and automated interpretation | Lateral flow with visual interpretation |
| Automated | Yes | No |
| Instrument | Multipath Analyzer | None |
Non-Clinical and/or Clinical Tests Summary
Limit of Detection (LoD)
The limit of detection (LoD) for Lethal Factor was determined by adding recombinant Lethal Factor or native Lethal Factor contained in culture supernatants from the Ames and SK-102 strains of B. anthracis to K₂EDTA venous whole blood collected from healthy donors. A minimum of 5 serial dilutions of known concentrations of Lethal Factor were tested in replicates of 20 at concentrations ranging from 20 to 60 pg/mL.
The data were evaluated by analysis of hit rate (detected results/total number of test) as well as Probit analysis. The LoD was determined by combining the replicate data across the three cartridge lots and identifying the lowest LF concentration (pg/mL) with a ≥95% "Detected" hit rate. The LoD established for Lethal Factor is 50 pg/mL.
Reproducibility
The reproducibility of the SensiTox B. anthracis Toxin Test was evaluated at 3 sites over the course of 5 non-consecutive days by 2 operators per site each day. Three lots of cartridges were tested in this study. Randomized and blinded samples comprised of whole blood spiked with two concentrations of recombinant Lethal Factor – low positive (1.5X LoD), moderate positive (3X LoD), and negative (unspiked) were prepared and provided to each participating site. Each operator mixed a blinded sample with whole blood prescreened and known to be negative for Lethal Factor and tested in triplicate using the SensiTox B. anthracis Toxin Test.
As shown in Table 5.2, the overall reproducibility of the SensiTox B. anthracis Toxin Test is 98.9%. Of the 270 samples tested, there were 3 incorrect results reported from 3 samples (Table 5.3). Two low positive samples and 1 moderate positive sample generated negative results.
8
| Sample | Site 1 | Site 2 | Site 3 | Total | ||||
|---|---|---|---|---|---|---|---|---|
| Description | # | % Accuracy | # | % Accuracy | # | % Accuracy | # | % Accuracy |
| Negative | 30/30 | 100 | 30/30 | 100 | 30/30 | 100 | 90/90 | 100 |
| 75 pg/mL LF | 30/30 | 100 | 29/30 | 96.7 | 29/30 | 96.7 | 88/90 | 97.8 |
| 150 pg/mL LF | 30/30 | 100 | 29/30 | 96.7 | 30/30 | 100 | 89/90 | 98.9 |
| Total | 90/90 | 100 | 88/90 | 97.8 | 89/90 | 98.9 | 267/270 | 98.9 |
Table 5.2. Reproducibility study data analyzed by sample type and by site.
Table 5.3. Summary of reproducibility study analyzed by positive and negative samples.
| Site | Total
Samples | #
Invalid | FP | FN | TP | TN | % Accuracy
Positives | % Accuracy
Negatives |
|--------|------------------|--------------|----|----|-----|----|-------------------------|-------------------------|
| Site 1 | 90 | 4 | 0 | 0 | 60 | 30 | 100 | 100 |
| Site 2 | 90 | 2 | 0 | 2 | 58 | 30 | 96.7 | 100 |
| Site 3 | 90 | 0 | 0 | 1 | 59 | 30 | 98.3 | 100 |
| Total | 270 | 6 | 0 | 3 | 177 | 90 | 98.3 | 100 |
Analytical Reactivity (Inclusivity)
To evaluate the inclusivity of the SensiTox B. anthracis Toxin Test, 29 B. anthracis strains containing the wildtype pXO1 plasmid and representing geographical diversity of clinically relevant strains were tested (Table 5.4). Supernatants from mid-log phase cultures were isolated, sterilized, and the LF content quantified by ELISA. Based on this quantitation, supernatants from each strain were spiked into venous K₂EDTA anticoagulated whole blood at 3X LoD (150 pg/mL) and tested in triplicate. All 29 B. anthracis strains were detected.
9
| B. anthracis Strains | |
|---|---|
| Vollum 1B | Turkey 32 |
| CDC 684 | Zimbabwe 89 |
| CDC 607 | N-99 |
| K2129 | 108 |
| K3 | 506/ Heroin Ba |
| 2002013094 | SK-31 |
| RA3 | K1811 (Scotland) |
| Vollum | English Vollum |
| Ohio ACB | South African |
| G-28/BA1035 | K1285 |
| SK-128 | K4834 |
| PAK-1 | New Hampshire |
| Buffalo | Bekasi |
| Carbosap | Sterne |
| 205 |
Table 5.4. Clinically relevant strains of B. anthracis tested and detected.
Additionally, an in silico analysis of Lethal Factor amino sequences found in the National Center for Biotechnology Information (NCBI) database was conducted. Of the 303 unique B. anthracis strains identified, 299 (98.7%) had amino acid sequences identical to the strains tested in the inclusivity study, and 4 (1.3%) had amino acid substitutions not represented in the panel.
Analytical Specificity – Cross Reactivity
Analytical specificity testing was conducted to assess the potential cross reactivity of the SensiTox B. anthracis Toxin Test to bacterial, viral, protozoan, and fungal pathogens potentially found in human blood. Bacterial, protozoan, and fungal pathogens were typically tested at 1x106 CFU/mL and viral pathogens at 1x105 PFU/mL by the addition to pre-screened K2EDTA human venous whole blood. Each pathogen was tested in triplicate. A list of all pathogens and the concentrations tested is shown in Table 5.5.
With the exception of two B. cereus strains, G9241 and 03BB102, which contain the extrachromosomal plasmid pXO1 that harbors the gene for Lethal Factor, no pathogens crossreacted when tested in the SensiTox B. anthracis Toxin Test. These two cross-reactive strains of B. cereus were detected as expected.
10
Table 5.5. Bacteria, viruses, fungi, and protozoa tested for cross-reactivity. The entries marked with (*) indicate that those organisms were tested in % parasitemia. Entries marked with (**) indicate that those organisms were tested in IU/mL. The entries marked with (†) indicate that those organisms were tested in copies/mL
| Bacteria Tested with No Cross-Reactivity | |||
|---|---|---|---|
| Strain | CFU/mL | Strain | CFU/mL |
| Acinetobacter baumannii, 307-0294 | 1.0E+06 | Enterococcus faecium, ZeptoMetrix Z265 | 1.0E+06 |
| Bacillus cereus, ZeptoMetrix Z091 | 1.0E+06 | Escherichia coli, ZeptoMetrix 0801517 | 1.0E+06 |
| Bacillus cereus, 3A (Fri-41) | 1.0E+06 | Francisella philomiragia, O#319-036 | 1.0E+06 |
| Bacillus cereus, D17 | 1.0E+06 | Francisella tularensis, Schu S4 | 7.7E+05 |
| Bacillus cereus, E33L | 7.0E+05 | Haemophilus influenzae, type b; Eagan | 1.0E+06 |
| Bacillus cereus, m1550 | 1.0E+06 | Klebsiella aerogenes, ZeptoMetrix Z052 | 1.0E+06 |
| Bacillus cereus, MSX-A1 | 1.0E+06 | Klebsiella oxytoca, ZeptoMetrix Z115 | 1.0E+06 |
| Bacillus cereus, VD148 | 6.7E+05 | Klebsiella pneumoniae, KPC-2 | 1.0E+06 |
| Bacillus cereus, 03BB108 | 1.0E+06 | Legionella pneumophila, Philadelphia | 1.0E+06 |
| Bacillus circulans Jordan, 26 | 1.0E+06 | Leishmania donovanii, MHOM/IN/80/DD8 | 1.0E+06 |
| Bacillus coagulans Hammer, NRS 609 | 1.0E+06 | Listeria monocytogenes, Serotype 1/2b | 1.0E+06 |
| Bacillus mycoides Flugge, NRS 273 | 1.0E+06 | Mycobacterium tuberculosis (avirulant), H37Ra-1 | 1.0E+06 |
| Bacillus subtilis Marburg | 1.0E+06 | Mycoplasma pneumoniae, M129 | 1.0E+06 |
| Bacillus thuringiensis, Al Hakam | 1.0E+06 | Neisseria gonorrhoeae, ZeptoMetrix Z017 | 1.0E+06 |
| Bacillus thuringiensis, Berliner, CCUG 7429T | 1.0E+06 | Neisseria meningitidis, Serogroup A | 1.0E+06 |
| Bacillus thuringiensis, NRRL B-3792 | 1.0E+06 | Proteus mirabilis, ZeptoMetrix Z050 | 1.0E+06 |
| Bacillus thuringiensis, USDA HD522 | 4.0E+05 | Pseudomonas aeruginosa, ZeptoMetrix Z139 | 1.0E+06 |
| Bacillus thuringiensis, HD1011 | 1.0E+06 | Pseudomonas luteola, JCM 3352 | 1.0E+06 |
| Bacillus thuringiensis, HD974 | 1.0E+06 | Rickettsia prowzekii, Naples-1 | 1.0E+05 |
| Bacillus thuringiensis, HD571 | 1.0E+06 | Rickettsia sibirica, 246 | 1.0E+05 |
| Bacillus thuringiensis, HD682 | 1.0E+06 | Salmonella enterica, Typhi, ZeptoMetrix Z152 | 1.0E+06 |
| Bacillus thuringiensis, ZeptoMetrix Z096 | 1.0E+06 | Salmonella enterica, Typhimurium, ZeptoMetrix Z005 | 1.0E+06 |
| Bacillus thuringiensis, 97-27 | 1.0E+06 | Serratia marcescens, ZeptoMetrix Z053 | 1.0E+06 |
| Bacteroides fragilis, ZeptoMetrix Z029 | 1.0E+06 | Shigella sonnei, ZeptoMetrix Z004 | 1.0E+06 |
| Bordetella bronchiseptica, ZeptoMetrix | 1.0E+06 | Staphylococcus aureus, MSSA; ΔmecA | 1.0E+06 |
| Borrelia burgdorferi, B31 | 1.0E+06 | Staphylococcus epidermidis, MSSE; HER 1292 | 1.0E+06 |
| Brucella melitensis, 16M (NCTC 10094) | 1.0E+06 | Streptococcus agalactiae, ZeptoMetrix Z019 | 1.0E+06 |
| Burkholderia cepacia, ZeptoMetrix Z066 | 1.0E+06 | Streptococcus pneumoniae, ZeptoMetrix Z022 | 1.0E+06 |
| Burkholderia mallei, Ivan (NTCC 10230) | 1.0E+06 | Streptococcus pyogenes, ZeptoMetrix Z018 | 1.0E+06 |
| Burkholderia pseudomallei, NCTC 4845 | 1.0E+06 | Vibrio cholera, ZeptoMetrix Z133 | 1.0E+06 |
| Chlamydophila pneumoniae, ZeptoMetrix Z500 | 1.0E+06 | Yersinia aldovae, CNCTC Y 49/84 | 1.0E+06 |
| Citrobacter koseri, ZeptoMetrix Z039 | 1.0E+06 | Yersinia bercovieri, CDC 2475-87 | 1.0E+06 |
| Clostridium bifermentans, ZeptoMetrix Z176 | 1.0E+06 | Yersinia enterocolitica, ZeptoMetrix Z036 | 1.0E+06 |
| Clostridium botulinum, IBCA 10-7060 | 7.6E+04 | Yersinia fredericksenii, CDC 1462-81 | 1.0E+06 |
| Clostridium perfringens, Type A | 1.0E+06 | Yersinia intermedia, CDC 881-81 | 1.0E+06 |
| Clostridium sordellii, ZeptoMetrix Z077 | 1.0E+06 | Yersinia kristensenii, CDC 1460-81 | 1.0E+06 |
| Clostridium sporogenes, ZeptoMetrix Z355 | 1.0E+06 | Yersinia mollaretti, CDC 2465-87 | 1.0E+06 |
| Corynebacterium diptheriae, ZeptoMetrix Z116 | 1.0E+06 | Yersinia pestis, A1122 | 1.0E+06 |
| Enterococcus faecalis, ZeptoMetrix Z346 | 1.0E+06 | Yersinia pseudotuberculosis, ZeptoMetrix Z222 | 1.0E+06 |
| Yersinia ruckeri, CDC 2396-61 | 1.0E+06 |
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| Bacteria Tested with Cross-Reactivity | |||
|---|---|---|---|
| Strain | CFU/mL | Strain | CFU/mL |
| Bacillus cereus, G9242 | 1.0E+06 | Bacillus cereus, 03BB102 | 1.0E+06 |
| Viruses Tested with No Cross-Reactivity | |||
| Strain | PFU/mL | Strain | PFU/mL |
| Adenovirus (C1), 1 (Species C)** | 1.0E+05 | Influenza A (H1N1), New York/18/09 | 2.9E+04 |
| Chikungunya Virus, S-27 | 1.0E+05 | Influenza A (H3N2), Kumamoto/102/02 | 1.2E+04 |
| Coronavirus 229E, 229E | 9.1E+04 | Influenza B, B/Colorado/06/2017** | 1.0E+05 |
| Cytomegalovirus, AD169 | 1.0E+05 | Japanese Encephalitis Virus (JEV), Nakayama | 1.0E+05 |
| Eastern Equine Encephalitis Virus, FL93-939 | 1.0E+05 | Measles Virus, ZeptoMetrix 0810025CF | 2.9E+04 |
| Enterovirus Type 68, 2014 isolate 1 | 1.0E+05 | Mumps Virus, 1 | 1.7E+04 |
| Epstein-Barr Virus (EBV), B95-8 | 1.0E+05 | Parainfluenza Virus 1, ZeptoMetrix 0810014CF | 8.8E+04 |
| Hantaan Virus, 76-118 | 2.0E+04 | Respiratory Syncytial Virus Type A, 1/2015 | |
| isolate 1 | 8.8E+04 | ||
| Hepatitis A Virus (HAV), HM 175 (clone 1)** | 1.0E+05 | Rhinovirus, 16** | 1.0E+05 |
| Hepatitis B Virus (HBV), ZeptoMetrix | |||
| 0810031C** | 1.0E+05 | Rubella Virus, ZeptoMetrix 0810048CF | 2.5E+04 |
| Hepatitis C Virus (HCV), Seracare** | 1.0E+05 | St. Louis Encephalitis Virus, V 07457 | 1.0E+05 |
| Herpes Simplex Virus 1 (HSV-1), MacIntyre | 1.0E+05 | Vaccinia Virus, ZeptoMetrix 0810310CF | 1.0E+05 |
| Herpes Simplex Virus 2 (HSV-2), G Strain** | 1.0E+05 | Varicella Zoster Virus (VZV), A | 1.0E+05 |
| Human Herpesvirus 6A (HHV-6A), GS+ | 1.0E+05 | West Nile Virus, CO 08-13386 | 1.0E+05 |
| Human Immunodeficiency Virus (HIV), BaL** | 1.0E+05 | Western Equine Encephalitis, CO921356 | 1.0E+05 |
| Human Metapneumovirus, IA 10-2003 | 8.8E+04 | Yellow Fever Virus, 17D | 1.7E+04 |
| Fungi and Protozoa Tested with no Cross-Reactivity | |||
| Strain | CFU/mL | Strain | CFU/mL |
| Aspergillus fumigatus, ZeptoMetrix Z014 | 1.0E+06 | Cryptococcus neoformans, serotype A | 1.0E+06 |
| Candida albicans, ZeptoMetrix Z006 | 1.0E+06 | Trypanosoma brucei, Lister 427 VSG 221 | 1.0E+06 |
| Strain | CFU/mL | Strain | CFU/mL |
| Acinetobacter baumannii, 307-0294 | 1.0E+06 | Enterococcus faecalis, ZeptoMetrix Z346 | 1.0E+06 |
| Bacillus cereus, ZeptoMetrix Z091 | 1.0E+06 | Enterococcus faecium, ZeptoMetrix Z265 | 1.0E+06 |
| Bacillus cereus, 3A (Fri-41) | 1.0E+06 | Escherichia coli, ZeptoMetrix 0801517 | 1.0E+06 |
| Bacillus cereus, D17 | 1.0E+06 | Francisella philomiragia, O#319-036 | 1.0E+06 |
| Bacillus cereus, E33L | 1.0E+06 | Haemophilus influenzae, type b, Eagan | 1.0E+06 |
| Bacillus cereus, m1550 | 1.0E+06 | Klebsiella aerogenes, ZeptoMetrix Z052 | 1.0E+06 |
| Bacillus cereus, MSX-A1 | 1.0E+06 | Klebsiella oxytoca, ZeptoMetrix Z115 | 1.0E+06 |
| Bacillus cereus, VD148 | 7.0E+05 | Klebsiella pneumoniae, KPC-2 | 1.0E+06 |
| Bacillus cereus, 03BB108 | 1.0E+06 | Legionella pneumophila, Philadelphia | 1.0E+06 |
| Bacillus cereus, G9241 | 1.0E+06 | Listeria monocytogenes, Serotype 1/2b | 1.0E+06 |
| Bacillus cereus, 03BB102 | 6.7E+05 | Mycobacterium tuberculosis (avirulant), | |
| H37Ra-1 | 1.0E+06 | ||
| Bacillus circulans Jordan, 26 | 1.0E+06 | Mycoplasma pneumoniae, M129 | 1.0E+06 |
| Bacillus coagulans Hammer, NRS 609 | 1.0E+06 | Neisseria gonorrhoeae, ZeptoMetrix Z017 | 1.0E+06 |
| Bacillus mycoides Flugge, NRS 273 | 1.0E+06 | Neisseria meningitidis, Serogroup A | 1.0E+06 |
| Bacillus subtilis, Marburg | 1.0E+06 | Proteus mirabilis, ZeptoMetrix Z050 | 1.0E+06 |
| Bacillus thuringiensis, Al Hakam | 1.0E+06 | Pseudomonas aeruginosa, ZeptoMetrix | |
| Z139 | 1.0E+06 | ||
| Bacillus thuringiensis, Berliner, CCUG 7429T | 1.0E+06 | Pseudomonas luteola, JCM 3352 | 1.0E+06 |
| Bacillus thuringiensis, NRRL B-3792 | 1.0E+06 | Salmonella enterica, Typhi, ZeptoMetrix | |
| Z152 | 1.0E+06 | ||
| Bacillus thuringiensis, USDA HD522 | 1.0E+06 | Salmonella enterica, Typhimurium, | |
| ZeptoMetrix Z005 | 1.0E+06 | ||
| Bacillus thuringiensis, HD1011 | 1.0E+06 | Serratia marcescens, ZeptoMetrix Z053 | 1.0E+06 |
| Bacillus thuringiensis, HD974 | 4.0E+05 | Shigella sonnei, ZeptoMetrix Z004 | 1.0E+06 |
| Bacillus thuringiensis, HD571 | 1.0E+06 | Staphylococcus aureus, MSSA; $\Delta$ mecA | 1.0E+06 |
| Bacillus thuringiensis, HD682 | 1.0E+06 | Staphylococcus epidermidis, MSSE; HER | |
| 1292 | 1.0E+06 | ||
| Bacillus thuringiensis, ZeptoMetrix Z096 | 1.0E+06 | Streptococcus agalactiae, ZeptoMetrix Z019 | 1.0E+06 |
| Bacillus thuringiensis, 97-27 | 1.0E+06 | Streptococcus pneumoniae, ZeptoMetrix | |
| Z022 | 1.0E+06 | ||
| Bacteroides fragilis, ZeptoMetrix Z029 | 1.0E+06 | Streptococcus pyogenes, ZeptoMetrix Z018 | 1.0E+06 |
| Bordetella bronchiseptica, ZeptoMetrix | 1.0E+06 | Vibrio cholera, ZeptoMetrix Z133 | 1.0E+06 |
| Borrelia burgdorferi, B31 | 1.0E+06 | Yersinia aldovae, CNCTC Y 49/84 | 1.0E+06 |
| Burkholderia cepacia, ZeptoMetrix Z066 | 1.0E+06 | Yersinia bercovieri, CDC 2475-87 | 1.0E+06 |
| Chlamydophila pneumoniae, ZeptoMetrix Z500 | 1.0E+06 | Yersinia enterocolitica, ZeptoMetrix Z036 | 1.0E+06 |
| Citrobacter koseri, ZeptoMetrix Z039 | 1.0E+06 | Yersinia fredericksenii, CDC 1462-81 | 1.0E+06 |
| Clostridium bifermentans, Z176 | 1.0E+06 | Yersinia intermedia, CDC 881-81 | 1.0E+06 |
| Clostridium perfringens, Type A | 1.0E+06 | Yersinia kristensenii, CDC 1460-81 | 1.0E+06 |
| Clostridium sordellii, ZeptoMetrix Z077 | 1.0E+06 | Yersinia mollaretti, CDC 2465-87 | 1.0E+06 |
| Bacteria | |||
| Strain | CFU/mL | Strain | CFU/mL |
| Clostridium sporogenes, ZeptoMetrix Z355 | 1.0E+06 | Yersinia pseudotuberculosis, ZeptoMetrix Z222 | 1.0E+06 |
| Corynebacterium diptheriae, ZeptoMetrix Z116 | 1.0E+06 | Yersinia ruckeri, CDC 2396-61 | 1.0E+06 |
| Viruses | |||
| Strain | PFU/mL | Strain | PFU/mL |
| Adenovirus (C1), 1 (Species C)* | 1.0E+05 | Influenza A (H1N1), New York/18/09 | 2.9E+04 |
| Coronavirus 229E, 229E | 9.1E+04 | Influenza A (H3N2), Kumamoto/102/02 | 1.2E+04 |
| Cytomegalovirus (CMV), AD169 | 1.0E+05 | Influenza B, B/Colorado/06/2017* | 1.0E+05 |
| Enterovirus Type 68, 2014 isolate 1 | 1.0E+05 | Measles Virus, ZeptoMetrix 0810025CF | 2.9E+04 |
| Epstein-Barr Virus (EBV), B95-8 | 1.0E+05 | Mumps Virus, 1 | 1.7E+04 |
| Hepatitis A Virus (HAV), HM 175 (clone 1)* | 1.0E+05 | Parainfluenza Virus 1, ZeptoMetrix 0810014CF | 8.8E+04 |
| Hepatitis B Virus (HBV), ZeptoMetrix 0810031C* | 1.0E+05 | Respiratory Syncytial Virus Type A, 1/2015 isolate 1 | 8.8E+04 |
| Hepatitis C Virus (HCV), Seracare* | 1.0E+05 | Rhinovirus, 16* | 1.0E+05 |
| Herpes Simplex Virus 1 (HSV-1), MacIntyre | 1.0E+05 | Rubella Virus, ZeptoMetrix 0810048CF | 2.5E+04 |
| Herpes Simplex Virus 2 (HSV-2), G Strain* | 1.0E+05 | Vaccinia Virus, ZeptoMetrix 0810310CF | 1.0E+05 |
| Human Herpesvirus 6A (HHV-6A), GS* | 1.0E+05 | Varicella Zoster Virus (VZV), A | 1.0E+05 |
| Human Immunodeficiency Virus (HIV), BaL* | 1.0E+05 | Yellow Fever Virus, 17D | 1.7E+04 |
| Human Metapneumovirus, IA 10-2003 | 8.8E+04 | ||
| Fungi and Protozoa | |||
| Strain | CFU/mL | Strain | CFU/mL |
| Aspergillus fumigatus., ZeptoMetrix Z014 | 1.0E+06 | Cryptococcus neoformans, serotype A | 1.0E+06 |
Analytical Specificity – Microbial Interference
Babesia microti, R1*
Testing was conducted to assess the interference of bacterial, viral, fungal, and protozoan pathogens potentially found in human blood on the detection of B. anthracis Lethal Factor with the SensiTox B. anthracis Toxin Test. Bacterial, fungal, and protozoan pathogens were typically tested at 1x106 CFU/mL and viral pathogens at 1x105 PFU/mL by addition to pre-screened K₂EDTA human venous whole blood containing 150 pg/mL of recombinant Lethal Factor (3X LoD). Each pathogen was tested in triplicate.
3.9 %
None of the organisms shown in Table 5.6 interfered with the SensiTox B. anthracis Toxin Test at the concentrations shown and generated detected results for all replicates containing 150 pg/mL of Lethal Factor.
12
Table 5.6. Bacteria, viruses, fungi, and protozoa tested for interference. Entries marked with (*) indicate that those organisms were tested in IU/mL. The entries marked with (†) indicate that those organisms were tested in copies/mL.
13
Interfering Substances
Candida albicans, ZeptoMetrix Z006
Endogenous and exogenous substances commonly found in blood were evaluated for their potential effect on the performance of the SensiTox B. anthracis Toxin Test. Drugs and their metabolites were tested at approximately 3 times the highest concentration reported following therapeutic dosage. Endogenous substances were tested at the highest physiological concentration expected in the population. The solvents used to dissolve exogenous substances used in the study were tested independently.
Trypanosoma brucei, Lister 427 VSG 221
1.0E+06
Each compound was tested in K₂EDTA anticoagulated whole blood unspiked and spiked with 150 pg/mL (3X LoD) of recombinant Lethal Factor and run in triplicate. The list of endogenous and exogenous substances evaluated and the concentrations at which they were tested is shown in Table 5.7. None of the substances tested interfered with the SensiTox B. anthracis Toxin Test.
1.0E+06
14
| Endogenous Substances | Concentration | ||
|---|---|---|---|
| Glucose | 10 mg/mL | ||
| Hemoglobin | 2 mg/mL | ||
| Human Immunoglobulins (IgG) | 19.7 mg/mL | ||
| Triglycerides | 22 mg/mL | ||
| Cholesterol | 2.5 mg/mL | ||
| Human Serum Albumin | 50 mg/mL | ||
| Bilirubin | 200 µg/mL | ||
| Human Anti-Mouse Antibodies | 1 µg/mL | ||
| Exogenous Substances | Concentration | Exogenous Substances | Concentration |
| Acetaminophen | 200 µg/mL | Heparin | 90.3 U/mL |
| Acid-citrate-dextrose 3x | 300 µL/mL | Ibuprofen | 500 µg/mL |
| Albuterol (Salbutamol) | 400 ng/mL | Malarone (Atovaquone) | 180 µg/mL |
| Amoxicillin | 75.2 µg/mL | Mefloquine | 18 µg/mL |
| Artemisinin | 9 µg/mL | N-acetylcysteine | 1.7 mg/mL |
| Ascorbic acid | 60 µg/mL | Naproxen sodium | 500 µg/mL |
| Aspirin | 652 µg/mL | Oseltamivir (Tamiflu) | 4.95 µg/mL |
| Biothrax | 0.9 µL/mL | Ribavirin | 51.3 µg/mL |
| Cefotaxime | 306 µg/mL | Rifampin | 66 µg/mL |
| Chloroquine | 36 µg/mL | Sodium citrate | 9.6 mg/mL |
| Ciprofloxacin | 10 µg/mL | Sodium polyanetholesulfonate | 1.5 mg/mL |
| Cromolyn sodium | 825 ng/mL | Streptomycin | 450 µg/mL |
| Doxycycline | 30 µg/mL | Sulfamethoxazole | 400 µg/mL |
| EDTA | 5.4 mg/mL | Tetracycline | 15 µg/mL |
| Erythromycin | 60 µg/mL | Tobramycin | 24 µg/mL |
| Flunisolide (Flovent) | 90 ng/mL | Trimethoprim | 40 µg/mL |
| Gentamicin sulfate | 10 µg/mL |
Table 5.7 Endogenous and exogenous interferents tested.
Hook Effect
This study was conducted to determine if a false negative result could be produced by high concentrations of analyte. Recombinant LF was diluted to concentrations ranging from 50 pg/mL to 50 µg/mL in K₂EDTA anticoagulated venous whole blood and three replicates of each dilution were tested.
Table 5.8 summarizes the qualitative results obtained in the study. All concentrations of LF greater than 50 pg/mL yielded 3/3 detected results. At 50 pg/mL, 1/3 replicates yielded a result of not detected. This result was not unexpected as 50 pg/mL is the limit of detection (LoD) of the SensiTox B. anthracis Toxin Test. No hook effect was observed in the reporting of the qualitative data between 50 pg/mL to 50 µg/mL of LF in K₂EDTA anticoagulated venous whole blood.
15
| Dilution Name | Lethal Factor (pg/mL) | # Detected / # Tested | # Invalid |
|---|---|---|---|
| S1 | 50,000,000 | 3 / 3 | 0 |
| S2 | 10,000,000 | 3 / 3 | 0 |
| S3 | 2,000,000 | 3 / 3 | 0 |
| S4 | 400,000 | 3 / 3 | 0 |
| S5 | 80,000 | 3 / 3 | 0 |
| S6 | 16,000 | 3 / 3 | 1 |
| S7 | 3,200 | 3 / 3 | 0 |
| S8 | 640 | 3 / 3 | 0 |
| S9 | 128 | 3 / 3 | 0 |
| S10 | 50 | 2 / 3 | 0 |
| Table 5.8. Qualitative results with LF concentrations ranging from 50 pg/mL – 50 µg/mL | ||
|---|---|---|
Clinical Performance Evaluation
The performance of the SensiTox B. anthracis Toxin Test was evaluated at three sites across the US. The evaluation consisted of two study arms, one with residual whole blood specimens collected in K₂EDTA for routine hematology analysis to determine negative percent agreement (NPA), and one with prospectively collected whole blood specimens from consented febrile patients that were spiked with recombinant or native Lethal Factor to determine positive percent agreement (PPA). All specimens were tested by the SensiTox B. anthracis Toxin Test within 72 hours of draw.
A total of 325 residual blood specimens were collected at a single clinical site. Seven specimens were withdrawn from this arm of the study, resulting in 318 specimens that were tested at two sites and included in the data analysis.
For the prospective study, a total of 126 subjects presenting with fever and flu-like symptoms were enrolled for the collection of fresh venous whole blood specimens. Twenty-one (21) specimens were withdrawn from the study resulting in 105 eligible samples.
For the prospective arm of the study, patient specimens were tested at a single site. Additionally, contrived specimens prepared from the prospectively collected blood specimens and containing either native Lethal Factor (LF) contained in cell supernatants at 75 pg/mL (1.5X LoD) and 250 pg/mL (5X LoD) or recombinant LF at concentrations of 75 pg/mL, and 5 μg/mL were prepared and tested blinded at a second site.
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Table 5.9 summarizes the data from the testing of residual specimens at two sites. All specimens tested reported not detected results for B. anthracis Lethal Factor for a 100% NPA.
| All Sites | Expected | |||
|---|---|---|---|---|
| Pos | Neg | Total | ||
| Residual whole blood specimens | ||||
| SensiTox B. anthracis | ||||
| Toxin Test | Pos (LF detected) | 0 | 0 | 0 |
| Neg (LF Not detected) | 0 | 318 | 318 | |
| Total | 0 | 318 | 318 | |
| All Sites | (95% C.I.) | |||
| Negative Percent Agreement (NPA) (%) | 100.0% (98.8% - 100.0%) |
| Table 5.9. Performance summary for residual whole blood specimens tested |
|---|
In the prospective study, two vials of blood drawn from 105 subjects presenting with fever and flu-like symptoms were tested at two sites. Table 5.10 shows the overall data summary with a performance of 96.2% PPA and 100% NPA. Four false negative results, generated at a concentration of 75 pg/mL LF (1.5X LoD), were reported in the contrived study.
| All Sites | Expected | |||
|---|---|---|---|---|
| Pos | Neg | Total | ||
| Specimens from the Prospective Arm | ||||
| SensiTox B. anthracis | ||||
| Toxin Test | Pos (LF detected) | 101 | 0 | 101 |
| Neg (LF not detected) | 4 | 105 | 109 | |
| Total | 105 | 105 | 210 | |
| All Sites | (95% C.I.) | |||
| Positive Percent Agreement (PPA) (%) | 96.2%* (90.6% - 98.5%) | |||
| Negative Percent Agreement (NPA) (%) | 100.0% (96.5% - 100.0%) |
- All samples were confirmed positive when retested.
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Conclusion
The conclusions drawn from the nonclinical and clinical tests demonstrate that the device is as safe, as effective, and performs as well as or better than the legally marketed device. 807.92(b)(3).