GAMMA PHAGE LYSIS ASSAY FOR THE IDENTIFICATION OF BACILLUS ANTHRAC
K143592 · The Surgeon General, Department of the Army · NVQ · Apr 16, 2015 · Microbiology
Device Facts
Record ID
K143592
Device Name
GAMMA PHAGE LYSIS ASSAY FOR THE IDENTIFICATION OF BACILLUS ANTHRAC
Applicant
The Surgeon General, Department of the Army
Product Code
NVQ · Microbiology
Decision Date
Apr 16, 2015
Decision
SESE
Submission Type
Special
Regulation
21 CFR 866.3045
Device Class
Class 2
Indications for Use
The Gamma Phage assay is a lytic phage assay specific for Bacillus anthracis. The Gamma Phage assay (common name) can be used on suspect non-hemolytic, aerobic, gram-positive, "ground-glass"- appearing colonies from sheep blood agar in conjunction with other markers and testing for the identification of Bacillus anthracis. The assay is not intended for screening of blood or plasma donors. Use of this assay is limited to designated laboratory Response Network (LRN) and Department of Defense (D0D).
Device Story
Lytic bacteriophage assay for identification of Bacillus anthracis; utilizes gamma phage that binds to specific cell-surface components of susceptible bacteria; phage DNA injection leads to replication and production of PlyG lysine; results in cell lysis and release of progeny phage; performed in LRN and DoD laboratories by trained personnel; input is suspect bacterial colonies from sheep blood agar; output is visual observation of lysis; used in conjunction with other markers (e.g., capsule demonstration) to confirm B. anthracis identification; aids clinical/public health decision-making regarding potential anthrax exposure.
Clinical Evidence
No clinical data provided. Bench testing only.
Technological Characteristics
Lytic bacteriophage suspension; positive control (B. anthracis Sterne strain); negative control (B. cereus). Requires 5% sheep blood agar, inoculating loops, and incubator (35+/- 2 °C). Biological safety cabinet required for handling. No software or electronic components.
Indications for Use
Indicated for the identification of Bacillus anthracis in suspect non-hemolytic, aerobic, gram-positive, "ground-glass"-appearing colonies from sheep blood agar. Restricted to designated Laboratory Response Network (LRN) and Department of Defense (DoD) laboratories. Not for blood or plasma donor screening.
Regulatory Classification
Identification
An in vitro diagnostic device for Bacillus species (spp.) detection is a prescription device used to detect and differentiate among Bacillus spp. and presumptively identify B. anthracis and other Bacillus spp. from cultured isolates or clinical specimens as an aid in the diagnosis of anthrax and other diseases caused by Bacillus spp. This device may consist of Bacillus spp. antisera conjugated with a fluorescent dye (immunofluorescent reagents) used to presumptively identify bacillus-like organisms in clinical specimens; bacteriophage used for differentiating B. anthracis from other Bacillus spp. based on susceptibility to lysis by the phage; or antigens used to identify antibodies to B. anthracis (anti-toxin and anti-capsular) in serum. Bacillus infections include anthrax (cutaneous, inhalational, or gastrointestinal) caused by B. anthracis, and gastrointestinal disease and non-gastrointestinal infections caused by B. cereus.
Special Controls
*Classification.* Class II (special controls). The special controls are set forth in FDA's special controls guideline document entitled “In Vitro Diagnostic Devices for*Bacillus* spp. Detection; Class II Special Controls Guideline for Industry and Food and Drug Administration Staff.” For availability of the guideline document, see § 866.1(e).(c)
*Restriction on Distribution.* The distribution of these devices is limited to laboratories that follow public health guidelines that address appropriate biosafety conditions, interpretation of test results, and coordination of findings with public health authorities.(d)
*Restriction on Use.* The use of this device is restricted to prescription use and must comply with the following:(1) The device must be in the possession of:
(i)(A) A person, or his agents or employees, regularly and lawfully engaged in the manufacture, transportation, storage, or wholesale or retail distribution of such device; or
(B) A practitioner, such as a physician, licensed by law to use or order the use of such device; and
(ii) The device must be sold only to or on the prescription or other order of such practitioner for use in the course of his professional practice.
(2) The label of the device shall bear the statement “Caution: Federal law restricts this device to sale by or on the order of a ____”, the blank to be filled with the word “physician” or with the descriptive designation of any other practitioner licensed by the law of the State in which he practices to use or order the use of the device.
(3) Any labeling, as defined in section 201(m) of the Federal Food, Drug, and Cosmetic Act, whether or not it is on or within a package from which the device is to be dispensed, distributed by, or on behalf of the manufacturer, packer, or distributor of the device, that furnishes or purports to furnish information for use of the device contains adequate information for such use, including indications, effects, routes, methods, and frequency and duration of administration and any relevant hazards, contraindications, side effects, and precautions, under which practitioners licensed by law to employ the device can use the device safely and for the purposes for which it is intended, including all purposes for which it is advertised or represented. This information will not be required on so-called reminder-piece labeling which calls attention to the name of the device but does not include indications or other use information.
(4) All labeling, except labels and cartons, bearing information for use of the device also bears the date of the issuance or the date of the latest revision of such labeling.
Predicate Devices
Gamma Phage Lysis for the Identification of Bacillus anthracis (K051794)
Submission Summary (Full Text)
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SPECIAL 510(k): Device Modification Decision Summary
To: THE FILE
RE: DOCUMENT NUMBER K143592
This 510(k) submission contains information/data on modifications made to the SUBMITTER'S own Class II, Class III or Class I devices requiring 510(k). The following items are present and acceptable:
1. The name and 510(k) number of the SUBMITTER'S previously cleared device.
GAMMA PHAGE LYSIS ASSAY FOR THE IDENTIFICATION OF BACILLUS ANTHRACIS 510(k) Number: K051794
2. Submitter's statement that the INDICATION/INTENDED USE of the modified device as described in its labeling HAS NOT CHANGED along with the proposed labeling which includes instructions for use, package labeling, and, if available, advertisements or promotional materials (labeling changes are permitted as long as they do not affect the intended use).
3. A description of the device MODIFICATION(S):
The modification presented in this special 510(k) consisted of changing the Bacillus anthracis positive control from the specified Pasteur strain, to the Sterne strain. The reason for the change was to allow laboratories to maintain a non-listed agent (Sterne strain), versus the Pasteur strain that is a biological select agent, and reduce logistics burdens imposed by the use of a select agent strain without compromising the assay performance. In addition, supporting data in the form of potency testing was provided demonstrating that while the Bacillus anthracis Sterne strain is less sensitive to gamma phage lysis than the Pasteur strain, it is more representative of the gamma phage reaction when compared with wild-type Bacillus anthracis (e.g., Ames strain) and is therefore a more appropriate positive control.
In addition to changing the Bacillus anthracis positive control strain from Pasteur to Sterne, the instructions for use has been updated to include some additional sources and forms (viable lyophilized cells and/or spore suspension) of both the positive (Bacillus anthracis) and negative control (Bacillus cereus) materials. As with the original 510k submission, the control materials are listed as "available controls". Prior to use these materials are used to prepare fresh cultures of both the positive or negative controls that are then used as quality control materials for the gamma phage lysis assay. Testing and validation information was provided for the control materials BC3366, BC3133 and BC3367 and Certificate of Analysis (COAs) were provided for the control materials ATCC14579 (from ATCC) and 19102 (from Colorado Serum Company).
The FUNDAMENTAL SCIENTIFIC TECHNOLOGY of the modified device has not changed.
4. Comparison Information:
Similarities to applicant's legally marketed predicate device include:
The procedure for running the Gamma Phage Lysis Assay for testing isolated colonies of gram positive bacilli with colony morphology typical of Bacillus anthracis outlined in the Gamma Phage Lysis Assay for the Identification of Bacillus anthracis Instructions for Use remains unchanged. In addition the procedure for running the positive and negative controls as part of the Quality Control testing remains unchanged and involves preparation of fresh cultures of the control strains by inoculation of a Sheep Blood Agar (SBA) plate – streak for isolation and incubate overnight.
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Table 1: Similarities between the predicate device (K051794) and the proposed device (K143592)
| Feature | K051794
Predicate Device | K143592
Proposed Device |
| --- | --- | --- |
| Bacillus anthracis
Gamma Phage
Suspension | Bacillus anthracis Gamma Phage Suspension 0.5 ml (BP3123) | Same |
| Specimen | Gamma Phage Assay should be performed on isolated colonies of gram positive bacilli with colony morphology typical of B. anthracis | Same |
| Materials required but not supplied | • 5% Sheep Blood Agar plate
• Inoculating loops, 1μl and 10 μl
• Aerosol resistant pipette tips
• Disinfectant | Same |
| Equipment required | • Pipettor, 5-50 μl
• Incubator, 35+/- 2 °C
• Biological Safety Cabinet, Class II
• Refrigerator, 2-8 °C | Same |
Differences to applicant's legally marketed predicate device include:
The Gamma Phage Lysis Assay for the Identification of Bacillus anthracis Instructions for Use has been updated to include Bacillus anthracis Sterne strain as the positive control. In addition the "materials" section has been updated to include some additional sources and forms (viable lyophilized cells and/or spore suspension) of both the positive and negative control materials (see Table 2).
Table 2: Differences between the predicate device (K051794) and the proposed device (K143592)
| Feature | K051794
Predicate Device | K143592
Proposed Device |
| --- | --- | --- |
| Positive Control | Bacillus anthracis Pasteur strain spore suspension 1.0 ml (BC3132) | Bacillus anthracis Sterne strain viable lyophilized cells (BC3366)
Colorado Serum Company (19102) Anthrax Spore Vaccine – 1.0 ml suspension of viable Bacillus anthracis Sterne strain 34F2 spores |
| Negative Control | Bacillus cereus spore suspension 1.0 ml (BC3133) | Bacillus cereus spore suspension 1.0 ml (BC3133) - same
Bacillus cereus lyophilized cells (BC3367)
ATCC 14579 – Bacillus cereus freeze-dried (lyophilized) |
| Reporting – Capsule Staining Techniques | A positive gamma phage result, in conjunction with a positive result for capsule, is considered confirmatory identification of B. anthracis. Capsule may be demonstrated by colony morphology on bicarbonate agar after incubation in enhanced CO2 or by staining techniques (India ink, M'Fadyean, or capsule DFA). | A positive gamma phage result, in conjunction with a positive result for capsule, is considered confirmatory identification of B. anthracis. Capsule may be demonstrated by colony morphology on bicarbonate agar after incubation in enhanced CO2 or by staining techniques (India ink or M'Fadyean).
Difference - Capsule DFA removed. |
Contact information for the additional sources (Colorado Serum Company and ATTC) was provided with the following disclaimer "Names of vendors or manufacturers are provided as examples of suitable product sources. Inclusion does not imply endorsement by the Centers for Disease Control and Prevention, the Department of Health and Human Services or the Federal Bureau of Investigation". The "interpretation of results" section has also been updated with a description and
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images of what to expect when using the *Bacillus anthracis* Sterne strain as the positive control. However, it does not change the interpretation of the quality controls or the wild type strains. The "reporting" section has been updated to (1) remove capsule DFA as it is no longer used as a staining technique for this assay and (2) to include the requirement that all test results (positive, negative, inconclusive) should be submitted to CDC as outlined in the Data Messaging Policy on the secure LRN website. The Gamma Phage Lysis Assay for the Identification of *Bacillus anthracis* Instructions for Use has also been updated to include a "procedure notes" section and "credit" section – which outlines the agencies involved in the development of the assay.
The package inserts for the positive and negative control materials distributed by CDC for the LRN - BC3366, BC3367 have been updated/ included to reflect the modifications outlined in the table above. Minor modifications to update contact emails were also included.
5. Design Control Activities Summary:
A "Declaration of Conformity with Design Controls" statement was submitted for the manufacturing facility and verification activities. The statements indicate that:
1. The manufacturing facility is in conformance with design control procedure requirements as specified in 21 CFR 820.30 and the records are available for review – signed by the Chief of the Scientific Products and Support Branch.
2. The validation activities, as required by the risk analysis, for the modification were performed by the designated individuals and the results demonstrated that the predetermined acceptance criteria were met - signed by a supervisory research microbiologist.
6. Truthful and Accuracy Statement, a 510(k) Summary or Statement, Package Inserts, Labels Instructions for Use and the Indications for Use Enclosure:
The labeling for this modified subject device has been reviewed to verify that the indication/intended use for the device is unaffected by the modification. In addition, the submitter's description of the particular modification(s) and the comparative information between the modified and unmodified devices demonstrate that the fundamental scientific technology has not changed. The submitter has provided the design control information as specified in The New 510(k) Paradigm and on this basis, I recommend the device be determined substantially equivalent to the previously cleared (or their preamendment) device.
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