Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set

K221658 · Centers for Disease Control and Prevention · PBK · Jun 10, 2022 · Microbiology

Device Facts

• Record ID: K221658
• Device Name: Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set
• Applicant: Centers for Disease Control and Prevention
• Product Code: PBK · Microbiology
• Decision Date: Jun 10, 2022
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 866.3315
• Device Class: Class 2

Indications for Use

The Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set is intended for the in vitro qualitative presumptive detection of non-variola Orthopoxvirus DNA extracted from human pustular or vesicular rash specimens and viral cell culture lysates submitted to a Laboratory Response Network (LRN) reference laboratory. The assay detects non-variola Orthopoxvirus DNA, including Vaccinia, Cowpox, Monkeypox and Ectromelia viruses at varying concentrations. This assay does not differentiate Vaccinia virus or Monkeypox virus from other Orthopoxviruses detected by this assay and does not detect Variola virus. Refer to the CDC algorithm, Acute, Generalized Vesicular or Pustular Rash Illness Testing Protocol in the United States for recommended testing and evaluation algorithms for patients presenting with acute, generalized pustular or vesicular rash illness. Results of this assay are for the presumptive identification of non-variola Orthopoxvirus DNA. These results must be used in conjunction with other diagnostic assays and clinical observations to diagnose Orthopoxvirus infection. The assay should only be used to test specimens with low/moderate risk of smallpox. If a high risk of smallpox exists, viral culture should not be attempted. Negative results obtained with this device do not preclude Variola virus infection and should not be used as the sole basis for treatment or other patient management decisions. Use is limited to Laboratory Response Network (LRN) designated laboratories.

Device Story

Device is a real-time PCR primer and probe set for qualitative detection of non-variola Orthopoxvirus DNA. Input: DNA extracted from human pustular/vesicular rash specimens or viral cell culture lysates. Principle: fluorogenic probe (FAM reporter/BHQ1 quencher) anneals to target sequence; Taq polymerase 5' nuclease activity cleaves reporter dye during extension, generating fluorescent signal monitored in real-time. Internal controls included to verify extraction and reagent function. Used in Laboratory Response Network (LRN) reference laboratories by trained personnel. Output: real-time fluorescence data indicating presence of non-variola Orthopoxvirus DNA. Results provide presumptive identification to be used alongside clinical observations and other diagnostic assays for patient management. Benefits: rapid presumptive identification of Orthopoxvirus infections.

Clinical Evidence

No clinical data provided. Analytical sensitivity (limit of detection) was determined via bench testing. Performance characteristics inquiries are directed to the CDC.

Technological Characteristics

Real-time PCR assay using fluorogenic probes (FAM/BHQ1). Employs Taq polymerase (heat-activated at 95°C). Requires real-time PCR instrumentation and software. Designed for use in LRN-designated laboratories. No specific materials or connectivity standards listed.

Indications for Use

Indicated for in vitro qualitative presumptive detection of non-variola Orthopoxvirus DNA in human pustular/vesicular rash specimens and viral cell culture lysates. Patient population: individuals presenting with acute, generalized pustular or vesicular rash illness. Contraindications: high risk of smallpox (viral culture should not be attempted).

Regulatory Classification

Identification

In vitro qualitative detection of non-variola Orthopoxvirus nucleic acids extracted from human specimens or viral culture.

Predicate Devices

• Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set (K181205)

Submission Summary (Full Text)

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FDA U.S. FOOD & DRUG ADMINISTRATION

# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY
ASSAY AND INSTRUMENT

## I Background Information:

A 510(k) Number
K221658

B Applicant
Centers for Disease Control and Prevention

C Proprietary and Established Names
Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set

D Regulatory Information
| Product Code(s) | Classification | Regulation Section | Panel |
| --- | --- | --- | --- |
| PBK | Class II | 21 CFR 866.3315 - Nucleic Acid Based Reagents For Detection Of Non-Variola Orthopoxviruses | MI - Microbiology |

## II Submission/Device Overview:

A Purpose for Submission:
Modification of device

B Measurand:
Non-variola Orthopoxvirus DNA target sequence

C Type of Test:
In vitro molecular diagnostic test

Food and Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993-0002
www.fda.gov

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III Intended Use/Indications for Use:

A Intended Use(s):
See Indications for Use below.

B Indication(s) for Use:
The Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set is intended for the in vitro qualitative presumptive detection of non-variola Orthopoxvirus DNA extracted from human pustular or vesicular rash specimens and viral cell culture lysates submitted to a Laboratory Response Network (LRN) reference laboratory. The assay detects non-variola Orthopoxvirus DNA, including Vaccinia, Cowpox, Monkeypox and Ectromelia viruses at varying concentrations. This assay does not differentiate Vaccinia virus or Monkeypox virus from other Orthopoxviruses detected by this assay and does not detect Variola virus. Refer to the CDC algorithm, Acute, Generalized Vesicular or Pustular Rash Illness Testing Protocol in the United States for recommended testing and evaluation algorithms for patients presenting with acute, generalized pustular or vesicular rash illness.

Results of this assay are for the presumptive identification of non-variola Orthopoxvirus DNA. These results must be used in conjunction with other diagnostic assays and clinical observations to diagnose Orthopoxvirus infection. The assay should only be used to test specimens with low/moderate risk of smallpox. If a high risk of smallpox exists, viral culture should not be attempted. Negative results obtained with this device do not preclude Variola virus infection and should not be used as the sole basis for treatment or other patient management decisions.

Use is limited to Laboratory Response Network (LRN) designated laboratories.

C Special Conditions for Use Statement(s):
Rx - For Prescription Use Only

Distribution of device is limited to designated laboratories in the Laboratory Response Network.

D Special Instrument Requirements:
Real-Time PCR Instrumentation and Software

IV Device/System Characteristics:

A Device Description:

The Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set uses a fluorogenic probe, consisting of an oligonucleotide with a reporter dye (FAM) attached to the 5' end and a quencher dye (BHQ1) attached at or near the 3' end. The probe anneals to a specific target sequence located between the forward and reverse primers. During the extension phase of the PCR cycle, the 5' nuclease activity of the Taq polymerase degrades the probe causing the reporter dye to separate from the quencher dye, thereby generating a fluorescent signal. With each cycle, additional reporter dye molecules are cleaved from their respective probes and the fluorescence intensity is monitored during the PCR in real-time. The Taq polymerase used in this assay is inactive at room temperature and is activated by incubation at 95°C, thus minimizing the production of nonspecific amplification products.

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Each extracted DNA sample is tested using the Non-variola Orthopoxvirus Real-time PCR Primer and Probe set along with an internal control primer and probe set(s) to demonstrate adequate DNA extraction, proper function of common reagents and equipment, and the absence of inhibitory substances.

## B Instrument Description Information:

Testing with the Non-variola Orthopoxvirus Real-time PCR Primer and Probe set is conducted using real-time PCR instrumentation and software.

## V Substantial Equivalence Information:

### A Predicate Device Name(s):

Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set

### B Predicate 510(k) Number(s):

K181205

### C Comparison with Predicate(s):

| Device & Predicate Device(s): | K221658 | K181205 |
| --- | --- | --- |
| Device Trade Name | Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set | Same |
| General Device Characteristic Similarities | | |
| Intended Use/Indications For Use | The Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set is intended for the in vitro qualitative presumptive detection of non-variola Orthopoxvirus DNA extracted from human pustular or vesicular rash specimens and viral cell culture lysates submitted to a Laboratory Response Network (LRN) reference laboratory. The assay detects non-variola Orthopoxvirus DNA, including Vaccinia, Cowpox, Monkeypox and Ectromelia viruses at varying concentrations. This assay does not differentiate Vaccinia virus or Monkeypox | Same |

K221658 - Page 3 of 6

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K221658 - Page 4 of 6
| | virus from other
Orthopoxviruses detected by
this assay and does not detect
Variola virus. Refer to the
CDC algorithm, Acute,
Generalized Vesicular or
Pustular Rash Illness Testing
Protocol in the United States
for recommended testing and
evaluation algorithms for
patients presenting with acute,
generalized pustular or
vesicular rash illness.

Results of this assay are for
the presumptive identification
of non-variola Orthopoxvirus
DNA. These results must be
used in conjunction with other
diagnostic assays and clinical
observations to diagnose
Orthopoxvirus infection. The
assay should only be used to
test specimens with
low/moderate risk of
smallpox. If a high risk of
smallpox exists, viral culture
should **not** be attempted.
Negative results obtained with
this device do not preclude
Variola virus infection and
should not be used as the sole
basis for treatment or other
patient management
decisions.

**Use of this assay is limited to**
**Laboratory Response**
**Network (LRN) designated**
**laboratories.** | |
| --- | --- | --- |
| Principle of Operation | Nucleic acid amplification
and fluorescent probe
detection | Same |
| Sample Types | • Vesicle fluid, skin,
crust, “roof”
• Dry or wet swab of
lesion (dry swab is | Same |

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K221658 - Page 5 of 6

| | preferred) • Touch prep (slide) of lesion • Fresh biopsy of pustule or vesicle (no formalin) • Viral cell culture lysates | |
| --- | --- | --- |
| Instrumentation and Software | Real-time PCR instrumentation and software | Same |

VI Standards/Guidance Documents Referenced:

N/A

VII Performance Characteristics (if/when applicable):

A Analytical Performance:

1. Precision/Reproducibility:

N/A

2. Analytical Specificity/Interference:

Inquiries regarding performance characteristics for the Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set should be directed to the Centers for Disease Control and Prevention.

3. Detection Limit:

The limit of detection for the Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set was determined through an analytical sensitivity study.

4. Assay Cut-Off:

N/A

B Comparison Studies:

1. Method Comparison with Predicate Device:

N/A

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2. Matrix Comparison:

N/A

C Clinical Studies:

Inquiries regarding performance characteristics for the Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set should be directed to the Centers for Disease Control and Prevention.

D Clinical Cut-Off:

N/A

E Expected Values/Reference Range:

N/A

VIII Proposed Labeling:

The labeling supports the finding of substantial equivalence for this device.

IX Conclusion:

The submitted information in this premarket notification is complete and supports a substantial equivalence decision.

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