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K Number
DEN140004
Device Name
QUIDEL MOLECULAR DIRECT HSV 1 +2/VZV ASSAY
Manufacturer
DIAGNOSTIC HYBRIDS, INC.
Date Cleared
2014-05-13

(81 days)

Product Code
PGI
Regulation Number
866.3309
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP Authorized
Intended Use
The Lyra™ Direct HSV 1 + 2/VZV Assay is an in vitro multiplex Real-Time PCR test for qualitative detection and differentiation of herpes simplex virus type 1, herpes simplex virus type 2, and varicella-zoster virus DNA isolated and purified from cutaneous or mucocutaneous lesion samples obtained from symptomatic patients suspected of active herpes simplex virus 1. herpes simplex virus 2 and/or varicella-zoster infection. The Lyra™ Direct HSV 1 + 2/VZV Assay is intended to aid in the diagnosis of herpes simplex virus 1, herpes simplex virus 2 and varicella-zoster virus active cutaneous or mucocutaneous infections. Negative results do not preclude herpes simplex virus 1, herpes simplex virus 2 and varicella-zoster virus infections and should not be used as the sole basis for diagnosis, treatment or other management decisions. The Lyra™ Direct HSV 1 + 2/VZV Assay is not intended for use with cerebrospinal fluid or to aid in the diagnosis of HSV or VZV infections of the central nervous system (CNS). The Lyra™ Direct HSV 1 + 2/VZV Assay is not intended for use in prenatal screening. The device is not intended for point-of-care use.
Device Description
The Lyra™ Direct HSV 1 + 2/VZV Assay detects viral nucleic acids from a patient sample. A multiplex Real-Time PCR reaction is carried out under optimized conditions in a single tube or well generating amplicons for HSV-1, HSV-2, VZV, and the Process Control (PRC). Identification of amplicons for HSV-1, HSV-2, VZV, and the PRC occurs by the use of target-specific primers and fluorescent-labeled probes that hybridize to conserved regions in the genomes of HSV-1, HSV-2, and VZV and to the PRC, respectively.
More Information

Not Found (De Novo request)

Not Found

No
The description focuses on Real-Time PCR technology and standard analytical and clinical performance metrics. There is no mention of AI, ML, or related concepts.

No.
This device is an in vitro diagnostic test designed to detect viral DNA, aiding in the diagnosis of infections. It does not provide treatment or directly alleviate symptoms; therefore, it is not a therapeutic device.

Yes

The "Intended Use / Indications for Use" section explicitly states that the assay "is intended to aid in the diagnosis of herpes simplex virus 1, herpes simplex virus 2 and varicella-zoster virus active cutaneous or mucocutaneous infections."

No

The device is an in vitro diagnostic (IVD) assay that involves reagents and a Real-Time PCR reaction, which are physical components, not solely software.

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 Lyra™ Direct HSV 1 + 2/VZV Assay is an in vitro multiplex Real-Time PCR test. It is intended for the qualitative detection and differentiation of viral DNA from patient samples to aid in the diagnosis of infections. This clearly aligns with the definition of an in vitro diagnostic device, which is used to examine specimens from the human body to provide information for diagnosis, treatment, or prevention of disease.
  • Device Description: The description details how the device works by detecting viral nucleic acids from a patient sample using a Real-Time PCR reaction. This process is performed outside of the body, which is characteristic of an in vitro test.
  • Sample Type: The device uses "cutaneous or mucocutaneous lesion samples obtained from symptomatic patients," which are specimens taken from the human body.
  • Performance Studies: The document describes extensive analytical and clinical performance studies conducted to evaluate the device's accuracy and reliability in detecting the target viruses in patient samples. This is a standard requirement for IVD devices seeking regulatory clearance.
  • Key Metrics: The performance studies report metrics like Sensitivity and Specificity, which are crucial for evaluating the diagnostic performance of an IVD.

All these points confirm that the Lyra™ Direct HSV 1 + 2/VZV Assay is designed and intended for use as an in vitro diagnostic device.

N/A

Intended Use / Indications for Use

The Lyra™ Direct HSV 1 + 2/VZV Assay is an in vitro multiplex Real-Time PCR test for qualitative detection and differentiation of herpes simplex virus type 1, herpes simplex virus type 2, and varicella-zoster virus DNA isolated and purified from cutaneous or mucocutaneous lesion samples obtained from symptomatic patients suspected of active herpes simplex virus 1. herpes simplex virus 2 and/or varicella-zoster infection. The Lyra™ Direct HSV 1 + 2/VZV Assay is intended to aid in the diagnosis of herpes simplex virus 1, herpes simplex virus type 2 and varicella-zoster virus active cutaneous or mucocutaneous infections. Negative results do not preclude herpes simplex virus 1, herpes simplex virus 2 and varicella-zoster virus infections and should not be used as the sole basis for diagnosis, treatment or other management decisions. The Lyra™ Direct HSV 1 + 2/VZV Assay is not intended for use with cerebrospinal fluid or to aid in the diagnosis of HSV or VZV infections of the central nervous system (CNS). The Lyra™ Direct HSV 1 + 2/VZV Assay is not intended for use in prenatal screening. The device is not intended for point-of-care use.

Product codes (comma separated list FDA assigned to the subject device)

PGI

Device Description

The Lyra™ Direct HSV 1 + 2/VZV Assay detects viral nucleic acids from a patient sample. A multiplex Real-Time PCR reaction is carried out under optimized conditions in a single tube or well generating amplicons for HSV-1, HSV-2, VZV, and the Process Control (PRC). Identification of amplicons for HSV-1, HSV-2, VZV, and the PRC occurs by the use of target-specific primers and fluorescent-labeled probes that hybridize to conserved regions in the genomes of HSV-1, HSV-2, and VZV and to the PRC, respectively.

Mentions image processing

Not Found

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

Not Found

Anatomical Site

cutaneous or mucocutaneous lesion samples

Indicated Patient Age Range

Not Found

Intended User / Care Setting

For prescription use only in accordance with 21 CFR 801.109. Not intended for point-of-care use.

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

A multi-center study was performed between April, 2013 and October, 2013 to evaluate the Lyra™ Direct HSV 1 + 2/VZV Assay using lesion swab specimens obtained from cutaneous or mucocutaneous lesions and submitted for HSV and/or VZV culture. These specimens were processed with the Lyra™ Direct HSV 1 + 2/VZV Assay kit and tested on the Life Technologies QuantStudio™ Dx, the Applied Biosystems® 7500 Fast Dx, and the Cepheid SmartCycler® II at three locations. Each specimen was also processed and inoculated into two (2) different cell culture systems within 72 hours of collection: one system for the isolation and identification of HSV-1 and HSV-2 and the other system for the isolation and identification of VZV. Cells isolated from the specimens were also stained for the presence of VZV.

The specimens were categorized as cutaneous (skin lesion, penis), or mucocutaneous (anorectal, vaginal/cervical, and oral lesion).

Clinical study sample sizes and results:

  • Life Technologies QuantStudio™ Dx:
    • Cutaneous Lesions:
      • HSV-1: 279 specimens (1 invalid, 278 analyzed).
      • HSV-2: 279 specimens (1 invalid, 278 analyzed).
      • VZV: 279 specimens (56 excluded due to HSV, 1 invalid, 222 analyzed).
    • Mucocutaneous Lesions:
      • HSV-1: 650 specimens (3 contaminated, 1 invalid, 646 analyzed).
      • HSV-2: 650 specimens (3 contaminated, 1 invalid, 646 analyzed).
      • VZV: 650 specimens (217 excluded due to HSV, 1 invalid, 432 analyzed).
  • Applied Biosystems® 7500 Fast Dx:
    • Cutaneous Lesions:
      • HSV-1: 279 specimens analyzed.
      • HSV-2: 279 specimens analyzed.
      • VZV: 279 specimens (56 excluded due to HSV, 223 analyzed).
    • Mucocutaneous Lesions:
      • HSV-1: 650 specimens (3 contaminated, 3 invalid, 644 analyzed).
      • HSV-2: 650 specimens (3 contaminated, 3 invalid, 644 analyzed).
      • VZV: 650 specimens (217 excluded due to HSV, 3 invalid, 430 analyzed).
  • Cepheid SmartCycler® II:
    • Cutaneous Lesions:
      • HSV-1: 279 specimens (1 invalid, 278 analyzed).
      • HSV-2: 279 specimens (1 invalid, 278 analyzed).
      • VZV: 279 specimens (56 excluded due to HSV, 1 invalid, 222 analyzed).
    • Mucocutaneous Lesions:
      • HSV-1: 650 specimens (3 contaminated, 4 invalid, 643 analyzed).
      • HSV-2: 650 specimens (3 contaminated, 4 invalid, 643 analyzed).
      • VZV: 650 specimens (217 excluded due to HSV, 4 invalid, 429 analyzed).

Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)

1. Analytical Performance:

  • Reproducibility/Precision: Evaluated at 3 laboratory sites (two external, one in-house) using a panel of 6 simulated samples (medium positive, low positive, high negative, negative for HSV-1, HSV-2, VZV). Panels and controls were tested on all three instruments (Life Technologies QuantStudio™ Dx, Applied Biosystems® 7500 Fast Dx, Cepheid SmartCycler® II System) by 2 operators for 5 days (triplicate testing x 2 operators x 5 days x 3 sites = 90 results per level for each virus). Precision was also assessed with a blinded four-member panel (HSV-1, HSV-2, VZV positive and negative) tested by 2 operators, twice a day for 12 days on all three instruments. Results showed consistent detection rates and acceptable coefficient of variation (CV%) across sites and instruments, with most positive samples detected at 100% and negative samples at 0%. High negative samples showed some variability in detection rates.
  • Kit Stability: Real-time study using 3 production lots stored at 2° to 8°C. Test protocol used 2x LoD virus dilutions of HSV-1, HSV-2, VZV, tested in triplicate on the Applied Biosystems® 7500 Fast Dx. Ct values must be within 3 Cts of initial values. Data demonstrated stability up to 243 days.
  • Rehydrated Master Mix Stability: Study on Applied Biosystems® 7500 Fast Dx with rehydrated Master Mix stored at -20°C, 2° to 8°C, and room temperature. Stability claims: RT (1.5-4hrs), 2-8°C (24hrs), -20°C (76hrs).
  • Processed Sample Stability: Evaluated on Applied Biosystems® 7500 Fast Dx with HSV-1, HSV-2, VZV stocks at 2x LoD stored at RT, 2-8°C, -20°C, and -70°C. Samples were stable for 48 hours at RT (20-25°C) and 2° to 8°C, and 31 days at -20°C and -70°C with little or no Ct shift.
  • Detection limit (LoD): Determined on each instrument in three separate studies using quantified stocks of two strains of HSV-1, two strains of HSV-2, and two strains of VZV serially diluted in negative matrix. LoD is defined as the lowest concentration at which 95% of all replicates tested positive. Performance was substantially equivalent on all three platforms (LoD within three doubling dilutions).
  • Analytical Reactivity: Study on Applied Biosystems® 7500 Fast Dx to verify detection of multiple strains of HSV-1 (4 strains), HSV-2 (5 strains), and VZV (7 strains) at concentrations near the LoD. All tested strains were detected.
  • Analytical Specificity (Cross-Reactivity and Inhibition): Study on Applied Biosystems® 7500 Fast Dx to evaluate performance in the presence of 70 other microorganisms (viruses, bacteria) and 26 potentially interfering substances common in lesion specimens. Each microorganism was tested in negative matrix (for cross-reactivity) or with 2x LoD HSV-1, HSV-2, VZV (for inhibition). None of the microorganisms cross-reacted or interfered with detection. An in silico analysis for Treponema pallidum confirmed no cross-reactivity.
  • Competitive Interference: Study performed on all three instruments to evaluate if competitive interference exists when HSV-1, HSV-2, and VZV are present in the same reaction. HSV-1, HSV-2, and VZV stocks at 2x LoD were tested with varying amounts of other analytes (2x, 10x, 100x, 1000x, 10,000x LoD). No competitive interference was observed on any instrument.
  • Sample Stability Studies: Assessment of fresh and frozen samples on Applied Biosystems® 7500 Fast Dx using contrived specimens at 2x and 5x LoD, stored at -20°C and 2° to 8°C for up to 8 days. >95% agreement was observed, indicating specimens are stable for up to 7 days at 2° to 8°C or -20°C.
  • Comparison of Transport Media: Study on Applied Biosystems® 7500 Fast Dx to determine impact of UTM, M4, M4-RT, M5, and M6 transport media. No significant difference in assay performance was seen.
  • Carry-over Contamination: Evaluation on each instrument using a 96-sample panel (48 high positives alternating with 48 negatives), repeated over 5 days. No cross-contamination or amplicon carry-over occurred.

2. Clinical Studies:
A multi-center study evaluated the Lyra™ Direct HSV 1 + 2/VZV Assay against FDA-cleared ELVIS cell culture system for HSV-1/HSV-2 and DSFA with cell culture for VZV.

  • Performance on Life Technologies QuantStudio™ Dx:

    • Cutaneous Lesions (N=278 after exclusions):
      • HSV-1: Sensitivity 100% (24/24), Specificity 98.4% (250/254)
      • HSV-2: Sensitivity 100% (35/35), Specificity 96.3% (234/243)
      • VZV: Sensitivity 100% (27/27), Specificity 95.9% (187/195)
    • Mucocutaneous Lesions (N=646 after exclusions):
      • HSV-1: Sensitivity 97.1% (100/103), Specificity 97.1% (527/543)
      • HSV-2: Sensitivity 100% (95/95), Specificity 96.2% (530/551)
      • VZV: Sensitivity 100% (4/4), Specificity 98.8% (423/428)

  • Performance on Applied Biosystems® 7500 Fast Dx:

    • Cutaneous Lesions (N=279):
      • HSV-1: Sensitivity 100% (24/24), Specificity 98.8% (252/254)
      • HSV-2: Sensitivity 97.1% (34/35), Specificity 96.7% (236/244)
      • VZV: Sensitivity 96.3% (26/27), Specificity 95.9% (189/196)
    • Mucocutaneous Lesions (N=644 after exclusions):
      • HSV-1: Sensitivity 95.1% (98/103), Specificity 98.2% (531/541)
      • HSV-2: Sensitivity 97.9% (93/95), Specificity 97.1% (533/549)
      • VZV: Sensitivity 100% (4/4), Specificity 99.3% (423/426)

  • Performance on Cepheid SmartCycler® II:

    • Cutaneous Lesions (N=278 after exclusions):
      • HSV-1: Sensitivity 100% (24/24), Specificity 98.8% (251/254)
      • HSV-2: Sensitivity 100% (35/35), Specificity 96.7% (235/243)
      • VZV: Sensitivity 100% (27/27), Specificity 94.9% (185/195)
    • Mucocutaneous Lesions (N=643 after exclusions):
      • HSV-1: Sensitivity 98.1% (101/103), Specificity 97.2% (525/540)
      • HSV-2: Sensitivity 98.9% (94/95), Specificity 97.1% (532/548)
      • VZV: Sensitivity 100% (4/4), Specificity 98.8% (420/425)

Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)

See "Summary of Performance Studies" for detailed sensitivity and specificity results.

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.

Not Found (De Novo request)

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

§ 866.3309 Herpes virus nucleic acid-based cutaneous and mucocutaneous lesion panel.

(a)
Identification. A herpes virus nucleic acid-based cutaneous and mucocutaneous lesion panel is a qualitative in vitro diagnostic device intended for the simultaneous detection and differentiation of different herpes viruses in cutaneous and mucocutaneous lesion samples from symptomatic patients suspected of Herpetic infections. Negative results do not preclude infection and should not be used as the sole basis for treatment or other patient management decisions. The assay is not intended for use in cerebrospinal fluid samples.(b)
Classification. Class II (special controls). The special controls for this device are:(1) Premarket notification submissions must include detailed documentation for the device description, including the device components, ancillary reagents required but not provided, and a detailed explanation of the methodology including primer design and selection.
(2) Premarket notification submissions must include detailed documentation from the following analytical and clinical performance studies: Analytical sensitivity (Limit of Detection), reactivity, inclusivity, precision, reproducibility, interference, cross reactivity, carry-over, and cross contamination.
(3) Premarket notification submissions must include detailed documentation of a clinical study using lesion samples in which Herpes Simplex Virus 1, Herpes Simplex Virus 2, or Varicella Zoster Virus DNA detection was requested. The study must compare the device performance to an appropriate well established reference method.
(4) A detailed explanation of the interpretation of results and acceptance criteria must be included in the device's 21 CFR 809.10(b)(9) compliant labeling.
(5) The device labeling must include a limitation statement that reads: “The device is not intended for use with cerebrospinal fluid or to aid in the diagnosis of HSV or VZV infections of the central nervous system (CNS).”
(6) Premarket notification submissions must include quality assurance protocols and a detailed documentation for device software, including, but not limited to, standalone software applications and hardware-based devices that incorporate software.
(7) The risk management activities performed as part of the manufacturer's 21 CFR 820.30 design controls must document an appropriate end user device training program that will be offered as part of efforts to mitigate the risk of failure to correctly operate the instrument.

0

EVALUATION OF AUTOMATIC CLASS III DESIGNATION FOR Lyra™ Direct HSV 1 + 2/VZV Assay

DECISION SUMMARY

A. 510(k) Number:

K133448

B. Purpose for Submission:

De novo request for evaluation of automatic class III designation for the Lyra™ Direct HSV 1 + 2/VZV Assay

C. Measurand:

Target DNA sequences from conserved regions of the herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2) and varicella-zoster virus (VZV) genes.

D. Type of Test:

A real-time Polymerase Chain Reaction (PCR) test for qualitative detection and differentiation of HSV-1, HSV- 2, and VZV DNA isolated and purified from cutaneous or mucocutaneous lesion samples.

E. Applicant:

Quidel Corporation.

F. Proprietary and Established Names:

Lyra™ Direct HSV 1 + 2/VZV Assay

G. Regulatory Information:

  • 21 CFR 866.3309 1. Regulation:
    1. Classification: Class II (special controls)
    1. Product code: PGI
    1. Panel: Microbiology (83)

1

H. Intended Use:

1. Intended use(s):

The Lyra™ Direct HSV 1 + 2/VZV Assay is an in vitro multiplex Real-Time PCR test for qualitative detection and differentiation of herpes simplex virus type 1, herpes simplex virus type 2, and varicella-zoster virus DNA isolated and purified from cutaneous or mucocutaneous lesion samples obtained from symptomatic patients suspected of active herpes simplex virus 1. herpes simplex virus 2 and/or varicella-zoster infection. The Lyra™ Direct HSV 1 + 2/VZV Assay is intended to aid in the diagnosis of herpes simplex virus 1, herpes simplex virus 2 and varicella-zoster virus active cutaneous or mucocutaneous infections. Negative results do not preclude herpes simplex virus 1, herpes simplex virus 2 and varicella-zoster virus infections and should not be used as the sole basis for diagnosis, treatment or other management decisions. The Lyra™ Direct HSV 1 + 2/VZV Assay is not intended for use with cerebrospinal fluid or to aid in the diagnosis of HSV or VZV infections of the central nervous system (CNS). The Lyra™ Direct HSV 1 + 2/VZV Assay is not intended for use in prenatal screening. The device is not intended for point-of-care use.

    1. Indication(s) for use:
      Same as intended use
    1. Special conditions for use statement(s):
      For prescription use only in accordance with 21 CFR 801.109.
    1. Special instrument requirements:
      To be used with: Life Technologies QuantStudio™ Dx (software version 1.0) Applied Biosystems® 7500 Fast Dx (software version 1.4) Cepheid SmartCycler® II System (software version 3.0b)

I. Device Description:

The Lyra™ Direct HSV 1 + 2/VZV Assay detects viral nucleic acids from a patient sample. A multiplex Real-Time PCR reaction is carried out under optimized conditions in a single tube or well generating amplicons for HSV-1, HSV-2, VZV, and the Process Control (PRC). Identification of amplicons for HSV-1, HSV-2, VZV, and the PRC occurs by the use of target-specific primers and fluorescent-labeled probes that hybridize to conserved regions in the genomes of HSV-1, HSV-2, and VZV and to the PRC, respectively.

2

TargetDye
HSV-1FAM
HSV-2CAL Fluor® Orange 560
VZVCAL Fluor® Red 610
PRCQuasar® 670

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The following table and list describe: the reagents provided in the kit, the materials which are required but not provided with the kit and the optional reagents and materials.

Materials Provided With The Kit:

The Lyra™ Direct HSV 1 + 2/VZV Assay kit consists of the following:

  • Rehydration Solution -
  • Process Buffer Part M5050 (contains the PRC) -
  • Lyra™ Direct HSV 1 + 2/VZV Master Mix Part M5012 -
  • Lyophilized Contents:
    • o DNA polymerase enzyme
    • Primers and probes o
    • dNTPs O
    • o Stabilizers

Materials Required But Not Provided:

  • Micropipettors (range between 2 to 20 uL and 20 to 200 uL) -
  • Non-aerosol pipette tips -
  • Life Technologies OuantStudio™ Dx or the Applied Biosystems® 7500 Fast Dx -
  • Applied Biosystems Fast Dx 96 well PCR plate -
  • Optical plate films -
  • -Plate centrifuge for Applied Biosystems 96 well plate
  • Dry heating block, capable of heating 1.5 mL tubes at 60℃ for 5 minutes -
  • Empty microcentrifuge tubes -

Or

  • Micropipettors (range between 2 to 20 uL and 20 to 200 uL) -
  • -Non-aerosol pipette tips
  • Cepheid SmartCycler® II -
  • SmartCycler disposables -
  • -SmartCycler centrifuge
  • -Smartcycler reaction tube racks. Dry heating block, capable of heating 1.5 mL tubes at 60°C for 5 minutes.
  • -Empty microcentrifuge tubes

Optional Materials:

  • Positive controls for HSV-1, HSV-2 and VZV (i.e., Lyra™ Direct HSV 1 + 2/VZV -Control Set which serves as an external assay control)

3

J. Standard/Guidance Documents Referenced:

The following documents were referenced in one or more of the Guidance Documents above:

    1. CLSI EP17-A: Guidance for Protocols for Determination of Limits of Detection and Limits of Quantitation (Vol. 2, No. 34) (Oct 2004).
    1. CLSI MM13-A: Guidance for the Collection, Transport, Preparation and Storage of Specimens for Molecular Methods (Vol. 25. No. 31) (Dec 2005).
    1. CLSI EP7-A2: Guidance for Interference Testing in Clinical Chemistry (Vol. 25, No.27 Second Ed) (Nov 2005).
    1. CLSI EP12-A: Guidance for User Protocol for Evaluation of Qualitative Test Performance (Vol. 22, No. 14) (Sept 2002).
    1. CLSI MM6-A: Guidance for the Quantitative Molecular Methods for Infectious Diseases (Vol. 23, No.28) (Oct 2003).
    1. CLSI EP5-A2: Guidance for Evaluation of Precision Performance of Quantitative Measurement Methods (Vol. 24, No. 25 Second Ed.) (Aug 2004).

K. Test Principle:

The Lyra™ Direct HSV 1 + 2/VZV assay is based on TaqMan® chemistry and uses an enzyme with DNA polymerase and 5'-3' exonuclease activities. During DNA amplification. this enzyme cleaves the probe bound to the complementary DNA sequence, separating the quencher dye from the reporter dye. This step generates an increase in fluorescent signal upon excitation by a light source of the appropriate wavelength. With each cycle, additional dye molecules are separated from their quenchers resulting in additional signal. If sufficient

4

fluorescence is achieved on the Life Technologies QuantStudio™ Dx, the Applied Biosystems® 7500 Fast Dx, or the Cepheid SmartCycler® II System, the sample is reported as positive for the detected nucleic acid.

The following is a summary of the procedure:

Sample Collection: Obtain lesion swabs using standard techniques from symptomatic patients. Transport, store, and process these specimens according to established laboratory procedures.

Sample Preparation: Remove 100 uL of each clinical specimen from the original collection tube and place into a clean microcentrifuge tube. Heat at 60°C for 5 minutes, then remove from heat and add 25 uL of Process Buffer within 60 minutes according to the detailed instructions for use. The Process Buffer contains a buffer and diluents as well as the PRC. The PRC serves to monitor in the prepared specimen, assures that adequate amplification has taken place, and confirms that the overall process was performed correctly.

Rehydration of Master Mix: Rehydrate the lyophilized Master Mix using 135 uL of Rehydration Solution. The Master Mix contains oligonucleotide primers, fluorophore and quencher-labeled probes targeting conserved regions of HSV-1, and VZV, as well as the PRC sequence.

Nucleic Acid Amplification and Detection: Add 15 uL of the rehydrated Master Mix to each reaction tube or plate well. Then add 5 uL of nucleic acids (specimen with PRC) to the plate well or appropriately labeled reaction tube. Place the plate or tube into either the QuantStudio™ Dx, Applied Biosystems® 7500 Fast Dx or SmartCycler® II instruments, respectively. Once the reaction tube or plate is added to the instrument, initiate the assay protocol. This protocol initiates amplification of the DNA targets.

L. Performance Characteristics (if/when applicable):

1. Analytical performance:

a. Reproducibility/ Precision

Reproducibility: The reproducibility of the Lyra™ Direct HSV 1 + 2/VZV Assay was evaluated at 3 laboratory sites (two external, one in-house). Reproducibility was assessed using a panel of 6 simulated samples that include medium positive, low positive, high negative and negative HSV-1, HSV-2, and VZV samples.

The panels and controls were processed and tested on the Life Technologies QuantStudio™ Dx, the Applied Biosystems® 7500 Fast Dx, and the Cepheid SmartCycler® II System. Panels and controls were tested at each site by 2 operators for 5 days (triplicate testing x 2 operators x 5 days x 3 sites = 90 results per level for each virus).

5

Reproducibility Results - Life Technologies QuantStudio™ Dx
PanelSite 1Site 2Site 3
Combined Site Data
Member
IDRate of
DetectionAVE
Ct%
CVRate of
DetectionAVE
Ct%
CVRate of
DetectionAVE
Ct%
CVRate of
DetectionAVE
Ct%CV
HSV-1
High
Negative10/3037.04.916/3034.58.917/3034.07.643/9034.88.2
HSV-1
Low
Positive30/3029.81.630/3029.02.630/3029.53.690/9029.42.9
HSV-1
Moderate
Positive30/3028.31.930/3027.32.430/3027.93.790/9027.83.1
HSV-1
Negative0/30N/AN/A0/29*N/AN/A0/30N/AN/A0/89*N/AN/A
HSV-2
High
Negative30/3034.83.030/3031.94.728/3034.16.288/9033.66.0
HSV-2
Low
Positive30/3032.81.430/3032.02.330/3031.83.690/9032.22.9
HSV-2
Moderate
Positive30/3030.83.830/3029.82.830/3030.84.290/9030.53.9
HSV-2
Negative0/30N/AN/A0/29*N/AN/A0/30N/AN/A0/89*N/AN/A
VZV High
Negative9/3037.44.210/3035.26.45/3034.46.624/9035.96.5
VZV Low
Positive30/3029.21.730/3028.71.229/3029.95.589/9029.33.7
VZV
Moderate
Positive30/3027.61.330/3027.21.030/3027.72.690/9027.52.9
VZV
Negative0/30N/AN/A0/29*N/AN/A0/30N/AN/A0/89*N/AN/A
HSV-1
Positive
Control30/3027.42.630/3025.10.930/3026.82.790/9026.47.0
HSV-2
Positive
Control30/3026.76.630/3029.81.530/3025.43.790/9022.87.9
VZV
Positive
Control30/3022.113.430/3020.00.830/3021.14.590/9021.19.2
Negative
Control0/30N/AN/A0/30N/AN/A0/30N/AN/A0/90N/AN/A
  • One replicate's PRC was not detected. The replicate was reported as invalid.

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Reproducibility Results - Applied Biosystems® 7500 Fast Dx
Panel
Member
IDRate of
DetectionAVE
Ct%
CVRate of
DetectionAVE
Ct%
CVRate of
DetectionAVE
Ct%
CVRate of
DetectionAVE
Ct%CV
HSV-1
High
Negative9/3036.23.69/3035.010.112/2936.56.030/8936.17.6
HSV-1
Low
Positive30/3030.31.830/3030.33.430/3030.22.690/9030.32.7
HSV-1
Moderate
Positive30/3028.82.430/3028.52.630/3029.58.190/9028.95.4
HSV-1
Negative0/30N/AN/A0/30N/AN/A0/30N/AN/A0/90N/AN/A
HSV-2
High
Negative30/3035.43.730/3034.25.824/3036.06.084/9035.25.5
HSV-2
Low
Positive30/3032.84.230/3033.63.830/3032.75.990/9033.04.8
HSV-2
Moderate
Positive30/3031.22.130/3031.32.930/3031.94.390/9031.53.4
HSV-2
Negative0/30N/AN/A0/30N/AN/A0/30N/AN/A0/90N/AN/A
VZV High
Negative0/30N/AN/A3/3033.86.20/30N/AN/A3/9033.86.2
VZV Low
Positive29/3031.54.429/3031.54.630/3032.16.288/9031.75.2
VZV
Moderate
Positive30/3029.42.530/3029.22.130/3030.99.190/9029.86.2
VZV
Negative0/30N/AN/A0/30N/AN/A0/30N/AN/A0/90N/AN/A
HSV-1
Positive
Control30/3027.111.630/3025.91.330/3026.22.290/9026.47.2
HSV-2
Positive
Control30/3026.18.130/3024.91.230/3025.72.090/9025.65.2
VZV
Positive
Control30/3023.613.230/3021.81.130/3022.11.790/9022.58.6
Negative
Control0/30N/AN/A0/30N/AN/A0/30N/AN/A0/90N/AN/A

7

Reproducibility Results - Cepheid SmartCycler® II
PanelSite 1Site 2Site 3Combined Site Data
Member
IDRate of
DetectionAVE
Ct%
CVRate of
DetectionAVE
Ct%
CVRate of
DetectionAVE
Ct%
CVRate of
DetectionAVE
Ct%CV
HSV-1
High
Negative5/3037.81.95/3033.47.513/3035.32.423/3035.46.0
HSV-1
Low
Positive30/3031.31.330/3031.04.530/3031.52.490/9031.33.1
HSV-1
Moderate
Positive29/29*29.42.930/3028.94.230/3030.02.489/89*29.53.6
HSV-1
Negative0/30N/AN/A0/30N/AN/A0/30N/AN/A0/90N/AN/A
HSV-2
High
Negative24/3038.55.127/3036.66.517/3037.34.468/9037.45.8
HSV-2
Low
Positive30/3036.23.329/3035.82.530/3035.84.989/9036.03.7
HSV-2
Moderate
Positive29/29*33.61.630/3033.34.630/3033.83.489/89*33.62.5
HSV-2
Negative0/30N/AN/A0/30N/AN/A0/30N/AN/A0/90N/AN/A
VZV High
Negative0/30N/AN/A1/30N/AN/A0/30N/AN/A1/90N/AN/A
VZV Low
Positive29/3033.47.029/3032.72.830/3036.210.788/9034.18.9
VZV
Moderate
Positive29/29*30.92.330/3030.61.130/3033.48.589/89*31.66.7
VZV
Negative0/30N/AN/A0/30N/AN/A0/30N/AN/A0/90N/AN/A
HSV-1
Positive
Control30/3027.68.630/3026.41.830/3027.42.290/9027.25.6
HSV-2
Positive
Control30/3028.07.030/3026.51.830/3028.19.390/9027.57.3
VZV
Positive
Control30/3024.712.130/3022.91.130/3023.71.990/9023.87.9
Negative
Control0/30N/AN/A0/30N/AN/A0/30N/AN/A0/90N/AN/A
  • One replicate's PRC was not detected. The replicate was reported as invalid.

Precision: For the Precision/Within Laboratory Repeatability study, a blinded four-member panel consisting of HSV-1, HSV-2, and VZV positive and negative samples was tested by two (2) operators (Op 1 and Op 2), twice a day (2X) for twelve (12) days on all three instruments.

8

Life Technologies QuantStudio™ Dx Results Summary
TargetPositive
Control5X LoD2X LoD95% agreement between the results obtained with the contrived specimens on the day of preparation and after storage at 29 to 8°C for 7 and 8 days. There was >95% agreement between the results obtained with the contrived specimens on the day of preparation and after storage at -20℃ for 7 and 8 days. Based on this study, specimens may be stored at either 2° to 8°C or -20°C for up to 7days with no effect on the performance of the Lyra™ Direct HSV 1 + 2/VZV Assay.

20

Comparison of Transport Media j.

The following study was performed to determine whether various transport media impact the performance in the Lyra™ Direct HSV 1 + 2/VZV Assay on the Applied Biosystems 7500® Fast Dx instrument. HSV-1, HSV-2, and VZV virus stocks were diluted to 2x LoD concentrations using negative matrix collected in five different media: UTM. M4. M4-RT. M5. and M6. The acceptance criteria for this study were met for all media. The Lyra™ Direct HSV 1 + 2/VZV Assay can be used with samples collected in UTM, M4, M4RT, M5, or M6 transport media.

  • k. Carry-over Contamination
    An evaluation of potential carry-over contamination during the sample processing and amplification steps was performed on each instrument. The study was conducted using a 96-sample panel consisting of 48 high positives and 48 negative specimens. Each high positive specimen contained 1.00E+05 TCID50/mL of each analyte (combined into one specimen). The negative specimen was negative matrix. The high positive samples were analyzed in series alternating with the negative samples. The testing was repeated over a 5-day period. Over the course of 5days, cross-contamination and amplicon carry-over did not occur with the Lyra™ Direct HSV 1+2/VZV Assay on any of the three instruments.

    1. Comparison studies:
    • a. Method comparison with predicate device:

Not applicable. Refer to the Clinical Studies section of this document.

  • b. Matrix comparison:
    Not applicable.

    1. Clinical studies:
      A multi-center study was performed between April, 2013 and October, 2013 to evaluate the Lyra™ Direct HSV 1 + 2/VZV Assay using lesion swab specimens obtained from cutaneous or mucocutaneous lesions and submitted for HSV and/or VZV culture. These specimens were processed with the Lyra™ Direct HSV 1 + 2/VZV Assay kit and tested on the Life Technologies QuantStudio™ Dx, the Applied Biosystems® 7500 Fast Dx, and the Cepheid SmartCycler® II at three locations. Each specimen was also processed and inoculated into two (2) different cell culture systems within 72 hours of collection: one system for the isolation and identification of HSV-1 and HSV-2 and the other system for the isolation and identification of VZV. Cells isolated from the specimens were also stained for the presence of VZV.

The specimens were categorized as cutaneous (skin lesion, penis), or mucocutaneous

21

Combined Study – Age and Gender Distribution (Cutaneous)
GenderFemaleMale
Age
60 years*565

Life Technologies QuantStudio™ Dx

*1 Specimen was invalid when tested on the Life Technologies QuantStudio™ Dx. It has been removed from analysis.

Expected Values (Cutaneous) (N=279)*
HSV- 1HSV-2VZV
Total #Total PositivePrevalenceTotal #Total PositivePrevalenceTotal #Total PositivePrevalence
skin lesion213*2411.3%213*2712.7%213*3516.4%

31

genital - penis6.2%26.2%1.5%
1. 8 74Carlos Company of Children Company of Children Company Company Company Company Company Company Company Company Company Company Company Company Company Company Comments of Chi(Comments of the may be and the comments of the comments of

*1 Specimen was invalid when tested on the Life Technologies QuantStudio™ Dx. It has been removed from analysis.

Expected Values (Mucocutaneous) (N=650)*
HSV- 1HSV-2VZV
AgeTotal #Total PositivePrevalenceTotal #Total PositivePrevalenceTotal #Total PositivePrevalence
60 years5347.5%531018.9%5323.8%

*1 Specimen was invalid when tested on the Life Technologies QuantStudio™ Dx. It has been removed from analysis.

Expected Values (Mucocutaneous) (N=650)*
HSV- 1HSV-2VZV
Total #Total PositivePrevalenceTotal #Total PositivePrevalenceTotal #Total PositivePrevalence
anorectal26415.4%26623.1%2613.8%
genital –
vaginal/cervical473*7515.9%473*10722.6%473*40.8%
Nares9222.2%90N/A90N/A
Ocular60N/A60N/A6116.6%
oral lesion1353525.9%13532.2%13532.2%

*1 Specimen was invalid when tested on the Life Technologies QuantStudio™ Dx. It has been removed from analysis.

Applied Biosystems® 7500 Fast Dx

Expected Values (Cutaneous) (N=279)
HSV- 1HSV-2VZV
. AgeTotal

| Total

Positive | Prevalence | Total # | Total
Positive | Prevalence | Total # | Total
Positive | Prevalence | |
| 60 years | 57 | ব | 7.0% | 57 | 8 | 14.0% | 57 | 10 | 17.5% | |

Expected Values (Cutaneous) (N=279)
HSV- 1HSV-2VZV
Total #Total
PositivePrevalenceTotal #Total
PositivePrevalenceTotal #Total
PositivePrevalence
skin lesion2142411.2%2142612.1%2143315.4%
genital - penis6534.6%651624.6%650N/A
Expected Values (Mucocutaneous) (N=650)*
AgeHSV-1HSV-2VZV

32

| | Total
1 # | Total
Positive | Prevalence | Total # | Total
Positive | Prevalence | Total # | Total
Positive | Prevalence |
|-----------------|--------------|-------------------|------------|---------|-------------------|------------|---------|-------------------|------------|
| 60 years | 53 | 3 | 5.7% | 53 | 10 | 18.9% | 53 | 1 | 1.9% |

  • Three (3) specimens were invalid when tested on the Applied Biosystems® 7500 Fast Dx. They have been removed from analysis.
Expected Values (Mucocutaneous) (N=656)*
HSV- 1HSV-2VZV
Total #Total PositivePrevalenceTotal #Total PositivePrevalenceTotal #Total PositivePrevalence
anorectal26415.4%26623.1%2613.8%
genital –
vaginal/cervical471*7014.9%471*10221.7%471*30.6%
Nares9111.1%90N/A90N/A
Ocular60N/A60N/A6116.6%
oral lesion1353324.4%13510.7%13521.5%
  • Three (3) specimens were invalid when tested on the Applied Biosystems® 7500 Fast Dx. They have been removed from analysis.

Cepheid SmartCycler® II System

Expected Values (Cutaneous) (N=279)*
HSV- 1HSV-2VZV
AgeTotal #Total PositivePrevalenceTotal #Total PositivePrevalenceTotal #Total PositivePrevalence
60 years5735.3%57915.8%571119.3%

*One (1) specimen was invalid when tested on the Cepheid SmartCycler® II. It has been removed from analysis.

Expected Values (Cutaneous) (N=279)*
HSV- 1HSV-2VZV
Total #Total
PositivePrevalenceTotal #Total
PositivePrevalenceTotal #Total
PositivePrevalence
skin lesion213*2210.3%213*2612.2%213*3717.4%
genital - penis6557.7%651726.2%650N/A

*One (1) specimen was invalid when tested on the Cepheid SmartCycler® II. It has been removed from analysis.

Expected Values (Mucocutaneous) (N=650)*
HSV- 1HSV-2VZV
AgeTotal #Total PositivePrevalenceTotal #Total PositivePrevalenceTotal #Total PositivePrevalence
≤ 5 years18527.8%180N/A180N/A
6 to 21 years1302922.3%1302418.5%13010.8%
22 to 59 years*4457817.5%4457617.1%44561.3%
≥ 60 years5347.5%531018.9%5323.8%

*Four (4) specimens were invalid when tested on the Cepheid SmartCycler® II. They have been removed from analysis.

33

Expected Values (Mucocutaneous) (N=650)*
HSV-1HSV-2VZV
Total #Total PositivePrevalenceTotal #Total PositivePrevalenceTotal #Total PositivePrevalence
anorectal26415.4%26623.1%2613.8%
genital –
vaginal/cervical470*7516.0%470*10321.9%470*40.9%
nares9222.2%90N/A90N/A
ocular60N/A60N/A6116.6%
oral lesion1353525.9%13510.7%13532.2%

*Four (4) specimens were invalid when tested on the Cepheid SmartCycler® II. They have been removed from
analysis.

34

M. Instrument Names:

The manufacturer intends to market this assay for use with three instrument platforms:

  • Life Technologies QuantStudio™ Dx -
  • Applied Biosystems® 7500 Fast Dx -
  • Cepheid SmartCycler® II System -

N. System Description:

    1. Modes of Operation:
    1. Modes of Operation

For this application, Quidel assessed the software for each of the three systems and provided documentation on these platforms per FDA Guidance for Industry, FDA Reviewers and Compliance- Off-The-Shelf Software Use in Medical Devices. The firm's assessment determined that the software packages, when used as intended, presents a Moderate Level of Concern. Ouidel states thev have full access to the instruments with the current software. Each instrument is under a quality service plan with the manufacturers that includes both maintenance and software upgrades and will be in effect for the life of the Lyra™ Direct HSV 1+2/VZV Assay.The Applied Biosystems 7500 Fast Dx Real-Time PCR Instrument with the SDS Software version 1.4 is a real-time nucleic acid amplification and detection system that measures fluorescence signal output from dual-labeled hydrolysis probes. The Sequence Detection Software (SDS) version 1.4 for the 7500 Fast Dx Instrument is used for instrument control, data collection and data analysis. The software can analyze cycle-by-cycle real-time signals from the sample. Life Technologies QuantStudio™ Dx uses fluorescent-based polymerase chain reaction (PCR) reagents to provide quantitative detection of target nucleic acid sequences (targets) using real-time analysis. After a test run, the version 1.0 software uses calibration data to determine the location and intensity of the fluorescent signals in each read, the dye associated with each fluorescent signal, and the significance of the signal. The Cepheid SmartCycler II with the Software version 3.0b is a real-time nucleic acid amplification and detection system that measures fluorescence signal output from dual-labeled hydrolysis probes. Software version 3.0b is used for instrument control, data collection and data analysis. The software can measure cycle-by-cycle real-time signals from the sample.

    1. Specimen Identification: Not Applicable
    1. Specimen Sampling and Handling:

Specimens used for the validation of the Lyra™ Direct HSV 1 + 2/VZV Assay were obtained using standard techniques from patients with lesion infection symptoms. These specimens were collected, transported, stored, and processed according to CLSI M41-A.2. Samples can be stored at 2° to 8°C or -20°C for up to 7 days prior to processing. The performance of the assay was evaluated using: M4, M4-RT, M5, M6, and UTM. No

35

significant difference in assay performance was seen between the five different types of viral transport media. Prepared samples can be stored for 48 hours when stored at 2º to 8°C, 31 days when stored at either -20°C or -70°C.

    1. Calibration:
      Calibration is not required or recommended.
    1. Quality Control:
      The Lyra™ Direct HSV 1 + 2/VZV Assay incorporates several controls to monitor assay performance.
    1. The Process Control should be used during sample preparation and amplification in the assay. This control should be added to each sample aliquot prior to PCR.
    1. Commercially available external positive HSV-1, HSV-2, and VZV controls may be treated as a patient specimen and should be used in accordance with your lab standards. Previously characterized positive HSV-1, HSV-2, and VZV specimens may be used in lieu of commercial HSV-1, HSV-2, and VZV controls.
    1. Viral transport media or previously characterized negative specimen may be used as an external negative control. This must be treated as a patient specimen and should be performed in accordance with current lab standards.
    1. Software:

FDA has reviewed applicant's Hazard Analysis and Software Development processes for this line of product types:

Yes___X______ or No___________________________________________________________________________________________________________________________________________________________

O. Other Supportive Instrument Performance Characteristics Data Not Covered In the "Performance Characteristics" Section above:

Not Applicable

P. Proposed Labeling:

The labeling is sufficient and satisfies the requirements of 21 CFR Part 809.10, 21 CFR 801.109, and the special controls.

O. Identified Potential Risks and Required Mitigation Measures

Identified Potential RisksRequired Mitigation Measures

36

Risk of false resultsSpecial controls (1), (2), and (3)
Failure to correctly interpret test resultsSpecial controls (4) and (5)
Failure to correctly operate the
instrumentSpecial controls (6) and (7)

R. Benefit/Risk Analysis

Summary
Summary of
the Benefit(s)When used for the proposed intended use, the benefits to the clinician and the patient
include: (1) establishment of the device performance in a manner that demonstrates
consistent accurate test results; and 2) ability to use a well validated device to diagnose
HSV 1, HSV 2 and VZV in cutaneous and mucocutaneous lesion swab specimens,
which will allow prompt initiation of disease specific treatment when that is indicated.
Summary of
the Risk(s)The risks associated with the device, when used as intended, are those related to the
risk of false test results, failure to correctly interpret the test results and failure to
correctly operate the instrument. Inaccurate test results may lead to error or delay in
the diagnosis of HSV 1, HSV 2 and VZV infections, error or delay in appropriate
treatment of these infections, failure or delay in implementing infection control
measures, unnecessary use of anti-viral therapy, and delay in establishing the patient's
true diagnosis.
Summary of
Other
FactorsHSV 1, HSV 2 and VZV infections may present as acute clinical episodes that are
likely to recur. In most patients these infections are mild, but in certain populations
they can be severe and life threatening. Severe infections are treated with antiviral
drugs such as acyclovir, but initiation of therapy in the first few days of the infection is
critical for a successful outcome.
The analytical studies conducted by the sponsor were robust while the clinical study
was limited by the number of VZV positive mucocutaneous lesion specimens available
to evaluate the device. The data provided is adequate to demonstrate the device's
performance characteristics. No post-market information is available.

37

| Conclusions | The probable benefits of this device outweigh the probable risks associated with its
use. There are no substantial clinical concerns with the classification of this device in
Class II given the combination of general and special controls. |
|-------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Do the
probable
benefits
outweigh the
probable risks? | |

S. Conclusion:

The information provided in this de novo submission is sufficient to classify this device into class II under regulation 21 CFR 866.3309 with special controls. FDA believes that special controls, along with the applicable general controls, provide reasonable assurance of the safety and effectiveness of the device type. The device is classified under the following:

| Device Type: | Herpes virus nucleic acid-based cutaneous and mucocutaneous lesion
panel |
|--------------|-----------------------------------------------------------------------------|
| Class: | II (special controls) |
| Regulation: | 21 CFR 866.3309 |

(a) Identification. A herpes virus nucleic acid- based cutaneous and mucocutaneous panel is a qualitative in vitro diagnostic device intended for the simultaneous detection and differentiation of different herpes viruses in cutaneous and mucocutaneous lesion samples from symptomatic patients suspected of Herpetic infections. Negative results do not preclude infection and should not be used as the sole basis for treatment or other patient management decisions. The assay is not intended for use in cerebrospinal fluid samples.

(b) Classification. Class II (special controls). The special controls for this device are:

    1. Premarket notification submissions must include detailed documentation for the device description, including the device components, ancillary reagents required but not provided, and a detailed explanation of the methodology including primer design and selection.
    1. Premarket notification submissions must include detailed documentation from the following analytical and clinical performance studies: Analytical sensitivity (Limit of Detection), reactivity, inclusivity, precision, reproducibility, interference, cross reactivity, carry-over, and cross contamination.
    1. Premarket notification submissions must include detailed documentation of a clinical study using lesion samples in which Herpes Simplex Virus 1, Herpes Simplex Virus 2, or Varicella Zoster Virus DNA detection was requested. The study must compare the device performance to an appropriate well established reference method.

38

    1. A detailed explanation of the interpretation of results and acceptance criteria must be included in the device's 21 CFR 809.10(b)(9) compliant labeling.
    1. The device labeling must include a limitation statement that reads: "The device is not intended for use with cerebrospinal fluid or to aid in the diagnosis of HSV or VZV infections of the central nervous system (CNS)."
    1. Premarket notification submissions must include quality assurance protocols and a detailed documentation for device software, including, but not limited to, standalone software applications and hardware-based devices that incorporate software.
    1. The risk management activities performed as part of the manufacturer's 21 CFR 820.30 design controls must document an appropriate end user device training program that will be offered as part of efforts to mitigate the risk of failure to correctly operate the instrument.