(81 days)
The IsoAmp® HSV Assay is an in vitro diagnostic test for the direct, qualitative detection of herpes simplex virus (HSV-1 & HSV-2) DNA in male and female genital and oral lesions. The test is intended for use as an aid in diagnosis of HSV infection in symptomatic patients.
Warning: The IsoAmp® HSV Assay is not FDA cleared for use with cerebrospinal fluid (CSF). The assay does not provide specific typing information to differentiate HSV-1 and HSV-2. The assay is not intended to be used for prenatal screening.
The IsoAmp® HSV Assay consists of three major steps: 1) specimen preparation: 2) isothermal Helicase-Dependent Amplification (HDA) of the HSV glycoprotein B (gB) gene using biotinylated primers; and 3) detection of the amplified DNA by a target-specific hybridization probe via a colorimetric reaction on a lateral-flow strip which is embedded in a self-contained disposable cassette to prevent amplicon contamination.
Specimen preparation includes a simple dilution step in which specimens in viral transport medium are diluted 40-fold in dilution buffer. The diluted samples are mixed with HDA reagents. Incubation at 64°C results in the release of the HSV DNA and subsequent isothermal amplification of the target sequence. A competitive internal control (IC) is included in the Amplification Reagents to monitor inhibitory substances in negative samples, reagent failure or device failure.
After incubation for one hour, the amplified DNA is detected by two detection probes, one labeled with fluorescein isothiocyanate (FITC) for hybridizing to the HSV target and the other labeled with digoxigenin (DIG) for binding to the IC target. The hybrid of FITC-labeled probe and HSV amplicon is captured at the Test Line (T-Line) on the lateral-flow strip by anti-FITC antibodies, while the DIG-labeled IC amplicon is captured at the Control Line (C-Line) on the strip by anti-DIG antibodies. The biotin label in each amplicon captures the streptavidinconjugated color particles for visualization and the test result is shown as colored lines that are visually read.
The self-contained Type II BESt™ cassettes contain lateral-flow DNA detection strips coated with anti-FITC antibodies and anti-DIG antibodies that serve as T line and C line respectively in the assay. A positive result (detection of HSV DNA) is reported when the T line is visible through the detection window of the cassette. A negative result (no detection of HSV DNA) is reported when only the C line is displayed. The assay result is regarded as invalid when both the T line and C line are not present and the assay should be repeated.
Here's a breakdown of the acceptance criteria and the study details for the IsoAmp® HSV Assay, based on the provided document:
1. Table of Acceptance Criteria and Reported Device Performance
| Feature/Metric | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Precision/Reproducibility | ||
| HSV-1 Low Positive | Not explicitly stated as an acceptance criterion, but implied to be high agreement for reliable detection near LoD. | Overall Percent Agreement: 99% (95% CI: 94% - 100%) |
| HSV-1 Moderate Positive | Not explicitly stated as an acceptance criterion, but implied to be 100% agreement for reliable detection. | Overall Percent Agreement: 100% (95% CI: 96% - 100%) |
| HSV-2 Low Positive | Not explicitly stated as an acceptance criterion, but implied to be high agreement for reliable detection near LoD. | Overall Percent Agreement: 96% (95% CI: 90% - 98%) |
| HSV-2 Moderate Positive | Not explicitly stated as an acceptance criterion, but implied to be 100% agreement for reliable detection. | Overall Percent Agreement: 100% (95% CI: 96% - 100%) |
| Negative Control | Not explicitly stated as an acceptance criterion, but implied to be 100% negative results for reliable non-detection. | Overall Percent Agreement: 99% (95% CI: 96% - 100%) |
| Limit of Detection (LoD) | ||
| HSV-1 LoD | >95% positivity rate at the lowest concentration level. | Determined at 1.1 x 10⁵ TCID₅₀/mL (Strain 2, 100% positivity with 95% CI: 88.65% - 100%). Strain 1 LoD was 3.7 x 10⁴ TCID₅₀/mL (97% positivity with 95% CI: 83.33% - 99.41%). The higher value was taken for HSV-1 LoD. |
| HSV-2 LoD | >95% positivity rate at the lowest concentration level. | Determined at 1.1 x 10⁴ TCID₅₀/mL (Strain 1, 100% positivity with 95% CI: 88.65% - 100%). Strain 2 LoD was 3.7 x 10³ TCID₅₀/mL (100% positivity with 95% CI: 88.30% - 100%). The higher value was taken for HSV-2 LoD. |
| Final Assay LoD | Defined as the higher of the HSV-1 and HSV-2 concentrations where 95% positivity was observed. | 1.1 x 10⁴ TCID₅₀/mL |
| Cross-Reactivity | No cross-reactivity observed with any panel member tested at clinically significant concentrations. | No cross-reactivity was observed with any of the 48 panel members tested. |
| Interfering Substances | ||
| Clinical Samples | No interference observed with the detection of HSV target or internal control. | No interference observed from 24 potentially interfering substances. |
| Viral Transport Media | No interference observed with the detection of HSV target or internal control. | No interference observed from Remel M4, M5, M4RT, Bartels VTM, and BD Universal Viral Transport. |
| Cross-Reactivity Panel | No interference observed with the detection of HSV target. | None of the cross-reactivity panel members interfered with HSV-1 and HSV-2 target detection when tested in presence of HSV. |
| Carry-Over/Cross Contamination | ||
| Negative samples | Negative results 100% of the time. | 10/10 negative samples tested were negative. |
| Positive samples | Positive results 100% of the time. | 10/10 positive samples tested were positive. |
| Clinical Performance (Genital Samples) | ||
| Sensitivity | Not explicitly stated as an acceptance criterion for a specific value, but implicit expectation for adequate diagnostic performance compared to the reference method for regulatory clearance. The predicate device's performance would likely serve as a benchmark for substantial equivalence. | 97.1% (264/272) with 95% Confidence Interval: 94.3 – 98.5% |
| Specificity | Not explicitly stated as an acceptance criterion for a specific value, but implicit expectation for adequate diagnostic performance compared to the reference method for regulatory clearance. The predicate device's performance would likely serve as a benchmark for substantial equivalence. | 93.4% (496/531) with 95% Confidence Interval: 91.0 – 95.2% |
| Clinical Performance (Oral Samples) | ||
| Sensitivity | Not explicitly stated as an acceptance criterion for a specific value, but implicit expectation for adequate diagnostic performance compared to the reference method for regulatory clearance. | 93.8% (45/48) with 95% Confidence Interval: 83.2 - 97.9% |
| Specificity | Not explicitly stated as an acceptance criterion for a specific value, but implicit expectation for adequate diagnostic performance compared to the reference method for regulatory clearance. | 87.4% (97/111) with 95% Confidence Interval: 79.9 - 92.3% |
| Retrospective Samples | ||
| Agreement with Reference | All retrospective samples positive by the reference method also shown positive by the IsoAmp® HSV Assay. (Implicit 100% agreement for this subset). | All 32 retrospective samples (15 genital, 17 oral) were positive by both IsoAmp® HSV Assay and the reference assay. |
2. Sample Size Used for the Test Set and Data Provenance
- Clinical Performance Test Set (Prospective and Retrospective combined): 994 swab samples.
- Prospective Samples: 962 samples (803 genital, 159 oral).
- Retrospective Samples: 32 samples (15 genital, 17 oral) tested at a single study site.
- Data Provenance:
- Country of Origin: United States.
- Retrospective or Prospective: A mix of both. The majority (962) were prospectively collected, and a smaller number (32) were retrospectively collected.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
- The document does not specify the number of experts or their qualifications for establishing the ground truth using the reference method (
Cell Culture based ELVIS® HSV ID/Typing Test System). The ELVIS system is a commercial diagnostic kit, and its results would be interpreted according to its own instructions, potentially by trained laboratory personnel rather than clinical "experts" in the sense of physicians or radiologists. - For the discordant samples, "bidirectional sequence analysis" was used to resolve discrepancies, but the personnel performing and interpreting this analysis are not described.
4. Adjudication Method for the Test Set
- The primary method for establishing ground truth was comparison to a "gold standard/reference method," the
Cell Culture based ELVIS® HSV ID/Typing Test System. - For discordant results between the IsoAmp® HSV Assay and the ELVIS system, bidirectional sequence analysis was used as an adjudication method.
- For genital samples: 35 samples discordant by the IsoAmp assay were tested by sequencing.
- For oral samples: 14 samples discordant by the IsoAmp assay were tested by sequencing.
- This suggests a process where sequencing served as a tie-breaker or a higher-fidelity reference for ambiguous cases.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No, an MRMC comparative effectiveness study was not done.
- This study evaluated a diagnostic assay (a lab test), not an AI algorithm assisting human readers in interpreting images or other complex data. Therefore, the concept of "how much human readers improve with AI vs. without AI assistance" does not apply here.
6. Standalone Performance (Algorithm Only Without Human-in-the-Loop Performance)
- Yes, a standalone performance was done. The entire study tests the performance of the IsoAmp® HSV Assay as a complete system, which operates independently to produce a result, with visual reading of the lateral flow strip. There isn't a human interpreting images or data that the algorithm generates and then making a judgment. The visual reading of the T-line and C-line on the lateral flow strip could be considered the "human-in-the-loop" component for result interpretation, but the core performance data (sensitivity, specificity, LoD, etc.) reflects the assay's output as an isolated system. The results presented are for the device's output itself.
7. Type of Ground Truth Used
- Reference Method: Cell Culture based ELVIS® HSV ID/Typing Test System. This is a recognized laboratory "gold standard" for HSV detection.
- Adjudication for Discordant Results: Bidirectional sequence analysis. This is a highly accurate molecular method used to confirm the presence and type of viral DNA.
8. Sample Size for the Training Set
- The document does not explicitly mention a distinct "training set" for the IsoAmp® HSV Assay. This is common for molecular diagnostic assays like this, which are developed through iterative R&D processes (optimizing reagents, protocols, etc.) rather than supervised machine learning where a specific "training set" is used to teach an algorithm.
- The analytical performance studies (LoD, cross-reactivity, interference) use spiked samples and cultured organisms, which contribute to the development and validation of the assay but are not typically referred to as a "training set" in the AI/ML sense.
9. How the Ground Truth for the Training Set Was Established
- As no explicit "training set" is described for an AI/ML context, this question is not directly applicable.
- For the analytical studies (e.g., LoD, cross-reactivity), the "ground truth" for the samples used was established by:
- Quantified cultures: For LoD studies, HSV strains were precisely quantified (TCID₅₀/mL).
- Known organisms/DNA: For cross-reactivity, purified DNA and cultured organisms of known identity and concentration were used.
- HSV-negative matrix pools: Used as negative controls and for diluting samples.
- These are standard methods in in vitro diagnostic assay development to create samples with a known status.
{0}------------------------------------------------
તાવિકા
1.0 Submitter
Date of Summary: September 24, 2011 SEP 2 7 2011
IsoAmp® HSV Assay Product Name: Sponsor: BioHelix Corporation 500 Cummings Center Suite 5550 Beverly, MA 01915
Correspondent : MDC Associates, LLC Fran White, Regulatory Consultant 180 Cabot Street Beverly, MA 01915
2.0 Device Identification
Trade or Proprietary Name: IsoAmp® HSV Assay Herpes simplex virus Assay Common or Usual Name: Product Code: oqo Regulation Section: 21 CFR 866.3305 Product Classification: Class II
3.0 Substantial Equivalency
IsoAmp® HSV Assay is substantially equivalent to the EraGen Biosciences MultiCode®-RTx Herpes Simplex Virus 1 & 2 Kit (K100336). The table below identifies the characteristics of BioHelix Corporation's IsoAmp® HSV Assay (K111951) and the EraGen Biosciences MultiCode®-RTx Herpes Simplex Virus 1 & 2 Kit (Predicate Device).
{1}------------------------------------------------
| Features | BioHelix CorporationIsoAmp® HSV Assay(New Device) | SIMILARITIES | EraGen BioscienceMulticode® RTx Herpes Simplex Virus 1 & 2 Kit(Predicate Device) | ||
|---|---|---|---|---|---|
| K111951 | K100336 | ||||
| Intended use | The IsoAmp® HSV Assay is an in vitro diagnostic test forthe direct, qualitative detection of herpes simplex virus(HSV-1 & HSV-2) DNA in male and female genital and orallesions. The test is intended for use as an aid in diagnosisof HSV infection in symptomatic patients.Warning: The IsoAmp® HSV Assay is not FDA cleared foruse with cerebrospinal fluid (CSF). The assay does notprovide specific typing information to differentiate HSV-1 and HSV-2. The assay is not intended to be used forprenatal screening. | The MultiCode®-RTx HSV-1&2 Kit is a polymerase chainreaction (PCR) -based qualitative in vitro diagnostic test forthe detection and typing of herpes simplex virus (HSV-1&2DNA in vaginal lesions. It is indicated for use in thedetection and typing of HSV-1 or HSV-2 in vaginal lesionswab specimens from symptomatic female patients as anaid in the diagnosis of genital herpes infection.Warning: The device is no FDA cleared for the use withcerebral spinal fluid (CSF) or any lesions other thanvaginal. This assay is not intended to be used for malepenile specimens, for prenatal screening, or for femalesunder the age of 18 years. | |||
| Assay Results | Qualitative | Qualitative | |||
| Analysis Software Provided | No | Yes | |||
| Printed Results Report Provided | No | No | |||
| Detection of HSV-1 and HSV-2 | Yes | Yes | |||
| DIFFERENCES | |||||
| Methodology | HDA (Helicase-Dependent Amplification) | Real-Time PCR | |||
| Typing of HSV-1 and HSV-2 | No | Yes | |||
| Packaging | The product is supplied as two (2) separate labeledboxes. | The product is supplied in labeled, sterile tubes. Theouter container is a labeled box. | |||
| Kit Reagent Storage Conditions | AKRC: ≤-15°CNKC: 15-30°C | -15°C to -30°C |
Comparison of New Device with Predicate Device
{2}------------------------------------------------
4.0 Product Description
The IsoAmp® HSV Assay consists of three major steps: 1) specimen preparation: 2) isothermal Helicase-Dependent Amplification (HDA) of the HSV glycoprotein B (gB) gene using biotinylated primers; and 3) detection of the amplified DNA by a target-specific hybridization probe via a colorimetric reaction on a lateral-flow strip which is embedded in a self-contained disposable cassette to prevent amplicon contamination.
Specimen preparation includes a simple dilution step in which specimens in viral transport medium are diluted 40-fold in dilution buffer. The diluted samples are mixed with HDA reagents. Incubation at 64°C results in the release of the HSV DNA and subsequent isothermal amplification of the target sequence. A competitive internal control (IC) is included in the Amplification Reagents to monitor inhibitory substances in negative samples, reagent failure or device failure.
After incubation for one hour, the amplified DNA is detected by two detection probes, one labeled with fluorescein isothiocyanate (FITC) for hybridizing to the HSV target and the other labeled with digoxigenin (DIG) for binding to the IC target. The hybrid of FITC-labeled probe and HSV amplicon is captured at the Test Line (T-Line) on the lateral-flow strip by anti-FITC antibodies, while the DIG-labeled IC amplicon is captured at the Control Line (C-Line) on the strip by anti-DIG antibodies. The biotin label in each amplicon captures the streptavidinconjugated color particles for visualization and the test result is shown as colored lines that are visually read.
The self-contained Type II BESt™ cassettes contain lateral-flow DNA detection strips coated with anti-FITC antibodies and anti-DIG antibodies that serve as T line and C line respectively in the assay. A positive result (detection of HSV DNA) is reported when the T line is visible through the detection window of the cassette. A negative result (no detection of HSV DNA) is reported when only the C line is displayed. The assay result is regarded as invalid when both the T line and C line are not present and the assay should be repeated.
5.0 Indications for Use and Intended Use
The IsoAmp® HSV Assay is an in vitro diagnostic test for the direct, qualitative detection of herpes simplex virus (HSV-1 & HSV-2) DNA in male and female genital and oral lesions. The test is intended for use as an aid in diagnosis of HSV infection in symptomatic patients.
Warning: The IsoAmp® HSV Assay is not FDA cleared for use with cerebrospinal fluid (CSF). The assay does not provide specific typing information to differentiate HSV-1 and HSV-2. The assay is not intended to be used for prenatal screening.
6.0 Analytical Performance
l.
:
- Precision/Reproducibility:
The Precision/Reproducibility of the IsoAmp® HSV Assay was evaluated at three (3) test sites. A panel of seven (7) members was prepared containing one negative control sample (HSV negative pooled swab specimens) and six simulated HSV-1 and HSV-2 samples that included High Negative (below the assay limit of detection), Low Positive (near the assay limit of detection) and Moderate Positive (three times the assay limit of detection) samples. The panel (which included one replicate of each panel member), along with external HSV-1 and HSV-2 positive and negative controls, was tested at each site for five (5) days
{3}------------------------------------------------
by two operators with each operator running the panel two times a day using a single lot of the IsoAmp® HSV Assay. One (1) site tested the panel using three (3) lots. Results of the Precision/Reproducibility study for the IsoAmp® HSV at three sites are presented in the table below.
| Overall Reproducibility Study | |||||
|---|---|---|---|---|---|
| Category | Site #1* | Site #2 | Site #3 | Overall Percent Agreement | 95% Confidence Interval |
| Percent Agreement | Percent Agreement | Percent Agreement | |||
| HSV-1 High Negative | 13/6022% | 13/2065% | 6/2030% | 32/10032% | 24% - 42% |
| HSV-1 Low Positive | 60/60100% | 19/2095% | 20/20100% | 99/10099% | 94% - 100% |
| HSV-1 Moderate Positive | 60/60100% | 20/20100% | 20/20100% | 100/100100% | 96% - 100% |
| HSV-2 High Negative | 19/6032% | 7/2035% | 6/2030% | 32/10032% | 24% - 42% |
| HSV-2 Low Positive | 60/60100% | 18/2090% | 18/2089% | 96/10096% | 90% - 98% |
| HSV-2 Moderate Positive | 60/60100% | 20/20100% | 20/20100% | 100/100100% | 96% - 100% |
| Negative1 | 60/60100% | 20/20100% | 19/2095% | 99/10099% | 96% - 100% |
| HSV-1 Positive Control | 60/60100% | 20/20100% | 20/20100% | 100/100100% | 96% - 100% |
| HSV-2 Positive Control | 60/60100% | 20/20100% | 20/20100% | 100/100100% | 96% - 100% |
| Assay Negative Control2 | 60/60100% | 20/20100% | 20/20100% | 100/100100% | 96% - 100% |
| *Site#1 tested two additional lots |
Overall Reproducibility Study
II. Linearity/Assay Reportable Range: Not Applicable
III. Level of Detection (LoD)
A Limit of Detection (LoD) study was performed to determine the analytical sensitivity of the IsoAmp HSV Assay using two representative strains of HSV-1 and two representative strains of HSV-2. Quantified (TCID50/mL) cultures of the HSV-1 and HSV-2 strains were serially diluted to five (5) concentrations in HSVnegative matrix pools and tested in replicates of ten (10) on three (3)
Negative pooled serum control
2 Remel M4 transport media
{4}------------------------------------------------
reagent lots. The observed LoD of a HSV strain was determined as the lowest concentration level that had a positivity rate of >95%. Since two (2) representative strains of HSV-1 and HSV-2 were used in the study, the higher LoD value was defined as the observed LoD for HSV-1 and HSV-2 respectively. Since the IsoAmp® HSV Assay does not differentiate viral types, the final assay LoD is defined as the higher of the HSV-1 and HSV-2 concentrations where 95% positivity was observed.
In addition, LoD confirmation studies were conducted to confirm the observed LoD for HSV-1 and HSV-2. The first confirmatory study included testing the four (4) representative HSV-1 and HSV-2 strains 20 times each at the corresponding observed LoD. Each strain was tested by three (3) reagent lots, and all four strains showed a positivity rate of 100%. In addition, twenty (20) HSV-1 and 20 HSV-2 clinical isolates were cultured and quantified in TCIDso/mL. Each isolate was diluted to the corresponding LoD in HSV-negative matrix and tested in triplicate. IsoAmp® HSV Assay was able to detect all 20 HSV-1 and 20 HSV-2 clinical isolates.
- a. HSV-1
The LoD for HSV-1 Strain 1 was determined to be 3.7 x 10° TCIDso/mL. At this concentration, 97% of samples were detected with a 95% Confidence Interval of 83.33% - 99.41%. The LoD for HSV-1 Strain 2 was determined to be 1.1 x 105 TCID50/mL. At this concentration, 100% of samples were detected with a 95% Confidence Interval of 88.65% - 100%. Therefore, the LoD for HSV-1 is 1.1 x 10° TCID50/mL.
| Strain 1(TCID50/mL) | Positive/Total | Positivity Rate | 95% CI | |
|---|---|---|---|---|
| 3.3 x 105 | 30/30 | 100% | 88.65% | 100.00% |
| 1.1 x 105 | 30/30 | 100% | 88.65% | 100.00% |
| 3.7 x 104 | 29/30 | 97% | 83.33% | 99.41% |
| 1.2 x 104 | 18/30 | 60% | 42.32% | 75.41% |
| 4.1 x 103 | 10/30 | 33% | 19.23% | 51.22% |
| Strain 2(TCID50/mL) | Positive/Total | Positivity Rate | 95% CI | |
| 3.3 x 105 | 30/30 | 100% | 88.65% | 100.00% |
| 1.1 x 105 | 30/30 | 100% | 88.65% | 100.00% |
| 3.7 x 104 | 28/30 | 93% | 78.68% | 98.15% |
| 1.2 x 104 | 19/30 | 63% | 45.51% | 78.13% |
| 4.1 x 103 | 9/30 | 30% | 16.66% | 47.88% |
b. HSV-2
The LoD for HSV-2 Strain 1 was determined to be 1.1 x 10° TCID50/mL. At this concentration, 100% of samples were detected with a 95% Confidence Interval of 88.65% - 100%. The LoD for HSV-2 Strain 2 was
{5}------------------------------------------------
determined to be 3.7 x 103 TCID50/mL. At this concentration, 100% of samples were detected with a 95% Confidence Interval of 88.30% – 100%. Therefore, the LoD for HSV-2 is 1.1 x 104 TCIDso/mL.
| Strain 1(TCID50/mL) | Positive/Total | Positivity Rate | 95% CI | |
|---|---|---|---|---|
| 3.3 x 104 | 30/30 | 100% | 88.65% | 100.00% |
| 1.1 x 104 | 30/30 | 100% | 88.65% | 100.00% |
| 3.7 x 103 | 26/30 | 87% | 70.32% | 94.69% |
| 1.2 x 103 | 14/30 | 47% | 30.23% | 63.86% |
| 4.1 x 103 | 8/30 | 27% | 14.18% | 44.45% |
| Strain 2(TCID50/mL) | Positive/Total | Positivity Rate | 95% CI | |
| 3.3 x 104 | 30/30 | 100% | 88.65% | 100.00% |
| 1.1 x 104 | 30/30 | 100% | 88.65% | 100.00% |
| 3.7 x 103 | 29/29 | 100% | 88.30% | 100.00% |
| 1.2 x 103 | 25/30 | 83% | 66.44% | 92.66% |
| 4.1 x 102 | 8/30 | 27% | 14.18% | 44.45% |
Assay LoD C.
Since the IsoAmp® HSV Assay does not differentiate viral types, the final assay LoD is defined as the higher of the HSV-1 and HSV-2 concentrations where 95% positivity was observed. The final assay LoD claim is 1.1 x 10-TCID50/mL.
IV. Cross Reactivity Testing (Analytical Specificity)
A cross-reactivity study was performed to determine if any organisms which may present with the same clinical symptoms as HSV, which are associated with bacterial vaginosis or which are commonly found in the genital track and oral area could give positive results with the IsoAmp® HSV Assay. Forty-eight (48) specificity panel members including purified DNA and cultured organisms were tested with the IsoAmp® HSV assay in triplicate following instructions in the Package Insert. No cross-reactivity was observed with any panel member tested at clinically significant concentrations.
| Organisms | Member Type (GD1,QC2, IHC3) | Test Concentration |
|---|---|---|
| Acinetobacter calcoaceticus var. anitratus (ATCC 51432) | IHC | $1.0 x 10^6$ CFU/mL |
| Acinetobacter lwoffi (ATCC 17925) | IHC | $1.0 x 10^7$ CFU/mL |
| Adenovirus 2 | QC | $1.0 x 10^6$ TCID50/mL |
| Bacteroides fragilis | QC | $1.0 x 10^7$ CFU/mL |
| Candida albicans (ATCC 14053) | IHC | $1.0 x 10^7$ CFU/mL |
| Organisms | Member Type (GD1,QC2, IHC3) | Test Concentration |
| Candida glabrata | QC | 1.0 x 107 CFU/mL |
| Candida guilliermondii | QC | 1.0 x 107 CFU/mL |
| Candida krusei | QC | 1.0 x 106 CFU/mL |
| Candida lusitaniae | QC | 1.0 x 107 CFU/mL |
| Candida parapsilosis | QC | 1.0 x 107 CFU/mL |
| Candida tropicalis | QC | 1.0 x 107 CFU/mL |
| Chlamydia trachomatis LGV-I1434 | GD | 1.0 x 107 cp/mL |
| Cytomegalovirus | QC | 1.0 x 106 TCID50/mL |
| Enterobacter cloacae (ATCC 13047) | IHC | 1.0 x 107 CFU/mL |
| Enterovirus (Type 71) | QC | 1.0 x 105 TCID50/mL |
| Epstein-Barr Virus | GD | 1.0 x 106 cp/mL |
| Escherichia coli (ATCC 25922) | IHC | 1.0 x 107 CFU/mL |
| Fusobacterium nucleatum (ATCC 25586) | IHC | 1.0 x 107 CFU/mL |
| Gardnerella vaginalis (ATCC 14018) | IHC | 1.0 x 107 CFU/mL |
| Haemophilus ducreyi | QC | 8.5 x 105 CFU/mL |
| Human Herpes 6 virus (Z29 strain) | QC | 1.0 x 106 TCID50/mL |
| Human Herpes 7 virus (SB strain) | QC | 1.0 x 106TCID50/mL |
| Human papilloma virus 16 (HPV16) | GD | 1.0 x 108 cp/mL |
| Human papilloma virus 18 (HPV18) | GD | 1.0 x 105 cp/mL |
| Klebsiella pneumoniae | QC | 1.0 x 107 CFU/mL |
| Lactobacillus acidophilus Z048 | QC | 1.0 x 107 CFU/mL |
| Mobiluncus curtisii V125 [DSM 2711] | QC | 1.0 x 107 CFU/mL |
| Mobiluncus mulieris BV 64-5 | QC | 1.0 x 106 CFU/mL |
| Moraxella catarrhalis | QC | 1.0 x 107 CFU/mL |
| Mycoplasma hominis (ATCC 23114) | IHC | 1.0 x 107 CFU/mL |
| Neisseria gonorrhoeae (ATCC 21823) | IHC | 1.0 x 107 CFU/mL |
| Neisseria meningitides | QC | 1.0 x 107 CFU/mL |
| Prevotella melaninogenica | QC | 1.0 x 107 CFU/mL |
| Rubella virus | QC | 4.17 x 105 TCID50/mL |
| Simian Virus type 40 (SV40) | QC | 1.0 x 106 TCID50/mL |
| Staphylococcus aureus MRSA (ATCC 33591) | IHC | 1.0 x 107 CFU/mL |
| Staphylococcus aureus MSSA (ATCC 25923) | IHC | 1.0 x 107 CFU/mL |
| Staphylococcus epidermidis MRSE (ATCC700566) | IHC | 1.0 x 107 CFU/mL |
| Staphylococcus saprophyticus MRSE (ATCC 15305) | IHC | 1.0 x 107 CFU/mL |
| Streptococcus mitis clinical isolate | QC | 1.0 x 107 CFU/mL |
| Streptococcus mutans Z072 | QC | 1.0 x 106CFU/mL |
| Organisms | Member Type (GD1,QC2, IHC3) | Test Concentration |
| Streptococcus pneumoniae | QC | 1.0 x 107 CFU/mL |
| Streptococcus pyogenes: (ATCC19615) | IHC | 1.0 x 107 CFU/mL |
| Streptococcus salivarius (ATCC BAA-1024) | IHC | 1.0 x 107 CFU/mL |
| Toxoplasma gondii | QC | 6.6 x 106 CFU/mL |
| Treponema pallidum | QC | 1.0 x 107 TP/mL |
| Trichomonas vaginalis | QC | 1.0 x 106 CFU/mL |
| Varicella-Zoster Virus (VZV) | GD | 1.0 x 106 cp/mL |
Genomic DNA
2 Quantified Cultures
3 In-House Culture
{6}------------------------------------------------
·
.
{7}------------------------------------------------
V. Interfering Substances
Potentially interfering substances i.e. viral transport media, substances that might be present in clinical samples, and organisms/cross reactive panel members listed under cross reactivity were tested to confirm that they did not interfere with the performance of the IsoAmp® HSV Assay.
All interference testing was carried out in the presence of HSV-1 and HSV-2 at three times the observed LoD (3 x LoD). All test runs were conducted in triplicate. Controls were tested with each run.
a. Interfering Substances
Performance of the IsoAmp® HSV Assay was characterized in the presence of twenty-four (24) potentially interfering substances which could reasonably be expected to be present in genital and oral swab specimens. Interfering substances were tested at the highest ("worst case") concentration expected in clinical samples. The panel was also tested in triplicate in the absence of HSV to see if the potentially interfering substances interfere with the detection of the internal control. No interference was observed in the presence of the potential interfering substances tested.
| Substances (active ingredients) | Calculated Concentration |
|---|---|
| Whole blood with EDTA | 7% (v/v) |
| Female Urine | 7% (v/v) |
| Male Urine | 7% (v/v) |
| Acyclovir (Acycloguanosine) 10% | 7 mg/mL |
| Albumin | 3.3 mg/mL |
| Casein | 7 mg/mL |
| K-Y Brand Jelly | 7% (w/v) |
| Douche (Decyl Glucoside; Octoxynol-9) | 7% (v/v) |
| Contraceptive Jelly | 7% (w/v) |
| YeastGard (Phosphoricum Acidum 4X) | 7% (w/v) |
| Monistat 1 (Miconazole Nitrate cream (2%)) | 7% (w/v) |
| Vagisil Crème (Benzocaine (20%), Resorcinol (3%)) | 7% (w/v) |
| Monistat 3 (Miconazole Nitrate Cream (4%)) | 7% (w/v) |
{8}------------------------------------------------
| Triconazole 1 (Tioconazole (300 mg) (6.5%)) | 7% (w/v) |
|---|---|
| Balneol Hygienic Cleansing Lotion | 7% (w/v) |
| Clotrimazole 3 Vaginal Cream (Clotrimazole 100 mg (2%)) | 7% (w/v) |
| CVS Anti-Itch Cream (Benzocaine 5%; Benzalkonium Chloride 0.13%) | 7% (w/v) |
| Listerine Antiseptic Mouth Wash | 7% (v/v) |
| Abreva (Docosanol 10%) | 7% (w/v) |
| Carmex Cold Sore Lip Balm (Menthol (0.7%), Camphor (1.7%), Phenol (0.4%)) | 7% (w/v) |
| Releev cold sore treatment (Benzalkonium Chloride (0.13%)) | 7% (w/v) |
| Lip clear Lysine+ (Zinc Oxide (1.2%)) | 7% (w/v) |
| Toothpaste | 7% (w/v) |
| Buffy coat | 7% (v/v) |
b. Viral Transport Media
The performance of the IsoAmp® HSV Assay was assessed with Remel M4, Remel M5, Remel M4RT, Bartels VTM, and BD Universal Viral Transport (UVT). Each medium was tested after spiking with HSV-1 and HSV-2 strain to a final concentration of approximately 3 x LoD to determine if the viral transport media interferes with the detection of HSV targets in positive samples. The media were tested in the absence of HSV-1 and HSV-2 (medium only) to see if the viral transport media interferes with the detection of the internal control in negative samples. There was no interference observed with the Remel M4, Remel M4RT, Remel M5, Bartels VTM, and BD UVT media for the detection of HSV-1 and HSV- 2 target or the internal control. M4, M4RT, M5, Bartels VTM, and BD UVT did not interfere with the detection of HSV-1 and HSV-target or the internal control.
Cross-Reactivity Panel Members C.
The performance of the IsoAmp® HSV Assay was characterized by testing the organisms that were evaluated for analytical specificity and cross reactivity in the presence of HSV-1 and HSV-2 strains at 3xLoD separately to see if the presence of these organisms interferes with the detection of HSV target. Each panel member was tested in triplicate. None of the cross reactivity panel members interfered with the detection of HSV-1 and HSV-2 target.
VI. Carry-Over and Cross Contamination
Carry-over/Cross Contamination Study was done only with HSV-1 target since both HSV-1 and HSV-2 share a single set of primers and probes for target amplification and detection. The HSV-1 Strain 1 was used directly without dilution. Viral transport media was used as the negative sample. Ten (10) replicates of negative sample together with assay controls were run by two (2) operators to confirm that negative samples generate a negative result 100% of the time. Five (5) replicates of high-concentration positive and negative samples were tested in a series, alternating sample types. All results were
{9}------------------------------------------------
as expected. Negative samples tested were negative (10/10) and positive samples were positive (10/10).
- VII. Assay Cut-Off: Not Applicable
Clinical Performance 7.0
The performance of the IsoAmp® HSV Assay was evaluated at five geographically diverse locations within the United States from 2010 - 2011. A total of nine hundred and ninetyfour (994) swab samples obtained from male and female genital and oral lesions were collected in Viral Transport Media (Remel M4, Remel M4RT, BD Universal Viral Transport and Bartels VTM) from the patient population ranging from <1 year to 92 years, and evaluated. Of the 994 specimens, 962 prospective samples and 32 retrospective samples were tested. Of the 962 prospective samples, 803 genital samples and 159 oral samples were tested. Of the 32 retrospective samples, 15 genital and 17 oral samples were tested at a single study site. Genital swab specimens were collected from vaginal, labial, penile and rectal lesions. Oral swab specimens were collected from lips, gums, and mouth.
The performance of the IsoAmp HSV Assay was compared with a gold standard/reference method i.e., Cell Culture based ELVIS® HSV ID/Typing Test System using an enzyme linked virus inducible system.
| Reference Method | ||||
|---|---|---|---|---|
| POS | NEG | Total | ||
| IsoAmp° HSV Assay | POS | 264 | 351 | 299 |
| NEG | 82 | 496 | 504 | |
| Total | 272 | 531 | 803 | |
| Value | 95% Confidence Interval | |||
| Sensitivity | 97.1% (264/272) | 94.3 – 98.5% | ||
| Specificity | 93.4% (496/531) | 91.0 – 95.2% |
1. Prospective Sample Data
- Genital Samples Only a.
* 35 samples were tested using bidirectional sequence analysis detected HSV target in 29 (6 HSV-1, 23 HSV-2) of the 35 discordant samples identified as HSV Positive by the Issay. Sequence analysis did not detect HSV in six (6) of the discordant samples.
² Eight (8) samples were tested using bidirectional sequence analysis did not detect HSV target in four (4) of the 8 samples identified as HSV Negative by the IsoAmp® HSV Assay. Sequence analysis did detect HSV in four (4) samples (2 HSV-2)
{10}------------------------------------------------
b. Oral Samples Only
| Reference Method | ||||
|---|---|---|---|---|
| POS | NEG | Total | ||
| IsoAmp HSV Assay | POS | 45 | 14¹ | 59 |
| NEG | 3² | 97 | 100 | |
| Total | 48 | 111 | 159 | |
| Value | 95% Confidence Interval | |||
| Sensitivity | 93.8% (45/48) | 83.2 - 97.9% | ||
| Specificity | 87.4% (97/111) | 79.9 - 92.3% |
Retrospective Sample Data II.
All of the 32 retrospective samples, 15 genital and 17 oral samples were shown positive by both the IsoAmp HSV Assay and the reference assay.
8.0 Statement of Supporting Data
The results of the analytical and clinical performance studies submitted in this premarket notification are complete and demonstrate that the IsoAmp® HSV Assay is substantially equivalent to the predicate device.
ี 14 samples were tested using bidirectional sequence analysis detected HSV target in 13 [12 HSV-2] of the 14 discordant samples identified as HSV Positive by the IsoAmp® HSV Assay. Sequence analysis did not detect HSV in one (1) of the discordant samples.
7 Three (3) samples were tested using bidirectional sequence analysis did not detect HSV target in two (2) of the 3 samples identified as HSV Negative by the IsoAmp® HSV Assay. Sequence analysis did detect HSV in one (1) samples (1 HSV-1)
{11}------------------------------------------------
Image /page/11/Picture/1 description: The image shows the logo for the U.S. Department of Health and Human Services. The logo consists of a circular border with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the circumference. Inside the circle is an abstract symbol resembling a stylized human figure with outstretched arms, possibly representing care or protection.
Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993
BioHelix Corporation c/o Fran White Regulatory Consultant 500 Cummings Center Suite 5550 Beverly, MA 01915
27 230
Re: K111951
Trade/Device Name: IsoAmp® HSV Assay Regulation Number: 21 CFR $866.3305 Herpes Simplex Virus Nucleic Acid Amplification Assay Regulation Name: Regulatory Class: Class II Product Code: 000 Dated: July 6, 2011 Received: July 8, 2011
Dear Ms. White:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. 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.
If your device is classified (see above) into class II (Special Controls), it may be subject to such additional controls. Existing major regulations affecting your device can be found in Title 21, Code of Federal Regulations (CFR), Parts 800 to 895. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); and good manufacturing practice
{12}------------------------------------------------
requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820). This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Parts 801 and 809), please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (301) 796-5450. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH 's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.
You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html.
Sincerely yours,
Wine Salt for
Sally A. Hojvat, M.Sc., Ph.D. Director Division of Microbiology Devices Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health
Enclosure
{13}------------------------------------------------
Indications for Use
510(k) Number (if known): K11951
lsoAmp® HSV Assay Device Name:
Indications for Use:
The IsoAmp® HSV Assay is an in vitro diagnostic test for the direct, qualitative detection of herpes simplex virus (HSV-1 & HSV-2) DNA in male and female genital and oral lesions. The test is intended for use as an aid in diagnosis of HSV infection in symptomatic patients.
Warning: The IsoAmp® HSV Assay is not FDA cleared for use with cerebrospinal fluid (CSF). The assay does not provide specific typing information to differentiate HSV-1 and HSV-2. The assay is not intended to be used for prenatal screening.
Prescription Use _____________________________________________________________________________________________________________________________________________________________ × (Part 21 CFR 801 Subpart D)
AND/OR
Over-The-Counter Use (21 CFR 801 Subpart C)
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)
Concurrence of CDRH, Office of In Vitro Diagnostic Device Evaluation and Safety (OIVD)
Tiawad, Feldsly
Division Sign-Off Office of In Vitro Diagnostic Device Evaluation and Safety
510(k) 111951
Page 1 of 1
§ 866.3305 Herpes simplex virus serological assays.
(a)
Identification. Herpes simplex virus serological assays are devices that consist of antigens and antisera used in various serological tests to identify antibodies to herpes simplex virus in serum. Additionally, some of the assays consist of herpes simplex virus antisera conjugated with a fluorescent dye (immunofluorescent assays) used to identify herpes simplex virus directly from clinical specimens or tissue culture isolates derived from clinical specimens. The identification aids in the diagnosis of diseases caused by herpes simplex viruses and provides epidemiological information on these diseases. Herpes simplex viral infections range from common and mild lesions of the skin and mucous membranes to a severe form of encephalitis (inflammation of the brain). Neonatal herpes virus infections range from a mild infection to a severe generalized disease with a fatal outcome.(b)
Classification. Class II (special controls). The device is classified as class II (special controls). The special control for the device is FDA's revised guidance document entitled “Class II Special Controls Guidance Document: Herpes Simplex Virus Types 1 and 2 Serological Assays.” For availability of the guidance revised document, see § 866.1(e).