PORTRAIT ANALYZER

{0}------------------------------------------------ ## EVALUATION OF AUTOMATIC CLASS III DESIGNATION (DE NOVO) FOR PORTRAIT TOXIGENIC C. DIFFICILE ASSAY ### REGULATORY INFORMATION FDA identifies this generic type of device as: A Clostridium difficile toxin gene amplification assay is a device that consists of reagents for the amplification and detection of target sequences in Clostridium difficile toxin genes in fecal specimens from patients suspected of having Clostridium difficile infection (CDI). The detection of clostridial toxin genes, in conjunction with other laboratory tests, aids in the clinical laboratory diagnosis of CDI caused by Clostridium difficile. NEW REGULATION NUMBER: 21 CFR 866.3130 CLASSIFICATION: II PRODUCT CODE: OZN ## BACKGROUND DEVICE NAME: PORTRAIT TOXIGENIC C. DIFFICILE ASSAY 510(K): K113358 DATE OF 510(K) NSE DECISION: FEBRUARY 3, 2012 DATE OF DE NOVO PETITION: MARCH 2, 2012 PETITIONER CONTACT: GREAT BASIN SCIENTIFIC, INC. – MR LARRY REA PETITIONER'S RECOMMENDED CLASSIFICATION: II ## PETITIONER'S RECOMMENDED CONTROLS: - · Class II Special Controls Guidance Document: Toxin Gene Amplification Assays for the detection of Clostridium difficile. - · General controls ## INDICATIONS FOR USE Portrait Toxigenic C. difficile Assay, a prescription device under 21 CFR Part 801.109 that is indicated for the detection of toxigenic Clostridium difficile in human fecal samples collected from patients suspected of having Clostridium difficile infection (CDI). The test utilizes automated blocked primer enabled helicase-dependent amplification (bpHDA) to detect toxin gene sequences associated with toxin producing C. difficile. The Portrait Toxigenic C. difficile Assay is intended as an aid in the diagnosis of CDI. # LIMITATIONS For prescription use only {1}------------------------------------------------ ## PLEASE REFER TO THE LABELING FOR A MORE COMPLETE LIST OF WARNINGS, PRECAUTIONS AND CONTRAINDICATIONS. ## DEVICE DESCRIPTION The Portrait Toxigenic C. difficile Assay as run on the Portrait Analyzer is a bench top fully automated in vitro diagnostics system that includes the Portrait Analyzer, control Laptop PC and single-use Portrait Toxigenic C. difficile Test Cartridges and sample preparation apparatus. The Portrait Analyzer is designed to perform automated sample extraction; blocked primer mediated thermophilic helicasedependent amplification (bpHDA); and chip-based detection with integrated data analysis in approximately 85 minutes. The sample to be tested is inserted into the sample preparation that has been preloaded with buffer and briefly vortexed. The vortexed mixture is then loaded into the assay cartridge. The cartridge is loaded into the Portrait Analyzer which performs extraction (cell lysing), amplification, hybridization and signal formation on the detection chip. The resulting signal(s) are detected and interpreted by the automated Portrait Analyzer. In addition to the necessary probes and primers to detect the presence of tcdB (toxin B gene) performance of the Portrait Toxigenic C. difficile Assay includes an integrated SPC to insure the adequate processing of the sample during preparation and subsequent extraction and amplification steps. ## SUMMARY OF NONCLINICAL/BENCH STUDIES - a. The limit of detection (LoD) of the Portrait toxigenic C. difficile Assay for C. difficile was assessed and confirmed by using strains of two different toxinotypes: ATCC strain 43255 (CCUG 19126, VPI 10463), toxinotype 0 A+B+ and ATCC strain 43598 (1470), toxinotype VIII A-B+. The following Table shows performance of the Portrait Toxigenic C. difficile assay on serial dilutions of two C. difficile strains for initial sensitivity study (CFU/test). | <i>C. difficile</i> strains | Toxinotype | Tested Serial<br>Dilutions<br>(CFU/test) | <i>'C. difficile</i><br>detected | |------------------------------------|----------------|------------------------------------------|----------------------------------| | ATCC 43255 (CCUG 19126, VPI 10463) | Type 0 A+B+ | 53.5 | 1/1 | | ATCC 43255 (CCUG 19126, VPI 10463) | Type 0 A+B+ | 5.35 | 3/4 | | ATCC 43598 (1470) | Type VIII A-B+ | 177 | 3/3 | | ATCC 43598 (1470) | Type VIII A-B+ | 88.5 | 3/3 | | ATCC 43598 (1470) | Type VIII A-B+ | 17.7 | 1/3 | The following Table shows performance of the Portrait Toxigenic C. difficile Assay on 20 replicates of two C. difficile strains for establishing LoD (CFU/test). | <i>C. difficile</i> strains | Toxinotype | Tested<br>CFU/test | <i>C. difficile</i> detected | |---------------------------------------|--------------------|--------------------|------------------------------| | ATCC 43255 (CCUG 19126, VPI<br>10463) | Type 0 A+B+ | 39 | 20/20 | | ATCC 43598 (1470) | Type VIII A-<br>B+ | 39 | 20/20 | {2}------------------------------------------------ - b. In addition to the 2 strains used to determine the assay LOD, 44 additional strains of Toxigenic C. difficile were tested in replicates of 3 at concentrations just above the LOD (48 CFU/test), All strains were correctly identified as positive (including four NAP1/B1/027 strains: 2004013, 2004118, 2009292, and ATCC BAA-1805) by the Portrait Toxigenic C. difficile Assay. Toxinotypes and strains tested: Type 0 Strains: 2004111, 2004205, 2004206, 2005022, 2005283, 2006017, 2007070, 2007302, 2008222, 2009078, 2009087, 2009141, Type 0, A+B+: ATCC 9689(90556-M6S), Type A-B+: CCUG 37782 , Type A+B+: ATCC 17857 (870), ATCC43594 (1253), ATCC43594 (W1194), ATCC 43596 (545), ATCC43599 (2022), ATCC 43600 (2149), ATCC 51695 (BDMS 18 AN), ATCC 700792 (14797-2), ATCC BAA-1382 (630), CCUG 9004, CCUG 9018, CCUG 37766, CCUG 37770, CCUG 37774, CCUG 37776, CCUG 37783. CCUG 37784. ATCC BAA-1814. TYPE III: 2004013*, 2004118*, 2005359*, 2009292*, TYPE III A+B+: ATCC BAA-1805, TYPE V: 2005088*, 2005325*, 2007217*, 2007816*, 2007838*,TYPEVIII: 2006376*,TYPE X A-B+: CCUG 20309 (8864) *C. difficile isolates obtained from the CDC - c. These studies were done to assess the potential cross-reactivity of the Portrait Toxigenic C. difficile Assay with medically relevant levels of bacteria, viruses and fungi. Bacteria and fungi were tested at concentrations > 6 x 106 CFU/mL or 1 x 105 TCID50/mL. No cross reactivity was observed. Bacterial strains tested: Aeromonas hydrophila, Bacteroides fragilis, Campylobacter coli, Campylobacter fetus, Campylobacter jejuni, Citrobacter freundii, Clostridium difficile (A-,B-), Clostridium perfringens. Clostridium sordellii. Enterobacter cloacae. Enterococcus faecalis. Enterococcus faecium van A, Escherichia coli, Escherichia coli 0157:H7, Escherichia fergusonii, Escherichia hermannii, Helicobacter pylori. Klebsiella pneumoniae, Lacotococcus lactis, Listeria monocytogenes, Peptostreptococcus anaerobius, Plesiomonas shigelloides, Proteus vulgaris, Pseudomonas aeruginosa, Pseudomonas fluorescens, Salmonella enterica, serovar Typhimurium (group B), Salmonella enterica, serovar Choleraesuis (group C1), Salmonella enterica, serovar Newport (group C2), Salmonella enterica, serovar Typhi (group D), Salmonella enterica, serovar Newington (group E), Serratia liquefaciens, Serratia marcescens, Shigella boydii, Shigella flexneri, Shigella sonnei, Staphylococcus aureus, Staphylococcus aureus Cowan 1, Staphylococcus epidermidis, Vibrio parahaemolyticus, Yersinia entercolitica. Viruses: Adenovirus Type 40, Adenovirus Type 41, Coxsackievirus Type B4, Echovirus Type 11, Rotavirus. Fungi: Candida albicans. Parasites: Cryptosporidium parvum (gDNA), Giardia intestinalis WB clone C6 gDNA. - d. In addition to the Specificity/Cross reactivity testing, the Portrait toxigenic C. difficile Assay was tested against the same organisms that were used in the Analytical Specificity panel at the specified concentrations against two strains of toxigenic C. difficile spiked into the pooled human stool samples at two times the limit of detection (73 CFU/test). The strains tested were: ATCC 43255 (Toxinotype 0 A+B+) and ATCC 43598 (toxinotype VIII A-B+). All organisms were tested against each strain in triplicate and the Portrait results were positive for all microorganisms tested across both strains. {3}------------------------------------------------ Interfering Substances: The following potentially inhibiting substances were tested without showing Assay Interference: | Substance | Active Ingredient | Substance | Active Ingredient | |-----------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------|--------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | Anusol® Plus (TUCKS) | Mineral oil, pramoxine HCl, Zinc<br>oxide | Moist Towelettes | water, aloe, glycerin, polysorbate 20,<br>disodium cocoamphodiacetate,<br>tocopheryl acetate,<br>methylchloroisothiazolinone,<br>methylisothiazolinone, quaternium-<br>15, potassium sorbate, disodium<br>EDTA, Citric acid, fragrance | | Barium sulfate | Barium sulfate | Miconazole 2% cream (Rite Aid) | Miconazole nitrate 2% | | Calcium carbonate (TUMS) | Calcium carbonate | Mucin (porcine) | | | Cimetidine (Tagamet HB 200) | Cimetidine | Naproxen | Naproxen | | Fecal fats | Stearic acid | (Prilosec OTC) | Omeprazole magnesium | | Fleet® CB (liquid glycerin<br>laxative) | Glycerin | Pepto-Bismol® Proctor & Gamble | Bismuth subsalicylate | | Hydrocortisone Cream<br>(Cortizone-10 max strength) | Hydrocortisone 1% | Preparation H® Wyeth | Glycerin, Phenylephrine HCl,<br>Pramoxine, White petrolatum | | Imodium® McNeil-PPC | Loperamide HCl | Senna laxative (Rite Aid) | Sennosides | | Kaopectate® Chattem | Bismuth subsalicylate | Vancomycin Fluka | Vancomycin | | K-Y Jelly® McNeil-PPC | water, glycerin,<br>hydroxyethylcellulose, chlorhexidine<br>gluconate, gluconolactone,<br>methylparaben, sodium hydroxide | Vaseline Unilever | Petroleum jelly | | Metranidazole Actavis (0.75%) | Metranidazole | Whole Blood | | Reproducibility: Reproducibility studies were performed in-house and at two external clinical sites which were provided with masked coded panels of low, moderate and high concentrations of C. difficile. Over the course of five days, two runs were performed with three replicates of each sample per run on each day. A minimum of two operators performed the runs at each site and two different lots of disposable Test Cartridges were used. Results of the Reproducibility studies are summarized in the table below. {4}------------------------------------------------ ### Reproducibility Study Results | Sample Type | % agreement* | | | | |-------------------|---------------|-------------------|-------------------|-------------| | | In-house site | Site 1 (external) | Site 4 (external) | All Sites | | Moderate Positive | 30/30 100% | 30/30 100% | 28/30 93.3% | 88/90 97.8% | | Low Positive | 30/30 100% | 30/30 100% | 27/30 90.0% | 87/90 96.7% | | High Negative | 27/30 90.0% | 29/30 96.7% | 30/30 100% | 86/90 95.6% | * For Moderate Positive and Low Positive samples, % agreement = 'C. difficile positive' calls/total runs. For High Negative samples, % agreement = 'C. difficile ' negative calls/total runs. + Site 1, Clarion Health Indianapolis, IN (Dr. Gerald Denys, PI) ‡ Site 4, Medical College of Wisconsin, Milwaukee, WI (Dr. Nate Ledeboer , PI) A precision study was also performed in-house over the course of 12 days. Each day two runs were performed using different operators and two replicates of each sample per run. | Sample Type | % agreement* | | |-------------------|--------------|-------| | Moderate Positive | 58/58 | 100% | | Low Positive | 57/58 | 98.3% | | High Negative | 54/58 | 93.1% | Results of the in-house Precision Study were as follows: * For Moderate Positive and Low Positive samples, % a greement = 'C. difficile positive' /total runs . For High Negative samples , % agreement = 'C. difficile 'negative/total runs . The results for the reproducibility and precision studies of the Portrait Toxigenic C. difficile Assay were within the expected percent across all three sites. #### BIOCOMPATIBILITY/MATERIALS N/A ### SHELF LIFE/STERILITY The Portrait Analyzer has no sterility requirements. The Portrait Toxigenic C. difficile Assay cartridge will be tested to achieve a minimum of 26 weeks stability. {5}------------------------------------------------ #### ANIMAL STUDIES N/A ## ELECTROMAGNETIC COMPATIBILITY AND ELECTRICAL SAFETY The Portrait Analyzer was tested and complied with the requirements for electromagnetic compatibility. # MAGNETIC RESONANCE (MR) COMPATIBILITY N/A MECHANICAL SAFETY N/A SOFTWARE | Version: Portrait Analyzer software version 1.5.23.19 | | | |-------------------------------------------------------|-----|----| | Level of Concern: Moderate | | | | | Yes | No | | Software description: | X | | | Device Hazard Analysis: | X | | | Software Requirements Specifications: | X | | | Architecture Design Chart: | X | | | Design Specifications: | X | | | Traceability Analysis/Matrix: | X | | | Development: | X | | | Verification & Validation Testing: | X | | | Revision level history: | X | | | Unresolved anomalies: | X | | The information provided is adequate for each of the items listed above. Links and relationships between software requirements, specifications, testing and software related hazards are summarized in a Traceability Matrix. In summary, the Analyzer function is controlled by software communicating with hardware drivers and responding to signals from various sensors that monitor fluid, thermal and optical conditions on the assay cartridge. Performance of all individual modules (e.g. Thermal PID Module. Optical Sense Module, etc.) has undergone verification testing at the module level (Intra-Module and Regression Testing), All system related functions have undergone system level verification testing to confirm that all interrelated systems meet all performance specifications. ## SUMMARY OF CLINICAL INFORMATION Clinical performance of the Portrait toxigenic C. difficile Assay was determined in a multi-site clinical evaluation at 4 US institutions by comparison of the Portrait Assay results to reference culture/cell cytotoxicity (TBC/CCNA) testing. A total of 540 eligible specimens were tested with the Portrait toxigenic C. difficile Assay vs. {6}------------------------------------------------ TBC/CCNA. Relative to TBC/CCNA, Portrait toxigenic C. difficile Assay demonstrated a sensitivity of 98.0% and a specificity of 90.9% for toxigenic C. difficile when compared to the reference method. The resulting Negative predictive value NPV is 99.5 % and a Positive predictive value of 71.4%. | | Cytotoxic bacterial | | | |----------------|---------------------|----------|-------| | Portrait<br>C. | Positive | Negative | Total | | Positive | 100 | 40 | 140 | | Negative | 2 | 398 | 400 | | Totals | 102 | 438 | 540 | | | | CI95 | |-------------|---------------|------------| | Sensitivity | 100/102 98.0% | 92.4-99.6% | | Specificity | 398/438 90.9% | 87.7-93.3% | | PPV | 71.4% | 63.1-78.6% | | NPV | 99.5% | 98.0-99.9% | CI95: confidence intervals at 95% PPV: Positive predictive value NPV: Negative predictive value # LABELING Labeling has been provided which includes instructions for use and an appropriate prescription statement as required by 21 CFR 801.109(b) # RISKS TO HEALTH The table below identifies the risks to health that may be associated with use of the Clostridium difficile toxin gene amplification assay and the measures recommended to mitigate these risks. | Identified Risk | Mitigation Method | |-----------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------| | A false positive test result for an<br>individual may lead to inappropriate use<br>of antibiotics for treatment | Kit includes quality control material and<br>instructions for use. | | A false negative test result for an<br>individual may lead to a potential delay<br>in treatment | Kit includes quality control material and<br>instructions for use | | Failure of the test to perform properly | Product labeling provides instructions<br>for use and limitations of the assay | | Failure to properly interpret the test<br>results | Product labeling describes interpretation<br>of results | {7}------------------------------------------------ # SPECIAL CONTROLS: In combination with the general controls of the FD&C Act, the Portrait Toxigenic C. difficile Assay is subject to the following special controls: - 1. The special controls for the Clostridium difficile toxin gene amplification assay are contained in the guidance document: "Class II Special Controls Guidance Document: Toxin Gene Amplification Assays for the Detection of Clostridium difficile." ## CONCLUSION The De Novo petition for the Portrait Toxigenic C. difficile assay is granted and the device is classified under the following: Product Code: OZN Device Type: Clostridium difficile toxin gene amplification assay Class: II Regulation: 21 CFR 866.3130