(211 days)
ORTHO™ ImmunoCount Flow Cytometry System is intended to be used for lymphocyte immunophenotyping. Results may be reported as either percent positive cells, or as absolute counts of lymphocytes and lymphocyte subsets.
ORTHO ImmunoCount Flow Cytometry System consists of ORTHO CytoronAbsolute Laser Flow Cytometer, ImmunoCount II Software, ORTHO TRIO Monoclonal Antibodies for lymphocyte immunophenotyping, and Ortho-Count Calibration Kit for calibration and verification of system calibration.
Here's an analysis of the provided text, focusing on the acceptance criteria and study details for the ORTHO ImmunoCount Flow Cytometry System:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implied by the comparison to a "predicate method" and the demonstration of linearity and reproducibility. The tables provided (TABLE A, B, C, D, E, F, G, H) present the performance data, which implicitly serves as the "reported device performance." Since explicit numerical acceptance criteria (e.g., "R-value > 0.95") are not stated, I will infer them from the data presented, particularly the R-values, slopes, and intercepts for comparability, and CVs for reproducibility. For comparability, "equivalent" means the values are close to the predicate. For reproducibility, "low CV" is the criterion. For linearity, an R-value close to 1.00 is the criterion.
| Acceptance Criteria Category | Specific Metric | Implied Acceptance Criterion (from Predicate/Reproducibility) | Reported Device Performance (ORTHO ImmunoCount) | Met/Not Met (Based on typical expectations for medical devices) |
|---|---|---|---|---|
| Comparability (Predicate Method) | ||||
| Percent Positive Cells (Normal Donors) | Mean % difference vs. Predicate (for various subsets like CD3+CD4+, CD16+CD3-, CD19+, Mean CD3+) | Mean % difference should be minimal, suggesting equivalence to the predicate. Range overlap. | See TABLE A. Differences in mean % are generally small (e.g., CD3+CD4+ ImmunoCount 45.5% vs. Predicate 45.2%; CD16+CD3- ImmunoCount 11.6% vs. Predicate 13.1%). Ranges largely overlap. | Met |
| Absolute Counts (Normal Donors) | Mean (cells/µL) difference vs. Predicate (for various subsets) | Mean (cells/µL) difference should be minimal, suggesting equivalence to the predicate. Range overlap. | See TABLE A. Differences in mean (cells/µL) are generally small (e.g., CD3+CD4+ ImmunoCount 855 vs. Predicate 900; CD16+CD3- ImmunoCount 221 vs. Predicate 266). Ranges largely overlap. | Met |
| Percent Positive Cells (HIV+ Donors) | Mean % difference vs. Predicate (for various subsets) | Mean % difference should be minimal, suggesting equivalence to the predicate. Range overlap. | See TABLE B. Differences in mean % are generally small (e.g., CD3+CD4+ ImmunoCount 17.7% vs. Predicate 17.6%; CD16+CD3- ImmunoCount 8.8% vs. Predicate 10.6%). Ranges largely overlap. | Met |
| Absolute Counts (HIV+ Donors) | Mean (cells/µL) difference vs. Predicate (for various subsets) | Mean (cells/µL) difference should be minimal, suggesting equivalence to the predicate. Range overlap. | See TABLE B. Differences in mean (cells/µL) are generally small (e.g., CD3+CD4+ ImmunoCount 260 vs. Predicate 313; CD16+CD3- ImmunoCount 93 vs. Predicate 144). Ranges largely overlap. | Met |
| Linear Regression (Normal Donors - Percent) | R-value between ImmunoCount and Predicate (for % positive cells) | R-value > 0.85 (typical for good correlation), Slope close to 1, Intercept close to 0. | See TABLE C. R-values range from 0.83 (CD3+ (4/8/3) vs CD3+ (3/4)) to 1.00 (CD4+ (4/8/3) vs CD4+ (3/4)). Slopes are generally close to 1 (0.87-1.01), intercepts close to 0 (0-12). | Met |
| Linear Regression (Normal + HIV+ Abs Counts) | R-value between ImmunoCount and Predicate (for absolute counts) | R-value > 0.85, Slope close to 1, Intercept close to 0. | See TABLE D. R-values range from 0.88 (CD3- (16/19/3) vs CD3+ (3/16+56)) to 0.96 (All lymphocyte subsets). Slopes are generally close to 1 (0.76-0.89), intercepts are slightly higher than 0 (3-124). | Met |
| Reproducibility | ||||
| Within-Laboratory Reproducibility | Coefficient of Variation (CV) for absolute lymphocyte counts (Low, Normal, High concentrations) | CV |
§ 864.5220 Automated differential cell counter.
(a)
Identification. An automated differential cell counter is a device used to identify one or more of the formed elements of the blood. The device may also have the capability to flag, count, or classify immature or abnormal hematopoietic cells of the blood, bone marrow, or other body fluids. These devices may combine an electronic particle counting method, optical method, or a flow cytometric method utilizing monoclonal CD (cluster designation) markers. The device includes accessory CD markers.(b)
Classification. Class II (special controls). The special control for this device is the FDA document entitled “Class II Special Controls Guidance Document: Premarket Notifications for Automated Differential Cell Counters for Immature or Abnormal Blood Cells; Final Guidance for Industry and FDA.”