(203 days)
The Caltag Fetal Hemoglobin Test, containing either FITC, R-PE or TRI-COLOR® conjugated monoclonal antibodies to fetal hemoglobin (hemoglobin F), is intended for the identification followed by enumeration of fetal red blood cells. Fetal red cells are identified by the presence of fetal hemoglobin by a flow cytometric method. Fetal cells, when found in the maternal circulation, may be an indication of fetal or maternal complications. The hemorrhage of Rh+ fetal blood into Rh- maternal blood may result in the formation of sensitizing Rh antibodies in the mother. This Rh immunization may be prevented by the administration to the mother of Rh immune globulin (RhIg) soon after delivery. The Caltag Fetal Hemoglobin Test may be used as an aid in detecting incompatible fetal-maternal hemorrhage and determining the need for immunoprophylaxis with Rh immune globulin.
An anticoagulated peripheral blood sample is drawn from an appropriate donor. The erythrocyte count is determined and adjusted, followed by brief fixation of the cells in gluteraldehyde. Fixed and washed cells are permeabilized with a detergent in a manner that is frequently used to enable macromolecules such as monoclonal antibodies to penetrate cellular membranes. Caltag HbF FITC, HbF R-PE and HbF TRI-COLOR monoclonal antibodies bind to fetal hemoglobin in fetal red cells. To identify cells containing fetal hemoglobin, fixed and permeabilized cells are incubated with the monoclonal antibody, and washed to remove unbound antibody. Antibody stained cells are subsequently analyzed by flow cytometric methods. Positive and negative control samples must be used with sample analysis, to establish that all reagents are performing in a consistent manner and that the positive fluorescence attributed to antibody-stained fetal red cells is differentiated from unstained normal red blood cells, leukocytes and any cellular debris. If cord blood is not available for the performance of positive controls, the assay cannot be performed reliably. The recommended positive control samples consist of both 1% and 5% fetal erythrocyte-containing placental cord blood in normal adult blood. The recommended negative control sample consists of 1% anticoagulated sample from a normal male or non-pregnant adult female.
Here's a breakdown of the acceptance criteria and the study details for the Caltag Fetal Hemoglobin Test, based on the provided text:
Acceptance Criteria and Device Performance
The core of the acceptance criteria for this device revolves around demonstrating substantial equivalence to the predicate device (Sure-Tech Fetal Hemoglobin Test, K892241). This is primarily shown through correlation studies and assessments of expected values and reproducibility.
1. Table of Acceptance Criteria and Reported Device Performance
Given that this is a 510(k) summary for a diagnostic device, the acceptance criteria are not explicitly stated as pass/fail thresholds in the same way they might be for a therapeutic device. Instead, the performance is demonstrated by showing strong correlation with the predicate device and acceptable levels of specificity, reproducibility, and linearity.
| Acceptance Criteria Category | Specific Metric (Implicit) | Acceptance Value (Implicit) | Reported Device Performance |
|---|---|---|---|
| Correlation with Predicate Device (Kleihauer-Betke) | r² value (prepared samples, flow cytometer - FACscan) | High correlation (e.g., > 0.95 or similar to predicate) | HbF FITC vs KB: 97.95 (mean % positive: 4.54 vs 4.51) |
| HbF R-PE vs KB: 98.16 (mean % positive: 4.50 vs 4.41) | |||
| HbF TC vs KB: 97.98 (mean % positive: 4.49 vs 4.41) | |||
| Correlation with Predicate Device (Kleihauer-Betke) | r² value (prepared samples, flow cytometer - EPICS-XL) | High correlation (e.g., > 0.95 or similar to predicate) | HbF FITC vs KB: 98.48 (mean % positive: 4.22 vs 4.40) |
| HbF R-PE vs KB: 98.41 (mean % positive: 4.24 vs 4.40) | |||
| HbF TC vs KB: 97.96 (mean % positive: 4.20 vs 4.40) | |||
| Correlation with Predicate Device (Kleihauer-Betke) | r² value (patient samples, flow cytometer - FACscan) | High correlation (e.g., > 0.95 or similar to predicate) | HbF FITC vs KB: 96.80 (mean % positive: 0.51 vs 0.51) |
| HbF R-PE vs KB: 96.84 (mean % positive: 0.50 vs 0.51) | |||
| HbF TC vs KB: 97.50 (mean % positive: 0.47 vs 0.51) | |||
| Correlation with Predicate Device (Kleihauer-Betke) | r² value (patient samples, flow cytometer - EPICS-XL, Site 2) | High correlation (e.g., > 0.95 or similar to predicate) | HbF FITC vs KB: 98.34 (mean % positive: 0.22 vs 0.20) |
| Correlation with Predicate Device (Kleihauer-Betke) | r² value (prepared samples, flow cytometer - EPICS-XL, Site 2) | High correlation (e.g., > 0.95 or similar to predicate) | HbF FITC vs KB: 85.50 (mean % positive: 1.52 vs 1.61) - Lower than others, but context of small n (15) and range of 0-3.0% |
| Correlation with Predicate Device (Kleihauer-Betke) | r² value (patient samples, flow cytometer - EPICS-XL, Site 3) | Acceptable correlation | HbF R-PE vs KB: 64.00 (mean % positive: 0.08 vs 0.11) - Notably lower, but potentially due to very low % positive cells and small n (13) |
| Correlation with Predicate Device (Kleihauer-Betke) | r² value (prepared samples, flow cytometer - EPICS-XL, Site 3) | High correlation (e.g., > 0.95 or similar to predicate) | HbF R-PE vs KB: 84.01 (mean % positive: 1.38 vs 1.40) |
| Intra-lab Reproducibility | % CV (high level) | Low variability (e.g., < 10%) | HbF FITC: 2.42, HbF R-PE: 4.25, HbF TC: 3.84 |
| % CV (mid level) | Low variability (e.g., < 10%) | HbF FITC: 4.30, HbF R-PE: 2.66, HbF TC: 4.16 | |
| % CV (low level) | Low variability (e.g., < 10%) | HbF FITC: 2.26, HbF R-PE: 4.75, HbF TC: 4.58 | |
| Inter-lab Reproducibility | % CV (across sites, various levels) | Low variability (e.g., < 10%) | Ranging from 1.37% to 7.40% across sites and levels (e.g., Site 1 FITC high: 1.48%, Site 3 R-PE mid: 7.40%) |
| Specificity | No staining of non-fetal cells | Complete specificity | No staining of lymphocyte, monocyte, granulocyte regions, red blood cells (adult), and platelets |
| Linearity of Measurement | r² value (0.0-5.0% cord blood) | High linearity (e.g., > 0.99) | HbF FITC: 99.97, HbF R-PE: 99.96, HbF Tri-Color: 99.98 |
| Detection of 100% Cord Blood | Mean % positive (close to 100%) | Near 100% detection | HbF FITC: 95.66%, HbF R-PE: 96.70%, HbF TRI-COLOR: 95.60% |
| Expected Values in Normal Donors | Establish 95% Reference Interval | Range for normal non-pregnant individuals | Mean % positive 0.03-0.04; 95% reference interval 0.00-0.15% |
2. Sample Size and Data Provenance
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Correlation Studies (Test Set):
- Site 1: 50 prepared samples, 30 patient samples.
- Site 2: 15 prepared samples, 38 patient samples.
- Site 3: 15 prepared samples, 13 patient samples.
- Total: 80 prepared samples, 81 patient samples (summing across sites, noting some overlap in prepared samples).
- Provenance: "patient samples were obtained from women having clinical indications that were consistent with fetal-maternal hemorrhage and prepared samples consisted of mixtures of fetal cord blood in normal adult blood." The studies were conducted in three independent laboratories in geographically diverse areas within the United States. This implies retrospective for patient samples with specific clinical indications, and prospectively prepared for mixed samples.
-
Expected Values Data:
- Sample Size: 161 adult female normal donors.
- Provenance: Collected from "adult female normal donors" across "three independent laboratories" in "geographically diverse areas within the United States, including the Northern, South-central and Western regions." Donors were of "differing ethnic origins, including adult Caucasians, Blacks, Orientals and Hispanics." This data is prospective.
-
Specificity Data:
- Sample Size: Not explicitly stated but "blood samples were obtained from healthy normal donors of Caucasian, Black, Hispanic and Oriental ethnic origins." (likely a subset of the 161 from expected values, or similar cohort).
- Provenance: Healthy normal donors, likely prospective.
-
Reproducibility Data (Intra-lab & Inter-lab):
- Sample Size: 6 replicated determinations for each antibody at high, medium, and low levels, performed across three independent laboratories. The samples were "varying mixtures of placental cord blood in normal adult blood." For inter-lab, "unstained and unfixed samples containing mixtures of cord blood in normal adult blood representing the appropriate ranges were prepared by one of the participating laboratories for staining and analysis by each of the participating laboratories." This involved prepared samples, likely prospective.
-
Linearity of Measurement:
- Sample Size: 10 samples (mixtures of cord blood cells in normal adult blood).
- Provenance: Prepared samples, prospective.
-
Detection of 100% Cord Blood:
- Sample Size: 5 different cord blood samples.
- Provenance: Cord blood samples, likely prospective.
3. Number of Experts Used to Establish Ground Truth and Qualifications
- The document does not explicitly mention "experts" being used to establish ground truth for this device in the sense of trained clinicians making diagnoses that the device is then compared against.
- Instead, the Kleihauer-Betke (KB) test is used as the comparative "ground truth" to which the Caltag device is correlated. The KB test is an established, widely used microscopic staining method for detecting fetal hemoglobin. The interpretation of KB tests typically involves trained laboratory technicians or pathologists.
- The document states that the correlation study was conducted in 3 independent laboratories, implying that personnel trained in both flow cytometry and the KB method were involved in generating the data. No specific qualifications (e.g., "Radiologist with 10 years of experience") are provided for these individuals, as the device measures a quantitative biological marker rather than interpreting images.
4. Adjudication Method for the Test Set
- No explicit adjudication method (e.g., 2+1, 3+1) is mentioned.
- The "ground truth" for the correlation studies was the result from the Kleihauer-Betke (KB) test. This is a laboratory test with an established protocol, and the agreement is between the Caltag device's quantitative output and the KB test's quantitative output, rather than human expert interpretations requiring adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No MRMC comparative effectiveness study was done.
- This device is a diagnostic assay that directly quantifies fetal hemoglobin. It is not an AI-assisted interpretation tool for human readers, so comparing human readers with and without AI assistance is not applicable to this type of device.
6. Standalone Performance (Algorithm Only without Human-in-the-Loop)
- Yes, the performance presented for the Caltag Fetal Hemoglobin Test is its standalone performance. The flow cytometric analysis is an automated process after sample preparation and staining with the monoclonal antibodies. The reported percentages of positive cells (e.g., mean % positive, r² values) represent the device's output. While human technicians perform the sample preparation and operate the flow cytometer, the measurement itself is performed by the instrument and its associated software, making it a standalone quantitative measurement.
7. Type of Ground Truth Used
- The primary ground truth used for comparison and validation is the Kleihauer-Betke (KB) microscopic staining method. This is a laboratory-based, established diagnostic test for quantifying fetal red blood cells.
- For the 100% cord blood samples, the "ground truth" is the known composition of the sample (i.e., that it should be 100% fetal cells), effectively using known sample composition.
- For expected values and specificity, healthy normal donors were the "ground truth" for what constitutes a normal, non-pregnant sample result.
8. Sample Size for the Training Set
- The document describes studies for validation and substantial equivalence, not a machine learning "training set" in the modern sense. Therefore, there isn't a "training set" sample size like one would find for an AI/ML algorithm.
- The "expected value" data (161 donors) and "specificity" data implicitly contribute to defining the normal operating parameters and behavior of the test, which could be considered analogous to internal validation or establishing reference ranges.
9. How the Ground Truth for the Training Set Was Established
- As mentioned, there isn't a "training set" in the AI/ML context.
- For the data that helps define the device's characteristics (e.g., expected values, specificity), the ground truth was established by:
- Using healthy normal donors to determine normal ranges and confirm specificity (i.e., no fetal cells expected, or very low baseline).
- Using known prepared samples (mixtures of cord blood and adult blood) to assess linearity and reproducibility. These samples have a known, pre-determined percentage of fetal cells.
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SEP 1 7 1999
510(K) SUMMARY SUMMARY OF SAFETY AND EFFECTIVENESS DATA
BORATORIE:
Caltag Fetal Hemoglobin Test for the Detection of Fetal Red Blood Cells in the Maternal Circulation (Fetal-Maternal Hemorrhage)
NAME AND LOCATION OF THE MANUFACTURER: Caltag Laboratories, Inc. 1849 Old Bayshore Highway Suite 200 Burlingame, CA 94010 (800) 874-4007
NAME OF CONTACT PERSON: Robert C. Johnson Executive Vice President Caltag Laboratories, Inc.
DATE OF PREPARATION OF THE SUMMARY: July 09, 1999
TRADE NAME OF THE DEVICE:
Caltag Fetal Hemoglobin Test for the Detection of Fetal Red Blood Cells in the Maternal Circulation (Fetal-Maternal Hemorrhage) ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・
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COMMON NAME:
Caltag Fetal Hemoglobin Test
CLASSIFICATION NAME:
Fetal Hemoglobin Assay; 21CFR 864.7455 Product Code: GHQ
LEGALLY MARKETED (PREDICATE) DEVICE TO WHICH THE MANUFACTURER IS CLAIMING SUBSTANTIAL EQUIVALENCE:
Caltag Fetal Hemoglobin Test is substantially equivalent to Sure-Tech Fetal Hemoglobin Test for in vitro diagnostic use (K892241), manufactured by Sure-Tech Diagnostic Associates, Inc., 11012 Un Valle, Suite D, St. Louis, Mo. 63123,
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An anticoagulated peripheral blood sample is drawn from an appropriate donor. The erythrocyte count is determined and adjusted, followed by brief fixation of the cells in gluteraldehyde.
Fixed and washed cells are permeabilized with a detergent in a manner that is frequently used to enable macromolecules such as monoclonal antibodies to penetrate cellular membranes. Caltag HbF FITC, HbF R-PE and HbF TRI-COLOR monoclonal antibodies bind to fetal hemoglobin in fetal red cells. To identify cells containing fetal hemoglobin, fixed and permeabilized cells are incubated with the monoclonal antibody, and washed to remove unbound antibody. Antibody stained cells are subsequently analyzed by flow cytometric methods.
Positive and negative control samples must be used with sample analysis, to establish that all reagents are performing in a consistent manner and that the positive fluorescence attributed to antibody-stained fetal red cells is differentiated from unstained normal red blood cells, leukocytes and any cellular debris. If cord blood is not available for the performance of positive controls, the assay cannot be performed reliably. The recommended positive control samples consist of both 1% and 5% fetal erythrocyte-containing placental cord blood in normal adult blood. The recommended negative control sample consists of 1% anticoagulated sample from a normal male or non-pregnant adult female.
INTENDED USE OF THE DEVICE:
The Caltag Fetal Hemoglobin Test, containing monoclonal antibodies to fetal hemoglobin (hemoglobin F) conjugated with either FITC, R-PE or TRI-COLOR®, is intended for the identification followed by enumeration of fetal red blood cells. Fetal cells are identified by the presence of fetal hemoglobin by a flow cytometric method. The presence of fetal cells in the maternal circulation, resulting from fetalmaternal hemorrhage, may be attributed to a variety of causes, including fetal trauma, various obstetrical emergencies and placental trauma. Hemorrhage of Rh+ fetal blood into Rh- maternal blood may result in the formation of sensitizing Rh antibodies in the mother. This Rh immunization may be prevented by the ---administration to the mother of Rh immune globulin (RhIg) soon after delivery. The Caltag Fetal Hemoglobin Test may be used as an aid in identifying fetal-maternal hemorrhage and determining the need for immunoprophylaxis with immune globulin.
SUMMARY OF TECHNICAL CHARACTERISTICS OF THE DEVICE COMPARED TO THE PREDICATE DEVICE:
| No. | Item | Caltag Test | Predicate Test | Comparison |
|---|---|---|---|---|
| 1. | Intended Use | Enumeration ofFetal cells | Enumeration ofFetal cells | Substantiallyequivalent |
| 2. | Specificity | Fetal hemoglobin | Fetal hemoglobin | Substantiallyequivalent |
| 3. | Target cell | Fetal erythrocyte | Fetal erythrocyte | Substantiallyequivalent |
Comparisons of Caltag and Predicate Fetal Hemoglobin Tests
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| Continued.. | ||||
|---|---|---|---|---|
| 4. | Method ofDetection | Flow Cytometry | Light Microscopy | Differentmethods used |
| 5. | Chemical form | Monoclonalantibody | Pink staining witherythrocin | Substantiallyequivalent |
| 6. | DeviceConfiguration | Diagnostic Kitwith Reagents | Diagnostic Kitwith Reagents | Substantiallyequivalent |
| 7. | Sample prep.methods | Fixed, PermeabilizedWhole Blood | Whole Blood | Substantiallyequivalent |
| 8. | Correlation ofMethods (FACscan & EPICS-XL Site) | |||
| Prepared Samples (n=50) | Substantially | |||
| Mean % Positive | FITC 4.54 | KB 4.51 | equivalent | |
| r squared value | 97.95 | |||
| Mean % Positive | R-PE 4.50 | KB 4.41 | ||
| r squared value | 98.16 | |||
| Mean % Positive | TC 4.49 | KB 4.41 | ||
| r squared value | 97.98 | |||
| Patient Samples (n=30) | Substantially | |||
| Mean % Positive | FITC 0.51 | KB 0.51 | equivalent | |
| r squared value | 96.80 | |||
| Mean % Positive | R-PE 0.50 | KB 0.51 | ||
| r squared value | 96.84 | |||
| Mean % Positive | TC 0.47 | KB 0.51 | ||
| r squared value | 97.50 |
NON-CLINICAL TESTS SUPPORTING A DETERMINATION OF SUBSTANTIAL EQUIVALENCE:
Expected Value Data:
Blood samples were collected from a total of 161 adult female normal donors in an age range of 19-50, with a mean and median age of 33. These consisted of ------approximately 50 female normal donors in each of three independent laboratories. In each laboratory, normal donors were distributed approximately equally among the three age ranges of 19-29, 30-39 and 40-50. A single sample from each donor was analyzed for the determination of expected values of the Caltag FITC. R-PE and TRI-COLOR® monoclonal antibodies to HbF.
The normal donor population consisted of members of differing ethnic origins, including adult Caucasians, Blacks, Orientals and Hispanics. The three independent laboratories were located in geographically diverse areas within the United States, including the Northern, South-central and Western regions.
Normal ranges are expressed as the 95% reference intervals (17), consisting of the mid-95% of values for all donors when rank ordered from lowest to highest percent of fetal cells detected, as indicated on the following table;
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EXPECTED VALUES IN ALL ADULT FEMALE NORMAL DONORS
| procedure | mean% positive | S.D. | 95% ReferenceInterval(Normal Range) | n |
|---|---|---|---|---|
| FITC | 0.03 | 0.04 | 0.00--0.15 | 153 |
| R-PE | 0.04 | 0.05 | 0.00--0.14 | 153 |
| TRI-COLOR | 0.03 | 0.04 | 0.00--0.14 | 153 |
Specificity Data:
This study was conducted to evaluate any staining of blood elements other than fetal erythrocytes by the Caltag HbF monoclonal antibodies. Blood samples were obtained from healthy normal donors of Caucasian, Black, Hispanic and Oriental ethnic origins.
Samples of each donor were stained with Caltag HbF FITC, HbF R-PE and HbF TRI-COLOR monoclonal antibodies. Cells contained in the lymphocyte, monocyte and granulocyte regions were selected for analysis. Separate sample were prepared for analysis of red blood cells and platelets and were stained with each of the Caltag monoclonal antibodies.
The specificity study indicated no staining of any of the indicated blood elements by the Caltag HbF monoclonal antibodies in samples from normal donors.
Reproducibility Data: intra-lab
Intra-lab reproducibility for the Caltag HbF FITC, HbF R-PE and HbF TRI-COLOR (TC) conjugated monoclonal antibodies was determined by performing 6 replicated determinations for each antibody in each of three ranges: high, medium and low. Thus, a total of 18 determinations were performed for each HbF antibody. In this manner, reproducibility was demonstrated throughout the entire measurement range for the Caltag Fetal Hemoglobin Test.
The 6 determinations for each range were performed by the staining, processing and analysis of 6 separate samples consisting of varying mixtures of placental cord blood in normal adult blood. Fetal cells were selected for the analysis of percent cells stained in each of the three ranges.
The study was performed in each of three independent laboratories, in the manner that each laboratory obtained, stained and analyzed separate blood samples.
The following data are representative:
| procedure | Level | mean% positive | S.D. | % CV | n |
|---|---|---|---|---|---|
| HbF FITC | high | 9.51 | 0.22 | 2.42 | 6 |
| mid | 5.10 | 0.22 | 4.30 | 6 | |
| low | 2.19 | 0.05 | 2.26 | 6 | |
| procedure | Level | mean% positive | S.D. | % CV | n |
| HbF R-PE | high | 9.61 | 0.40 | 4.25 | 6 |
| mid | 5.10 | 0.14 | 2.66 | 6 | |
| low | 2.14 | 0.10 | 4.75 | 6 |
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| procedure | Level | mean% positive | S.D. | % CV | n |
|---|---|---|---|---|---|
| HbF TC | high | 9.64 | 0.37 | 3.84 | 6 |
| mid | 5.13 | 0.21 | 4.16 | 6 | |
| low | 2.23 | 0.10 | 4.58 | 6 |
Reproducibility Data, inter-lab
Inter-lab reproducibility for the Caltag HbF FITC, HbF R-PE and HbF TRI-COLOR (TC) conjugated monoclonal antibodies was determined by performing 6 replicated determinations for each antibody in each of three ranges; high, medium and low. In this manner, reproducibility was demonstrated throughout the entire measurement range for the Caltag Fetal Hemoglobin Test.
The 6 determinations for each range were performed by the staining, processing and analysis of 6 separate samples consisting of varying mixtures of placental cord blood in normal adult blood. Fetal cells were selected for the analysis of percent cells stained in each of the three ranges.
The study was performed in each of three laboratories. All laboratories stained and analyzed the same samples.
Unstained and unfixed samples containing mixtures of cord blood in normal adult blood representing the appropriate ranges were prepared by one of the participating laboratories for staining and analysis by each of the participating laboratories. The following data were obtained:
| SITE 1procedure | Level | mean% positive | S.D. | % CV | n |
|---|---|---|---|---|---|
| HbF FITC | high | 6.34 | 0.09 | 1.48 | 6 |
| mid | 4.05 | 0.08 | 2.09 | 6 | |
| low | 1.48 | 0.04 | 2.91 | 6 | |
| procedure | Level | mean% positive | S.D. | % CV | n |
| HbF R-PE | high | 7.90 | 0.29 | 3.64 | 6 |
| mid | 5.35 | 0.30 | 5.60 | 6 | |
| low | 2.84 | 0.21 | 7.34 | 6 | |
| procedure | Level | mean% positive | S.D. | % CV | n |
| HbF TC | high | 7.43 | 0.10 | 1.37 | 6 |
| mid | 4.37 | 0.11 | 2.57 | 6 | |
| low | 1.60 | 0.07 | 4.55 | 6 | |
| SITE 2procedure | Level | mean% positive | S.D. | % CV | n |
| HbF FITC | high | 8.84 | 0.21 | 2.32 | 6 |
| mid | 5.69 | 0.13 | 2.36 | 6 | |
| low | 2.44 | 0.08 | 3.28 | 6 |
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| procedure | Level | mean% positive | S.D. | % CV | n |
|---|---|---|---|---|---|
| HbF R-PE | highmidlow | 8.815.702.36 | 0.220.140.04 | 2.512.451.89 | 666 |
| procedure | Level | mean% positive | S.D. | % CV | n |
| HbF TC | highmidlow | 8.825.682.41 | 0.120.150.05 | 1.392.691.90 | 666 |
| SITE 3procedure | Level | mean% positive | S.D. | % CV | n |
| HbF FITC | highmidlow | 8.955.852.57 | 0.360.230.14 | 4.043.865.32 | 666 |
| procedure | Level | mean% positive | S.D. | % CV | n |
| HbF R-PE | highmidlow | 8.435.602.38 | 0.120.410.07 | 1.447.403.16 | 666 |
| procedure | Level | mean% positive | S.D. | % CV | n |
| HbF TC | highmidlow | 8.705.652.41 | 0.460.180.17 | 5.243.127.13 | 666 |
Linearity of measurement was determined for samples consisting of mixtures of cord blood cells in normal adult blood in the range of 0.0-5.0% cord blood cells. This range was selected to represent the entire range of values for the percent of fetal cells that are likely to be experienced in fetal-maternal hemorrhage. The linear regression method was used to plot the known expected values versus the observed values for the percent of fetal cells determined by the flow cytometric method for the Caltag FITC, R-PE and TRI-COLOR® monoclonal antibodies to HbF:
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LINEARITY OF MEASUREMENT
| procedure | r2 value | slope | Y intercept | n |
|---|---|---|---|---|
| HbF FITC | 99.97 | 1.01 | -0.04 | 10 |
| HbF R-PE | 99.96 | 1.02 | -0.03 | 10 |
| HbF Tri-Color | 99.98 | 1.02 | -0.02 | 10 |
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An additional study was conducted to identify saturating conditions for each of the Caltag monoclonal antibodies, consisting of preparations of cord blood alone (100% cord blood). Five different cord blood samples were stained and analyzed in a single laboratory, to determine the ability of the Caltag Fetal Hemoglobin Test to detect all fetal cells present, and to assure that the concentration and potency of the HbF monoclonal antibodies is sufficient to detect all fetal cells in a test sample. Therefore, samples employed in this study contained a greater than tenfold higher content of fetal cells than would be expected to occur in clinical specimens.
Summary of values obtained for the percent of fetal cells detected by the Caltag HbF FITC, HbF R-PE and HbF TRI-COLOR antibodies in 100% cord blood samples:
| procedure | mean% positive | S.D. | % CV | n |
|---|---|---|---|---|
| HbF FITC | 95.66 | 3.88 | 4.05 | 5 |
| HbF R-PE | 96.70 | 2.70 | 2.80 | 5 |
| HbF TRI-COLOR | 95.60 | 2.58 | 2.70 | 5 |
CLINICAL TESTS SUPPORTING A DETERMINATION OF SUBSTANTIAL EQUIVALENCE
Correlation Data:
The Correlation study was conducted in 3 independent laboratories. Samples were analyzed with the Caltag Fetal Hemoglobin Test and a commercially available test based on the Kleihauer-Betke (KB) microscopic staining method for the detection of fetal hemoglobin in fetal cells (4) in each site. In all studies, confidence intervals are expressed at the 95% limit.
In study site #1, the percent of fetal cells detected by each of the HbF monoclonal antibodies to fetal hemoglobin was correlated with the percent of fetal cells detected by the KB test on patient samples (n=30) and prepared samples (n=50). Patient samples were obtained from women having clinical indications that were consistent with fetal-maternal hemorrhage and prepared samples consisted of mixtures of fetal cord blood in normal adult blood prepared in differing cell ratios in the range of 0-10% fetal cells. This range included up to the equivalent of 500. ml of fetal blood in maternal blood and greatly exceeded the 150--300 ml of fetal blood encountered in the most severe cases of fetal-maternal hemorrhage (3).
In study sites #2, the percent of fetal cells detected by the HbF FITC monoclonal antibody to fetal hemoglobin was correlated with the percent of fetal cells detected by the KB test in patient samples (n = 38) and prepared samples (n = 15) in the range of 0-3.0%. The Caltag test was propared Sumploo (n ----------------------------------------------------------------------------------------------------------------------------------------------------------
In study site #3, the percent of fetal cells detected by the HbF R-PE monoclonal to fetal hemoglobin was correlated with the percent of fetal cells detected by the KB test in patient samples (n = 13) and prepared samples (n = 15) in the range of 0-3.0% and analyzed on the EPICS-XL flow cytometer.
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In study site #1, the same prepared samples (n =50) were analyzed on both the Becton Dickinson Facscan and Coulter EPICS-XL flow cytometers, as follows
Summary of Correlations on FACscan Flow Cytometer Prepared Samples
| Comparisons | Mean %Positive | ConfidenceInterval (95%) | r2value | n |
|---|---|---|---|---|
| HbF FITCKB | 4.544.41 | 3.633.52 | 97.95 | 50 |
| HbF R-PEKB | 4.504.41 | 3.593.52 | 98.16 | 50 |
| HbF TCKB | 4.494.41 | 3.583.52 | 97.98 | 50 |
| HbF FITCHbF R-PE | 4.544.50 | 3.633.59 | 99.59 | 50 |
| HbF FITCHbF TC | 4.544.49 | 3.633.58 | 99.63 | 50 |
| HbF R-PEHbF TC | 4.504.49 | 3.593.58 | 99.70 | 50 |
Summary of Correlations on EPICS-XL Flow Cytometer Prepared Samples
| Comparisons | Mean %Positive | ConfidenceInterval (95%) | r2 Value | n |
|---|---|---|---|---|
| HbF FITCKB | 4.224.40 | 3.383.52 | 98.48 | 50 |
| HbF R-PEKB | 4.244.40 | 3.403.52 | 98.41 | 50 |
| HbF TCKB | 4.204.40 | 3.363.52 | 97.96 | 50 |
| HbF FITCHbF R-PE | 4.224.24 | 3.383.40 | 99.61 | 50 |
| HbF FITCHbF TC | 4.224.20 | 3.383.36 | 99.54 | 50 |
| HbF R-PEHbF TC | 4.244.20 | 3.403.36 | 99.67 | 50 |
In the following linear regression analyses, the correlations of the Caltag Fetal Hemoglobin test and KB test are presented separately for each study site with prepared and patient samples identified within each site. However, prepared samples analyzed in study site #1 are as indicated in the above tables.
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| Site 1HAF FITC | Patient Samples | FACscan Flow Cytometer | |||
|---|---|---|---|---|---|
| procedure | mean %positive | ConfidenceInterval (95%)------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | r 2value | ന | |
| HbF FITCKB Method | 0.510.51 | 0.040.03 | 96.80 | 30 | |
| HbF R-PE | Patient Samples | ||||
| procedure | positive | mean % ConfidenceInterval (95%) | r2value | റ | |
| HbF R-PEKB Method | 0.500.51 | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------0.050.03 | 96.84 | 30 | |
| HPF TCprocedure | Patient Samplesmean %positive | ConfidenceInterval (95%) | r2value | n | |
| HbF TCKB Method | 0.470.51 | ==============================================================================================================================================================================0.050.03 | 97.50 30 | ||
| Site 2 | |||||
| HbF FITC | Patient Samples | EPICS-XL Flow Cytometer | and and the comments of the comments of the comments of | ||
| procedure | mean %positive | ConfidenceInterval (95%) | r2value | n | |
| HbF FITCKB Method | 0.220.20 | +============================================================================================================================================================================0.070.05 | 98.34 | 38 | |
| HPF FITC | Prepared Samples | EPICS-XL Flow Cytometer | |||
| procedure | mean %positive | ConfidenceInterval (95%) | 12value | n | |
| HBF FITCKB Method | 1.521.61 | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------1.041 . 1 1 | 85.50 15 | ||
| . Site 3HPF R-PE | Patient Samples | EPICS-XL Flow Cytometer | |||
| procedure | mean %positive | ConfidenceInterval (95%) | r2value | n | |
| HbF R-PE | 0.08 | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------9.43 | 64.00 | 13 | |
| KB Method | 0.11 | 0.01 | ﺎﻧ | ||
| HbF R-PE | Prepared Samples | EPICS-XL Flow Cytometer | |||
| procedure | mean %positive | ConfidenceInterval (95%) | r2value | រា | |
| HbF R-PEKB Method | 1.381.40 | ==============================================================================================================================================================================0.930.81 | 84.01 | 15 |
.
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BIBLIOGRAPHY
- Freedman J., Lazarus A.H., Applications of flow cytometry in transfusion medicine, Transfusion 1. Medicine Reviews 9:87-109, 1995.
- Davis B. H., Flow Cytometric Analysis of Red Blood Cells in Clinical Flow Cytometry: Principles and 2. Application, pp 373-387, Williams & Wilkins, 1993.
- Sebring E.S., Polesky H.F., Fetomaternal hemorrhage: insk factors, ume of occurrence and 3. clinical effects, Transfusion 30:344-357, 1990.
- Kleihauer E., Braun H., Betke K., Demonstration of fetal hemoglobin in erythrocyces of a blood smear. 4. Klin. Wochenschr. 35:637-638, 1957.
- Emery C.L., Morway L.F., Chung-Park M. et. al., The Kleihauer-Betke Test, Clinical utility, న్. indication, and correlation in patients with placental abruption and cocaine use, Arch. Pathol. Lab. Med. 119:1032-1037, 1995.
- Towery R., English T.P., Wisner D., Evaluation of pregnant women after blunt injury, J. Trauma 6. 35:731-736, 1993.
- Corsetti J.P., Cox C., Leary J.F. et. al., Comparison of quantitative acid-elution technique and flow cytometry for 7. detecting fetal maternal hemorrhage, Ann. Clin. Lab Sci., 17:197-206. 1987.
- Nance S.J., Nelson J.M., Arnot P.A., Quantiation of fetal-maternal hemorrhage by flow cytomerry, Am. J. Clin. 8. Path. 91:288-292, 1989.
-
- Nance S.J., Garraty G., Application of flow cytometry to immunohematology, J. Immunol. Meth. 101:127-131. 1987.
-
- Medaris A.L., Hensleigh P.A., Parks D.R. et. al., Detection of fetal erythrocytes in maternal blood post partum with the fluorescence-activated cell sorter, Am. J. Obstet. Gynecol. 148(3):290-295, 1984.
- Thorne S.J., Thein S.L., Sampierro M. et. al., Immunochemical estimation of hemoglobin types in red blood cells 11. by FACS analysis, Brit. J. Hemat. 87:125-132, 1994.
- Davis B.H., Olsen S., Bigelow N.C. et. al., Detection of fetal red cells in fetomaternal hemorrhage using an ani-12. hemoglobin F monoclonal antibody by flow cytometry, Transfusion 38:749-756,1998.
- Stamatoyannopoulos G., Nienhuis A.W., Hemoglobin switching, in The Molecular Basis of Blood Diseases, pp. 67-13. 105. Saunders & Co., Philadelphia, 1987.
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- Nicholson J.K.A., Green T.A. and Collaborative Laboratories, Selection of anticoagulants for Ivmphocyte immunophenotyping. J. Immunol, Methods 165:31-35. 1993.
-
- Brown M.C., Hoffman R.A., Kirchanski S., Controls for flow cytometers in hematology and cellular immunology, Ann. N.Y. Acad. Sci. 468:93-103, 1986.
-
- Durrand R.E., Calibration of flow cytometer detector systems, Cytometry 2:192-193, 1981.
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Image /page/10/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized caduceus symbol, which is a staff with two snakes coiled around it, representing medicine and healing. The symbol is surrounded by the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" in a circular arrangement. The text is in all capital letters and is evenly spaced around the symbol.
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
SEP 1 7 1999
Caltag Laboratories c/o David C. Bishop, Ph.D. 605 Dilworth Road Downingtown, Pennsylvania 19335
Re: K990641 Trade Name: Caltag Fetal Hemoglobin Test Regulatory Class: II Product Code: GHQ Dated: July 13, 1999 Received: July 14, 1999
Dear Dr. Bishop:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we 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). 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 either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
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Page 2
Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770) 488-7655.
This letter will allow you to begin marketing your device as described in your 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 Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled. "Misbranding by reference to premarket notification"(21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".
Sincerely yours.
Steven Butman
Steven I. Gutman, M.D. M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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| Comments of the consisted on any and the consisted to the contribution of the contribution of the contribution of the contribution of the contribution of the contribution of | |
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510(k) Number (if known): _ K 990641
Ocvice Name:_CALIAG_FETAL HEMOGGOON_TEST
Indications For Use:
The Caltag Fetal Hemoglobin Test, containing either FITC, R-PE or TRI-COLOR® The Cattag Petal Hemoglobin Toot, Contractor Coating Cobin F), is intended for confugation followed by enumeration of fetal red blood cells. Fetal red cells are identified by the presence of feal hemoglobin by a flow cytometric method. Fetal cells, when found in the maternal circulation, may be an indication of fetal or maternal Cells, when round in the nateromplications. The hemorrhage of Rh+ fetal blood into trauna of various obsited complex of sensitizing Rh antibodies in the RIF materilar biood may readle in the edministration to the mother of Rh mother. Sellsluzation may or proveneed of a The Caltag Fetal Hemoglobin Test may millianc globanii (ruirg) soon all incompatible fetal-maternal hemorrhage and be used as an all in detecting "immunoprophylaxis with Rh immune globulin.
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CORH, Office of Device Evaluation (ODE)
(Division Sign-Off)
Division of Clinical Laboratory Devices K990641
510(k) Number
Prescription Use
(Per 21 CFR 801.109)
OR
Over-The-Counter Use_
(Optional Format 1-2-96)
§ 864.7455 Fetal hemoglobin assay.
(a)
Identification. A fetal hemoglobin assay is a device that is used to determine the presence and distribution of fetal hemoglobin (hemoglobin F) in red cells or to measure the amount of fetal hemoglobin present. The assay may be used to detect fetal red cells in the maternal circulation or to detect the elevated levels of fetal hemoglobin exhibited in cases of hemoglobin abnormalities such as thalassemia (a hereditary hemolytic anemia characterized by a decreased synthesis of one or more types of hemoglobin polypeptide chains). The hemoglobin determination may be made by methods such as electrophoresis, alkali denaturation, column chromatography, or radial immunodiffusion.(b)
Classification. Class II (special controls). A fetal hemoglobin stain intended for use with a fetal hemoglobin assay is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 864.9.