K014030 · DiaSorin, Inc. · MRG · Mar 26, 2002 · Clinical Chemistry
Device Facts
Record ID
K014030
Device Name
1,25-DIHYDROXYVITAMIN D125I RIA
Applicant
DiaSorin, Inc.
Product Code
MRG · Clinical Chemistry
Decision Date
Mar 26, 2002
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 862.1825
Device Class
Class 2
Indications for Use
The 1,25-Dihydroxyvitamin D 1251 RIA is a competitive equilibrium radioimmunoassay intended for the quantitative determination of 1,25-dihydroxyvitamin D (1,25-(OH)2-D) in human serum or EDTA plasma to be used to assess 1,25-(OH)2-D deficiency associated with renal disease. Since hydroxylation of circulating 25-hydroxyvitamin D to the biologically active form 1,25-(OH)2-D occurs in the kidney, renal disease may result in reduced levels of 1,25-(OH)2-D and compromised calcium metabolic homeostasis. Assay results should be used in conjunction with other clinical and laboratory data to assist the clinician in making individual patient management decisions in adult populations.
Device Story
Competitive equilibrium radioimmunoassay (RIA) for quantitative determination of 1,25-dihydroxyvitamin D in human serum or EDTA plasma. Procedure: sample extraction with acetonitrile to release metabolites from binding proteins and remove lipids; column chromatography on C18OH silica cartridges for purification. Treated samples incubated with rabbit anti-1,25-(OH)2 vitamin D antibody and 125I-radiolabeled tracer; bound/unbound separation via goat anti-rabbit polyethylene glycol precipitating complex. Centrifugation yields precipitate; radioactivity measured. Output: concentration in pg/mL derived from standard curve. Used in clinical laboratories by technicians. Results assist clinicians in managing patients with renal disease and compromised calcium homeostasis.
Clinical Evidence
Clinical trial conducted at three laboratories with 123 healthy donors and 87 ESRD patients. Established reference ranges: 19.8-68.0 pg/mL (normals) vs 1.6-17.3 pg/mL (ESRD). Precision evaluated via ANOVA across 16 assays over 110 days; total %CV ranged from 11.6% to 16.2% for low, mid, and high concentration samples. Fresh vs frozen sample equivalency confirmed via ANOVA (p-values 0.49 and 0.29).
Indicated for adult patients to assess 1,25-dihydroxyvitamin D deficiency associated with renal disease using human serum or EDTA plasma.
Regulatory Classification
Identification
A vitamin D test system is a device intended for use in clinical laboratories for the quantitative determination of 25-hydroxyvitamin D (25-OH-D) and other hydroxylated metabolites of vitamin D in serum or plasma to be used in the assessment of vitamin D sufficiency.
Special Controls
*Classification.* Class II (special controls). Vitamin D test systems must comply with the following special controls:(1) Labeling in conformance with 21 CFR 809.10 and
(2) Compliance with existing standards of the National Committee on Clinical Laboratory Standards.
Predicate Devices
DiaSorin 25-Hydroxyvitamin D 1251 RIA
Submission Summary (Full Text)
{0}------------------------------------------------
K014030
#### APPENDIX E
As required by 21 CFR 807.3, a summary of the 510(k) safety and effectiveness information contained in this submission is provided as Appendix E.
## 510(k) SUMMARY
SUBMITTED BY:
Diana Clive DiaSorin, Inc. 1951 Northwestern Ave. P.O. Box 285 Stillwater, MN 55082-0285 (651) 351-5582 voice (651) 351-5669 fax November 30, 2001
This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92.
NAME OF DEVICE: Trade Name:
1,25-Dihydroxyvitamin D 1251 RIA
Common Names/Descriptions:
the the Immunoassay for quantitative determination of 1,25 dihydroxyvitamin D (1,25-(OH)2-D)
Classification Name:
Vitamin D test system
PREDICATE DEVICE:
DiaSorin 25-Hydroxyvitamin D 1251 RIA
The 1,25-Dihydroxyvitamin D 1251 RIA assay is a competitive INTENDED USE: equilibrium radioimmunoassay intended for the quantitative determination of 1,25 dihydroxyvitamin D (1,25-(OH)2-D) in human serum or EDTA plasma to be used to assess 1,25-(OH)2-D deficiency associated with renal disease. Assay results should be used in conjunction with other clinical and laboratory data to assist the clinician in making individual patient management decisions in adult populations.
DEVICE DESCRIPTION: The 1,25-Dihydroxyvitamin D 1251 RIA is a competitive radioimmunoassay intended for the quantitative determination of 1,25 Dihydroxyvitamin D (1,25-(OH)2-D) in human serum or EDTA plasma. The assay consists of a two-step procedure. Serum or plasma patient samples as well as standards and kit controls are first extracted with acetonitrile to free the 1,25-(OH)2 vitamin D2 and D3 from their vitamin D binding protein, and remove lipids that might interfere with the assay. The metabolites are then extracted by column chromatography on C18OH silica cartridges using a series of organic solvent washes. Following the extraction, the treated samples are assayed using a
{1}------------------------------------------------
competitive radioimmunassay procedure. The primary antibody (rabbit anti-1,25-(OH)2 vitamin D) is highly specific for both 1,25(OH)2 vitamin D3 and 1,25(OH)2.vitamin D2. Vitamin D) is inghty specific for both 1,25(011)2 (011)2 vitamin D tracer Daring the binding sites on the primary antibody. Separation of bound and unbound vitamin D2 or D3 is accomplished using a goat anti-rabbit (GAR) polyethylene glycol precipitating complex. After an incubation and centrifugation, sample precipitates are proofitaing complex. The amount of radioactivity in the precipitate is inversely proportional to the concentration of 1,25-(OH)2 vitamin D in the sample. Values are proportional to the coma standard curve of known calibrators and expressed as pg/ml.
| Feature | 25-OH-D | 1,25-(OH)2-D |
|----------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Intended Use | FOR IN VITRO DIAGNOSTIC USE.<br>This kit is intended for the quantitative<br>determination of 25-hydroxyvitamin D<br>(25-OH-D) and other hydroxylated<br>vitamin D metabolites in human serum<br>or plasma to be used in the assessment<br>of vitamin D sufficiency. Assay<br>results should be used in conjunction<br>with other clinical and laboratory data<br>to assist the clinician in making<br>individual patient management<br>decisions in an adult population. | FOR IN VITRO DIAGNOSTIC USE.<br>This kit is intended for the quantitative<br>determination of 1,25-dihydroxy-<br>vitamin D (1,25-(OH)2-D) in human<br>serum or EDTA plasma to be used to<br>assess 1,25-(OH)2-D deficiency<br>associated with renal disease. Assay<br>results should be used in conjunction<br>with other clinical and laboratory data<br>to assist the clinician in making<br>individual patient management<br>decisions in adult populations. |
| Assay Type | RIA | RIA |
| Acetonitrile<br>Extraction | For isolation of 25-(OH)-D | For isolation of 1,25-(OH)2-D |
| Antiserum | Polyclonal specific for 25-(OH)-D2/D3 | Polyclonal specific for 1,25-(OH)2-D2/D3 |
| Tracer | 125I radiolabeled 25-(OH)-D analog | 125I radiolabeled 1,25-(OH)2-D3 analog |
| Precipitating<br>Complex | 20 minute incubation at 20-25° C with<br>second antibody precipitating complex | 20 minute incubation at 20-25° C with<br>second antibody precipitating complex |
| Kit Controls | Two levels, human serum based,<br>extracted identical to standards and<br>patient samples. | Two levels, human serum based,<br>extracted identical to standards and<br>patient samples. |
| Standards | Five levels, human serum based,<br>extracted identical to controls and<br>patient samples. | Five levels, human serum based,<br>extracted identical to controls and<br>patient samples. |
# TECHNOLOGICAL COMPARISON TO PREDICATE:
PERFORMANCE DATA: A clinical trial was conducted at three independent clinical laboratories. Serum values for 1,25(OH)2-vitamin D were collected from two distinct populations: apparently healthy normal donors, and patients with end-stage renal disease (ESRD). Reference ranges established in the trial are summarized below.
{2}------------------------------------------------
| All Sites | 1,25(OH)2D (pg/mL) | | | |
|------------|--------------------|------|------|-----------|
| Population | n | Mean | 2 SD | Range |
| Normals | 123 | 43.9 | 24.1 | 19.8-68.0 |
| ESRD's | 87 | | | 1.6-17.3 |
The equivalency of assay samples as either fresh serum or serum that has been frozen and The equivalely of about bangles mory table with 95% ANOVA determined P-values is presented below.
| | Normals | | ESRD's | |
|-------|---------|-------|--------|-------|
| | Frozen | Fresh | Frozen | Fresh |
| N | 72 | 51 | 70 | 17 |
| Mean | 43.2 | 44.8 | 6.1 | 5.3 |
| ANOVA | 0.49 | | 0.29 | |
Reproducibility was established both at DiaSorin and during the clinical trial. Three human serum-based samples with 1,25-(OH)2-D concentrations distributed across the numan berain based calliples with 5 assay days at DiaSorin, spanning more than 60 Multiple technicians, as well as multiple lot numbers for all operating days. operaing were included. The combined results were evaluated by analysis of variance (ANOVA) and are summarized in the following table.
| | | | Within-run | | Between Day | | Total | |
|--------|----|-----------------|------------|-------|-------------|-------|-------|-------|
| Sample | n | Mean<br>(pg/mL) | S.D. | %C.V. | S.D. | %C.V. | S.D. | %C.V. |
| Low | 25 | 25.8 | 1.76 | 6.8 | 3.8 | 14.6 | 4.0 | 15.3 |
| Mid | 25 | 41.3 | 3.16 | 7.7 | 4.6 | 11.1 | 5.1 | 12.3 |
| High | 25 | 105.2 | 11.86 | 11.3 | 11.8 | 11.2 | 14.4 | 13.7 |
{3}------------------------------------------------
These identical human serum-based controls were assayed during a clinical trial conducted at three different laboratories, over 16 different assays, spanning more than 110 days. The combined results from all three sites are summarized below.
| Sample | n | Mean<br>(pg/mL) | S.D. | %CV |
|--------|----|-----------------|------|------|
| Low | 16 | 24.2 | 3.9 | 16.2 |
| Mid | 16 | 41.0 | 5.8 | 14.1 |
| High | 16 | 97.7 | 11.3 | 11.6 |
Similarly, kit controls included with each kit were included in each of the 16 assays The following table above, as prescribed in the package insert instructions. summarizes the precision of the controls over the course of the clinical trial.
| | | Site A | Site B | Site C | Total |
|---------------|------|--------|--------|--------|-------|
| Kit Control 1 | n | 7 | 4 | 8 | 19 |
| | Mean | 24.7 | 27.2 | 25.5 | 25.6 |
| | SD | 3.1 | 3.3 | 4.0 | 3.5 |
| | %CV | 12.5 | 12.2 | 15.8 | 13.7 |
| Kit Control 2 | n | 7 | 4 | 7 | 18 |
| | Mean | 66.2 | 59.9 | 67.2 | 65.2 |
| | SD | 5.1 | 4.2 | 11.1 | 8.1 |
| | %CV | 7.8 | 7.1 | 16.6 | 12.4 |
The data collected during the clinical trial described above fully CONCLUSION: substantiates the intended use of the 1,25-Dihydroxyvitamin D 1251 RIA. Reference ranges established for both a healthy population and one with end stage renal disease are fully distinct. This indicates that the DiaSorin 1,25-Dihydroxvitamin D 131 RIA can effectively discriminate between the two populations based on 1,25-(OH)2-D serum values. Assay results can be used to assess 1,25-(OH)2-D deficiency associated with renal disease.
{4}------------------------------------------------
Image /page/4/Picture/2 description: The image shows the logo for the Department of Health & Human Services. The logo consists of a circular border with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" arranged around the perimeter. Inside the circle is a stylized symbol featuring three abstract shapes that resemble a person or a bird in flight. The shapes are layered on top of each other, creating a sense of movement and depth.
# MAR 2 6 2002
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
Mr. David M. Ikeda Manager, Regulatory Affairs and Quality Systems DiaSorin Inc. 1990 Industrial Blvd. P.O. Box 285 Stillwater, MN 55082-0285
Re: k014030
Trade/Device Name: 1,25-Dihydroxyvitamin D 1251 RIA Kit Regulation Number: 21 CFR 862.1825 Regulation Name: Vitamin D test system Regulatory Class: Class II Product Code: MRG Dated: February 18, 2002 Received: February 20, 2002
#### Dear Mr. Ikeda:
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 either class II (Special Controls) or class III (PMA), 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 898. 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 Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
{5}------------------------------------------------
Page 2 -
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 1 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" (21CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers International and Consumer 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
{6}------------------------------------------------
## INDICATIONS FOR USE
510(k) Number (if known):
Device Name:
1,25-Dihydroxyvitamin D 1251 RIA Kit
K014030
Indications For Use:
The 1,25-Dihydroxyvitamin D 1251 RIA is a competitive equilibrium radioimmunoassay intended for the quantitative determination of 1,25-dihydroxyvitamin D (1,25-(OH)2-D) in human serum or EDTA plasma to be used to assess 1,25-(OH)2-D deficiency associated with renal disease. Since hydroxylation of circulating 25-hydroxyvitamin D to the biologically active form 1,25-(OH)2-D occurs in the kidney, renal disease may result in reduced levels of 1,25-(OH)2-D and compromised calcium metabolic homeostasis. Assay results should be used in conjunction with other clinical and laboratory data to assist the clinician in making individual patient management decisions in adult populations.
### (PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Division Sign-Off
Carol C. Benson for Jean Cooper
vision of Clinical Laboratory D 510fki Number Prescription Use: the-Counter Use: (Per 21 CFR 801.109)
Predicate graph will load when search results are available.
Embedding visualization will load when search results are available.
PDF viewer will load when search results are available.
Loading panels...
Select an item from Submissions
Click any panel, subpart, regulation, product code, or device to see details here.
Section Matches
Results will appear here.
Product Code Matches
Results will appear here.
Special Control Matches
Results will appear here.
Loading collections...
Loading
My Alerts
You will receive email notifications based on the filters and frequency you set for each alert.
Sort by:
Create Alert
Search Filters
Agent Token
Create a read-only bearer token for Claude, ChatGPT, or other agents that can call HTTP APIs.
Copy this now. It will not be shown again.
Connected apps
Apps you authorized through browser sign-in. Disconnecting revokes their access immediately.
Learn the FDA Browser
Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.