INgezim® COVID 19 CROM
R.50.CoV.K41

The INgezim® COVID 19 CROM test is a dual-recognition
immunochromatographic assay capable of detecting specific COVID-19 (SARSCoV-2) antibodies in serum and blood samples.
Application®

INgezim COVID 19 CROM qualitatively determines the total antibodies (IgG, IgA, and IgM) specific to SARS-CoV2 virus N in a single blood, serum, or plasma sample by using nucleoprotein (N protein) as an antigen for detectionof antibodies to the virus. This rapid, point-of-care test delivers results in only 10 minutes and can be performed
outside of the laboratory. The test is intended for use by healthcare professionals, not for self-diagnosis.

Technical Principles

T1

2

The test uses coloured latex microspheres that bind to theproteins of interest. The black particles are covalently boundto the full-length recombinant SARS-CoV-2 N protein (2),while the blue particles are bound to a control protein (1),indicating
thecorrect
developmentof
theimmunochromatography.

C

3

4

The membrane contains a test line (T), in which the SARSCoV-2 N protein (3) is immobilized, and a control line (C),formed by a specific monoclonal antibody (4) of the control
protein. SARS-CoV-2 antibodies present in the sample reactwith the black latex particles coated and thelatex/protein/antibody complex, migrate across the membrane,
and bind to the protein contained within the test line, resulting
in a coloured T line. If the sample has no SARS-CoV-2
antibodies, no colour will appear on the T line. The C line must
always appear blue or the test is invalid.

Validation Data
The product has been validated with collections of previously characterized sera.
DIAGNOSTIC SENSITIVITY AND SPECIFICITY
Diagnostic sensitivity was determined in two ways:
1. In comparison to the PCR technique (157 sera
extracted on different days after the first day ofsymptoms onset from patients tested positive byPCR)
A relative sensitivity of 72.6% was obtained with respect
to the PCR technique. The difference in the detection
target between the two techniques should be taken intoaccount. PCR detects the virus itself, while the®
INgezim
COVID 19 CROM assay detects theantibodies generated after infection. Antibodies takesome days/weeks to appear in detectable quantities
after infection while the virus is generally detectableearlier in the nasopharyngeal area.

Results in comparison with PCR®
INgezim COVIDPCR
19 CROMPOSITIVE
114
157
NEGATIVE
430

Results in comparison with serological tests®
INgezim COVID- Other tests
19 CROMPOSITIVE
286
315
NEGATIVE
2902. In comparison to other commercial serologicaltests (315 sera)
The relative sensitivity with respect to other commercial
ELISA kits is 90.7%.
To determine diagnostic specificity, 146 sera previously classified as: (1) sera from patients tested positive by
PCR and negative by serology, (2) sera from patients tested negative by PCR and negative by serology, or (3)sera from historically negative patients (blood donors prior to 2019) were analysed. Results showed 99.3%
specificity.

ANALYTICAL SENSITIVITY AND SPECIFICITY
Study of Analytical Sensitivity

Post-symptoms (%) on different days

To determine the ability of the assay to detect antibodies
during an infection, 153 human sera were tested,
extracted on different days after the first day symptoms
appeared. The table shows the data grouped by postsymptom periods and the percentage of positives
detected. In 68% of cases, the assay was able to detect
antibodies from day 11 after the onset of first symptoms,
and in 94.5% of cases from day 19.

94,55%
67,74%
52,94%

0-5

6-10

11-18

19-32

Study of Analytical Specificity
To determine the analytical specificity of the assay, samples were analysed from people affected by otherrespiratory coronaviruses (229E, NL63, OC43, and HKU1) and people with respiratory infections caused by otheragents, such as RSV, enteroviruses, Bordetella pertussis, Mycoplasma pneumoniae, Influenza A and B, andadenoviruses.
The results obtained indicate no cross-reactivity with antibodies specific to other coronaviruses or agents
related to human respiratory illnesses. As a result, the specificity was established higher than 99%.

Inmunología y Genética Aplicada, S.A.
(INGENASA)
Av. de la Institución Libre de Enseñanza, 39 - 8ªplanta 28037 MADRID
Tl (+34) 913 68 0501
email:ingenasa@ingenasa.com

PRODUCT MANUFACTURED BY INGENASA
IVD medical devices manufacturer licence:
7709-PSEXPIRATION

12 months
Keep at 4ºC-25ºC