Helicobacter Test INFAI - summary of medicine characteristics

1. NAME OF THE MEDICINAL PRODUCT

Helicobacter Test INFAI 75 mg powder for oral solution

2. QUALITATIVE AND QUANTITATIVE COMPOSITION

One jar contains 75 mg of 13C-urea powder.

For the full list of excipients, see section 6.1.

3. PHARMACEUTICAL FORM

White, crystalline powder for oral solution.

4. CLINICAL PARTICULARS4.1 Therapeutic indications

Helicobacter Test INFAI may be used for in vivo diagnosis of gastroduodenal Helicobacter pylori infection in:

• – adults,

• – adolescents, who are likely to have peptic ulcer disease.

This medicinal product is for diagnostic use only.

4.2 Posology and method of administration

This medicinal product should be administered by a healthcare professional and under appropriate medical supervision.

Posology

Helicobacter Test INFAI is a breath test for single administration. Patients from the age of 12 must take the contents of 1 jar with 75 mg.

Method of administration

For performance of the test, 200 ml 100 % orange juice or 1 g citric acid in 200 ml water for patients from the age of 12 and older (as a pre-administered test meal), as well as tap water (for dissolving the 13C-urea powder) are necessary.

The patient must have fasted for over 6 hours, preferably overnight. The test procedure takes approximately 40 minutes.

In case it is necessary to repeat the test procedure, this should not be done until the following day.

The suppression of Helicobacter pylori might give false negative results. Therefore the test shall be used after at least four weeks without systemic antibacterial therapy and two weeks after last dose of acid antisecretory agents. Both might interfere with the Helicobacter pylori status. This is especially important after Helicobacter eradication therapy.

It is important to follow the instructions for use adequately (see section 6.6), otherwise the reliability of the outcome will become questionable.

4.3 Contraindications

The test must not be used in patients with documented or suspected gastric infection or atrophic gastritis, which might interfere with the urea breath test (see section 4.2).

4.4 Special warnings and precautions for use

A positive test alone does not constitute indication for eradication therapy. Differential diagnosis with invasive endoscopic methods might be indicated in order to examine the presence of any other complicating conditions, e.g. ulcer, autoimmune gastritis and malignancies.

There is insufficient data on the diagnostic liability of the Helicobacter Test INFAI to recommend its use in patients with gastrectomy.

For children from the age of 3, Helicobacter Test INFAI for children aged 3 to 11 is available.

In individual cases of A-gastritis (atrophic gastritis) the breath test may have false positive results; other tests may be required to confirm the Helicobacter pylori status.

If the patient vomits during the test procedure, necessitating the repetition of the test, this should be done in fasted condition and not before the following day (see section 4.2).

4.5 Interaction with other medicinal products and other forms of interaction

Helicobacter Test INFAI will be affected by all treatments interfering with Helicobacter pylori status or urease activity.

4.6 Fertility, pregnancy and lactation

It is not expected that the test procedure may be harmful during pregnancy or lactation.

It is recommended to take notice of the product information of eradication therapy products for their use during pregnancy and lactation.

4.7 Effects on ability to drive and use machines

Helicobacter Test INFAI has no influence on the ability to drive and use machines.

4.8 Undesirable effects

None known.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the national reporting system listed in

4.9 Overdose

Due to the fact that only 75 mg of 13C-urea is delivered, an overdose is not expected.

5. PHARMACOLOGICAL PROPERTIES5.1 Pharmacodynamic properties

Pharmacotherapeutic group: Other diagnostic agents, ATC code: VO4CX

For the amount of 75 mg 13C-urea, which is administered per unit in the course of the breath test, no pharmacodynamic activity is described.

After oral ingestion the labelled urea reaches the gastric mucosa. In the presence of Helicobacter pylori the 13C-urea is metabolised by the enzyme urease of Helicobacter pylori.

2H2N(13CO)NH2 + 2H2O  Enzyme urease >  4NH3 + 213CO2

The carbon dioxide diffuses into the blood vessels. From there it is transported as bicarbonate into the lung and liberated as 13CO2 with the exhaled air.

In the presence of bacterial urease the ratio of the 13C/12C-carbon isotopes is significantly changed. The portion of 13CO2 in the breath samples is determined by isotope-ratio-mass-spectrometry (IRMS) and stated as an absolute difference (A8-value) between the 00-minute- and the 30-minute-values.

Urease is produced in the stomach only by Helicobacter pylori. Other urease producing bacteria were seldom found in the gastric flora.

The cut off point for discriminating Helicobacter pylori -negative and positive patients is determined to be A8-value of 4 %o, which means that an increase of the A8-value by more than 4 %o indicates an infection. In comparison to bioptic diagnostics of an infection with Helicobacter pylori , the breath test achieved in clinical trials on 457 patients, a sensitivity in the range of 96.5 % to 97.9 % [95 %-CI: 94.05 %-99.72 %], and a specificity range from 96.7 % to 100 %. [95 %-CI: 94.17 %-103.63 %], whereas in clinical trials on 93 adolescents from the age 12–17, a sensitivity of 97.7 % [90 %-CI: 91.3 %], and a specificity of 96.0 % [90 %-CI: 89.7 %] were achieved.

In the absence of bacterial urease, the whole amount of the administered urea after absorption from the gastrointestinal tract will be metabolised like the endogenous urea. Ammonia which is produced as described above by the bacterial hydrolysis is included into the metabolism as NH4+.

5.2 Pharmacokinetic properties

The orally applied 13C-urea is metabolised to carbon dioxide and ammonia or is integrated into the body’s own urea cycle. Any increase in 13CO2 will be measured by isotopic analysis.

Absorption and distribution of 13CO2 is faster than the urease reaction. Therefore, the rate-limiting step in the whole process is the cleavage of 13C-urea by Helicobacter's u­rease.

Only in Helicobacter pylori -positive patients does the administration of 75 mg labelled urea lead to a significant increase of 13CO2 in the breath sample within the first 30 minutes.

5.3 Preclinical safety data

No concerns in relation to the clinical use of the product.

6. PHARMACEUTICAL PARTICULARS6.1 List of excipients

None.

6.2 Incompatibilities

Not applicable.

• 6.3 Shelf-life 3 years

6.4 Special precautions for storage

Do not store above 25 °C.

6.5 Nature and contents of container

A test set contains the following parts:

6.6 Special precautions for disposal and other handling

• 1. The test is to be performed in the presence of a qualified person.

• 2. Each patient should be documented according to the provided data sheet. It is recommended to perform the test with the patient being in a resting position.

• 3. The test starts with the collection of samples for the determination of baseline-value (00-minute-value):

• • Take the straw and the two sample tubes with the label

“Sampling time: 00-minute-value” out of the test set.

• • Remove the stopper from one of the sample tubes, unwrap the straw and place the straw

into the container.

• • Now the patient breathes gently through the straw until the inner surface of the sample tube steams up.
• • By continuously breathing the patient must pull out the straw and immediately close the

sample tube with its stopper.

(If the sample tube remains open for more than 30 seconds, the test result might be falsified.)

• • Hold the sample tube upright and stick the bar-code label marked “00-minute-value”

round the sample tube, so that the lines of the bar-code are horizontal.

• 4. Fill up the second sample tube (Label “Sampling time: 00-minute-value”) with breath by following the same procedure.

• 5. Now 200 ml of 100 % orange juice or 1 g citric acid in 200 ml water must be drunk by the patient without delay.

• 6. Now the preparation of the test solution follows:

• • The jar labelled “13C-urea powder” is taken from the test set, opened, and filled up to

three quarters of its volume with tap water.

• • Close the jar and shake it carefully until all the powder is dissolved. Pour the contents

into a drinking glass.

• • Fill the 13C-urea jar to the brim with water for a second and third time and add these

contents to the drinking glass (total volume of tap water should be approximately 30 ml).

• 7. This test solution must now be drunk immediately by the patient, and the time of application must be noted.

• 8. Thirty minutes after administration of the test solution (point 7), collect the 30-minute-value samples in the two containers which are left in the test package (Label “Sampling time: 30-minute-value”), as described under steps 3 to 4. Use the bar-code labels marked “30-minute-value” for these samples.

• 9. Put the relevant bar-code label on the data sheet for patient documentation. Finally seal the package with the sticker.

• 10. The sample tubes have to be sent in the original packaging, for analysis, to a qualified laboratory.

Analysis of breath samples and testing specification for laboratories

The breath samples, collected in 10 ml glass- or plastic sample tubes, are analysed by isotope ratio mass spectrometry (IRMS).

The analysis of the 13C/12C-ratio in carbon dioxide of breath is an integrated part of the diagnostic test Helicobacter Test INFAI. The accuracy of the test strongly depends on the quality of the breath analysis. The specification of breath analysis parameters like linearity, stability (reference gas precision), and precision of measurement are fundamental for the accuracy of the system.

It has to be ensured that the analysis is carried out by a qualified laboratory. The method validated in the application is as follows:

• • Sample preparation for (IRMS)

To determine the 13C/12C-ratio of carbon dioxide in breath by mass spectrometric analysis the carbon dioxide must be separated from the breath and introduced into the mass spectrometer. The automatic preparation system for isotope mass spectrometers which is dedicated for breath test analysis is based on a gas-chromatographic continuous flow separation technique.

Water is removed from the sample by means of a Nafion water trap or the gas-chromatographic preparation system that separates the individual gases in a gas chromatographic column with Helium as eluent. Passing the column the separated gas species of breath are detected by an ionisation detector. The fraction of carbon dioxide gas, identified by its characteristic retention time, is introduced into mass spectrometer.

• • Mass spectrometric analysis

To analyse the separated carbon dioxide sample gas its molecules must be ionised, formed into a beam, accelerated by an electric field, deflected in a magnetic field, and finally detected. These five processes take place in the analyser of a mass spectrometer, which consists of three separate sections: the source, flight tube, and collector. Ionisation, beam formation and acceleration all occur in the source, magnetic deflection takes place in the flight tube and detection takes place in the collector.

• • Sample inlet

For introduction of the carbon dioxide into the analyser many sample inlet systems are available. For breath test analysis the individual balancing of the carbon dioxide of the sample to a reference standard gas is essential. This ensures the high accuracy of this system, as calculation of the isotopic content in carbon dioxide is done with respect to an independent standard.

• • Specifications for determining 13C/12C-ratios

The breath test concept relies on the administration of a specifically 13C-labelled urea whose metabolite utilisation is monitored by measuring 13CO2 in the expired breath gas.

The mass spectrometer must be capable of:

• •

The principal tests to verify the specifications are linearity, stability (reference gas precision), and precision of measurement.

• •     All mass spectrometers for breath analysis must comply with the following specifications:

Helicobacter pylori infection is present if the difference in 13C/12C of baseline-value and 30-minute-value exceeds 4.0 %o.

Alternatively, any other suitable-validated method may be used, carried out by any objectively qualified laboratory.

7. MARKETING AUTHORISATION HOLDER

INFAI GmbH

Riehler Str. 36

D-50668 Köln

Germany

8. MARKETING AUTHORISATION NUMBER

EU/1/97/045/001

9. DATE OF FIRST AUTHORISATION/RENEWAL OF THE AUTHORISATION

Date of first authorisation: 14 August 1997

Date of latest renewal: 14 August 2007