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Category Active immunizing agent.

      Meningococcal Polysaccharide Vaccine is a freezedried preparation of one or more purified capsular polysaccharides obtained from one or more suitable strains of Neisseria meningitidis group A, group C, group Y and group W 135 that are capable of consistently producing polysaccharides.

      N. meningitidis group A polysaccharide consists of partly O-acetylated repeating units of N-acetylmannosamine, linked with 1α → 6 phosphodiester bonds.

      N. meningitidis group C polysaccharide consists of partly O-acetylated repeating units of sialic acid, linked with 2α → 9 glycosidic bonds.

      N. meningitidis group Y polysaccharide consists of partly O-acetylated alternating units of sialic acid and D-glucose, linked with 2α → 6 and 1α → 4 glycosidic bonds.

      N. meningitidis group W135 polysaccharide consists of partly O-acetylated alternating units of sialic acid and D-galactose, linked with 2α → 6 and 1α → 4 glycosidic bonds.

      The polysaccharide component or components stated on the label together with calcium ions and residual moisture account for over 90 per cent of the weight of the preparation.

      The vaccine, reconstituted as stated on the label, complies with the requirements stated under Vaccines, with the following modifications.

Description The dried vaccine is a white or creamcoloured powder or pellet. When reconstituted, it becomes a clear colourless liquid.

Solubility Freely soluble in water.

Stability The reconstituted solution of freeze-dried vaccine should be stored at a temperature between 2º and 8º and used within 30 minutes, unless otherwise specified by the manufacturer. The solution should not be used if there is extraneous particulate matter and/or discoloration.

Strength available 50 μg of polysaccharide from each of the serogroup of meningococci represented in the vaccine per dose (0.5 ml).

Dose Subcutaneous, 0.5 ml.

Warning​

1. It may cause erythema, pain or induration at the injection site.

2. Headache, malaise, fatigue, lethargy, fever, chills, rash, coryza, and gastro-intestinal symptoms may occur.

          3. It should not be administered concomitantly with any vaccine containing whole-cell pertussis or wholecell typhoid antigens because of concerns related to combined endotoxin content.

4. If the vaccine is used in people receiving immunosuppressive therapy, the expected immune response may not be obtained.

Additional information

1. It is indicated in persons travelling to countries where the risk of infection is high.

2. It is not indicated for infants and children under two years of age except as short-term protection of infants at least 3 months of age against Group A.

3. It may be administered concurrently with other vaccines, using separate body sites, separate syringes, and the precautions that apply to each immunizing agent.

          4. Revaccination may be indicated for persons at high risk of infection, particularly children at high risk who were first immunized before they were 4 years of age; such children should be considered for revaccination after 2 or 3 years if they remain at high risk.

Expiration date When stored under the prescribed conditions, the expiration date is not later than 2 years from the date of the last satisfactory assay.

Labelling Complies with the “General Information for Biological Products”, p. 177. In addition the label on the container states (1) the number of micrograms of polysaccharide in each dose; (2) the total quantity of polysaccharide in the container; (3) the group or groups of polysaccharides A, C, Y, or W135 and, for multispecific vaccines, the quantity of each polysaccharide per dose.

Identification Identify by a suitable immunochemical method (Appendix 14.5) such as immuno-precipitation, ELISA or radio-immunoassay.

Molecular size Carry out the test as described in the “Size-exclusion Chromatography” (Appendix 3.6), applying a quantity of the vaccine containing about 2.5 mg of each polysaccharide in a volume of about 1.5 ml.

      The chromatographic procedure may be carried out using (a) a column (about 900 mm × 16 mm) packed with cross-linked agarose for chromatography for a divalent vaccine or cross-linked agarose for chromatography 1 for a tetravalent vaccine and (b) a solvent having an ionic strength of 0.2 molal and a pH of 7.0 to 7.5 as the mobile phase with a flow rate of approximately 20 ml per hour.

      Collect fractions of about 3 ml and determine the content of each polysaccharide by a suitable method.

      FOR A DIVALENT VACCINE (GROUP A + GROUP C ) The vaccine complies with the test if: 65 per cent of group A polysaccharide is eluted before distribution coefficient (K_D) of 0.50 is reached; 75 per cent of group C polysaccharide is eluted before K_D of 0.50 is reached.

      FOR A TETRAVALENT VACCINE (GROUP A + GROUP C + GROUP Y + GROUP W135 ) Apply a suitable immunochemical method (Appendix 14.5) to establish the elution pattern of the different polysaccharides.

      The vaccine complies with the test if K_D for the principal peak is:

– not more than 0.70 for group A and group C polysaccharide,

– not more than 0.57 for group Y polysaccharide,

– not more than 0.68 for group W135 polysaccharide.

Pyrogens Complies with the “Pyrogen Test” (Appendix 8.2), using a solution containing a quantity of the vaccine equivalent to 0.025 μg purified polysaccharide per ml for a monovalent vaccine; 0.050 μg of purified polysaccharide per ml for a divalent vaccine; 0.075 μg of purified polysaccharide per ml for a trivalent vaccine; 0.10 μg of purified polysaccharide per ml for a tetravalent vaccine and injecting 1.0 ml per kg of the rabbit’s weight.

Assay Carry out an assay of each polysaccharide present in the vaccine. 

      For a divalent vaccine (group A + group C), use measurement of phosphorus to determine the content of polysaccharide A and measurement of sialic acid to determine the content of polysaccharide C.

      To determine sialic acid, use as reference solution a 150 mg per litre solution of N-acetylneuraminic acid.

      For a tetravalent vaccine (group A + group C + group Y + group W135) a suitable immunochemical method (Appendix 14.5) is used with a reference preparation of purified polysaccharide for each group.

      The vaccine contains not less than 70 per cent and not more than 130 per cent of the quantity of each polysaccharide stated on the label.

      FOR PHOSPHORUS

      Test solution Use a volumetric flask with a suitable volume for preparation of a solution containing about 5 mg per ml of dry polysaccharide. Transfer the contents of a container quantitatively to the flask and dilute to volume with water. Dilute the solution so that the volume used in the test (1 ml) contains about 6 μg of phosphorus. Transfer 1.0 ml of the solution to a 10-ml ignition tube.

      Reference solutions Dissolve 0.2194 g of potassium dihydrogenphosphate in 500 ml of water to give a solution containing the equivalent of 0.1 mg of phosphorus per millilitre. Dilute 5.0 ml of the solution to 100.0 ml with water. Introduce 0.5 ml, 1.0 ml and 2.0 ml of the dilute solution into three ignition tubes.

      Prepare a blank solution using 2.0 ml of water in an ignition tube.

      To all the tubes add 0.2 ml of sulfuric acid and heat in an oil-bath at 120º for 1 hour and then at 160º until white fumes appear (about 1 hour). Add 0.1 ml of perchloric acid and heat at 160º until the solution is decolourized (about 90 minutes). Cool and add to each tube 4 ml of water and 4 ml of ammonium molybdate with ascorbic acid TS. Heat in a water-bath at 37º for 90 minutes and cool. Adjust the volume to 10.0 ml with water. The blue colour is stable for several hours.

      Measure the absorbance at 820 nm (Apppendix 2.2), using in the reference cell 2.0 ml of water that has been treated in the same manner. Draw a calibration curve with the absorbances of the three reference solutions as a function of the quantity of phosphorus in the solutions and read from the curve the quantity of phosphorus in the test solution.

      FOR SIALIC ACID

      Test solution Transfer quantitatively the contents of one or several containers to a volumetric flask of a suitable volume that will give a solution with a known concentration of about 250 μg per millilitre of polysaccharide and dilute to volume with water. Using a syringe, transfer 4.0 ml of this solution to a10-ml ultrafiltration cell suitable for the passage of molecules of relative molecular mass less than 50,000. Rinse the syringe twice with water and transfer the rinsings to the ultrafiltration cell. Carry out the ultrafiltration, with constant stirring, under nitrogen at a pressure of about 150 kPa (1125 Torr). Refill the cell with water each time the volume of liquid in it has decreased to 1 ml and continue until 200 ml has been filtered and the remaining volume in the cell is about 2 ml. Using a syringe, transfer this residual liquid to a 10-ml volumetric flask. Wash the cell with 3 quantities, each of 2 ml, of water, transfer the washings to the flask and dilute to 10.0 ml with water (test solution). In each of two test-tubes place 2.0 ml of the test solution.

      Reference solution Use a 0.015 per cent w/v solution of N-acetylneuraminic acid.

      Prepare two series of three test-tubes, place in the tubes of each series 0.5 ml, 1.0 ml and 1.5 ml, respectively, of the reference solution and adjust the volume in each tube to 2.0 ml with water.

      Prepare blank solutions using 2.0 ml of water in each of two test-tubes.

      To all the tubes add 5.0 ml of resorcinol with copper(II) sulfate TS. Heat at 105º for 15 minutes, cool in cold water and transfer the tubes to a bath of iced water. To each tube add 5 ml of 3-methyl-1-butanol and mix thoroughly. Place in the bath of iced water for 15 minutes. Centrifuge the tubes and keep them in the bath of iced water until the examination by absorption spectrophotometry. Measure the absorbance of each supernatant solution at 580 nm and 450 nm (Appendix 2.2), using 3-methyl-1-butanol as the blank. For each wavelength, calculate the absorbance as the mean of the values obtained with two identical solutions. Subtract the mean value for the blank solution from the mean values obtained for the other solutions.

      Draw a graph showing the difference between the absorbances at 580 nm and 450 nm of the reference solutions as a function of the content of N-acetylneruaminic acid and read from the graph the quantity of N-acetylneuraminic acid (sialic acid) in the test solution.