[Title 21 CFR D]
[Code of Federal Regulations (annual edition) - April 1, 1996 Edition]
[Title 21 - FOOD AND DRUGS]
[Chapter I - FOOD AND DRUG ADMINISTRATION,]
[Subchapter F - BIOLOGICS]
[Part 620 - ADDITIONAL STANDARDS FOR BACTERIAL PRODUCTS]
[Subpart D - Cholera Vaccine]
[From the U.S. Government Publishing Office]




  21
  FOOD AND DRUGS
  7
  1996-04-01
  1996-04-01
  false
  Cholera Vaccine
  D
  Subpart D
  
    FOOD AND DRUGS
    FOOD AND DRUG ADMINISTRATION,
    BIOLOGICS
    ADDITIONAL STANDARDS FOR BACTERIAL PRODUCTS
  


                       Subpart D--Cholera Vaccine



Sec. 620.30   Cholera Vaccine.

    The proper name of this product shall be Cholera Vaccine, which 
shall consist of an aqueous preparation of equal parts of Ogawa and 
Inaba serotypes of killed Vibrio cholerae bacteria.
[41 FR 18295, May 3, 1976]



Sec. 620.31   Production.

    (a) Strains of bacteria. (1) A strain of Ogawa and a strain of Inaba 
serotypes of V. cholerae shall be used in the manufacture of the 
vaccine. Each serotype strain shall have been shown in controlled field 
studies to yield a vaccine no less potent than vaccines prepared from 
Ogawa strain 41 and Inaba strain 35A3 obtained from the Center for 
Biologics Evaluation and Research.
    (2) Antigenic integrity of the strains shall be verified by (i) the 
agglutination of living bacteria of each serotype by cholera O Group I 
antiserum; (ii) the agglutination of the Ogawa strain in monospecific 
Ogawa antiserum and of the Inaba strain in monospecific Inaba antiserum; 
and (iii) the absence of spontaneous agglutination of living bacteria of 
either strain in 0.85 percent sodium chloride solution during incubation 
for at least 5 hours at 37 deg. C.
    (b) Propagation of bacteria. The culture medium for the propagation 
strains shall not contain ingredients known to be capable of producing 
allergenic effects in human subjects. The harvested bacteria shall be 
free of extraneous bacteria, fungi, and yeasts as demonstrated by 
microscopic examination and cultural methods. Bacteria of the two 
serotypes shall be grown separately.
    (c) Bacterial content. (1) The number of bacteria in each separate 
bacterial harvest shall be determined by use of the U.S. Opacity 
Standard not later than 2 hours after harvest and before treatment with 
a preservative or other agent capable of altering opacity of the 
bacterial suspension.
    (2) The vaccine shall contain equal numbers of bacteria of the Ogawa 
and Inaba serotypes, and the total number shall not exceed 8  x  
109 bacteria per milliliter.
    (d) Nitrogen content. The total nitrogen content of the vaccine 
shall not exceed 0.3 milligram per milliliter for bacteria grown on 
solid medium or 1.0 milligram per milliliter if grown in liquid medium. 
In no instance shall the vaccine contain more than 0.07 milligram per 
milliliter of nitrogen precipitable by the addition of an equal volume 
of 10 percent trichloracetic acid.
    (e) Preservative. The vaccine shall contain a preservative.

[41 FR 18295, May 3, 1976, as amended at 49 FR 23834, June 8, 1984; 55 
FR 11013, Mar. 26, 1990]



Sec. 620.32   U.S. Standard preparations.

    The following U.S. Standard preparations shall be obtained from the 
Center for Biologics Evaluation and Research, Food and Drug 
Administration, for use as prescribed in this subpart:
    (a) Vaccine standard. The U.S. Standard Cholera Vaccine, Ogawa 
serotype, and U.S. Standard Cholera Vaccine, Inaba serotype, shall be 
reconstituted as directed for determining the potency of Cholera 
Vaccine.
    (b) Opacity standard. The U.S. Opacity Standard for use in 
estimating the bacterial content of the vaccine and of the challenge 
culture.
    (c) Seed culture. Seed cultures of V. cholerae, Inaba serotype, 
strain 35A3 and Ogawa serotype, strain 41, for preparation of vaccine 
challenge cultures for use in the vaccine potency test.

[41 FR 18295, May 3, 1976, as amended at 49 FR 23834, June 8, 1984; 55 
FR 11013, Mar. 26, 1990]



Sec. 620.33   Potency tests.

    Each lot of vaccine shall be subjected to two potency tests. One 
test shall determine the potency of the vaccine in comparison with the 
U.S. Standard

[[Page 79]]

Cholera Vaccine, Ogawa serotype, and the other test shall determine the 
potency of the vaccine in comparison with the U.S. Standard Cholera 
Vaccine, Inaba serotype. At least four dilutions of each vaccine shall 
be tested. Each test shall be performed as follows:
    (a) Mice. Healthy mice shall be used, all from a single strain and 
of the same sex, or an equal number of each sex in each group, with 
individual weights between 10 and 14 grams. A group of at least 16 mice 
shall be used for each dilution of each vaccine. In addition, there 
shall be at least 4 groups consisting of no less than 10 mice each for 
each potency test as a control for virulence titration of the challenge 
suspension.
    (b) Injections of vaccine. Serial dilutions, no greater than 
fivefold, of the vaccine to be tested and of the appropriate serotype 
standard vaccine shall be made in 0.85 percent sodium chloride solution. 
The median effective dose (ED50), which is the dose of vaccine that 
is expected to protect 50 percent of the animals that received the 
vaccine, shall be bracketed by the dilutions used. Each mouse in each 
dilution group shall receive intraperitoneally 0.5 milliliter of the 
appropriate vaccine dilution. At least 87.5 percent of the mice in each 
dilution group shall survive, and all surviving mice shall appear 
healthy at the time of challenge.
    (c) The challenge. The challenge shall be administered 12 to 16 days 
after injection of the vaccine.
    (1) The strains of V. cholerae for challenge shall be Ogawa 41 and 
Inaba 35A3, except that V. cholerae, Inaba serotype, strain V86 may be 
used instead of Inaba serotype, strain 35A3, for preparation of vaccine 
challenge culture: Provided, That the source of the challenge culture 
shall be identified and verified by the manufacturer as equal to that 
distributed by the World Health Organization. For each test, the 
challenge culture shall be taken from a batch of cultures maintained by 
a method such as freeze-drying that retains constancy of virulence.
    (2) The challenge and virulence titration doses shall be prepared as 
follows: The bacteria for each challenge shall be harvested from a 6- to 
18-hour culture grown at 36 deg.plus-minus1 deg. C, on a suitable 
agar medium adjusted to pH 7.4. The harvested bacteria shall be 
uniformly suspended in a diluent consisting of M/15 phosphate buffered 
saline adjusted to pH 7.4 and shall contain 0.1 to 0.2 percent gelatin. 
The suspension shall be free from agar particles and clumps of bacteria. 
The suspension shall be adjusted to an opacity of 10 units, and diluted 
in tenfold increments using the same diluent. The suspensions for the 
challenge and virulence titrations shall be suspended in a 5 to 10 
percent sterile gastric mucin preparation adjusted to pH 7.4. The 
challenge suspension shall be prepared from whichever bacterial dilution 
provides the required median lethal dose (LD50) for a 0.5 
milliliter challenge dose. The LD50 is the dose of the challenge 
suspension that is expected to kill 50 percent of the animals that 
received the challenge. The virulence titration suspensions shall 
consist of the challenge suspension and at least three dilutions of the 
challenge suspension calculated to bracket the LD50 value.
    (3) At least 16 surviving mice, randomly selected from each dilution 
group that received vaccine, shall be inoculated intraperitoneally with 
a 0.5-milliliter dose of the challenge suspension. Mice in each of the 
four groups of control mice used for the virulence titration of the 
challenge suspension shall be inoculated intraperitoneally with a 0.5-
milliliter dose of the challenge suspension and its respective 
dilutions. The challenge dose control mice shall be inoculated last. The 
interval between removal of the bacteria from the culture medium and the 
inoculation of the last mouse shall not exceed 2\1/2\ hours.
    (d) Recording the results. The mice shall be observed daily for 2 
days following challenge. A daily record shall be maintained of the 
number of mice that die. A record of the number of mice that survive 
shall be made at the end of the observation period.
    (e) Validity of the test. The test is valid provided: (1) The 
ED50 value of the vaccine under test and the standard vaccine is 
between the largest and smallest doses inoculated into the mice;

[[Page 80]]

    (2) The homogeneity of the dose response lines for both the vaccine 
under test and the standard vaccine is acceptable;
    (3) The log-dose response lines for the vaccine under test and the 
standard vaccine are shown to be parallel by an appropriate statistical 
method;
    (4) The results of all dilutions shall be used to calculate the 
ED50 value of both the standard and test vaccine by a parallel line 
bioassay method or a method statistically equivalent;
    (5) The challenge dose contains between 100 and 10,000 LD50 
doses; and
    (6) The LD50 value of the challenge suspension contains no more 
than 10,000 colony-forming units determined by plate count.
    (f) Repeat tests. Repeat tests need be performed only on the 
serotype which failed to meet the potency requirements prescribed in 
paragraph (h) of this section. The results of each test on each serotype 
meeting the criteria in paragraph (e) of this section shall be combined 
by means of a geometric mean. The determination that the vaccine meets 
the potency requirements shall be made from the results of not more than 
three valid tests on each serotype.
    (g) Estimate of the potency. The ED50 value of each vaccine 
shall be calculated. The protective unit value of each serotype per 
milliliter of the vaccine under test shall be calculated in terms of the 
unit value of the corresponding standard vaccine.
    (h) Potency requirements. The vaccine shall have a potency of not 
less than 8 units per serotype per milliliter. This requirement shall be 
met only if the potency for a single test is not less than 4.4 units per 
serotype per milliliter, or for two tests not less than 5.3 units, or 
for three tests not less than 5.7 units.

[41 FR 18295, May 3, 1976, as amended at 41 FR 46587, Oct. 22, 1976]



Sec. 620.34   Mouse toxicity test.

    The final vaccine shall be demonstrated to be free from toxicity by 
the following test: A group of no less than 10 and no more than 40 mice, 
each mouse weighing 14 to 16 grams, shall have free access to food and 
water at least 2 hours before injection and throughout the test period. 
The group weight of the mice shall be determined immediately before 
injection. Each mouse shall be injected intraperitoneally with a test 
dose of 0.5 milliliter of undiluted vaccine. The group weight of the 
mice shall be determined again at the end of 72 hours. The 72-hour 
average weight per mouse shall be no less than the average weight per 
mouse immediately preceding the injection. No more than 5 percent of the 
total number of mice used may die during the test period; however, 
neither death nor significant toxic signs attributable to the vaccine 
shall result.

[41 FR 18295, May 3, 1976]



Sec. 620.35   General requirements.

    (a) Freezing prohibition. Cholera Vaccine shall not be frozen at any 
time.
    (b) Dose. These standards are based on a total immunizing dose of 
two injections of 0.5 milliliter and 1.0 milliliter, respectively, given 
at intervals specified in the manufacturer's labeling.
    (c) Date of manufacture. The date of manufacture shall be the date 
of initiation of the last valid potency test for the Ogawa serotype or 
the Inaba serotype, whichever date is earlier.
    (d) Labeling. In addition to the applicable labeling provisions of 
this chapter, the package label shall bear the following: (1) A 
statement that the vaccine contains 8 units of each serotype antigen per 
milliliter.
    (2) The statement, ``DO NOT FREEZE''.
    (3) The statement, ``SHAKE WELL''.
    (e) Samples; protocols; official release. For each lot of vaccine, 
the following material shall be submitted to the Director, Center for 
Biologics Evaluation and Research, Food and Drug Administration, 8800 
Rockville Pike, Bethesda, MD 20892.
    (1) A sample consisting of no less than 40 milliliters of the 
product. The sample may be in the final container or from the vaccine 
bulk lot.
    (2) A protocol which consists of a summary of the history of 
manufacture of each lot including all results of each test for which 
test results are requested by the Director, Center for Biologics 
Evaluation and Research,

[[Page 81]]

Food and Drug Administration. The raw data and results from each potency 
test performed shall be included.
    (3) The product shall not be issued by the manufacturer until 
written notification of official release of the lot is received from the 
Director, Center for Biologics Evaluation and Research.

[41 FR 18295, May 3, 1976, as amended at 42 FR 27582, May 31, 1977; 49 
FR 23834, June 8, 1984; 51 FR 15610, Apr. 25, 1986; 55 FR 11013, Mar. 
26, 1990]