Production and evaluation of a chromatographically purified Vero cell rabies vaccine (PVRV) in China using microcarrier technology

Figures & data

Table 1. Comparison of cell density, virus titer, and harvest time among different volumes of microcarriers

Microcarrier density (g/L)	Primary cell density (cells/ml)	Final cell density (cells/ml)	Highest viral titer (LD50/ml)	Average viral titer (LD50/ml)	Harvest time (d)
5	0.3 × 10^6	0.3 × 10^7	7.2	6.7	13
15	0.8 × 10^6	0.8 × 10^7	7.6	7.0	19
20	1.2 × 10^6	1.2 × 10^7	8.0	7.2	18–22
25	1.5 × 10^6	1.5 × 10^7	8.5	7.6	22–24

Table 2. Quality indicators in three batches of purified intermediate SPEEDA PVRV

Sample number	Protein level before purification (µg/g)	Protein level after purification (µg/g)	Impurity protein removal (%)	Glyco- protein recovery (%)	Residual DNA level (pg/0.5 ml)	Residual bovine serum albumin (ng/0.5 ml)	Potency (IU/0.5 ml)
20030301	14600	75	99.95	79.5	< 10	< 25.0	5.70
20030302	15100	72	99.95	80.1	< 10	< 12.5	7.01
20030303	15900	73	99.95	79.7	< 10	< 25.0	6.02

Table 3. Quality of SPEEDA PVRV according to the national standard of rabies vaccine for human use

Items	National standard of rabies vaccine for human use	SPEEDA ® PVRV
Sterility test Residual bovine serum albumin Potency test	Negative (-) ≤ 50 ng/dose ≥ 2.5 IU/dose	Negative (-) ≤ 50 ng/dose ≥ 4.5 IU/dose
Residual Vero cell DNA	≤ 100 pg/dose	≤ 100 pg/dose
Bacterial endotoxin	≤ 50 EU/dose	≤ 50 EU/dose
Total protein	≤ 80 μg/dose	≤ 80 μg/dose
Host protein	≤ 4 μg/dose	≤ 4 μg/dose
Antibiotics	≤ 50 ng/dose	-
pH	7.2–8.0	7.2–8.0

Table 4. Local reactions of the control and test groups after vaccination

Group	Injection	Observed subjects	Pain, itching		Swelling		Induration		Total
			number	%	number	%	number	%	number	%
Test group	1	502	8	1.59	2	0.40	0	0	10	2.0
	2	467	2	0.43	1	0.21	0	0	3	0.64
	3	452	1	0.22	1	0.22	0	0	2	0.44
	4	443	0	0	0	0	0	0	0	0
	5	432	0	0	0	0	0	0	0	0
	Total	2296	11	0.48	4	0.17	0	0	15	0.65
Control group	1	100	1	1.0	0	0	1	1.0	2	2.0
	2	97	0	0	0	0	0	0	0	0
	3	93	0	0	0	0	0	0	0	0
	4	85	0	0	0	0	0	0	0	0
	5	85	0	0	0	0	0	0	0	0
	Total	460	1	0.23	0	0	1	0.22	2	0.43

Table 5. Abnormal reaction rate of temperature in the control and test groups after vaccination

Group	Injection	Observed subjects	Weak reaction		Moderate reaction		Strong reaction		Total
			number	%	number	%	number	%	number	%
Test group	1	502	1	0.19	4	0.8	0	0	5	1.0
Control group	1	100	0	0	1	1.0	0	0	1	1.0

Table 6. Comparison of antibody conversion and geometric mean titer (GMT) between the test and control groups after vaccination

Group	0 d			14 d			45 d
	Neutralizing antibody (IU/ml)	GMT (IU/ml)	Positive rate (%)	Neutralizing antibody (IU/ml)	GMT (IU/ml)	Positive rate (%)	Neutralizing antibody (IU/ml)	GMT (IU/ml)	Positive rate (%)
Test group	≤ 0.2	≤ 0.2	0	0.8–11.9	5.2	100	2.7–29.2	9.5	100
Control group	≤ 0.2	≤ 0.2	0	0.9–12.7	5.6	100	1.5–25.4	9.8	100