Comparison of Safety and Immunogenicity of Purified Chick Embryo Cell Rabies Vaccine (PCECV) and Purified Vero Cell Rabies Vaccine (PVRV) Using the Thai Red Cross Intradermal Regimen at a Dose of 0.1 ML

Abstract

Intradermal (ID) vaccination with modern cell culture rabies vaccines is a means to significantly reduce the cost of post-exposure prophylaxis as compared to intramuscular vaccination. In this study we evaluated the efficacy, immunogenicity and tolerability of PCECV and PVRV administered ID in doses of 0.1 mL per site according to the 2-site Thai Red Cross (TRC) regimen. Patients with WHO category III exposure to suspect or laboratory proven rabid animals were administered either PCECV (n = 58) or PVRV (n = 52) ID at a dose of 0.1 mL per site at two sites on days 0, 3 and 7 and at one site on days 30 and 90. Serum samples were withdrawn on days 0, 14, 30, 90 and 180 and rabies virus neutralizing antibody (RVNA) titers were determined by rapid fluorescent focus inhibition test (RFFIT). Patients who were exposed to laboratory confirmed rabid animals were followed up for one year after exposure. All 110 patients developed RVNA titers above 0.5 IU/mL by day 14. Adequate titers >0.5 IU/mL were maintained up to day 180. Both vaccines induced equivalent RVNA titers at all time points and were well tolerated. Five subjects who were bitten by laboratory confirmed rabid dogs were alive and healthy one year after exposure. As demonstrated, PCECV and PVRV are both immunogenic, efficacious and well tolerated when administered in the TRC post-exposure prophylaxis regimen in ID doses of 0.1 mL as recommended by WHO guidelines. The use of PCECV in this regimen may prove more economical in developing countries like India.

Clinical evaluation of purified chick embryo cell rabies vaccine administered intradermally in animal exposures

“…10 Similarly, a study conducted by Madhusudana et al using TRC regimen showed GMC of 4.3 IU/ml, 9.0 IU/ml, 6.7 IU/ml and 3.7 IU/ml on days 14, 30, 90 and 180 respectively. 11 The immunogenicity of the PCECV in the present study were similar to other studies and it confirms the immunogenicity of PCECV administered intradermally among animal bite victims.…”

Evaluation of a one week intradermal regimen for rabies post-exposure prophylaxis: Results of a randomized, open label, active-controlled trial in healthy adult volunteers in India

“…The RVNA response of present ID regimen was comparable to RVNA response with updated TRC regimen, TRC regimen, 4 site intra dermal regimen and Essen IM regimens using PCECV and PVRV. [13][14][15][16][17] The only other study conducted on 4 site one week regimen is from Thailand by Shantavasinkul et al 3 When we compare our results with this study it is found that while 100% in Thailand about 5% patients do not come for the 4 th dose on day 28. 3 In two recent studies from India where updated TRC, IDRV is given in government hospitals, the completion/compliance rate to full course or taking 4 doses of vaccine including the one on day 28 was found to be 38.5% in a rural clinic and 75.5% in an urban clinic.…”

“…[13][14][15][16][17] However, all subjects in both the vaccine groups tolerated the vaccines and completed the full course of vaccination, thus indicating the acceptability of this new regimen. Indeed, a multiple site ID regimen consisting of 8 inoculations at different sites on day 0 was also well tolerated while it was practiced in the past.…”

Comparison of safety and immunogenicity of 2 WHO prequalified rabies vaccines administered by one week, 4 site intra dermal regimen (4-4-4-0-0) in animal bite cases

“…The dose on day 90 was replaced by giving 2 doses of vaccine on day 28 instead of one. [8][9][10][11][12][13][14][15][16][17] WHO Expert Consultation on Rabies (1 st Report, 2005 and 2 nd Report 2013) has approved the use of updated TRC regimen (2-2-2-0-2) spread over a period of one month and is currently in use in many Asian countries. However, dropout rate is as high as 60% for last dose of vaccination with updated TRC regimen.…”