A Phase 3 Clinical Trial to Evaluate Long-term Immunogenicity and Boostability of Purified Chick-Embryo Cell Rabies Vaccine in Adults Following Primary Series of Pre/Exposure Prophylaxis.

Number of Participants Reporting Serious Adverse Events (SAEs) After a Booster Dose of Purified Chick Embryo Cell Culture (PCEC) Rabies Vaccine

A SAE is defined as any untoward medical occurrence that at any dose results in one or more of the following: death, is life-threatening, required/prolonged hospitalization, persistent or significant disability/incapacity, congenital anomaly/or birth defect, an important and significant medical event that may not be immediately life threatening or resulting in death or hospitalization but, based upon appropriate medical judgment, may jeopardize the participants or may require intervention to prevent one of the other outcomes listed. Safety is assessed as the number of participants reporting SAEs after a booster dose of PCEC rabies vaccine administered in this extension study, if RNVA concentrations were \<0.5 IU/mL, following a primary series of accelerated or conventional rabies pre-exposure (PrEP) intramuscular (IM) regimen in the parent study.

Time frame: From booster vaccination [6 to 9 months after Year 3 (3 years after primary series of vaccination)] up until completion of the safety follow-up period (10 years after primary series of vaccination)

Number of Participants Who Had Their Rabies Virus Neutralizing Antibody (RNVA) Concentrations Drop Below 0.5 International Units (IU) Per Milliliter (mL) Between Day 366 and Year 3

Time frame: Day 366 to Year 3 (after primary series of vaccination)

Number of Participants Who Had Their RNVA Concentrations Drop Below 0.5 IU/mL Between Year 3 and Year 4

Time frame: Year 3 to Year 4 (after primary series of vaccination)

Number of Participants Who Had Their RNVA Concentrations Drop Below 0.5 IU/mL Between Year 4 and Year 5

Time frame: Year 4 to Year 5 (after primary series of vaccination)

Number of Participants Who Had Their RNVA Concentrations Drop Below 0.5 IU/mL Between Year 5 and Year 6

Time frame: Year 5 to Year 6 (after primary series of vaccination)

Number of Participants Who Had Their RNVA Concentrations Drop Below 0.5 IU/mL Between Year 6 and Year 7

Time frame: Year 6 to Year 7 (after primary series of vaccination)

Number of Participants Who Had Their RNVA Concentrations Drop Below 0.5 IU/mL Between Year 7 and Year 8

Time frame: Year 7 to Year 8 (after primary series of vaccination)

Number of Participants Who Had Their RNVA Concentrations Drop Below 0.5 IU/mL Between Year 8 and Year 9

Time frame: Year 8 to Year 9 (after primary series of vaccination)

Number of Participants Who Had Their RNVA Concentrations Drop Below 0.5 IU/mL Between Year 9 and Year 10

Time frame: Year 9 to Year 10 (after primary series of vaccination)

RVNA Antibody Concentrations 7 Days After the Booster Dose

RVNA antibody concentrations were measured in terms of Geometric Mean Concentrations (GMCs) and expressed in IU/mL. The booster dose was administered in this Extension study (conducted from Year 3 to Year 9 after the primary schedule study) only when participants had RVNA concentrations \<0.5 IU/mL at the yearly immunogenicity check (i.e., at "Scheduled Clinic Visit"). Booster dose administration occurred at an approximate timepoint between 6 and 9 months from the previous "Scheduled Clinic Visit" during the Years 3 to 9.

Time frame: At Day 7 after booster dose

RVNA Geometric Mean Ratios (GMRs) 7 Days After the Booster Dose Versus Antibody Concentrations Before the Booster Dose

GMR was calculated as ratio of post booster dose RVNA GMCs (7-day post booster dose) to the baseline RVNA GMCs (7 days before booster dose). The booster dose was administered in this Extension study (conducted from Year 3 to Year 9 after the primary schedule study) only when participants had RVNA concentrations \<0.5 IU/mL at the yearly immunogenicity check (i.e., at "Scheduled Clinic Visit"). Booster dose administration occurred at an approximate timepoint between 6 and 9 months from the previous "Scheduled Clinic Visit" during the Years 3 to 9.

Time frame: Day 7 after booster dose compared to baseline (7 days before booster dose)

Percentage of Participants With RVNA Concentrations Greater Than or Equal to (>=) 0.5 IU/mL, 7 Days After Booster Dose

The booster dose was administered in this Extension study (conducted from Year 3 to Year 9 after the primary schedule study) only when participants had RVNA concentrations \<0.5 IU/mL at the yearly immunogenicity check (i.e., at "Scheduled Clinic Visit"). Booster dose administration occurred at an approximate timepoint between 6 and 9 months from the previous "Scheduled Clinic Visit" during the Years 3 to 9.

Time frame: At Day 7 after booster dose

Percentage of Participants With RVNA Concentrations >= 0.5 IU/mL at Year 3

Time frame: At Year 3 after primary series of vaccine administration

Percentage of Participants With RVNA Concentrations >= 0.5 IU/mL at Year 4

Time frame: At Year 4 after primary series of vaccine administration

Percentage of Participants With RVNA Concentrations >= 0.5 IU/mL at Year 5

Time frame: At Year 5 after primary series of vaccine administration

Percentage of Participants With RVNA Concentrations >= 0.5 IU/mL at Year 6

Time frame: At Year 6 after primary series of vaccine administration

Percentage of Participants With RVNA Concentrations >= 0.5 IU/mL at Year 7

Time frame: At Year 7 after primary series of vaccine administration

Percentage of Participants With RVNA Concentrations >= 0.5 IU/mL at Year 8

Time frame: At Year 8 after primary series of vaccine administration

Percentage of Participants With RVNA Concentrations >= 0.5 IU/mL at Year 9

Time frame: At Year 9 after primary series of vaccine administration

Percentage of Participants With RVNA Concentrations >= 0.5 IU/mL at Year 10

Time frame: At Year 10 after primary series of vaccine administration