A Study to Evaluate the Safety and Efficacy of Inactivated Varicella-zoster Vaccine (VZV) as a Preventative Treatment for Herpes Zoster (HZ) and HZ-related Complications in Participants Undergoing Hematopoietic Cell Transplants (HCTs) (V212-001)

Clinical criteria for suspected Herpes-Zoster (HZ) cases were the development of a papular or vesicular rash with a dermatomal or generalized distribution, or in the absence of a rash, clinical suspicion of VZV infection with or without the detection of VZV in diagnostic specimens from blood, cerebrospinal fluid, lung, liver, or other organ. All suspected cases of HZ were subjected to adjudication by the Clinical Adjudication Committee (CAC). Case confirmation was based on skin lesion polymerase chain reaction, if available, or by adjudication of the clinical case description by the CAC, conducted according to the CAC Standard Operations Procedure.

An adverse event (AE) is defined as any unfavorable and unintended change in the structure, function, or chemistry of the body temporally associated with the use of the sponsor's product, whether or not considered related to the use of the product. A serious adverse event (SAE) is an AE that results in death, is life threatening, results in a persistent or significant disability or incapacity, results in or prolongs an existing hospitalization, is a congenital anomaly or birth defect, is a cancer, is an overdose, or is another important medical event.

Moderate to severe HZ-associated pain was defined as 2 or more occurrences of a score 3 or greater (0-to-10 scale, where 0 is no pain and 10 is pain as bad as you can imagine) on the Zoster Brief Pain Inventory (ZBPI) at any time from HZ onset through the end of the 6 month HZ-follow-up period.

The composite efficacy endpoint of the incidence of HZ complications was defined as the occurrence of any of the following during the study: hospitalization or prolongation of hospitalization due to HZ, disseminated HZ (including disseminated HZ rash or VZV viremia), visceral HZ, ophthalmic HZ, neurological impairment due to HZ, or administration of intravenous acyclovir therapy for treatment of HZ.

Postherpetic Neuralgia (PHN) was defined as pain in the area of the HZ rash with pain in the last 24 hours scored as 3 or greater (on a 0 to 10 scale, where 0 is no pain and 10 is pain as bad as you can imagine) on the ZBPI that persists or appears greater than or equal to 90 days after HZ rash onset.

An AE is defined as any unfavorable and unintended change in the structure, function, or chemistry of the body temporally associated with the use of the sponsor's product, whether or not considered related to the use of the product. A serious adverse event (SAE) is an AE that results in death, is life threatening, results in a persistent or significant disability or incapacity, results in or prolongs an existing hospitalization, is a congenital anomaly or birth defect, is a cancer, is an overdose, or is another important medical event.