Merck is set to commence two new Phase III studies of PCV-15 (V114), an investigational polyvalent conjugate vaccine to prevent pneumococcal disease.

The first trial NCT03480763 aims to evaluate the safety, tolerability, and immunogenicity of PCV-15 (V114) and Prevnar 13 in healthy adults aged 50 or older.

It also seeks to examine the safety of sequential administration of PCV-15 (V114) or Prevnar 13 followed by PNEUMOVAX 23 one year later.

“Based on our Phase I and II studies of PCV-15 findings, we are initiating a comprehensive Phase III programme to further evaluate this investigational vaccine.”

The trial further expects to evaluate the immune responses to the 15 serotypes contained in PCV-15 (V114) when PNEUMOVAX 23 is given around 12 months after receipt of either PCV-15 (V114) or Prevnar 13.

A total of 600 subjects are expected to be enrolled in this randomised, double-blind, active comparator-controlled study.

The second trial NCT03480802 is designed to analyse the safety, tolerability, and immunogenicity of PCV-15 (V114) and Prevnar 13 in pneumococcal vaccine-naïve adults infected with human immunodeficiency virus (HIV).

It also intends to determine the safety, tolerability, and immunogenicity of PNEUMOVAX 23 when given eight weeks after receipt of either PCV-15 (V114) or Prevnar 13.

The trial aims to enrol around 300 subjects.

Merck Research Laboratories senior vice-president Eliav Barr said: “Based on our Phase I and II studies of PCV-15 findings, we are initiating a comprehensive Phase III programme to further evaluate this investigational vaccine.”

Merck, which is currently known as MSD outside the US and Canada, is engaged in the development of medicines and vaccines for various challenging diseases.