Curevo Vaccine has concluded subject enrolment in a Phase IIb clinical trial of a CRV-101 subunit vaccine for prevention of the varicella zoster virus (shingles) reactivation in older adults. 

The trial enrolled a total of 678 subjects aged over 50 years, without any previous varicella zoster virus vaccination or shingles infection, at 11 sites in the US.

These subjects were randomised to receive a high or low dosage of CRV-101 or GlaxoSmithKline’s (GSK) shingles vaccine, Shingrix. 

In accordance with the existing practice for a shingles vaccine, the subjects were given two vaccine doses at a gap of two months.

Safety and immunologic outcomes, including the incidence of local and systemic side effects, as well as antibody levels at the third month, are some of the trial’s primary endpoints. 

Comparing CRV-101’s reactogenicity to Shingrix and the incidence of serious adverse events are also included as the primary endpoints. 

The company anticipates reporting topline findings from the trial in January next year.

An adjuvanted subunit vaccine, CRV-101 is being analysed to prevent shingles in older people. 

Curevo Vaccine Clinical Operations and Development director Lisa Shelton said: “Rapid enrolment of a large trial quickly in a challenging research environment during the pandemic is a credit to our nimble clinical operations and project management team. 

“The innovative measures we took to reduce key risks to enrolment worked were successful, and we look forward to applying these measures to Curevo’s future clinical programmes.”

The Phase IIb trial was based on a successful Phase I clinical trial in healthy subjects aged 18 to 50 years. 

Phase I trial data showed that the CRV-101 vaccine was well tolerated, with strong cellular and humoral immunogenicity. 

Based on Phase IIb data, Curevo will design an international Phase III programme, planned to commence next year.