IVX-121

IVX-121 is an investigational virus-like protein vaccine. It is also known by the product name IVX-A12. The vaccine is being developed to protect against two common respiratory viruses: respiratory syncytial virus (RSV) and human metapneumovirus (hMPV).

What is IVX-121?

IVX-121 is a virus-like particle (VLP) subunit vaccine. Virus-like particles mimic the structure of a virus but do not contain the genetic material needed to cause infection. The substance is classified in the therapeutic area of respiratory tract diseases.^[1] It is an investigational substance with no marketing authorisation in the product records.^[1] The product is supplied by AstraZeneca AB.^[1] In the registered trial records, IVX-121 is part of a fixed combination product known as IVX-A12.^[1]

How does IVX-121 work?

IVX-121 is a virus-like particle vaccine. VLPs are designed to resemble the outer structure of a virus, which helps the immune system recognise and respond to it without causing an actual infection. The vaccine is intended to stimulate an immune response against RSV and hMPV, two viruses that can cause lower respiratory tract disease, particularly in older adults.

Which conditions is it used or studied for?

• Respiratory syncytial virus (RSV) — a common respiratory virus that can cause serious lung infections, especially in older adults.
• Human metapneumovirus (hMPV) — a respiratory virus related to RSV that can also lead to lower respiratory tract disease.

How is IVX-121 given?

IVX-121 is given as a solution for injection by the intramuscular route.^[1] In the Phase 3 trial, a single dose of 300 micrograms of the IVX-A12 combination product is being tested.^[1]

What do the clinical trials show?

One registered trial is currently evaluating IVX-121. It is a Phase 3 study in adults aged 60 years and older.^[1] The trial is authorised and plans to enrol 29,450 participants.^[1]

The study compares a single intramuscular injection of IVX-A12 with a placebo, which is a 0.9% sodium chloride solution for injection.^[1] The main outcomes being measured are the occurrence of the first RSV-confirmed lower respiratory tract disease (LRTD) and the first hMPV-confirmed LRTD, starting from day 15 during the first season after vaccination.^[1]

An earlier first-in-human Phase 1/1b randomised trial evaluated the safety and immunogenicity of IVX-121 in healthy young and older adults.^[2] Immunogenicity refers to how well the vaccine triggers an immune response.