Pfizer Seeks Expanded Use Of Abrysvo As Vaccine Shows Potential In 18+ Patients

Tuesday, Pfizer Inc PFE released top-line immunogenicity and safety data from the ongoing pivotal Phase 3 MONeT trial, evaluating a single dose of Abrysvo versus placebo in adults 18 to 59 years of age at risk of developing severe respiratory syncytial virus (RSV)-associated lower respiratory tract disease (LRTD).

Among US adults 18 to 49 years, 9.5% have a chronic condition that puts them at risk of severe RSV disease, and this percentage rises to 24.3% among persons 50 to 64 years of age.

However, no RSV vaccines have been approved for use in adults 18 to 59. 

The MONeT study achieved its co-primary immunogenicity endpoints and primary safety endpoint:

Participants demonstrated RSV-A and RSV-B subgroup neutralizing responses non-inferior to the response seen in the Phase 3 RENOIR study of Abrysvo in over 34,000 adults aged 60 or older where vaccine efficacy was previously demonstrated.

Participants also achieved at least a four-fold increase in serum neutralizing titers for RSV-A and RSV-B one month after receiving Abrysvo compared to pre-vaccination.

During the trial, Abrysvo was well-tolerated, and safety findings were consistent with those from previous trials.

Related: GSK’s Competitive Edge, Surpasses Pfizer in Respiratory Syncytial Virus Vaccine Sales.

Pfizer intends to submit these data to regulatory agencies and request expansion of the age group from the current indication to 18 years of age and older.

In February, Pfizer announced top-line Abrysvo vaccine efficacy and safety data in adults 60 years and older following a second season in the Northern and Southern Hemispheres from the ongoing pivotal Phase 3 trial RENOIR. 

Vaccine efficacy against RSV-associated LRTD, defined by three or more symptoms, after disease surveillance in season two was 77.8%.

“We are excited to address a significant unmet need, pending regulatory authority approval, as ABRYSVO has the potential to become the first and only RSV vaccine for adults 18 years and older,” said Annaliesa Anderson, SVP and Head of Vaccine R&D.

Read Next: Pfizer, Sanofi’s Respiratory Syncytial Virus Products Faces Insurance And Logistical Hurdles To Protect Infants.

Price Action: PFE shares are up 0.6% at $26.74 on the last check Tuesday.

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