December 11, 2023

Respiratory syncytial virus – virus vaccine under investigation

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PfizerThe company’s vaccine, which protects adults 60 and older from respiratory syncytial virus infection, was slightly less effective after 18 months, according to clinical trial results released Wednesday.

Data from New York-based Pfizer Clinical Trials More than 34,000 older adults were studied over two RSV seasons or 24 months.Latest data specifically for Northern Hemisphere ‘mid-season 2’ participants try outwhich is about 18 months after vaccination.

For more severe lower respiratory disease with three or more symptoms after 18 months, the vaccine was 78.6 percent effective, slightly less than 85.7% in a year. These symptoms include wheezing, shortness of breath, rapid and shallow breathing, and mucus production.

According to Pfizer, the vaccine was about 49 percent effective after 18 months in people with two or more symptoms of the same disease. Compared with the 66.7% efficacy rate at one year, the decline was even greater.

The vaccine was generally well tolerated, with no adverse events reported by participants at 18 months.

Pfizer to advisory committee Centers for Disease Control and Prevention on Wednesday. The committee will form recommendations on when and how often the company’s RSV vaccine should be administered in the United States, given that the US Food and Drug Administration has approved the shot.

Pfizer’s RSV vaccine is second to get approval GlaxoSmithKlinewith similar longer-term data on Wednesday.

Pfizer’s results are the first to demonstrate the durability of its vaccine in preventing RSV, which causes mild cold-like symptoms in most people but causes more serious infections in older adults and children.

The data suggest that the protection provided by the vaccine wanes over time, similar to what has been observed with Covid and flu shots.

But the 18-month data also showed that Pfizer’s vaccine was still generally protective against RSV a year later.

It’s not clear how effective the vaccine will be after 24 months. Pfizer is expected to release the data later this year, which will better illustrate how long-lasting the injectable is.

Annaliesa Anderson, head of Pfizer’s vaccine development, told CNBC that the company is “very encouraging” by the data from the Phase III trial.

She noted that the vaccine remained highly effective against lower respiratory disease with three or more symptoms, which was more severe than the same disease with two or more symptoms.

“As with most vaccines, what you’re really looking for is the effect on more severe disease that leads to higher mortality, morbidity and healthcare-related exposure,” Anderson told CNBC. “It’s very important for us to be able to see high efficacy Important, we think it will make people feel comfortable when they get vaccinated.”

Pfizer has yet to release data on the effectiveness of its vaccine against severe RSV disease, which is defined as patients requiring hospitalization, oxygen support or mechanical ventilators.

Research is ongoing, Anderson said, as are studies evaluating the vaccine’s efficacy in older adults with weakened immune systems.

According to the CDC, RSV kills 6,000 to 10,000 older adults each year and hospitalizes 60,000 to 160,000 of them.

The risk of hospitalization increases with age, with adults 70 and older being more vulnerable.

Pfizer estimates that if 50% of people age 60 and older received the seniors vaccine, the vaccine could prevent more than 5,000 deaths, 68,000 hospitalizations, 51,000 emergency department visits and more than 422,000 outpatient visits.