NEW RSV VACCINE GIVEN DIRECTLY TO NEWBORNS AND INFANTS
The FDA has just granted fast-track approval for a new version of this already-existing vaccine. The Product Insert is now available here.
This new product, however, isn’t actually a vaccine. Vaccines technically are the germ components that stimulate an immune response (antibodies) in the body to provide protection from infection. Nirsevimab contains the actual antibodies genetically engineered then injected to provide some artificial immunity in a baby. An older version of this preventive treatment, called Synagis, has been around for decades and has been recommended mainly for premature babies (in whom RSV can be much more severe). This new version is recommended for ALL newborns to help reduce the severity of RSV during their first winter. It can also be given to infants with severe heart and lung disease for their second winter as well.
The injection is given as a single one-time dose before the start of RSV season (around October).
How it is made/ingredients: This is a genetically-engineered monoclonal antibody produced in a laboratory using hamster ovary cells to generate batches of these proteins. The antibodies are then mixed with two amino acids, some sucrose, polysorbate 80 and water.
Side effects: The main side effect of concern is allergic reaction. The exact risk of this rare reaction is not yet known.
A new report in the Japanese Medical Journal Med Check analyzed data from two of the vaccine trials and found a higher rate of non-RSV complications, such as stroke, blood clotting, hypotonic hyporesponsive episodes, in those given the vaccine compared to those who didn’t. The rate of overall serious side effects was about 1 in 1600 doses.
I have not yet given any patients this injection, but will begin discussing it with them. I don’t plan to offer it to patients yet, but if I ever do, and I experience any problems with it, I will update this information here.
Cost: It will cost about $620 for this one-time injection.