You asked, we answered: Is it safe for SM-102 to be in the Moderna COVID-19 vaccine?

COVID-19 vaccine vials


Does the Moderna COVID-19 vaccine contain SM-102? Is it true that SM-102 is not approved for use in humans?

Answer from infectious diseases expert James Lawler, MD:

Yes, the Moderna COVID-19 vaccine does contain SM-102. And yes, the vaccine is safe. 

SM-102 is a lipid molecule. (A lipid molecule is a molecule that does not dissolve in water.) The molecule helps form the lipid nanoparticles in the Moderna vaccine. (A lipid nanoparticle is an extremely small amount of matter that doesn’t dissolve in water.)

When used for things other than medicines, SM-102 is sometimes mixed with chemicals that aren’t meant for human consumption. That’s why some safety data sheets may list warnings for SM-102.

The U.S. Food and Drug Administration (FDA) carefully considers every ingredient in all vaccines to ensure they are safe. They even explore ingredients that are just used in the manufacturing process. We know the FDA knows about this specific ingredient in the Moderna vaccine. They listed it in their Emergency Use Authorization letter. Plus, vaccine makers are required to employ Current Good Manufacturing Practices when making or buying ingredients. You can read those standards here.

Patients should always feel empowered to look up the ingredients in any vaccine. Reading the information on is a good place to start. We’ve also listed COVID-19 vaccine ingredients in this blog.

If you come across a vaccine ingredient that causes confusion or worry, please have an open conversation with your doctor about it. Nebraska Medicine patients can send a message to their doctor through the Nebraska Medicine app or the One Chart | Patient portal.