Article by Staff Writer VACCINE supplies are currently making headlines for all the wrong reasons as delays in deliveries from drug manufacturers have sparked rising tensions in Europe and increased concerns about “vaccine nationalism”. While some of the delays are due to manufacturing, others relate to the fill and finish process. In an effort to explain the challenges faced, volunteers from the International Society for Pharmaceutical Engineering UK Affiliate (ISPE UK) and IChemE’s Pharmaceutical Special Interest Group have published the following guide aimed at explaining to the public the process of fill and finish, and drug product release: The usual form for modern vaccines is a liquid (normally sterile water) containing a number of identical fragments of the organism, protein or RNA strand which the body’s immune system will use to train itself to identify the real organism and build antibodies to fight the infection. This liquid and a few chemical additives to help keep things stable is all together called the vaccine. The process to make a vaccine is like making a cake and we follow a very specific recipe detailing each ingredient and each step of the manufacture. It is much more complicated than baking a cake but the analogy is useful. The vaccine is normally made in large quantities (thousands or millions of doses in a batch). This is generically known as the vaccine Drug Substance and it is stored ready for dividing into individual containers such as vials. So again, the analogy would be the cake mixture (being the Drug Substance batch) and each cupcake being the individual doses of vaccine which is generically known as Drug Product.