This is really confusing to me. We make seasonal flu vaccines every year. Among them, for other coronaviruses. Why would it take a year and a half to make this one?
ED: Looking into this some more, and it makes even less sense. I ran into this about how vaccines against wild-type bird flus are made:
Making a Candidate Vaccine Virus (CVV) for a HPAI (Bird Flu) Virus | Avian Influenza (Flu)
Apparently they're more difficult than seasonal flu vaccines because bird flus tend to kill the eggs that vaccines are grown in... and despite that, it "is a multistep process that takes months, from start to finish". And one of those steps is the distribution of the finished vaccine.
ED2: Looks like they expect to have the answer to whether Modena's vaccine is both safe and effective by July or August. According to Fauci.
First potential coronavirus vaccine arrives in US