"Given that full data on the trial will be disseminated via upcoming/future conferences, how does that information then get out to the public at large?  Not everyone follows these events.  Are PRs then typically issued by the company in parallel the following day?"

Most big conferences where data like this are presented have embargo policies in effect for the press/media, investigators and companies. There is often embargoed information (results, etc) shared with the press/media, as well as embargoed interviews, so that news stories from the press/media are ready to publish immediately once the data is presented and the embargo is lifted. It is also quite common, if not required/expected, for the full data publication to be released by the major medical journal at the time of presentation. Also quite common for companies to release their news releases on the data at time of presentation too and common for company webcasts to be done same day. The floodgates open not just same day but pretty much within minutes of the live full data presentation and embargo lift.

BearDownAZ