that's pretty much how it works. even when it comes live, the price will already be somewhere major; shorta like how some people (MMs and such) trade 24/7 but we (the retail investor) ony get specific hours. :)
If the drug is approved, there will be a halt (T1) to dissemenate information through Reg. FD compliant channels. Once the news is out it would resume trading.
If the drug is not approved - the press release usually comes after the market closes.
They have to halt during the day for an approval because FDA updates their website about the approval around the same time that they send word to the sponsor. the sponsor then has to rush out. a press release and does T1 - T2 - T3 halting. It won't be halted all day like with the ADCOMM
Exactly, Adcom is a one day event leading up to a vote. The FDA approval happens behind closed doors and the company is notified if it is or is not cleared for Marketing and if there are any restrictions or not. Then the Company makes a press release either before or after Market hours. With my experience it seems to mostly come in the morning before Market open.