The Accelerated Approval program allows for commercialisation...

The Accelerated Approval program allows for commercialisation after a P2, though the drug company is still supposed to undertake a subsequent confirmatory P3. Apparently some have been a bit slack about that requirement though.

"For the past 20 years, the accelerated approval category has allowed early access to cancer drugs that showed promise in addressing unmet needs for treatment of potentially fatal disease, and more than 35 new cancer drugs have received marketing permission by this new route.3 Of the agents approved by this mechanism, full approval has subsequently been granted to most (the exact number is not available on the FDA website), although a small number of agents have been withdraw for safety (gemtuzumab) or efficacy (gefitinib in lung cancer and bevicizumab in breast cancer) reasons. This mechanism has not been without controversy, as both the FDA and its critics have noted a failure to complete the required confirmatory trials postapproval in perhaps a third to one-half of accelerated approvals.3"

https://ascopubs.org/doi/full/10.14694/EdBook_AM.2012.32.114

@Pledge if you want the examples, the FDA website has the entire list of them:

https://www.fda.gov/drugs/nda-and-bla-approvals/accelerated-approval-program