These are becoming more common. Agrawal et al. (2022) using data between 2002-2021, found that FDA approvals:
…176 new hematology malignancies and oncology indications based on single-arm trials, including 116 accelerated approvals (AA) and 60 traditional approvals. Overall, 87 approvals (49%) were for new molecular entities or original biologics, and 89 (51%) were for supplemental indications.Response rate (RR) was the most common endpoint used to support approval of these single-arm trials (173 of 176 [98%]). Of the 116 AAs based on single-arm trials, as of December, 45 (38%) met the requirements for postmarketing clinical benefit verification, 61 (52%) were awaiting benefit verification, and 10 (9% ) will be withdrawn from the market on 31st 2021.
