Those are turning into more and more commonplace. Agrawal et al. (2022) use knowledge between 2002-2021, and located that FDA authorized:

…176 new malignant hematology and oncology indications in accordance with single-arm trials, together with 116 speeded up approvals (AAs) and 60 conventional approvals. General, 87 approvals (49%) have been for brand spanking new molecular entities or authentic biologics and 89 (51%) have been supplemental indication. Reaction fee (RR) was once the most typical finish level used to enhance approval in those single-arm trials (173 of 176 [98%]). Of the 116 AAs in accordance with single-arm trials, 45 (38%) fulfilled their postmarketing requirement to make sure scientific get advantages, 61 (52%) are pending verification of get advantages, and 10 (9%) have been withdrawn from the marketplace as of December 31, 2021.