Temporal trends of registrational randomized clinical trials of new cancer drugs used suboptimal control arms.

(A) Annual numbers of oncology randomized clinical trials that used a suboptimal control arm in mainland China. (B) Annual and cumulative numbers of patients exposed to suboptimal treatment of oncology randomized clinical trials in mainland China. Abbreviation: IRB, institutional review board. Note: For the 5 trials that did not disclose their plan of patient enrolment, we used the actual number of participants as of 31 August 2022 alternatively.