In January 2020, FDA released final guidance on use of minimal residual disease tests in clinical trials for hematologic malignancies (MRD; here).
Fast forward to May 2022. FDA releases a draft guidance for use of circulating tumor DNA (ctDNA) in clinical trials for solid cancers. 11 pages, find it here. The LCD covers three use cases, ctDNA for patient selection, ctDNA for patient enrichment, and ctDNA as a measure of response. They note (page 8) that tests might be bespoke (tumor-informed such as post tumor exome sequencing) or tumor-naive. They note that tumor naive panels could like at epigenomic methylation or fragmentomics.
The Federal Register comment period notice will be in the Fed Reg on May 3. Here. The comment period will run 60 days (about July 1).