“A common question I received after my tweet on the PEGASUS trial is that what ctDNA clearance in the blood could mean for patients.

This is a very valid question and we don’t know the exact answer yet but we have some clues. Here is a brief discussion on this.

Although we do not know the impact of ctDNA clearance on clinical outcomes particularly with FOLFIRI, the GALAXY trial did suggested the patients who clears the CtDNA after adjuvant chemotherapy did as good as those who had negative CtDNA.

Important to note that ctDNA clearance and repositivity is a dynamic process and clearance can be temporary.
So, duration of negative ctDNA would be more important than single -time negative results.

Most importantly the impact of clearance of ctDNA will be more definite once the long-term outcomes of this study and CIRCULATE US trials are released.

ctDNA remains as a puzzle for us however future holds promise for this molecular biomarker to guide us for treatment decisions process for a more precision care of our patients.”

Source: Ibrahim Halil Sahin/X