"The accelerated approval program allows for earlier approval of drugs that treat serious conditions, and fill an unmet medical need based on surrogate or intermediate endpoints. In this case, accelerated approval of Etcamah was granted based on how long patients lived without their disease worsening, measured from the point when the resistance mutation was first detected in the blood"...
“This marks the first FDA approval of a cancer therapy guided by the detection of a resistance mutation in circulating tumor DNA (ctDNA) before imaging tests show that the disease is progressing. But additional evidence is needed to confirm clinical benefit.”"...
https://www.fda.gov/news-events/press-announc...ovdelivery
havent researched yet