What is minimal residual disease (MRD) testing?
MRD testing finds very small amounts of cancer that remain after treatment, below what standard blood tests, biopsies or imaging can detect. It shows how well a treatment is working, how likely a relapse is and what next steps to consider.
Why is genetic and molecular testing a challenge for health plans?
Use is growing fast: Medicare Part B spending on genetic tests passed $2 billion for the first time in 2024. Evidence that a test improves outcomes often lags behind new test development, and 41% of physicians cite insufficient training in choosing and interpreting genetic tests. Plans face three linked challenges: clinical utility, evidence and appropriate use.
Why was RAS called “undruggable”?
RAS mutations drive about 30% of human cancers, but for decades RAS proteins resisted drug design: they lacked obvious binding pockets and bind GTP very tightly. The first KRAS inhibitor, sotorasib, was approved in 2021, but it targets only the KRAS G12C mutation, which is found in just 2% to 3% of pancreatic cancers.
Read: The End of “Undruggable?”: Why RASolute-302 May Mark the Beginning of the Pan-RAS Era
What could pan-RAS inhibitors mean for health plan budgets?
Daraxonrasib could treat roughly five times as many patients as first-generation KRAS therapies, so even with familiar per-patient pricing, the overall budget impact would be much larger. Value goes beyond drug price: oral dosing and lower discontinuation rates can reduce other costs. Biomarker confirmation, indication-specific coverage and real-world monitoring are likely to shape coverage decisions.
Read: The End of “Undruggable?”: Why RASolute-302 May Mark the Beginning of the Pan-RAS Era
What is daraxonrasib?
Daraxonrasib is a first-in-class oral pan-RAS inhibitor. Unlike earlier KRAS drugs that target one mutation, it blocks the active form of mutant and normal KRAS, NRAS and HRAS. In the phase 3 RASolute-302 trial in previously treated metastatic pancreatic cancer, it doubled median overall survival compared with chemotherapy (13.2 vs 6.6 months). It is currently investigational.
Read: The End of “Undruggable?”: Why RASolute-302 May Mark the Beginning of the Pan-RAS Era
Where is MRD testing most established?
In blood cancers. In acute lymphoblastic leukemia, NCCN guidelines call MRD an essential part of patient evaluation, and in multiple myeloma the FDA’s Oncologic Drugs Advisory Committee voted in April 2024 to recognize MRD-negative complete response as an early endpoint for accelerated approval.
Is MRD testing used for solid tumors?
It is emerging. In solid tumors, MRD testing relies on circulating tumor DNA (ctDNA). It is a strong predictor of recurrence, and in May 2026 the FDA approved atezolizumab as adjuvant treatment for muscle-invasive bladder cancer in patients who are ctDNA MRD positive. Routine use is still limited: sensitivity after surgery ranges from about 45% to 70%, and there is no consensus yet on assays, timing or thresholds.