Elaine Mardis, PhD, Co-director of The Genome Institute at Washington University School of Medicine, St. Louis, commented on the IMPaCT trial and the constraints of the U.S. health-care system.
“The correct clinical trial has not yet been performed to demonstrate the clinical utility of genomic sequencing to determine treatment with targeted therapies. In other words, do patients have better outcomes (so defined) when their genome is studied to determine a targeted therapy they might respond to vs the standard of care,” Dr. Mardis wrote in an e-mail.
Her second point refers to reimbursement. “While historically insurance payors have covered the cost of most single-gene sequencing assays or other ‘companion diagnostics,’ the current Centers for Medicare and Medicaid Services (CMS) determination is that code-stacking the cost of multiple single-gene assays is not reimbursable. As such, panels of genes or exomes are not being reimbursed by insurance companies [so someone else has to pay]. Hence, the number of patients who can afford these assays from their own pockets is limited,” she wrote.
In the IMPaCT study, the research was supported by government and foundation funding. Dr. Mardis commented that several large cancer centers, including Memorial Sloan Kettering Cancer Center and MD Anderson Cancer Center, have raised funds to study clinical utility and reimbursement of genomic sequencing by generating genomic data for patients and using those data to enroll patients onto clinical trials.
“Earliest reports from these efforts are that while many patients can be identified with a mutation in a known driver gene, sometimes the impact of the mutation on the protein function is unknown [variants of unknown significance], the variant is known but the drug is not approved in that disease site [off-label indication], or there is not a clinical trial available for that gene/drug combination and/or disease site,” Dr. Mardis continued.
The drug clinical trials design and U.S. Food and Drug Administration (FDA) approval conundrum is another factor that limits this approach. “While FDA has its new breakthrough status to get drugs to patients more quickly, pharmaceutical companies have been slow to open trials that accept most or all cancer patients regardless of disease site for a given gene/drug combination [‘basket’ or ‘bucket’ trials]. So, drugs that might otherwise reach breakthrough status quickly in multiple tissue sites are slow to become available via the basket/bucket trial design,” she stated. ■
Disclosure: Dr. Mardis reported no potential conflicts of interest.