NEW YORK – The past few years have seen a significant shift in payor attitudes toward liquid biopsy cancer testing, including recent growth in the number of positive coverage policies and a shift toward pan-cancer versus cancer-specific implementation, a new study published this Monday has found.
Reporting their findings in the Journal of the National Comprehensive Cancer Network, investigators from the University of California, San Francisco and City of Hope analyzed about four years of data on both public and private payor coverage of circulating tumor DNA tests in what they believe is the first study of its kind.
The group used a resource called the Canary Insights Database, a public library of more than 40,000 medical policies from commercial and public payers, to track private policies, Medicare National Coverage Determinations (NCDs) and Medicare Administrative Contractor Local Coverage Determinations (LCDs) from 2015 through July 1, 2019.
Based on the patterns they identified, the team concluded that both public and private coverage of liquid biopsy tests appears to have grown significantly in recent years, though some notable limitations remain, including policies that restrict testing to specific genes or endorse only certain branded test technologies.
CtDNA liquid biopsy technologies entered the cancer testing market relatively recently, with Guardant Health leading the field with its 2014 launch of the Guardant360 multi-gene sequencing test. In the intervening years, the use of this and other similar or analogous assays has increased rapidly.
In their study this week, the UCSF researchers wrote that the growth and adoption of such tests is expected to increase even further. And considering that payor coverage for genomic medicine is an important determinant of testing access, and in turn, precision medicine access, they hoped to try to uncover trends in how coverage decisions have tracked with this rapid expansion in technology.
According to the authors, their analysis showed that coverage of ctDNA-based cancer testing increased over the four-year period studied, with the trend in both private payor and Medicare coverage showing more policies, more positive policies, and a broadening of the scope of coverage across policies.
Although the Canary Insights Database does not include all policies from all private payors in the United States, the authors noted that it does include more than 200 payors and enables an analysis of policies that apply to about 75 percent of the US population.
As of mid-2019, the researchers found that a total of 65 private payors and 4 MACs had published policies about ctDNA testing. No payors in the database provided coverage for liquid biopsies at the start of 2016, but by mid-2019 the coverage rate had risen to 38 percent.
Medicare policies specifically expanded from no LCDs for the use of ctDNA-based cancer panel tests in 2017 to eight final LCDs, two draft LCDs, and two future effective final LCDs in 2019. Although there have not yet been any NCD policies issued explicitly providing coverage for ctDNA-based panel tests, CMS's NCD on sequencing for advanced cancer includes ctDNA-based panel test coverage if the test is FDA-approved. There are currently no FDA-approved ctDNA-based panel tests, but several companies, including Guardant Health, Foundation Medicine, Personal Genome Diagnostics, and Resolution Biosciences, have said they are bringing their products through FDA review.
Study authors also reported that individual coverage policies appeared to become more expansive from 2017-2019. In terms of tumor types covered, for example, there was a shift from just a single type (non-small cell lung cancer) to 12 solid and hematologic cancers by the end of the study period. Early coverage decisions, which were limited to a single gene, EGFR, have also transitioned to current coverage of multi-gene tests like Guardant's 73-gene panel.
Alongside this, the study found that policies for liquid biopsy have trended in recent years from mainly cancer-specific indications to more agnostic use, mirroring the increasing emphasis on pan-cancer genotyping that has occurred for more traditional, tissue-based genomic tests.
According to the authors, Medicare LCDs issued earlier in the study period were written to address specific brand-named tests only for particular cancer types. "For example, four MACs issued final LCD policies in 2018 for the Guardant360 ctDNA-based panel test for NSCLC, and the same four MACs issued final LCD policies in 2019 for the InvisionFirst ctDNA-based panel test [marketed by Inivata] for NSCLC," the group wrote.
But by early 2019, the same four MACs had issued draft LCD policies that would provide pan-cancer coverage in 12 solid tumors. These more recent coverage proposals are still brand-specific, namely for Guardant360, but "the move toward pan-cancer coverage is significant," the authors wrote.
"We think that the increased coverage, especially Medicare coverage of pan-cancer use, will expand the use of liquid biopsy in clinical practice in the future," Michael Douglas, a researcher at the UCSF Center for Translational and Policy Research on Personalized Medicine and a lead author of the study, said in a statement accompanying the JNCCN publication. "The hope is that results in more targeted care with better treatment and diagnostic options, leading to long-term benefits."
Amid an overall progressive trend, the study also identified patterns in liquid biopsy coverage policies that they said illustrate notable challenges or limitations for broadened access and adoption. "Given that genomic medicine is rapidly changing, payers and policymakers will need to continue to evolve policies to keep pace with emerging science and standards in clinical care," the group wrote.
Among examples of specific hurdles, the study found that despite increasing coverage for ctDNA panel testing, individual policies largely tended to be written with "carefully defined and limited clinical scenarios," for example, for single-gene analysis only, or for specific brand-name tests.
Most private payor policy coverage remains highly specific, the group wrote, with about 87 percent of policies limited to non–small cell lung cancer, 47 percent endorsing only EGFR gene testing, and 79 percent covering only specific brand-name tests, including the Roche cobas EGFR Mutation Test v2, Guardant's Guardant360, and Sysmex Insotics' OncoBEAM.
The group also identified a significant number of payors with specific policies against coverage of comprehensive genomic ctDNA tests. Within the database 28 payors (22 of which were Blue Cross Blue Shield Association plans) had released a positive coverage policy by mid-2019. In contrast, 45 insurers, including 25 BCBSA plans, had put in place negative coverage policies.
Meanwhile, a majority of payors haven't taken steps to officially endorse or deny coverage for ctDNA sequencing panels. Only 33 percent of private payors in the database had released any policy, negative or positive.
Authors highlighted the complexity and heterogeneity of coverage as well, especially among private payors, noting that this variation may contribute to roadblocks in patients obtaining and benefitting from blood-based genomic testing.
"Private payors vary greatly in how they develop and structure their coverage policies, [and] such variation increases the challenges in assessing and tracking coverage policies and may make it difficult for patients and providers to understand relevant policies," the group wrote.
Discussing the findings, the authors added that they saw evidence in their analysis of a "conundrum" between what a test actually evaluates, "what the payor is willing to cover, and the information that the clinician receives and can use to guide clinical decisions."
"Several payors provide coverage for multigene tests but only allow the analysis of a single gene from those tests," the group wrote. "A clinician can order a particular test that interrogates 73 genes … but the payor will cover that test only for analysis of the single EGFR gene (43 percent of payors provide coverage in this manner). … In addition, limited policies, or having no policy, may burden clinicians with prior authorization requirements and appeals and thus delay or prevent access to testing."
Finally, the investigators highlighted that while coverage policies so far have been primarily for treatment selection, there are now a handful that also include monitoring indications.
"We expect that coverage may eventually be added for additional clinical indications, such as monitoring of minimal residual disease after definitive therapy or for detecting recurrence, although payors may be reluctant to adopt these indications because this would expand use to more extensive serial testing over time and thus may greatly increase costs," the authors wrote.