NEW YORK (GenomeWeb) – In deciding whether or not to cover noninvasive prenatal screening tests, payors place particular emphasis on evidence from clinical validation studies and recommendations from professional societies, according to a recent study.
In a study led by Andrew Dervan from the University of Washington that included collaborators from the American Institutes for Health Research, the University of California, San Francisco, and elsewhere, researchers analyzed publicly available coverage policies from 19 large US private payors regarding NIPS.
The researchers reported in Genetics in Medicine that although all 19 payors covered NIPS for trisomies 21, 18, and 13 in high-risk pregnancies, they differed in their decisions to cover sex chromosomal aneuploidies, microdeletions, and testing in average-risk pregnancies.
Patricia Deverka, a principal researcher at AIR, told GenomeWeb that the group plans to expand its analysis to NGS-based gene panels, as well as diagnostic exome and whole-genome sequencing.
One reason for starting with NIPS is that the tests have been widely adopted, and "unlike other sequencing-based panels, there's been broad and rapid coverage adoption by private payors," she said.
The study authors made use of an NGS test registry developed as part of a collaboration led by Kathryn Phillips at UCSF's Center for Translational and Policy Research on Personalized Medicine. The registry includes data on available NGS tests, including the genes analyzed, cost, and reimbursement policies.
The current registry, Payer Coverage Registry, includes policies from the five largest US private payors, which the researchers supplemented with additional analysis of coverage policies representing the top 19 payors.
Of the 19 payors, 15 had a coverage policy specifically related to NIPS, while four had more general prenatal screening policies. All 19 policies covered NIPS as a first-line assessment for trisomy 21 for women with high-risk singleton pregnancies. The payors noted that if screening for trisomy 21 is performed, then they would also cover screening for the other aneuploidies — trisomy 18 and 13.
Eight of the 19 payors had positive coverage decisions for women with average-risk singleton pregnancies.
Interestingly, all payors differentiated between the different conditions included on the tests, such as trisomy 21, 18, 13, sex chromosomal aneuploidies, and microdeletions. So, even though the commercially available tests in the US all include trisomies 21, 18, and 13 as one test, the payors considered coverage of each them separately. Most tests also include screening for sex chromosomal abnormalities, while some have the option of adding microdeletions. No payor covers microdeletion testing, while just one covers sex chromosome aneuploidy screening.
Deverka said that the fact that payors evaluated each of the indications separately could have implications for NIPS companies looking to add additional indications to their tests, as well as other developers who are looking to make large gene panels or to offer clinical exome sequencing.
"At some point it becomes impractical to look at each indication separately," she said, but "that's what the payors are doing for these tests. They're not using a different approach to look at things holistically or in the aggregate."
It is also unclear from the data how payors reimburse for tests that analyze the common trisomies as well as sex chromosomal aneuploidies and/or microdeletions, Deverka said.
The researchers also examined how the payors made their coverage decisions and what types of information they valued. In general, Deverka said, the payors placed a lot of emphasis on the companies' clinical validation studies, despite the fact that most of the studies were observational studies rather than clinical trials.
"It's certainly been the perception that the gold standard or preferred type of study is a clinical trial," Deverka said. She said that the payors were likely satisfied with the observational studies because they were "large, high-quality studies" that included prospective and case control studies. In addition, the payors cited clinical utility studies as reasons for deciding to cover NIPS, most of which were modeling studies, Deverka said.
"It suggests that payors are open to a variety of models," she said. The modeling studies that the payors cited were performed by independent technology assessment organizations like the California Technology Assessment Forum and the Blue Cross and Blue Shield Association Medical Advisory Panel, and the payors seemed to value the recommendations of those organizations. Payors also frequently cited professional guidelines in deciding whether or not to cover tests.
For instance, the American College of Obstetrics and Gynecologists and the Society of Maternal Fetal Medicine recently updated their opinion on NIPS, saying that while all patients should be able to choose NIPS, conventional screening was still the most appropriate for women with average-risk pregnancies. In addition, the organizations did not recommend the technology for microdeletion screening or multiple gestations.
The American College of Medical Genetics and Genomics, meantime, updated its policy statement this summer to say that NIPS was appropriate to screen for the common trisomies for most women, regardless of risk, and could be warranted for sex chromosomal aneuploidy screening and screening for certain copy number variants in some cases. Many test developers have expressed hope that this updated recommendation would help boost payor coverage of their tests for women with average-risk pregnancies.
Deverka noted that payors began expanding coverage to average-risk pregnancies after ACOG and the SMFM updated their policy to say that all women should have access to testing.
And, indeed, the payors themselves cited that joint statement most frequently in their policies.
The "professional guidelines are extremely important," Deverka said.
Interestingly, all payors wanted to evaluate analytical validity of the tests, but were by and large unable to, Deverka said. "They recognize that clinical sequencing is not standardized," she said, "and that procedures are application specific and not generalizable across tests." Since the payors did not have analytical validation data, Deverka said they predominantly relied on the fact that the tests were developed under CLIA regulations as well as a Blue Cross Blue Shield technology assessment report.
Deverka said that the results of this study should provide insight for test developers about how payors make coverage decisions, particularly for those developing tests in the prenatal setting.
She added that the group planned to do similar analyses for other types of NGS tests, including exome and whole-genome sequencing. In addition, she noted that while many payor policies indicated the importance of genetic counseling, especially post-test counseling, none required it as part of prior authorization.
Genetic counseling will be an important consideration for the field as it could be the source of bottlenecks for clinical implementation. There is already a shortage of genetic counselors, she said, and that issue will only be exacerbated as tests like NIPS screen for more and more rare conditions.