to differentiate itself based on what it says is a wider view of various DNA abnormalities, Kollu says. The company uses the same basic instrument to analyze DNA—Illumina’s HiSeq—but it has been tailored differently to look for about 20,000 different single nucleotide polymorphisms (SNPs) in the mom’s blood sample. The workflow is pretty simple—a clinician takes a blood sample from the mom, it gets shipped to Natera’s centralized lab in San Carlos, CA, and results are sent back to the physician and patient in two weeks.
By looking broadly at so many SNPs, Natera’s chief technology officer Jonathan Sheena says the company will be able to deliver “consistent accuracy.” So far in clinical testing of more than 1,000 samples, Natera’s test hasn’t made any “false positive” errors, and has accurately been able to detect all the chromosomal abnormalities in blood that were later confirmed by standard CVS or amniocentesis, the company has said. The latest batch of data was presented last week at the Society of Maternal-Fetal Medicine conference in San Francisco.
“We have consistent accuracy,” Sheema said in an interview in January. “We have data out there which no one else can touch.”
But no test is perfect. In the latest study of 764 samples, Natera’s test produced an inconclusive result 5.9 percent of the time, Kollu says. Possibly because of the way samples were collected, the sample didn’t yield enough of the quality DNA needed to make the call, Kollu says. When that happens in the marketplace, Kollu says, it will offer the patient a second opportunity to get the test, this time for free.
The Natera test is being marketed for its ability to specifically call out when a fetus has Trisomy 13, 18 and 21, which are otherwise known as Patau syndrome, Edwards syndrome, and Down syndrome, respectively. Natera also claims it can spot monosomy X (Turner syndrome), which doesn’t tend to display clear symptoms in newborns, but which causes problems in young children, and can be effectively managed if caught early, Kollu says.
After meeting with executives from all four major players in the non-invasive prenatal genetic testing market, and many physicians at the Society for Maternal-Fetal Medicine meeting, JP Morgan analyst Tycho Peterson wrote that the market appears poised to take off.
“In stark contrast to just a few years ago, NIPT [non-invasive prenatal genetic testing] is now widely understood and used by the maternal-fetal medicine community, which tends to be an early adopter of new technology and often sees high-risk patients,” Peterson wrote in a note to clients Feb. 18. Still, he cautioned there are “widely divergent views” among physicians about the appropriate use of the technology, particularly on whether it should be expanded beyond high-risk pregnancies and into more mainstream usage.
Natera has staffed up to about 180 employees, including 20 in its sales force, to gear up for the market push.
While the companies will seek to gain the upper hand based on their technology, their clinical data, and cost, all of the companies are up against a pretty sizable obstacle—lack of education. There are about 2,500 fetal-maternal medicine specialists in the U.S., another 2,500 genetic counselors, and about 40,000 obstetrician/gynecologists that Natera wants to impress. Genetic counselors are trained to know about things like chromosomal abnormalities, and how to deal with the ethical decisions around that sort of data, but others with more classic medical training don’t necessarily speak the language.
At Natera, Kollu says he’s encountered healthcare providers who say they are unfamiliar with Trisomy 13, in which a person has three copies of genetic material on chromosome 13 instead of the usual two. And they don’t recognize it by the other name, Patau syndrome. The disorder is said to affect about 1 in every 10,000 newborns, according to the National Institutes of Health.
“They just don’t deal with it on a day-to-day basis,” Kollu says. “A typical OB/GYN gets six to 10 minutes to spend with a patient. In that time, you’ve got to make sure she’s getting enough folic acid, and other things, too. The ability of the current practitioner to process the genetic information is challenging.”
Price is bound to be a barrier as well, as the new tests are likely to make pregnancy more expensive than it already is. Natera has set up a “very broad and generous” patient assistance program to help low-income patients get the test, Kollu says. But even after paying $1,295 for the test, Natera isn’t saying patients can save further money by avoiding the standard amniocentesis or CVS tests. The Natera service should be thought of as a “screening” test that leads to further verification with one of the other diagnostic methods, Kollu says.
Confident as the company may be in its data, doing that kind of double-checking is likely to continue for the forseeable future. Nobody wants to think about getting this thing wrong. People will be making life-changing decisions based on results of this series of tests—like whether to abort a fetus with chromosomal abnormalities. The big question now for Natera and its rivals is whether millions of patients will be willing to pay premium prices for this new kind of genetic information.
