This post has been updated to include information from Barron's.

By Kirell Lakhman

The FDA on Monday dealt Sequenom a blow to its plan to market its SEQureDx Down syndrome test as an LDT after it sent a letter to the company that the assay, as it currently appears, meets the definition of a medical device.

The letter was one of 14 the agency sent that day, mostly to consumer genetics firms as part of its struggle to wrangle these companies into regulatory submission.

Sequenom was the only non-DTC genetic test maker on the list.

"It has come to our attention that you are currently marketing the SEQureDx, a prenatal genetic diagnostic technology, intended to enable the detection and analysis of circulating cell-free fetal nucleic acids in a pregnant woman's blood sample for fetal gene and chromosome abnormalities," the FDA said in its letter, which can be seen here.

The letter, dated July 19 and addressed to Sequenom CEO Harry Hixson, said the SEQureDx "appears to meet the definition of a device," which means the company will need to seek FDA approval for the test — a time-consuming and costly endeavor — or convince the agency otherwise.

Trouble is, Sequenom hasn't even begun selling the assay. In fact, the company is still collecting clinical samples for studies, according to its first-quarter earning report.

And Sequenom's clinical lab says the test is "is in development."

Sequenom is on the West Coast, so I'll contact them later today. An FDA official wouldn't comment beyond what's in the letter.

'Brightened Attitude'

Now, you might think a letter like that would cause shares in Sequenom to nosedive — as if the company didn't have enough to worry about the trisomy 21 test.

But to the company's rescue today comes Ladenburg Thalmann analyst Kevin Degeeter, who raised his rating on the stock to 'Buy' from 'Neutral,' causing the stock to jump 2.3 percent, or $.13, at $5.82 in late-morning trading.

The shares have since settled down.

According to Barron's, Degeeter’s "brightened attitude" is due to chats he had with attendees of the International Society for Prenatal Diagnostics conference in Amsterdam last week, where Dennis Lo, the Sequenom science advisor who helped develop the Down Syndrome test, gave a presentation.

Barron's said DeGeeter “believes the test has the potential to offer sensitivity in clinical practice of greater than 95 percent.” He added that when Lo published his data “in the next several months,” followed by Sequenom’s own data in the first quarter of 2011, will cause “catalysts” for the shares.

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