Dive Brief:

• FDA has greenlighted the first test to detect Fragile X Syndrome (FXS), a genetic condition that can cause mild to severe intellectual disability, developmental delay, social and behavioral issues, and autism spectrum disorder, the agency said Friday.
• Austin, Texas-based biotech Asuragen won De Novo authorization for a kit the agency said can both help diagnose the condition and assess adults who might carry the alteration to the FMR1 gene associated with the disorder.
• Separately, FDA authorized two other in vitro diagnostic tests, according to listings in its premarket approval database Monday, intended to help screen for hepatitis B and H. pylori infection, a cause of peptic ulcers.

Dive Insight:

The condition occurs in 1 in every 4,000 males and 1 out of 8,000 females, according to figures from the Centers for Disease Control and Prevention, when a DNA segment called a CGG trinucleotide repeat shows up an excessive amount on the X chromosome.

The Asuragen test measures the number of repeats of that segment in the FMR1 gene, assessing whether the amount is normal, intermediate, premutation or full mutation, FDA said — the latter usually signaling an individual has FXS. Additionally, premutation occurs in about 1 in 150 women and can mean increased risk of bearing a child with FXS. Men with a premutation can pass the premutation on to daughters, the agency said.

FDA also said the test can be used to help diagnose disorders related to FXS, including an adult movement and cognitive disorder known as fragile X-associated tremor/ataxia syndrome, as well as fragile X-associated primary ovarian insufficiency.

Regulators' evaluation of the test took about 10 months. FDA said it reviewed data from specimens at three clinical sites and diagnostic accuracy exceeded 95%. FDA specified that the test should be considered alongside an individual's family history and clinical signals of the condition, and that it's not intended to screen eggs prior to in vitro fertilization or to be used in fetal diagnostic testing.

The De Novo authorization establishes a device classification category for so-called Trinucleotide Repeat Disorder DNA Tests, whereby future products can be submitted as 510(k)s.

Also this week, in vitro diagnostic regulators at FDA announced ARJ Medical won premarket approval for a test kit and analyzer meant to detect urease associated with the bacteria H. pylori in the human stomach via breath samples, ultimately aiding in initial diagnosis of H. pylori infection, which can lead to peptic ulcers.

Likewise, global molecular and immunodiagnostics company DiaSorin gained premarket approval for an immunoassay meant to help diagnose hepatitis B in patients with symptoms or at risk of the infection. Results from the blood test may be used to help determine susceptibility to hepatitis B before or after an individual receives a vaccine, FDA said.