08.11.17

Photo: Tonny Foghmar

In the future it may be possible for pregnant women to avoid a placental biopsy. A simple blood test will be able to provide the same detailed information about the foetus, new research from Aarhus University Hospital and the company ARCEDI Biotech in Denmark shows.

Many pregnant women are worried if they have a high risk of carrying a foetus with Down syndrome and are offered a placental biopsy. Now these women may soon stop worrying about this test. A new prenatal diagnostic method, based on a simple blood test, targeting rare fetal cells circulating in maternal blood, is currently being implemented at Aarhus University Hospital in collaboration with the biotech firm ARCEDI Biotech.

For some years, researchers have tried to find an alternative to invasive tests such as a placental biopsy, where cells are extracted from the placenta. These tests carry a minor risk of miscarriage of approximately 0.2%.

The focus of the new test is to find foetal cells in the blood to provide the same information as cells from the placenta. For years research groups around the world struggled to find these rare foetal cells in the maternal blood. The Danish company ARCEDI Biotech and Aarhus University Hospital have collaborated for the last 12 years to find a solution and now they seem to have succeeded.

New test with huge potential

The scientific article, recently published in the acknowledged international journal Prenatal Diagnosis, presents five cases with different chromosomal abnormalities present in the foetus, that were picked up by ARCEDI’s new technology.

- This test has a huge potential. It can not only detect a foetus with Down syndrome, but also smaller chromosomal abnormalities, which may lead to severe syndromes, says Ida Vogel. She is a consultant at Department of Clinical Genetics and Centre for Prenatal Diagnostics at Aarhus University Hospital.

The test will be implemented in 2018

As a part of a research project, the new test is now being offered at Aarhus University Hospital and several regional hospitals to pregnant women not opting for a placental biopsy. The purpose is to find out if the blood test detects the same chromosomal abnormalities as the invasive placental biopsy.

The plan is to introduce the test in daily clinical practice all over Central Denmark Region from the beginning of 2018.

- I still think it will take a few years before we can avoid invasive tests, says Niels Uldbjerg, consultant and professor at Department of Obstetrics and Gynaecology, Aarhus University Hospital.

- But if the price is fair, the blood sample could be implemented as a screening test, offered to all pregnant women. This is the ultimate goal.

The price is a decisive factor. Today, the price is almost the same for the placental biopsy and the blood based prenatal test. When the analysis is tested in larger scale, ARCEDI Biotech will start to focus on reducing the costs.

Facts

• 95% of all Danish pregnant women accept the offer for an ultrasound examination and a blood test in gestational week 12. Based on these tests, the risk of carrying a foetus with Down syndrom is calculated.
• If the risk is higher than 1:300 the pregnant woman is offered a placental biopsy or a blood test called NIPT (non-invasive prenatal test)
• The placental biopsy can identify a large number of chromosomal abnormalities and thus a number of severe syndromes. The placental biopsy carries a risk of miscarriage of 0.2%. Detection of no chromosomal abnormalities provides the highest likelihood of a healthy foetus
• NIPT is an alternative to the placental biopsy. It is a blood sample taken from the pregnant women carrying no risk of miscarriage. Today, NIPT can only provide a risk estimate for carrying a foetus with Down syndrome or not. It can detect less than the placental biopsy and the result is not definitive. Therefore, a placental biopsy should be made in case of abnormal NIPT results
• The new blood test mentioned in this press release is called a cell-based NIPT. This test is based on foetal cells and provides more information about the genetic status of the foetus than the original NIPT. This cell-based NIPTcan detect Down syndrome and a number of chromosomal abnormalities.

Behind the research result

• Study design: Basic research and translational research (where research is translated to patient care).
• The study is made in a collaboration between: The biotech firm ARCEDI Biotech, researchers and clinicians at Department of Obstetrics and Gynaecology and Department of Clinical Genetics at Aarhus University Hospital.
• External financing: The project is financed by ARCEDI Biotech.
• Conflicts of interest: Niels Uldbjerg has received research support from ARCEDI Biotech, but not personal funding.
• Link to scientific article: http://onlinelibrary.wiley.com/doi/10.1002/pd.5150/abstract?campaign=wolacceptedarticle   

Further information

Ida Vogel, Consultant, Department of Clinical Genetics and Centre for Prenatal Diagnostics at Aarhus University Hospital, e-mail: idavogel@rm.dk, Tel.: +45 31 52 31 56.

Niels Uldbjerg, Consultant and Professor, Department of Obstetrics and Gynaecology at Aarhus University Hospital, e-mail: uldbjerg@clin.au.dk, Tel.: +45 20 67 94 20.