Plaquenil: A Possible Treatment To Congenital Heart Block Among Neonates

Pregnant women with lupus (a rheumatic autoimmune condition) have an increased risk of transmitting the condition to their newborns, especially if they have lupus or Sjögren’s syndrome along with antibodies to SSA/Ro and/or SSB/La proteins. According to Dr. Jill P. Buyon, M.D., professor of medicine and director of the Division of Rheumatology at NYU, pregnant women with lupus have a 2% increased risk of giving birth to babies with neonatal lupus, who later develop a fatal cardiac complication known as Congenital Heart Block (CHB) of varying severities (the third degree being the most severe and irreversible form of the condition).

More so, women who have had one child with CHB are at a tenfold higher risk (approximately 18 %) of having another child with the same heart condition. In Dr. Buyon’s words, “In congenital heart block, the baby’s heart beats abnormally slowly. Almost all of the affected children require permanent pacemakers before the age of 20, and some die before birth or shortly thereafter.”

When studying the statistics related to these women over the past 20 years from the national Research Registry for Neonatal Lupus, a striking observation was made by Dr. Buyon and her group of scientists: there was a reduced intake of the drug Plaquenil (hydroxychloroquine, a common drug taken by all lupus patients, and declared safe for the foetus) in mothers with children who developed CHB. This reflected a possible protective effect that the drug could exert on these babies against CHB development.

Buyon and her colleague, Dr. Peter Izmirly, M.D., designed a two-stage research study they named “Preventive Approach to Congenital Heart Block with Hydroxychloroquine (PATCH)” where they enrolled a total of 19 mothers whose first child had CHB. The primary endpoint in the initial stage of study was to observe if less than three babies were born with CHB after Plaquenil was administered. In all other cases the study was to be labelled unsuccessful. Accordingly, only one baby was born with CHB, which paved the way for setting up a bigger trial with a total of 35 women to further test the same theory.

Dr. Buyon believes that “hydroxychloroquine is very important to maintain during pregnancy to avoid a potential flare. But I think there are benefits both to the mother and to the baby, in this case.”