Screening might lower drug reaction risk: study


TAIPEI–A recent study has shown that genetic screening can help lower the risk of adverse drug reactions among epilepsy patients, a finding that represents a step forward in the application of pharmacogenomics in the clinical field, the research team from Taiwan’s leading research institute said yesterday.

The study showed that, through genetic screening, drug-induced syndromes such as Stevens-Johnson Syndrome (SJS) and Toxi Epidermal Necrolysis (TEN) can be prevented among users of carbamazepine, a drug used to treat an intense facial pain condition called trigeminal neuralgia, said Shen Chen-yang, leader of the Academia Sinica research team.

“SJS and TEN are serious adverse drug reactions that could result in death,” Shen said.

The majority of complaints received each year by the Taiwan Drug Relief Foundation, an organization that investigates the adverse effects of drugs, are from carbamazepine users, according to Shen.

“There are about 20,000 to 30,000 users of carbamazepine in Taiwan,” he said.

In the study, a total of 4,877 patients at 23 hospitals, who were taking carbamazepine, were screened for a specific genotype (HLA-B8*1502), Shen said. The 372 patients who tested positive for the genotype were given an alternative medication, while those who tested negative continued with carbamazepine, he said.

After two months of monitoring, it was found that there were no incidents of SJS or TEN among the people who had been taken off the carbamazepine, Shen said. On the other hand, 218 of the patients who remained on carbamazepine developed minor to widespread rashes, which were however unrelated to SJS or TEN, he said.

The study not only illustrated that HLA-B8*1502 screening is effective in preventing adverse drug reactions but also hinted at its usefulness in developing personalized medicine, Shen said.

“Scientifically speaking, the results of gene testing should be more precise than a record of family medical history,” Shen said.

However, at the moment, genetic screening is quite expensive and is not widely used in clinical practice, he added.

The study was published in New England Journal of Medicine on March 24.