OneOme recently announced a big update to the RightMed test, which included adding four new genes and nine new medications to the test. Perhaps the most significant part of this announcement was the addition of the HLA-A and HLA-B genes.
For those who don’t work in pharmacogenomics or a related industry, on the surface this update may not mean a lot to you. But the implications of this change are big, and may be important to you and/or your patients.
Identifying patients who are at an increased risk for severe skin reactions
Adding the HLA-A and HLA-B genes is significant because the RightMed test can now help identify patients who have genetic variants associated with an increased risk of severe, sometimes fatal skin reactions that are induced by certain medications.
If you have certain genetic variants in these HLA genes and you take certain medications (which include commonly prescribed medications, like allopurinol and carbamazepine), you may be at an increased risk for a life-threatening reaction called Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN). The RightMed test now provides information on your genetic risk for this particular reaction to help your provider make the most informed decision when selecting a medication for you.
Real patient impact of reporting of risk of SJS/TEN
SJS/TEN was described in one of our patient stories by Jolie, the mother of Peyton, who had SJS as a 10-year-old: “In a nutshell, SJS is the worst, most severe reaction you can have to medication next to anaphylactic shock. Your body attacks itself, and your skin literally begins to fall off. Peyton had hundreds of lesions in his mouth, and the skin on his lips peeled off,” said Peyton’s mom, Jolie Duncan.
Given the severity of SJS/TEN and our ability to provide information that may help prevent it, adding these HLA genes to the RightMed test has been a goal of OneOme’s since the very beginning. Hearing stories like Peyton’s only reaffirmed how important it was to us. The genes may only impact a handful of medications, but the evidence found between the HLA genes and the risk of these severe reactions is strong and the consequences are severe.
In fact, one study from 2016 found that mortality rates have been reported to vary between 1% and 5% for SJS and 25% to 35% for patients with TEN.2 The study also states that “early recognition and prompt withdrawal of the causative agent leads to increased patient survival.”2 We knew if we were able to play a role in mitigating this potentially fatal reaction, that it was critical that we figure out a way to add this information to our test.
With the RightMed test results, doctors get information about whether their patient is at an increased risk for SJS/TEN if they take certain medications. If the patient is at a higher risk, their doctor may choose to avoid these medications and select an alternative one to avoid a potential adverse drug reaction. By having this information available on the RightMed test report, we hope to help prevent many cases of SJS/TEN in the first place —or at least help doctors identify patients with the highest risk, so they can monitor these patients for potential side effects and reactions.
Committed to making HLA testing accessible and affordable
Although there are other laboratories offering DNA analysis for the same HLA variants as OneOme, they often come at a much higher price and are generally offered only as standalone tests. (OneOme’s RightMed test includes not only the HLA-A and HLA-B genes, but also 25 other genes.)
Arguably, the high price of these tests has reduced accessibility and contributed to the practice of HLA testing only the “highest risk” patients based on factors like ethnicity. While some HLA variants are, indeed, more common within certain ethnic populations and regions, ethnicity is a potentially dangerous and unreliable screening tool with the increasingly diverse global population. This is a paradigm OneOme is hoping to change.
From the very beginning, we made a commitment to create the most cost-effective, comprehensive pharmacogenetic test available while maintaining scientific credibility and rigor. With the addition of HLAs, patients now receive information on over 350 medications, based on the analysis of 27 genes. We are not only delivering on our mission, but also providing information that can potentially save lives.
Questions? Comment below and we’ll get back to you.