Genetic risk scores that focus on 2 single-nucleotide polymorphisms (SNPs) associated with migraines without aura might help predict patient response to triptan treatment, according to a study published in The Journal of Clinical Pharmacology.
The researchers of this study analyzed patients receiving triptan treatment for migraines without auras by calculating a genetic risk score, based on SNPs at 6 single-locus markers, and the impact triptan therapy had on headache intensity.
Patients recorded information on the intensity of migraine pain before taking the medication and then again 120 minutes later.
Based on this information, patients were categorized into either consistent responders (those with at least a 2 point decrease in pain level after the use of a triptan) or inconsistent responders (those with different results in pain levels after the use of a triptan). Peripheral blood samples were used to perform the DNA genotyping.
Of the 172 patients, 80.8% were female, 55.6% used prophylactic medication, and the average age was 38.7 years old. When comparing types of triptans used, patients not using frovatriptan (n =90) experienced a decreased chance of an inconsistent response (OR=0.548; 95% CI, 0.29-1.025; P =.060).
Logistic regression analysis showed that the rs6724624G allele had a slight association with an inconsistent response (odds ratio [OR], 2.14; 95% CI, 1.19-3.89; P =.011), but it did not remain after being corrected for multiple comparisons (false discovery rate q value =.066).
Of the 5 genetic risk score models created, GRS-2, which included the SNPs of rs6724624C and rs1024905G, had an overall response rate of 0.62 (95% CI, 0.43-0.89; P =.009) and remained inversely correlated to a risk of inconsistent response after correction for multiple testing (false discovery rate q value =.045).
Future research is needed to validate these findings, including a large prospective study to use the genetic risk score to predict outcomes, including the possibility that an inconstant response to one type of triptan does not mean there will be no response to all types of triptans.
In conclusion, using the genetic risk score including the single-nucleotide polymorphisms rs6724624C and rs1024905G “significantly improved the accuracy of discrimination between consistent and inconsistent responders” among patients using triptan therapy to treat migraines without auras.
Cargnin S, Viana M, Sances G, Cantello R, Tassorelli C, Terrazzino S. Using a genetic risk score approach to predict headache response to triptans in migraines without aura. [published online Sept. 26, 2018]. J Clin Pharmacol. doi: 10.1002/jcph.1320