Pediatric Pharmacogenomics Offers Treatment Insights

Pediatric pharmacogenomics is beginning to be used in pediatric hospitals to detect impaired or heightened drug responses, and may be coming to community pharmacies.

Pharmacogenomic testing-testing for genes that can affect which drugs will work and which won’t for a given person-is already an accepted practice in many hospitals and has even arrived at retail pharmacies. Now there is pharmacogenomics testing for pediatrics, to help clinicians make the best medication choices for babies and children who have serious health conditions and even for those who are healthy now.

Genetic variables have been tied to impaired or heightened drug response in adults for many years, but the study of pharmacogenomics for children has lagged behind. Now, Translational Software Inc. (TSI) has joined with Inova Translational Medicine Institute to offer a pediatric pharmacogenomics (also called pharmacogenetics) solution and testing panel.

For adults, there is a large amount of literature and established guidelines on many of the genes that affect the response to drugs, said Houda Hachad, PharmD, MRes, chief science officer at TSI. When an adult has pharmacogenetic testing done, it is assumed that all the genes are mature and are expressing themselves fully. But some genes do not mature until later in childhood or past puberty which means that children with the same gene variants as in adults have differing responses to drugs than do adults. “You cannot always extrapolate to children from the guidelines that we have for adults,” she said.

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“We quickly saw the need to expand our analysis and literature search to identify which recommendations could be extrapolated from adults to children, and which could not,” Hachad said. “We gathered all that information and incorporated it as an additional layer before providing the interpretation.” When the testing is done, the pediatrician can be informed if there is a genotype-based approach they can use when selecting a medication or choosing a dosage, she explained.

Several hospitals are now performing pharmacogenomics testing on children with cancer or other complex conditions, Hachad noted. St. Jude Children’s Research Hospital in Tennessee now preemptively tests all children treated there whether or not they have issues with medications, with the test results stored in their medical records, she said.

Some health systems are offering pediatric gene testing to healthy children. Inova Health System hospitals are now offering pharmacogenomics testing for all newborns, Hachad told Drug Topics. “What we would like is for everybody to have that information stored early on in life, for it to be used as the baby grows.”

One drug category of particular concern for pediatric pharmacogenomics is pain relief. One of the seven actionable genes covered in the new testing is CYP2D6, which affects codeine toxicity in children, Hachad said. Antiemetic medications are another drug category where genes affect response or toxicity, she added. In addition to oncology, conditions that can benefit from this testing include sickle cell anemia and behavioral issues such as attention deficit hyperactivity disorder.

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Just as pharmacogenomics testing for adults has moved into community pharmacy, pediatric testing can, too. “A number of retail pharmacies are trying to bring this to patients and clients,” Hachad said. “It is an additional tool to their tool belt to manage complex situations and polypharmacy patients.”

All patients or their parents must have counseling when they receive any results from pharmacogenomics testing, she added. “The results need to be discussed always with a physician or a pharmacist.”