of 71 patients showed.
Dr. Elena Pope
“In clinical practice, we notice that nadolol works very well in terms of controlling the size and the appearance of the hemangioma,” lead study author Elena Pope, MD, MSc, said during the annual meeting of the Society for Pediatric Dermatology. Hence, she and her colleagues were interested in comparing their clinical experience with the standard treatment with propranolol, and designed a prospective, randomized, controlled, double-blinded study, with the aim of proving that “nadolol is noninferior to propranolol, with a margin of noninferiority of 10%.”
Between 2016 and 2020, Dr. Pope and colleagues at two academic Canadian pediatric dermatology centers enrolled 71 infants aged 1-6 months with significant hemangioma that had either the potential for functional impairment or cosmetic deformity, defined as a lesion greater than 1.5 cm on the face or greater than 3 cm on another body part. Treatment consisted of oral propranolol or nadolol in escalating doses up to 2 mg/kg per day. “The blinding portion of the study was for 24 weeks with a follow-up up to 52 weeks,” said Dr. Pope, professor of pediatrics at the University of Toronto and section head of pediatric dermatology at The Hospital for Sick Children, also in Toronto. “After the unblinding at 24 weeks, patients were allowed to switch their intervention if they were not happy with the results.”
Of the 71 patients, 35 received nadolol and 36 received propranolol. The two groups were similar in terms of clinical and demographic characteristics. Their mean age at enrollment was 3.15 months, 80% were female, 61% were White, 20% were Asian, and the rest were from other ethnic backgrounds.
At 24 weeks, the researchers found that the mean size involution was 97.94% in the nadolol group and 89.14% in the propranolol group (P = .005), while the mean color fading on the visual analogue scale (VAS) was 94.47% in the nadolol group and 80.54% in the propranolol group (P < .001). At 52 weeks, the mean size involution was 99.63% in the nadolol group and 93.63% in the propranolol group (P = .001), while the mean VAS color fading was 97.34% in the nadolol group and 87.23% in the propranolol group (P = .001).
According to Dr. Pope, Kaplan-Meir analysis showed that patients in the propranolol group responded slower to treatment (P = .019), while safety data was similar between the two groups. For example, between weeks 25 and 52, 84.2% of patients in the nadolol group experienced an adverse event, compared with 74.2% of patients in the propranolol group (P = .466). The most common respiratory adverse event was upper respiratory tract infection, which affected 87.5% of patients in the nadolol group, compared with 100% of patients in the propranolol group (P = 0.341).
The most common gastrointestinal adverse event was diarrhea, which affected 66.7% of patients in both groups. One patient in the propranolol group was admitted to the hospital with pneumonia and fully recovered. The incident was not suspected to be related to the medication.
“We believe that this data backs up our clinical experience and it may offer an alternative treatment in other centers where patients experience propranolol unresponsiveness, side effects, or intolerance, or where a fast response is needed,” Dr. Pope said. As for the potential cost implications, “nadolol is cheaper than the Hemangiol but comparable with the compounded formulation of propranolol.”
Concern over the safety of nadolol was raised in a case report published in Pediatrics in 2020. Authors from Alberta reported the case of a 10-week-old girl who was started on nadolol for infantile hemangioma, died 7 weeks later, and was found to have an elevated postmortem cardiac blood nadolol level of 0.94 mg/L. “The infant had no bowel movements for 10 days before her death, which we hypothesize contributed to nadolol toxicity,” the authors wrote.
In a reply to the authors in the same issue of Pediatrics, Dr. Pope, Cathryn Sibbald, MD, and Erin Chung, PhD, pointed out that postmortem redistribution of medications “is complex and measured postmortem cardiac blood concentrations may be significantly higher than the true blood nadolol concentration at the time of death due to significant diffusion from the peripheral tissues.”
They added that the report did not address “other potential errors such as in compounding, dispensing, and administration of the solution,” they wrote, adding: “Finally, we are aware of a Canadian case of death in an infant receiving propranolol, although the cause of death in that case was unable to be determined (ISMP Canada 2016 Safety Bulletin).We agree with the authors that careful consideration of the risks and benefits of beta-blocker therapy should be employed, parents need to be informed when to discontinue therapy and that further research into the pharmacokinetics and pharmacogenetics of beta-blockers are warranted.”
Following publication of the case report in Pediatrics, Dr. Pope said that the only change she made in her practice was to ask families to temporarily discontinue nadolol if their child had constipation for more than 5 days.
The study was supported by a grant from Physician Services, Inc. Dr. Pope reported having no financial disclosures.