Selzentry for Children as Young as 2 Years: Details and Therapeutic Relevance

The US Food and Drug Administration has approved Selzentry for use in pediatric patients two years of age or older, who weigh at least 10 kg.

As of November 4, 2016, The US Food and Drug Administration (FDA) has approved Selzentry (maraviroc) for use in pediatric patients aged 2 years or older weighing at least 10 kg. Previously, Selzentry was approved only for use in adults aged 18 years or older.

1

Selzentry is member of a therapeutic class of HIV antivirals known as entry inhibitors. Only one other medication—Fuzeon (enfurvitide)—has a similar mechanism of action. Although both medications work by interfering with viral entry into healthy cells, until now, only Fuzeon had a pediatric indication and was approved for use in children as young as 6 years of age. Selzentry reduces the lower age limit for use of viral entry inhibitors by 4 years.

2,3

The approval of Selzentry for use in children as young as 2 years of age is based on an open-label, multicenter clinical trial codenamed A40011031 which evaluated the treatment in 103 children and adolescents aged 2 years to <18 years. Children received treatment twice daily with individualized dosing based on body surface area and whether or not the children were also receiving potent CYP3A inhibitors or inducers.

1

After 48 weeks of treatment, nearly two-thirds (65%) of children with an initial HIV-1 RNA level >1000 copies/mL experienced a reduction in HIV-1 RNA levels to <400 copies/mL. The mean increase in CD4+ cell count was 247 cells/mm

3

—a 5% increase.

1

Over the course of the trial, investigators observed common adverse reactions of vomiting (12%), abdominal pain (4%), diarrhea (4%), nausea (4%), and dizziness (3%). Most adverse reactions were mild to moderate, although 2% of patients experienced severe adverse events.

1

One adverse event varied with the formulation of Selzentry used. Through 48 weeks of treatment, patients receiving the oral solution formulation of Selzentry experienced a higher rate of gastrointestinal adverse events than patients receiving tablets—21% versus 16%. After week 48, patients were allowed to switch from the oral solution to the tablet to minimize gastrointestinal adverse events.

1

Although advances and treatment have reduced mortality rates by 80% to 90% since the introduction of protease inhibitor—containing combinations for the management of pediatric HIV infection in 1993, suboptimal control of viral levels remains an important treatment challenge. The approval of Selzentry for children as young as 2 years of age opens up an entirely new class of medications for HIV management in this population.

4

References

1. FDA. HIV E-mail updates. Selzentry Product Update. Accessed November 2016.

2. Selzentry (maraviroc) [package insert]. Research Triangle Park, NC: ViiV Healthcare; 2014.

3. Fuzeon (enfuvirtide) [package insert]. South San Francisco, CA: Genentech, Inc; 2015.

4. NIH. Guidelines for the use of antiretroviral agents in pediatric HIV infection. https://aidsinfo.nih.gov/contentfiles/lvguidelines/PediatricGuidelines.pdf. Accessed November 2016.