This study was conducted to explore how well enfuvirtide (T-20, Fuzeon) would be tolerated by adolescents with HIV infection. The challenge is that enfuvirtide is given, like insulin, by self-injection. Those enrolled had prior antiviral experience in at least two classes, and a viral load over 5,000. Twenty-eight adolescents (ages 12-16) participated. Thirty-two percent of the adolescents in the study were female, and roughly half were white race and half black. About 40% were of Hispanic ethnicity. Their baseline viral load was about 200,000, and their CD4 counts were about 70.

At week 24, 71% were still on enfuvirtide. There were a variety of reasons eight people discontinued prior to week 24 and only three dropped out based on refusing treatment. Adverse events linked to enfuvirtide were reported in five patients, although these were only skin infections at the site of the reaction, which is typical of the side effects attributed to enfuvirtide in the larger TORO studies.

Injection site reactions were typical of what is seen in adults as well, with 79% reporting mild or moderate reactions. As this is not a randomized study, the activity of enfuvirtide is difficult to assess here, though it has been well established in the larger TORO trials. Nevertheless, about 21% of the participants maintained at least a 1-log viral load drop at week 24 on this new regimen. There was overall a 0.6 log drop in viral load by week 24, with an increase in CD4 counts of 139 cells.

The authors conclude that, as with adults, enfuvirtide is a safe drug to use, and has a similar safety profile in adolescents as seen in adults. While the issues around injection can be a challenge, the outcomes suggest that these were manageable in a manner similar to that in adults. The impressive increase in CD4 counts is perhaps consistent with the reserve in immunologic function associated with patients of a younger age. Future studies will be reported on the use of this drug in children as well, given that there are many children who are in need of a new class to build upon for a new treatment regimen.

Reference

Abstract: 24-Week Safety and Efficacy of Enfuvirtide as Part of an Optimized Antiretroviral Regimen in Adolescents (Poster 929)
Authored by: A. Wiznia, J. Church, J. Stavola, P. Emmanuel, S. Bakshi, I. Febo, C. Cunningham, R. Lawrence, H. Gay, R. Fisher, P. Delora, L. Rowell, A. Bertasso, The T20-310 Study Group
Affiliations: Jacobi Med. Ctr., Bronx, NY; Childrens Hosp. Los Angeles, CA; Cornell Univ., New York, NY; All Children's Hosp., St. Petersburg, FL; Bronx Lebanon Hosp. Ctr., Bronx, NY; Univ. of Puerto Rico, San Juan, PR; State Univ. of New York Upstate, Med. Univ., Syracuse, NY; Univ. of Florida, Hlth. Sci. Ctr., Gainesville, FL; Univ. of Mississippi Med. Ctr., Jackson, MS; Children's Hosp. of the King's Daughters, Norfolk, VA; Roche, Nutley, NJ