TDF Long Term Study

TDF is a nucleotide reverse transcriptase inhibitor (NRTI) which can be taken only once per day and continues to have good efficacy even in patients who have resistance to other NNRTI in the absence of K65R mutation. TDF is a choice for patients with NRTI resistance, or those that require once-daily regimen to improve adherence. Currently, TDF has not been approved by the US FDA for children less than 18 years, but pediatricians has been using TDF in children who have treatment failure because of limitation of a more appropriate pediatric ARV. The Thai national guideline for pediatric 2009 recommend the use of TDF in children who have failed the first line therapy with multi-NRTI mutation and are more than 30 kilograms or have tanner stage 4 or more. However, the problem is that there is no pediatric TDF formulation. The available preparation of 300 mg tear drop tablet, if cut in half, may increase dosing errors, more or less by 18-37%. This will affect the blood level and/or toxicities. Therefore, the Thai Governmental Pharmaceutical Organization (GPO) has produced a generic TDF formulation that can be used in HIV-infected children. This study will assess the safety and efficacy information in children using this generic pediatric TDF formulation.

Inclusion criteria

• children who are changing to TDF due to adherence problem or treatment failure
• children who are already on TDF due to their clinical indication

Exclusion criteria

• child/caretaker refuse to participate in this study
• cannot adhere to the study schedule