Early experiences with Isoniazid Preventive Therapy roll-out in an ART programme : a pharmacist's perspective.

Abstract

Tuberculosis (TB) remains the leading cause of mortality amongst people infected with Human Immunodeficiency Virus (HIV). Additionally, TB recurrence after successful treatment completion occurs more frequently amongst HIV positive people. Isoniazid provided as part of isoniazid preventive therapy (IPT) has been the gold standard of TB preventive therapy provision for the last few decades. IPT has been recommended by the World Health Organisation (WHO) and implemented by national health programmes in countries across the world. Despite global efforts and campaigns to promote IPT, uptake still remains a challenge and, progress in the operational scale- up of IPT is slow. Both international and in-country guidelines have advanced to recommending the use of IPT in HIV infected patients who have previously been treated for TB because these patients remain at risk for recurrent TB especially in TB endemic settings. However, there still remains a paucity in data on the successful programmatic use of IPT secondary to previous cured TB among HIV infected patients and is the focus of the current analysis from a pharmacists’ perspective. Methods: A retrospective secondary analysis was conducted from October 2009 to October 2013, amongst HIV infected patients, previously treated for TB, accessing HIV care at the urban CAPRISA clinical research clinic in Durban, South Africa. The aim of the study was to evaluate the implementation of Isoniazid Preventive Therapy (IPT) within the parent study titled “TB recurrence upon treatment with HAART” (TRuTH). Data was collected on IPT uptake, course completion, drug toxicity, treatment interruption, and the occurrence of incident TB either during treatment or post IPT completion. The multidisciplinary team approach in providing IPT to at risk HIV infected patients, including the specific role of the pharmacist, was also assessed. Results: There were 402 patients enrolled in the parent study. Of these 344 (85.6%) were eligible to receive IPT and of whom 212 (61.6%) initiated IPT. Among those that commenced IPT, 184 (86.8%) completed the six-month course, 24 (11.3%) permanently discontinued IPT and of these, 3.8% discontinued due to side effects. More women (n=130; 61.3%) were initiated on IPT (p=0.001) than men. Overall median adherence to IPT was 97.6% (IQR: 94.2 - 99.4). There were 22 cases of incident TB in this cohort: 13 occurred prior to IPT and nine after IPT (incidence rate ratio 0.67; 95% CI 0.29- 1.58; p=0.362). CONCLUSIONS: Overall, we demonstrated a successful IPT roll-out in a high TB endemic setting with good uptake of IPT, minimal course interruptions or side effects reported. IPT is a safe and tolerable TB prevention intervention within ART programmes and importantly amongst patients on ART with previous TB treatment experience. The pharmacist played an important role in continuum of care in IPT provision within an ART programme. This role included ensuring stable supply chain management, supporting clinic staff in monitoring safe IPT use and provided data on IPT course completion rates