Post-marketing experience with nevirapine extended release (XR) tablets: effectiveness and tolerability in a population-based cohort in British Columbia, Canada

BACKGROUND

Nevirapine 400 mg extended release tablets (nevirapine-XR) are a once-daily alternative to nevirapine 200 mg immediate release tablets (nevirapine-IR). Study objectives were to describe the effectiveness and tolerability of nevirapine-XR in clinical practice and, for patients who switched from once daily 2×200 mg nevirapine-IR to nevirapine-XR, compare virological suppression and plasma nevirapine concentrations during each treatment period.

METHODS

HIV-1-infected adults entered the study cohort if they initiated nevirapine-XR in British Columbia (BC) Canada between 1 April 2012 and 30 September 2012 and were followed until 30 September 2013. Demographic and clinical variables were abstracted from the BC Centre for Excellence in HIV/AIDS databases. Patients who switched from once daily nevirapine-IR to nevirapine-XR were monitored for 6 months pre- and post-switch with comparison of virological suppression (McNeamer's test) and median random plasma nevirapine concentrations (Wilcoxon-Mann-Whitney test) in each period.

RESULTS

The 536 nevirapine-XR-treated patients were 96% male, median (IQR) age 49.9 (44.0-56.9) years. Median follow-up was 15.6 (14.7-16.5) months, with 474/536 (88%) maintaining virological suppression. Emergent drug resistance developed in 5/536 (1%), adverse drug reactions in 17/536 (3%) and, although 31/536 (6%) reported 'whole' tablets in their stools, this was not associated with adverse outcomes. Among the 305 patients who switched from nevirapine-IR to nevirapine-XR, median (IQR) random plasma nevirapine concentration was higher during nevirapine-IR 5,000 (3,690-6,090) ng/ml than nevirapine-XR 3,930 (3,050-5,150) ng/ml (P<0.001), but there was no difference in virological suppression, 89% and 87% respectively (P=0.414).

CONCLUSIONS

This post-marketing study affirms the effectiveness and tolerability of nevirapine-XR as an alternative to nevirapine-IR in adults.

Single-use autoinjector for once-weekly intramuscular injection of IFNβ-1a

INTRODUCTION

IFNβ products and glatiramer acetate are established treatment first-line options in long-term disease-modifying therapy of multiple sclerosis (MS). These self-injectable medications are used once weekly to once daily. Injection-related issues are common patient-cited reasons for nonadherence. Autoinjectors have been shown to support long-term adherence to injectable medications. The ability to self-inject in MS patients has been associated with a reduced risk of missed injections and drug discontinuation, and a beneficial effect on patient independence.

AREAS COVERED

The recently introduced easy-to-use prefilled once-weekly pen is a safe and effective device for intramuscular (IM) IFNβ-1a application and provides a convenient method for self-injection. We reviewed the available published evidence on the characteristics of this device. The once-weekly pen facilitates self-injection and was preferred over prefilled syringes by patients in a prospective open-label, multicenter Phase IIIb trial in MS patients who had been using IM IFNβ-1a in prefilled syringes.

EXPERT OPINION

The simple and safe handling, shielded short needle, single-use disposable design and virtually painless injection by the device may contribute to adherence, quality of life and independence in patients using IM IFNβ-1a.