Observational study shows switching to generic olanzapine safe

Genéricos/Investigación | Posted 11/09/2015 post-comment0 Post your comment

A retrospective, observational study carried out by researchers from The University of Auckland, New Zealand (NZ) found no adverse health outcomes when patients switched between generic and brand-name olanzapine [1].

MD002152

Olanzapine is an atypical antipsychotic medicine used in the management of schizophrenia and related psychoses. It has been widely available internationally since 1996, and in NZ since 1999. Before Eli Lilly’s patent expired on the originator drug, Zyprexa, in 2011, olanzapine was a relatively expensive medicine and in NZ singly accounted for more expenditure than any other medicine in 2010 (approximately NZ$30 million/year).

Charon Lessing and co-authors used data from the national pharmaceutical claims database (PHARMS), to conduct a retrospective study of all adult patients (aged 14 years or older) in NZ who had been dispensed olanzapine tablets at least five times during the six months prior to the introduction of generic olanzapine (1 June 2011) and also for the six-month period prior to 1 June 2010, i.e. one year earlier.

The majority of all patients (98.2%) had switched within three months of implementation of the pricing policy, with a further 1.5% switching within 12 months. In the one-year follow-up, 12.5% of study patients made a single switch from originator to generic drug, whilst 86% made multiple switches among generics.

This study found no increase in hospitalizations, use of the emergency department or specialist outpatient services, or untoward health events in patients following switching from Zyprexa to generic olanzapine. The study also found no changes in dosage and no increase in the mean use of additional oral or injectable antipsychotic medicines. The rate of spontaneous adverse event reporting was similar to the rate of reports for risperidone during the same 2008–2013 period and there was no increase in the expected number of deaths in this population of patients with psychotic disorders.

There was no increase in the use of healthcare services as a consequence of switching in the NZ setting. The authors therefore concluded that ‘the study suggests that a switch can be made safely from originator olanzapine to one of the available generic brands’.

Related articles
Generic olanzapine now approved in US

Another olanzapine generic hits the market

Actavis launches generic olanzapine in 11 European markets

Reference
1. Lessing C, Ashton T, Davis PB. The impact on health outcome measures of switching to generic medicines consequent to reference pricing: the case of olanzapine in New Zealand. J Prim Health Care. 2015;7(2):94-101.

Permission granted to reproduce for personal and non-commercial use only. All other reproduction, copy or reprinting of all or part of any ‘Content’ found on this website is strictly prohibited without the prior consent of the publisher. Contact the publisher to obtain permission before redistributing.

Copyright – Unless otherwise stated all contents of this website are © 2015 Pro Pharma Communications International. All Rights Reserved.

comment icon Comments (0)
Post your comment
Most viewed articles
Sobre GaBI
INICIO/Sobre GaBI Posted 06/08/2009
EU guidelines for biosimilars
EMA logo 1 V13C15
INICIO/Directrices Posted 08/10/2010