RT Journal Article SR Electronic T1 In vitro evaluation of the Twincer colistin dry powder inhaler as a non-cough-inducing alternative to Colobreathe JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP PA2561 DO 10.1183/13993003.congress-2016.PA2561 VO 48 IS suppl 60 A1 Hagedoorn, Paul A1 Grasmeijer, Floris A1 Hoppentocht, Marcel A1 Akkerman, Onno A1 Frijlink, Henderik A1 de Boer, Anne YR 2016 UL http://erj.ersjournals.com/content/48/suppl_60/PA2561.abstract AB Background: patients prefer dry powder inhalation to nebulisation but the Colobreathe dry powder inhaler for colistimethate sodium (CMS) is not well appreciated in the Netherlands for a number of different reasons, including serious cough problems by some patients after inhalation of the drug.Aim: to assess the suitability of the Twincer as alternative to the Colobreathe for patients having problems with this capsule based inhaler.Methods: in vitro evaluation of the Twincer (55 mg) and Colobreathe (125 mg) was performed using the Next Generation Impactor and a laser diffraction apparatus (Sympatec HELOS) operated at 4 kPa (inhalation volume: 4L; n = 3).Results: laser diffraction analyses shows a finer aerosol from the Twincer than from the Colobreathe. Delivered CMS doses and fine particle doses (FPFs 1-5 µm) from Colobreathe were 126 mg (+14.7/-31.9 mg) and 25.5 mg (+2.8/-3.5 mg) respectively versus 48.5 mg (+2.9/-3.3 mg) and 26.4 mg (+1.4/-1.2 mg) from Twincer. Capsule fragmentation and emission of capsule fragments was observed during evaluation of the Colobreathe but not for the Twincer (having the drug in an aluminum blister).Conclusions: The higher dispersion efficiency of the Twincer (FPF is 54.4% of delivered dose versus 20.2% for Colobreathe) enables to inhale a much lower dose (at lower flow rate) without capsule fragments in the aerosol. As a consequence, the Twincer is expected to be better tolerated by patients and, therefore, provides a suitable alternative to the Colobreathe. This expectation is corroborated by positive feedback from the first patients suffering from CF or non-CF bronchiectasis who received the Twincer on the basis of 'medical need'.