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The purpose of this work was to develop a formulation method to produce high quality inhalable dry powder, to formulate an anti-fibrotic small molecule tilorone to a respirable form, and to assess its anti-fibrotic potential in pulmonary administration. The aerosol flow reactor method was used to produce carrier-free formulations of water soluble and insoluble drugs as well as combination powders with drugs of opposing solubilities. L-leucine, L-valine and L-phenylalanine were studied for coating and encapsulation of drug particles. L-valine and L-phenylalanine were found unsuitable for formulation of inhalable dry powder, but the studies confirmed L-leucine’s high potential as an excipient. The produced formulations were tested for their aerosolization properties, cytocombatibility and drug permeation properties. All leucine coated powders showed good aerosolization performance. They were shown to perform flow rate independently in terms of emitted dose and fine particle fraction. In addition the doses were shown to be repeatable with coefficient of variance of the emitted dose being ≤ 0.11 for every formulation at least with one of the tested inhalers. The fine particle fractions were 28-49% when mannitol was used as matrix former and 54-70% when cyclodextrin was used instead. Water insoluble beclomethasone dipropionate in combination powder was found to have significantly faster permeation through a lung cell monolayer when compared to physical mixture of the formulation components. Similar difference was not seen with water soluble salbutamol sulphate. The effect was not observed with cyclodextrine based formulations of prednisolone and fludrocortisone-21-acetate.The anti-fibrotic water soluble small molecule tilorone was formulated and its anti-fibrotic potential was studied in vivo. The produced formulation showed flow rate independent emission and fine particle fraction when emitted from Easyhaler® at flow rates of 40 and 55 Lmin-1. The emitted doses were 3.0 mg for both flow rates with fine particle fractions being 28% and 30% for 40 and 55 Lmin-1 respectively. The formulation was shown to retain its biological activity in vitro after the processing despite high reactor temperatures. Tilorone was studied in pulmonary administration in a silica model of pulmonary fibrosis in mice. It produced significant reduction in histological scoring of fibrosis when compared to the vehicle group. The effectiveness of tilorone in pulmonary administration could likely be increased with more refined dosing. In this thesis we have shown that the aerosol flow reactor method is a versatile mean for formulating both water soluble and insoluble drugs. We have shown that tilorone can be formulated as inhalable dry powder andhas high potential in treatment of fibrotic lung diseases. LK Ville Vartiaisen väitöskirjatyössä Helsingin yliopiston kliinisessä tutkijakoulussa tutkittiin antifibroottisten lääkeaineiden keuhkoannostelua. Tutkimuksen tavoitteena oli kehittää menetelmä korkealaatuisten hengitettävien kuivajauheiden tuottamiseen antifibroottisista molekyyleistä, formuloida antifibroottinen lääkeaine tiloroni hengitettävään muotoon sekä tutkia sen antifibroottista potentiaalia paikallisessa keuhkoannostelussa. Kehitetyllä menetelmällä kyettiin molempien kliinisessä käytössä olevien keuhkofibroosilääkkeiden lisäksi formuloimaan uusi antifibroottinen molekyyli tiloroni keuhkoihin annosteltavaksi kuivajauheeksi. Tutkimuksessa todettiin tiloronin olevan tehokas myös paikallisesti keuhkoihin annosteltuna. Tutkimuksessa käytettiin aerosolireaktorimenetelmää tuottamaan aminohapoilla päällystettyjä lääkeainehiukkasia. Päällystysmateriaaleina käytettiin L-leusiinia, L-valiinia ja L-fenyylialaniinia. L-valiini ja L-fenyylialaniini eivät soveltuneet hengitettävien kuivajauheiden tuottamiseen, mutta kokeissa vahvistettiin jo aiemmin havaittu L-leusiinin suotuisa vaikutus jauheiden valuvuuteen ja aerosolisoitumiseen. Lääkeainehiukkasista tuotettujen jauheiden sopivuutta keuhkoannosteluun tutkittiin inhalaatiosimulaattorilla. Inhalaatiosimulaatioissa L-leusiinilla päällystetyt jauheet aerosolisoituivat hyvin ja annokset olivat toistettavia. Sisäänhengityksen voimakkuus ei merkittävästi vaikuttanut aerosolisoitumiseen tai annoksiin. Formuloinnin vaikutusta lääkkeiden kalvoläpäisevyyteen tutkittiin yksikerroksisen solukalvon läpi. Solujen annettiin erilaistua ilma-neste-rajapinnassa, jolloin ne muodostivat tiiviit liitokset ja värekarvoja kuvaten keuhkojen pintasolukkoa. Rasvaliukoinen beklometasonidipropionaatti läpäisi keuhkosolujen muodostaman solukalvon selvästi nopeammin mannitolin ja L-leusiinin kanssa formuloituna kuin näihin sekoitettuna. Vastaavaa eroa ei havaittu vesiliukoisilla salbutamolisulfaatilla ja tiloronilla tai syklodekstriinipohjaisilla formulaatioilla rasvaliukoisista prednisolonista ja fludrokortisoni-21-asetaatista. Tiloronin tehoa keuhkofibroosiin paikallisessa keuhkoannostelussa tutkittiin piidioksidille altistetuilla hiirillä. Piidioksidilelle altistettuina hiiret kehittävät idiopaattista keuhkofibroosia matkivan etenevän läiskittäisen fibroosin. Kokeissa paikallisen annostelun osoitettiin johtavan tilastollisesti merkitsevään fibroosin vähenemiseen. Tutkimuksessa todettiin aerosolireaktori n sopivan kemiallisesti erilaisten lääkemolekyylien formulointiin ja vahvistettiin L-leusiinin asema soveltuvana materiaalina lääkeainehiukkasten päällystämiseen. Lisäksi osoitettiin tiloronin olevan formuloitavissa hengitettävään muotoon ja vähentävän fibroosin muodostumista myös paikallisesti keuhkoihin annosteltuna. Tutkimustulosten perusteella Euroopan komissio on myöntänyt tiloronille harvinaislääkestatuksen idiopaattisen keuhkofibroosin hoitoon.

Drug delivery via the pulmonary route has increasingly received much attention in recent years. Inhalable particles that are capable of reaching the deep lungs for the intended application can be achieved by particle engineering methods and use of appropriate inhalation device. This study seeks to develop a carrier-free formulation for poorly water soluble drugs with desirable aerosol properties for pulmonary therapy. The Active Pharmaceutical Ingredients (APIs) used in this work, Pirfenidone and Budesonide are treatment drugs for some pulmonary diseases hence their delivery via the pulmonary route will be better suited for fast local action. Carrier-free drug powders were formulated using particle engineering methods to achieve the desirable aerosol properties for inhalation therapy. The aerosol flow reactor method was utilized in this study and the leucine coating on the powder particles were formed by physical vapour deposition of leucine. Prior to the aerosol flow reactor step, precursor solutions were prepared with varying concentrations of leucine and also an exogenous surfactant, Dipalmitoylphosphatidylcholine (DPPC). The precursor solutions were prepared by wet milling of leucine and DPPC in ethanol. The drug was then added to the milled suspension to get the precursor solution ready for the aerosol process. In the aerosol flow reactor, the leucine formed nanocrystals which were deposited onto the dried drug particles by physical vapour deposition (PVD). Two poorly-water soluble drugs were formulated using varying leucine concentrations and the resulting powders were investigated with different inhalers for their aerosolization behaviours. The morphologies of the coated fine powders were also studied by scanning electron microscopy. Pirfenidone powders showed agglomerated particles with the degree of agglomeration increasing with decreasing leucine concentration. This made the powders less flowable and dispersible, but the deagglomeration principle of the inhalation device improved the aerosolization properties. The powder with less leucine content had agglomerates which were rather difficult to separate even with the inhalation device’s deagglomeration principle. The particle size distribution was much higher and most likely to be too large for inhalation. The Budesonide particles, having sustained the heat in the aerosol flow reactor showed much spherical particles with minimal surface contact. The powders showed good aerosolization properties for deep lung deposition. The particle size distributions of all Budesonide powders with leucine coating were also well within the appropriate inhalable range.