Rapid Absorption of Naloxone from Eye Drops

Naloxone as emergency treatment for opioid overdosing can be administered via several routes. However, the available administration methods are invasive or may be associated with incomplete or slow naloxone absorption. We evaluated pharmacokinetics and local tolerance of naloxone ocular drops in healthy beagle dogs. Naloxone administration as eye drops produced fast absorption with time to maximum plasma concentration (t(max)) achieved in 14 to 28 min, high plasma exposure (C-max 10.3 ng/mL to 12.7 ng/mL), and good bioavailability (41% to 56%). No signs of ocular irritability were observed in the scored ocular tolerability parameters, and the reactions of dogs suggesting immediate ocular discomfort after the dosing were sporadic and short lasting. Slight and transient increase in the intraocular pressure and transient decrease in the tear production were recorded. The results suggest that eye drops may provide a fast and an effective non-invasive route for naloxone administration to reverse opioid overdosing, and clinical studies in the human are warranted.Peer reviewe

Rapid Absorption of Naloxone from Eye Drops

Naloxone as emergency treatment for opioid overdosing can be administered via several routes. However, the available administration methods are invasive or may be associated with incomplete or slow naloxone absorption. We evaluated pharmacokinetics and local tolerance of naloxone ocular drops in healthy beagle dogs. Naloxone administration as eye drops produced fast absorption with time to maximum plasma concentration (tmax) achieved in 14 to 28 min, high plasma exposure (Cmax 10.3 ng/mL to 12.7 ng/mL), and good bioavailability (41% to 56%). No signs of ocular irritability were observed in the scored ocular tolerability parameters, and the reactions of dogs suggesting immediate ocular discomfort after the dosing were sporadic and short lasting. Slight and transient increase in the intraocular pressure and transient decrease in the tear production were recorded. The results suggest that eye drops may provide a fast and an effective non-invasive route for naloxone administration to reverse opioid overdosing, and clinical studies in the human are warranted

Rapid Absorption of Naloxone from Eye Drops

Naloxone as emergency treatment for opioid overdosing can be administered via several routes. However, the available administration methods are invasive or may be associated with incomplete or slow naloxone absorption. We evaluated pharmacokinetics and local tolerance of naloxone ocular drops in healthy beagle dogs. Naloxone administration as eye drops produced fast absorption with time to maximum plasma concentration (tmax) achieved in 14 to 28 min, high plasma exposure (Cmax 10.3 ng/mL to 12.7 ng/mL), and good bioavailability (41% to 56%). No signs of ocular irritability were observed in the scored ocular tolerability parameters, and the reactions of dogs suggesting immediate ocular discomfort after the dosing were sporadic and short lasting. Slight and transient increase in the intraocular pressure and transient decrease in the tear production were recorded. The results suggest that eye drops may provide a fast and an effective non-invasive route for naloxone administration to reverse opioid overdosing, and clinical studies in the human are warranted

Laajentavien tilojen eläinaineksen hankinta

Opinnäytetyön tavoitteena oli selvittää investoineiden tilojen eläinaineksen hankinnan suunnittelua ja toteutusta, ja löytää keinoja onnistuneen hankinnan toteuttamiseen. Työn tilaaja on Oulun seudun ammattikorkeakoulun Luonnonvara-alan yksikkö ja se tehtiin yhteistyössä Verkostot nautakarjatalouden edistäjinä - hankkeen kanssa. Investoivat tilat kasvattavat eläinmäärää keskimäärin kaksin- tai kolmenkertaisiksi, ja vaihtoehtoja hankintamenetelmiksi on useita. Toimivien keinojen löytäminen auttaa investoinnin onnistumisessa ja tuotannon nopeassa käynnistämisessä. Selvitys tehtiin haastattelemalla jo investoineita maatilayrittäjiä. Haastattelujen pohjalta etsittiin hyviä käytäntöjä eläinten hankintaan. Haastattelut suoritettiin tilakäynneillä. Kohdetiloista eläinten hankinnassa onnistuivat parhaiten ne, jotka aloittivat prosessin ajoissa ennen uuden rakennuksen valmistumista. Suunnitelmallisuus auttaa tuotannon nopeassa käynnistämisessä ja joustava aikataulu edesauttaa laadukkaan eläinmateriaalin etsinnässä. Parhaimmat tulokset saadaan hankkimalla eläimet vasikoina tai hiehoina. Jatkossa aiheesta kannattaisi tehdä laajempi haastattelututkimus ja ohjekirja investoiville tiloille. Valmis aikataulupohja ja suunnitelmalomake auttaisivat laajentavia tiloja eläinten hankinnassa.The subject of the thesis was to clarify the planning and realization of the acquisition of the animal material of farms which have invested and find means for the realization of the successful acquisition. The subscriber of the work is the unit of Oulu University of Applied Sciences and it was made in cooperation with Verkostot nautakarjatalouden edistäjinä – project. Investing farms increase the number of animals double or three-fold on average and there are several alternatives for acquisition methods. The finding of the functional methods helps in the success of the investment and in the quick starting of the production. The report was made by interviewing farmers who already have invested. On the basis of the interviews good practices were looked for acquisition of animals. The interviews were performed with visits. In the acquisition of animals the farmers who began the process in time before the completing of the new building succeeded best. Planning helps in the quick starting of the production and the flexible schedule facilitates the search of high-quality animal material. The best results are obtained by getting the animals as calves or heifers. In the future a more comprehensive interview study and an instruction booklet would be beneficial. A schedule form and a plan form would help extending farms in the acquisition of animals

Absorption and pharmacokinetic modelling for drug development

Absorption, distribution, metabolism, and excretion (ADME) are the main processes that determine the concentration-time profile i.e., the pharmacokinetic (PK) profile of a drug in plasma and tissues. When the PK profile is further connected to relevant information concerning the pharmacodynamics of the drug, the quantitative information can be used to guide drug’s dosing selection. Therefore, it is of utmost importance to try to predict the ADME properties and the PK profile of drugs already in the drug discovery and to refine the understanding during drug development. The ADME processes are complex and dynamic biological events which make the prediction challenging. Despite promising progress during recent years, there is still a lot to do in improving the in silico and in vitro tools for predicting drug PK in human particularly absorption and metabolism. In addition, the ADME properties should not be considered too much in isolation. The ADME properties need to be bound together to produce a quantitative estimate of the drug’s PK profile in human. This requires using the PK modelling techniques. Therefore, continuous development of models predicting individual ADME properties as well as better PK modelling methods are needed. Also, retrospective analysis of the models with in vivo data is an essential part of developing and refining the models. In this thesis, in silico and in vitro models for predicting the passive absorption of drug candidates were developed. Novel quantitative structure property relationship (QSPR) models were built to predict the absorption rate constant (Ka) of drugs in human based on calculated physicochemical molecular descriptors. The paracellular absorption route of in vitro cell line models were characterised and means to scale the Caco-2 in vitro permeability results to human intestine was found. The developed absorption models can be used in the early drug discovery to guide molecule design and to select the most promising compound for further studies. Rapid and complete absorption alone is not enough but metabolism must also be taken into account when predicting the bioavailability of the drug and the possibility of achieving an effective plasma concentration. In this thesis two strategies to overcome extensive drug metabolism were studied namely ocular topical administration route for naloxone and inhibition of metabolism with co-administered drugs for levodopa. All the studies of this thesis produced such data that can be used to develop PK models. As a conclusion, this thesis provided novel models for predicting the passive absorption of drug candidates and proven strategies to overcome the extensive metabolism of drugs. The findings of this thesis support the use of PK modelling techniques to guide drug development from the early discovery to late development.Imeytyminen, jakautuminen, metabolia ja erittyminen (ADME) ovat prosesseja, jotka lääkeaineen annostelun jälkeen määrittävät sen pitoisuus-aikaprofiilin eli farmakokineettisen profiilin veressä ja kudoksissa. Kun farmakokineettinen profiili yhdistetään edelleen lääkkeen farmakodynamiikkaa koskevaan tietoon, muodostunutta kokonaisuutta voidaan käyttää ohjaamaan tehokkaan ja turvallisen annostelun valintaa. Tämän vuoksi on hyvin tärkeää yrittää ennustaa lääkeaineen ADME-ominaisuuksia ja farmakokineettistä profiilia jo lääketutkimuksen varhaisessa vaiheessa ja tarkentaa tätä ennustetta sitä mukaan, kun tiedon määrä lisääntyy lääkekehityksen edetessä. ADME-prosessit ovat monimutkaisia ja dynaamisia biologisia tapahtumia, mikä tekee niiden ennustamisesta haastavaa. Huolimatta viime vuosien lupaavasta edistymisestä lääkeaineen farmakokinetiikan ennustamisessa in silico- ja in vitro -työkaluin, on siinä edelleen paljon parannettavaa. Erityisesti tämä koskee lääkeaineen imeytymisen ja metabolian ennustamista. Yksittäisiä ADME-ominaisuuksia ei pidä myöskään liiaksi tarkastella erillään muista. Ne on yhdistettävä toisiinsa, jotta voidaan laskennallisesti ennustaa lääkeaineen farmakokineettistä profiilia. Tämä puolestaan ei onnistu ilman farmakokineettisiä mallinnustekniikoita. Sekä yksittäisiä ADME-ominaisuuksia ennustavia malleja että parempia farmakokinetiikan mallinnusmenetelmiä kehitetäänkin jatkuvasti. Mallien retrospektiivinen analyysi havaitun in vivo -datan avulla on olennainen osa näiden mallien kehittämistä. Tässä työssä kehitettiin in silico ja in vitro malleja lääkeaineiden passiivisen imeytymisen ennustamiseksi lääkekehityksen varhaisessa vaiheessa. Rakennettiin uusia kvantitatiivisia rakenne-ominaisuussuhde (QSPR) -malleja, joilla voidaan ennustaa lääkeaineen imeytymisnopeutta (Ka) ihmisen ruoansulatuskanavasta perustuen lääkeaineen laskennallisiin fysikaalis-kemiallisiin ominaisuuksiin. Karakterisoitiin tunnettujen In vitro -solulinjamallien parasellulaarinen läpäisyreitti ja löydettiin keino in vitro Caco-2 solukerroksen parasellulaarisen läpäisevyyden skaalaamiseksi ihmisen ohutsuolen seinämän parasellulaariseksi läpäisevyydeksi. Kehitettyjä imeytymismalleja voidaan käyttää varhaisessa lääkekehityksessä ohjaamaan molekyylien suunnittelua ja valitsemaan imeytymisen osalta lupaavimmat yhdisteet jatkotutkimuksiin. Nopea ja täydellinen imeytyminen ei kuitenkaan yksin riitä, myös metabolia on otettava huomioon arvioitaessa lääkkeen hyötyosuutta ja mahdollisuutta saavuttaa tehokas plasmapitoisuus. Tässä työssä tutkittiin kahta strategiaa voimakkaan metabolian välttämiseksi – naloksonin annostelemista silmätippoina ja levodopan metaboloivien entsyymien estämistä samanaikaisesti annettavilla lääkeaineilla. Kaikki tämän opinnäytetyön tutkimukset tuottivat sellaista tietoa, jota voidaan käyttää farmakokineettisten mallien kehittämiseen. Yhteenvetona voidaan todeta, tämän työn tuottaneen uusia malleja lääkekandidaattien passiivisen imeytymisen ennustamiseen ja todistettuja strategioita lääkkeiden voimakkaan systeemisen metabolian välttämiseksi. Tämän työn löydökset tukevat farmakokineettisten mallinnustekniikoiden käyttöä lääkekehitystyötä ohjaavina työkaluina aina tutkimuksen varhaisista vaiheista myöhäisiin kehitysvaiheisiin saakka

Quantitative determination of free and total dopamine in human plasma by LC-MS/MS:the importance of sample preparation

Background: Two methods have been developed and validated for the determination of free and total dopamine in human plasma. They are based on solid-phase extraction of the analyte from the matrix by covalent complexation with phenylboronic acid, followed by derivatization with ethylchloroformate. The derivative is quantified by reversed-phase liquid chromatography on a C18 column and positive electrospray ionization MS/MS. Results: The high selectivity obtained, in combination with the stable and relatively non-polar nature of the derivatized analyte, enables the reliable quantification of dopamine in the range 0.05 to 20 ng/ml in a 5 min run time, using only 100 mu l of sample. Total dopamine concentrations are determined (range 1 to 400 ng/ml) by including an acidic hydrolysis step, which converts the sulphate and glucuronide conjugates to free dopamine prior to extraction. The method was applied to quantify free and total dopamine levels in human plasma after dosing with the anti-Parkinson's drug combination L-dopa/carbidopa with and without entacapone. Conclusion: A sensitive and selective LC-MS/MS method has been developed and validated for the determination of free and total dopamine in human plasma. This article demonstrates how essential careful optimization of the sample preparation procedures was for developing a successful method

IMI – Oral biopharmaceutics tools project – Evaluation of bottom-up PBPK prediction success part 4: Prediction accuracy and software comparisons with improved data and modelling strategies

Oral drug absorption is a complex process depending on many factors, including the physicochemical properties of the drug, formulation characteristics and their interplay with gastrointestinal physiology and biology. Physiological-based pharmacokinetic (PBPK) models integrate all available information on gastro-intestinal system with drug and formulation data to predict oral drug absorption. The latter together with in vitro-in vivo extrapolation and other preclinical data on drug disposition can be used to predict plasma concentration-time profiles in silico. Despite recent successes of PBPK in many areas of drug development, an improvement in their utility for evaluating oral absorption is much needed. Current status of predictive performance, within the confinement of commonly available in vitro data on drugs and formulations alongside systems information, were tested using 3 PBPK software packages (GI-Sim (ver.4.1), Simcyp® Simulator (ver.15.0.86.0), and GastroPlusTM (ver.9.0.00xx)). This was part of the Innovative Medicines Initiative (IMI) Oral Biopharmaceutics Tools (OrBiTo) project. Fifty eight active pharmaceutical ingredients (APIs) were qualified from the OrBiTo database to be part of the investigation based on a priori set criteria on availability of minimum necessary information to allow modelling exercise. The set entailed over 200 human clinical studies with over 700 study arms. These were simulated using input parameters which had been harmonised by a panel of experts across different software packages prior to conduct of any simulation. Overall prediction performance and software packages comparison were evaluated based on performance indicators (Fold error (FE), Average fold error (AFE) and absolute average fold error (AAFE)) of pharmacokinetic (PK) parameters. On average, PK parameters (Area Under the Concentration-time curve (AUC0-tlast), Maximal concentration (Cmax), half-life (t1/2)) were predicted with AFE values between 1.11 and 1.97. Variability in FEs of these PK parameters was relatively high with AAFE values ranging from 2.08 to 2.74. Around half of the simulations were within the 2-fold error for AUC0-tlast and around 90% of the simulations were within 10-fold error for AUC0-tlast. Oral bioavailability (Foral) predictions, which were limited to 19 APIs having intravenous (i.v.) human data, showed AFE and AAFE of values 1.37 and 1.75 respectively. Across different APIs, AFE of AUC0-tlast predictions were between 0.22 and 22.76 with 70% of the APIs showing an AFE &gt; 1. When compared across different formulations and routes of administration, AUC0-tlast for oral controlled release and i.v. administration were better predicted than that for oral immediate release formulations. Average predictive performance did not clearly differ between software packages but some APIs showed a high level of variability in predictive performance across different software packages. This variability could be related to several factors such as compound specific properties, the quality and availability of information, and errors in scaling from in vitro and preclinical in vivo data to human in vivo behaviour which will be explored further. Results were compared with previous similar exercise when the input data selection was carried by the modeller rather than a panel of experts on each in vitro test. Overall, average predictive performance was increased as reflected in smaller AAFE value of 2.8 as compared to AAFE value of 3.8 in case of previous exercise.QC 20200930</p