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Polimorfni metabolički enzimi i transportni proteini mogu značajno modulirati farmakokinetske parametre lijekova i biti razlogom nastanku nuspojava tipa A. Stoga je cilj ovog istraživanja bio ispitati nuspojave lijekova supstrata metaboličkog enzima citokroma P450 CYP2C9 i transportnog P-glikoproteina (Pgp). Na temelju retrospektivno i prospektivno sakupljenih podataka o nuspojavama lijekova supstrata CYP2C9 i Pgp procijenili smo i ulogu polimorfizama u nastanku ozbiljnih nuspojava. Iz Nacionalne baze analizirane su sve prijave nuspojava na lijekove iz razdoblja 2005. – 2011. godine. Prijave koje su sadržavale lijekove supstrate CYP2C9, CYP2C9 i Pgp, odnosno lijekove koji su supstrati transportnog proteina Pgp uzete su za analizu ako su lijekovi čiji je klirens preko navedenog enzima veći od 10%, odnosno u razmatranje su uzeti i oni čiji je klirens putem CYP2C9 između 5 i 10%, a radi se o lijekovima koji se često koriste u kombinaciji s drugim lijekovima istovremeno kao što je to primjer kod acetilsalicilne kiseline. Iz baze obrađenih prijava nuspojava odabrana je skupina od 158 ispitanika s ozbiljnim nuspojavama na lijekove supstrate metaboličkog enzima CYP2C9. Birani su bolesnici koji su razvili nuspojave na lijekove koji se najvećim dijelom metaboliziraju putem enzima CYP2C9. To su prvenstveno bili antikoagulansi kumarinskog tipa, u našoj populaciji varfarin (n=30 ispitanika), nesteroidni protuupalni lijekovi ibuprofen, indometacin, diklofenak, piroksikam (n=32), antiepileptici fenitoin, fenobarbiton i valproična kiselina (n=44), fluvastatin (n=46), te oralni antidijabetici gliburid i glibenklamid (n=6). Skupini ispitanika s nuspojavama pridružena je skupina ispitanika bez nuspojava (n=155), koja je prema dobi spolu, bolestima i konkomitantnoj terapiji odgovarala skupini s nuspojavama. Provedena je genotipizacija CYP2C9*2*3 te ABCB1 2677G>T/A, 3435C>T. Analizom Nacionalne baze za nuspojave lijekova (HALMED), te provedbom farmakogenetičkih analiza utvrđeno je: • da se nuspojave na lijekove (bez cjepiva) u više od 60% pojavljuju u žena, što je također pokazano za lijekove supstrate CYP2C9, supstrate CYP2C9 &Pgp, te supstrate Pgp • 60% svih prijavljenih nuspojava u bazi i nuspojava za lijekove supstrate prijavljene su za odrasle osobe (od 17 do 69 godina starosti) • 8% lijekova u bazi su supstrati CYP2C9, CYP2C9&Pgp ili samo transportnog proteina Pgp, a na njih se odnosi 69% svih prijava • Nuspojave iz cijele grupe lijekova supstrata CYP2C9 imaju statistički značajno više ozbiljnih nuspojava u odnosu na ostale prijave u bazi (p, Polymorphic metabolic enzymes and transport proteins can significantly modulate the pharmacokinetic parameters of medicinal products and therefore be a reason for the appearance of type A adverse reactions. The objective of this study was to test the adverse reactions to medicinal product substrates of the metabolic enzyme cytochrome P450 CYP2C9 and the transport P-glycoprotein (Pgp). Based on the retrospective and current collection of data on adverse drug reactions of the substrates CYP2C9 and Pgp, the role of polymorphism in the appearance of adverse reactions was estimated. All adverse reactions reported to the National database in the period 2005–2011 were analysed. Reports pertaining to drug substrates CYP2C9, CYP2C9 and Pgp, i.e. drugs with a substrate of the transport protein Pgp, were analysed if the drugs had a clearance via the said enzyme of greater than 10%, or if the clearance via CYP2C9 was between 5 and 10%, and there are drugs commonly used in combination with other drugs simultaneous, as is the case, for example, with acetylsalicylic acid. A group of 158 subjects with serious adverse reactions to drugs with a substrate of the metabolic enzyme CYP2C9 were selected from the adverse reactions database. The selected subjects experienced adverse reactions to drugs that were, for the most part, metabolised via the enzyme CYP2C9. These were primarily anticoagulants of the coumarin type, i.e. warfarin (n=30 subjects), nonsteroidal anti-inflammatory drugs ibuprofen, indomethacin, diclofenac, pyroxicam (n=32), anti-epileptics phenytoin, phenobarbitone and valproic acid (n=44), fluvastatin (n=46), and oral anti-diabetics glyburide and glibenclamide (n=6). In addition to the group of subjects with adverse reactions, a second group was selected of subjects without adverse reactions (n=155) and who corresponded to the adverse reaction group in terms of gender, diseases and concomitant therapy. Genotypisation of CYP2C9*2*3 and ABCB1 2677G>T/A, 3435C>T was conducted. An analysis of the National Adverse Reactions Database (kept by HALMED), and subsequent pharmacogenetic analysis established the following: • Adverse reactions to drugs (excluding vaccines) appear in women in more than 60% of cases, which has also been shown for drugs with the substrate CYP2C9, substrate CYP2C9 &Pgp, and substrate Pgp. • 60% of all reported adverse reactions in the database and adverse reactions to drug substrates were reported for adults (aged 17 to 69 years). • 8% of all drugs are based on the substrates CYP2C9, CYP2C9&Pgp or only the transport protein Pgp, while 69% of all reaction reports pertain to these drugs. • Adverse reactions from the entire group of drug substrates CYP2C9 have a statistically significant higher incidence of serious adverse reactions in comparison to other reports in the database (p

Cilj istraživanja: Cilj ovog istraživanja je kritički osvrt na literaturne podatke koji se odnose na utjecaj genskih varijanti na učinak i neželjene reakcije direktnih oralnih antikoagulacijskih lijekova. Materijali i metode: Za potrebe istraživanja i pisanja rada, od dostupnih baza podataka, pretražene su baze podataka Medline i Pubmed prema ključnim riječima: direktni oralni antikoagulansi (DOAK), dabigatran, rivaroksaban, apiksaban, edoksaban, farmakogenetika, genski polimorfizmi CES1, CYP3A4, P-glikoprotein, MDR1/ABCB1, ABCB2. Odabrani znanstveni članci obuhvaćaju sve dostupne članke iz područja farmakogenetike, farmakogenomike DOAK-a u posljednjih 10 godina, uključujući originalne znanstvene članke kao i pregledne radove koji zadovoljavaju tematiku rada. Također, u radu su prikazani slučajevi iz kliničke prakse iz rutinskog testiranja u okviru obrade pacijenata u Kliničkom bolničkom centru Zagreb u Odjelu za farmakogenomiku i individualizaciju terapije, uz poštivanje svih etičkih načela. Rezultati: Pregledom literature saznajemo da DOAK-i ovisno o metaboličkom putu stupaju u interakcije sa određenim skupinama lijekova. Jednako tako, polimorfizmi prijenosnih proteina i enzima utječu na pojavnost velikih štetnih događaja u vidu krvarenja. Zaključak: Iako su novi oralni antikoagulansi sigurni lijekovi kod većine pacijenata, ipak postoji određeni postotak pacijenata kod kojih je potrebna primjena s oprezom ovisno o farmakogenetičkom profilu. Objectives: The aim of this study was to critically review the literature data related to the influence of genetic variants on the effect and adverse reactions of direct oral anticoagulants drugs. Material and methods: For research and writing, from the available databases, Medline and Pubmed databases were searched by keywords: direct oral anticoagulants (DOAC), dabigatran, rivaroxaban, apixaban, edoxaban, pharmacogenetics, gene polymorphisms CES1, CYP3A4, P-glycoprotein MDR1 / ABCB1, ABCB2. The selection of scientific articles in the search included all available articles in the field of pharmacogenetics, pharmacogenomics of DOAC in the last 10 years, including original scientific articles and review papers that meet the topics and objectives of the research set in the paper. This paper also included cases from routine testing within the treatment of patients at the Clinical Hospital Center Zagreb in the Department of Pharmacogenomics and Individualization of Therapy, in compliance with all ethical principles. Results: A review of the literature reveals that DOAKs interact with certain groups of drugs depending on their metabolic pathway. Likewise, polymorphisms of transport proteins and enzymes affect the occurrence of major adverse events in the form of bleeding. Conclusion: Although new oral anticoagulants are safe drugs in most patients, there is still a certain percentage of patients who require caution depending on the pharmacogenetic profile.

The use of antidepressants has been steadily increasing. Even though the amount of evidence on the usefulness of personalized drug dosing in depression treatment is growing, there is still resistance and skepticism among physicians and regulators regarding the implementation of CYP450 genotyping and therapeutic drug monitoring in psychiatric clinical practice. The aim of this study was to quantify the opinions of psychiatrists and patients from three large psychiatric clinics in Belgrade, Serbia, and to examine what requirements need to be met to make changes in clinical guidelines or recommendations. All participants completed an anonymous questionnaire that was developed at the Faculty of Pharmacy, University of Belgrade. Fourteen practicing psychiatrists and 30 patients currently treated for depression completed the questionnaire. Distributions of opinion scores were compared between the psychiatrists and patients upon the visual inspection of the violin plots. Our results show that psychiatrists predominantly have a positive opinion on personalized dosing in psychiatry and that patients are most likely to comply with new approaches in depression pharmacotherapy. However, due to the long time needed for regulatory change, it is very unlikely that personalized dosing would be rapidly implemented in clinical practice, even if adequate evidence was to emerge. Upotreba antidepresiva je u stalnom porastu. Iako raste količina dokaza o korisnosti personalizovanog doziranja lekova u lečenju depresije, još uvek postoji veliki otpor i skepticizam među lekarima i regulatorima u pogledu primene CYP450 genotipizacije i terapijskog praćenja lekova u psihijatrijskoj kliničkoj praksi. Cilj ove studije je bio da se kvantifikuju mišljenja psihijatara i pacijenata sa tri velike psihijatrijske klinike u Beogradu, u Srbiji, i da se ispita koji zahtevi treba da budu ispunjeni da bi se izvršile promene u kliničkim smernicama ili preporukama za doziranje antidepresiva. Svi učesnici su popunili anonimni upitnik koji je izrađen na Farmaceutskom fakultetu Univerziteta u Beogradu. Upitnik je popunilo 44 učesnika, od kojih 14 psihijatara i 30 pacijenata koji se trenutno leče od depresije. Dodatno je kontaktiran i jedan stručnjak za farmakologiju. Distribucija ocena mišljenja je poređena između psihijatara i pacijenata nakon vizuelnog pregleda violina dijagrama. Naši rezultati pokazuju da psihijatri uglavnom imaju pozitivno mišljenje o personalizovanom doziranju u psihijatriji i da bi se pacijenti većinski pridržavali novih pristupa u farmakoterapiji depresije. Međutim, malo je verovatno da bi regulatorna tela u Srbiji brzo ažurirala svoje smernice, čak i ako bi se pojavili adekvatni dokazi.

Uvod: Precizna medicina obuhvaća metode liječenja usmjerene prema potrebama individualnog bolesnika na osnovi genskih karakteristika, biomarkera, fenotipa ili psihosocijalnih karakteristika uz prilagođavanje medicinskih postupaka individualnim karakteristikama svakog bolesnika. Diskusija: Za uspješnost i učinkovitost precizne medicine postoji potreba za klasifikacijom bolesnika na osnovi podložnosti određenoj bolesti ili na osnovi odgovora na liječenje, čime se omogućava usmjeravanje preventivnih ili terapijskih intervencija za one koji će imati najveću korist. U neuropedijatriji precizna medicina zauzela je najčvršće mjesto u epilepsijama, a primjena se nalazi i u neuromišićnim i drugim bolestima. Sudjelujući u studijama i prikupljajući multidimenzionalne podatke o našim bolesnicima pomičemo granice precizne medicine kako bi sljedeće generacije ovaj novi koncept mogle još bolje definirati i upotrijebiti za veći broj bolesnika. Zaključak: Pred nama je još uvijek dug put do integracije precizne medicine u kliničku praksu. Visoka cijena liječenja, precizne informacije o riziku i koristi liječenja kao i konsenzus o standardizaciji evaluacije učinkovitosti pojedinog dijagnostičkog postupka ili metode liječenja još stoje kao neostvareni ciljevi precizne medicine prema kojima moramo težiti., Introduction: Precision medicine is defined as methods of treatment targeted towards needs of individual patient based on genetic characteristics, biomarkers, phenotype, or psychosocial characteristics with modifications of medical procedures to the individual needs of each patient. Discussion: To achieve success and efficacy of precision medicine there is a need for classifying patients based on their affinity to disease or based on their response to therapeutical interventions what enables focusing of preventive or therapeutical interventions to those who will benefit the most. In child neurology precision medicine is strongest in epilepsies, but the relevance is seen in neuromuscular and other diseases. By participating in clinical studies and collecting multidimensional dana on our patients we move the limits of precision medicine to allow future generation to define this concept even better and to use it for even more patients. Conclusion: We still have a long way to full integration of precision medicine to clinical practice. High cost of treatment, precise information on risks and benefits of treatment, as well as consensus on standardization of efficacy evaluation for particular diagnostic procedure or treatment method still stand as goals of precision medicine that we need to strive to.

The CYP2D6 gene encodes the homonymous enzyme responsible for the metabolism of about 25% of clinically prescribed drugs, although it accounts for only 2% of all cytochromes in the human liver. The Roma are an example of a founder population where centuries of isolation and migrations have left their mark on the gene pool. Results of this study showed the influence of demographic history on single nucleotide polymorphisms in three socioculturally different studied Roma populations. Their South Asian origin is seen in the frequencies of polymorphic variants, as well as the increased frequency of star alleles *10 and *41. Phenotypically, normal metabolizers are the most common among Roma (51.6-65.1%), while slow metabolizers are the least common (0-7.4%). The similarity of the Roma population to European and Asian populations is evident from the LD pattern of the CYP2D6 gene region. The three Roma groups differ significantly (p

Cilj istraživanja: Cilj ovog rada jest sistematično i pregledno prikazati farmakogenetiku 5-fluorouracila (5-FU-a) i polimorfizme gena za dihidropirimidin-dehidrogenazu (DPYD) koji utječu na učinkovitost i sigurnost terapije 5-FU-om. Time bi se zdravstvenim djelatnicima olakšala odluka o odbacivanju ili odabiru i individualizaciji terapije 5-FU-om prema određenom genotipu onkološkog pacijenta kojem je potrebno liječenje 5-FU-om, a sve u svrhu sigurnog liječenja i prevencije teških nuspojava i smrti. Materijali i metode: Pretražena je znanstvena literatura objavljena u bazama podataka Medline i PubMed u posljednjih 10 godina. Također su pretražene publikacije stručnih udruga i institucija, baze lijekova te ostali znanstveni izvori. Komentirane su terapijske smjernice za primjenu i individualizaciju terapije 5-FU-om (polimorfizmi gena DPYD-a c.1905+1G>A, c.1679T>G, c.2846A>T i c.1236G>A). Opisana je i moguća važnost drugih polimorfizama DPYD-a (c.496A>G, c.85T>C i c.2194G>A) te su navedene i međuetničke i međurasne razlike u učestalosti nekih polimorfizama DPYD-a. Izneseni su i podaci o mogućnostima individualizacije terapije 5-FU-om u Hrvatskoj, tj. informacije o laboratorijima koji provode genotipizaciju DPYD-a. Rezultati: Aktivnost enzima dihidropirimidin-dehidrogenaze (DPD) ograničavajući je faktor brzine metabolizma 5-FU-a i podliježe velikoj varijabilnosti stoga su bolesnici s nedostatkom DPD-a pod povećanim rizikom od toksičnosti povezane s fluoropirimidinima. Smjernice za genotipizaciju DPYD-a i doziranje fluoropirimidina izdane od strane CPIC-a (Clinical Pharmacogenetics Implementiation Consortium) uključuju 4 varijante gena DPYD za koje je dokazano da smanjuju aktivnost DPD-a (c.1905+1G>A, c.1679T>G, c.2846A>T i c.1236G>A). Proučavani su i drugi polimorfizmi (c.496A>G, c.85T>C i c.2194G>A) te većina rezultata govori u prilog smanjene aktivnosti enzima DPD-a uslijed njihove prisutnosti. U talijanskoj randomiziranoj studiji Three or six colon adjuvant (TOSCA) ozbiljne i teške nuspojave zabilježene su u 38,2 % ispitanika (nositelji mutacija c.2194G˃A, c.1905+1G˃A i c.496A˃G). Kliničko ispitivanje Pan-European Trials in an Alimentary Tract Cancer (PETACC-8) također potvrđuje gore navedeno jer je u istom utvrđeno da su se ozbiljne nuspojave javljale u 85,7 % nositelja mutacije c.2846A˃T i 60,8 % nositelja mutacije c.2194G˃A. Božina i suradnici su zabilježili ozbiljne nuspojave u čak 56,3 % ispitanika (nositelji varijanti c.496A>G ili c.2194G>A) dok mutacija c.85T>C nije bila povezana s razvojem ozbiljnih nuspojava. U radu Henricks i suradnika pokazano je da je predterapijsko testiranje isplativo ili barem ne predstavlja dodatni trošak za zdravstveni sustav. Zaključak: Nositelji inaktivirajućih alela DPYD-a imaju značajno veći rizik ozbiljnih nuspojava. Zbog toga su izdane preporuke za obavljanje genetičkog testiranja DPYD-a ili mjerenja aktivnosti DPD-a prije primjene lijeka. Time se olakšava odluka o odabiru 5-FU-a i doze prema pacijentovom genetičkom profilu te se smanjuju troškovi zdravstvene zaštite jer se poboljšava liječenje i smanjuju rizici koji, osim što predstavljaju teško stanje i patnju za pacijenta, za zdravstveni sustav predstavljaju i trošak u zbrinjavanju nuspojava liječenja. Objectives: This thesis aim is to systematically and clearly present the pharmacogenetics of 5-fluorouracil (5-FU) and DPYD gene polymorphisms that affects the efficacy and safety of 5-FU therapy. Healthcare professionals would find it easier to decide whether to reject or select and individualize 5-FU therapy according to the specific genotype of an oncology patient in need of 5-FU treatment, thus providing the safe treatment and prevention of severe side effects and death. Materials and methods: The scientific literature in databases Medline and PubMed in the last 10 years has been searched. Publications of professional associations and institutions, drug databases and other scientific sources also were searched. Therapeutic guidelines for the application and individualization of 5-FU therapy are commented (the most important polymorphisms of the DPYD gene c.1905+1G>A, c.1679T>G, c.2846A>T and c.1236G>A). The possible importance of other DPYD polymorphisms (c.496A>G, c.85T>C and c.2194G>A) is also described, and interethnic and interracial differences in the frequency of some DPYD polymorphisms are listed. Information on laboratories that perform DPYD genotyping and the possibilities of individualization of 5-FU therapy in Croatia are also presented. Results: DPD activity is a limiting factor in the rate of 5-FU metabolism and is subject to high variability, therefore patients with DPD deficiency are at increased risk of toxicity related to fluoropyrimidines. Guidelines for DPYD genotyping and fluoropyrimidine dosing were published by CPIC (Clinical Pharmacogenetics Implementation Consortium), which include 4 variants that have been shown to reduce DPD activity (c.1905+1G>A, c.1679T>G, c.2846A>T and c.1236G A). Other polymorphisms (c.496A>G, c.85T>C and c.2194G>A) have been studied in various studies and most of the results speak in favor of reduced activity of DPD enzymes due to their presence. In the Italian randomized study Three or six colon adjuvant (TOSCA), serious and severe side effects were reported in 38.2 % of subjects (carriers of mutations c.2194G˃A, c.1905+1G˃A and c.496A˃G). Clinical trial Pan-European Trials in an Alimentary Tract Cancer (PETACC-8) also confirms the above mentioned as it was found that serious side effects occurred in 85.7 % of carriers of mutation c.2846A˃T and 60.8 % of carriers of mutation c.2194G˃А. Božina and co-workers reported serious side effects in 56.3 % of subjects (carriers of c.496A>G or c.2194G>A) while c.85T>C mutation was not associated with the development of serious side effects. The work of Henricks and co-workers has shown that pre-therapy testing is cost-effective or at least does not represent an additional cost to the health care system. Conclusion: Carriers of DPYD inactivating alleles have a significantly higher risk of serious side effects. Therefore, recommendations have been issued to perform genetic testing for DPYD or to measure DPD activity prior to drug administration. This facilitates the decision on the choice of 5-FU and dose individualization according to the patient's genetic profile and reduces health care costs because it improves treatment and reduces risks that represents suffering for the patient and cost the health system.

Concomitant treatment with drugs that inhibit drug metabolising enzymes and/or transporters, such as commonly prescribed statins and nonsteroidal anti-inflammatory drugs (NSAIDs), has been associated with prolonged drug exposure and increased risk of adverse drug reactions (ADRs) due to drug-drug interactions. The risk is further increased in patients with chronic diseases/comorbidities who are more susceptible because of their genetic setup or external factors. In that light, we present a case of a 46-year-old woman who had been experiencing acute renal and hepatic injury and myalgia over two years of concomitant treatment with diclofenac, atorvastatin, simvastatin/fenofibrate, and several other drugs, including pantoprazole and furosemide. Our pharmacogenomic findings supported the suspicion that ADRs, most notably the multi-organ toxicity experienced by our patient, may be owed to drug-drug-gene interactions and increased bioavailability of the prescribed drugs due to slower detoxification capacity and decreased hepatic and renal elimination. We also discuss the importance of CYP polymorphisms in the biotransformation of endogenous substrates such as arachidonic acid and their modulating role in pathophysiological processes. Yet even though the risks of ADRs related to the above mentioned drugs are substantially evidenced in literature, pre-emptive pharmacogenetic analysis has not yet found its way into common clinical practice.Statini i nesteroidni protuupalni lijekovi (NSAID) učestalo se propisuju, pa i kao konkomitantna terapija. Postoji značajna interindividualna razlika u osjetljivosti na njihove najčešće nuspojave. Rizični čimbenici za razvoj nuspojava tih lijekova mogu biti povezani s lijekom i pacijentom ili s vanjskim čimbenicima. Polifarmacija je česta u kroničnih bolesnika i povećava rizik od razvoja interakcija lijekova. Istodobna primjena lijekovima koji inhibiraju CYP, UGT, ABC i / ili SLC prijenosnike lijekova (ABCB1, ABCG2 i OATP1B1) povezana je s produljenjem bioraspoloživosti lijekova, što rezultira povećanim rizikom od razvoja nuspojava. S tim u vezi, predstavljamo slučaj 46-godišnje žene koja je tijekom dvije godine doživjela akutno oštećenje bubrega i jetre, kao i mialgiju, dok je uzimala diklofenak, atorvastatin, fiksnu kombinaciju simvastatina / fenofibrata istovremeno s nekoliko drugih lijekova, uključujući pantoprazol i furosemid. Analiza dobivenih farmakogenetičkih rezultata te pregled dosadašnjeg znanja u tom području upućuju na zaključke da interakcije lijek-lijekgen mogu produljiti bioraspoloživost primijenjenih lijekova. Mehanizam se argumentirano temelji na sporijoj sposobnosti detoksikacije i smanjenoj eliminaciji putem jetre i bubrega, što rezultira toksičnošću za više organa. Jednako tako, prikazuje se važnost polimorfizama CYP u biotransformaciji endogenih supstrata poput arahidonske kiseline i u njihovoj modulacijskoj ulozi u patofiziološkim procesima. Danas postoje prilično značajni znanstveni dokazi o određenim farmakogenetičkim spoznajama koji rezultiraju povećanim rizikom od razvoja nuspojava za spomenute lijekove, no unatoč tomu, farmakogenetička analiza prije uvođenja lijekova u terapiju još nije uvedena u redovitu kliničku praksu.

Maligna hipertermija (MH) farmakogenetička je bolest koja se nasljeđuje autosomno dominantno i ima nepotpunu penetrabilnost. Njezina je procijenjena učestalost 1:100 000 – 1:250 000 u općoj populaciji. Varijante sekvence gena koji su uključeni u regulaciju otpuštanja kalcija iz sarkoplazmatskog retikuluma uzrokuju nastanak ove bolesti. Trenutno je priznato 48 varijanti sekvence gena za rijanodinski RyR1 receptor koji se nalazi na 19. kromosomu i 2 za dihidropiridinski receptor (CACNA1S - engl. Calcium Voltage-Gated Channel Subunit Alpha1 S), a od spominju se još i varijante sekvence STAC3 (engl. SH3 And Cysteine Rich Domain) gena. Zbog tih varijanti sekvence dolazi do promijenjenog odgovora na hlapljive anestetike i sukcinilkolin, koji izazivaju pojačano otpuštanje kalcijevih iona iz sarkoplazmatskog retikuluma i posljedično mišićne kontrakcije koje pak dovode do hipermetaboličkog stanja. U praksi se to očituje povišenjem tjelesne temperature, spazmom mišića, razvojem acidoze, hipoksijom, hiperkapnijom, acidozom i tahikardijom. Komplikacije koje se mogu javiti jesu diseminirana intravaskularna koagulopatija, akutno bubrežno zatajenje i multiorgansko zatajenje. Klinička se dijagnoza postavlja na temelju Kriterija za kliničko stupnjevanje maligne hipertermije koji su bazirani na kliničkoj slici, dok se sama dijagnoza postojanja MH zasniva na testu kontrakture i farmakogenetičkom testiranju. Kliničko se zbrinjavanje sastoji od 4 glavne komponente – uklanjanja okidajućeg agensa, primjene dantrolena, snižavanja tjelesne temperature i zbrinjavanja komplikacija. Cilj ovog diplomskog rada je prikazati farmakogenetičku bolest – malignu hipertermiju, ukazati na njezinu genetičku pozadinu, opisati kliničku sliku i dijagnostički postupak., Malignant hyperthermia is an autosomal dominant pharmacogenetic disease with incomplete penetrance. Its prevalence is estimated to be 1:100 000 – 1:250 000 in the general population. Variants of genes involved in sarcoplasmic calcium release cause this disorder. Currently, there are 48 variants of the RyR1 gene located on the 19th chromosome, and 2 variants of CACNA1S (Calcium Voltage-Gated Channel Subunit Alpha1 S) gene that are accepted as disease-causative genes but variants of the STAC3 (SH3 And Cysteine Rich Domain) gene are also mentioned in literature. Because of these variants, there is an altered response to volatile anaesthetics and succinylcholine leading to an increased release of calcium ions from the sarcoplasmic reticulum thus causing a hypermetabolic state. Clinically, this state manifests as increase in core body temperature, muscle spasm, hypoxia, hypercapnia, acidosis, and tachycardia. The complications that can occur include disseminated intravascular coagulopathy, acute kidney failure and multiorgan failure. The clinical diagnosis is established following the Criteria for clinical grading of malignant hyperthermia proposed by Larach et al. (1994) and Rosenberg et al. (2015). These criteria are based upon the clinical presentation. For the final diagnosis, contracture test and/or pharmacogenetic testing are needed. Treatment follows four base principles – discontinuation of triggering agent, admission of dantrolene, lowering of core body temperature and treating complications. The aim of this graduate thesis is to present a pharmacogenetic disease – malignant hyperthermia, to indicate its genetic background, describe the clinical presentation and diagnostic procedure.

Direktni oralni antikoagulansi (DOAK) posljednjih su godina pokazali rastući trend propisivanja zbog povoljne farmakokinetike i farmakodinamike bez potrebe za rutinskim nadzorom koagulacije. Svoj antikoagulantni učinak ostvaruju izravnom inhibicijom trombina (dabigatran) ili izravnom inhibicijom aktiviranog čimbenika X (rivaroksaban, apiksaban i edoksaban). Iako DOAK-i stupaju u manje interakcija s drugim lijekovima u usporedbi s varfarinom, kombinacija DOAK-a i mnogih lijekova zahtijeva oprez te u nekim slučajevima i klinički nadzor. Nedavne studije dokumentirale su interindividualnu varijabilnost u razinama DOAK-a u plazmi i odgovoru pacijenta na lijek. Iako klinički i biokemijski čimbenici mogu dovesti do interindividualnih varijabilnosti prisustvo genskih varijanti ili interakcije lijekova mogu doprinijeti tim razlikama. Potrebno je razumjeti ulogu farmakogenomike prvenstveno polimorfizam gena metaboličkih enzima i prijenosnika lijekova u interindividualnoj varijabilnosti četiri najčešće propisivana DOAK-a. Cilj istraživanja: Pregledno prikazati kako farmakogenetička predispozicija, prvenstveno polimorfizmi gena CYP3A4/5 i CES1, koji kodiraju metaboličke enzime, te ABCB1 i ABCG2, koji kodiraju transportne proteine, uz interakcije lijekova u politerapiji mogu doprinijeti interindividualnoj varijabilnost razina DOAK-a u plazmi, te učinkovitosti i sigurnosti njihove primjene. Materijali i metode: Prilikom izrade ovog rada provedena je opsežna pretraga nedavno objavljenih izvornih i preglednih znanstvenih radova, kliničkih ispitivanja, in vitro studija, terapijskih smjernica i publikacija stručnih društava. Naglasak je na polimorfizmima farmakogena bitnih za farmakokinetiku DOAK-a: gena CYP3A4/5 i CES1, za enzime uključene u biotransformaciju, te gena ABCB1 i ABCG2, za transportere lijekova i njihovom doprinosu u interindividualnoj varijabilnosti i bioraspoloživosti DOAK-a, te rizicima razvoja neželjenih učinaka prvenstveno krvarenja. Pretražena je baza podataka PubMed, Web of Science, Cochrane, Google Schoolar koristeći ključne riječi: apiksaban, CES1, CYP3A4, CYP3A5, dabigatran, direktni oralni antikoagulansi, edoksaban, farmakogenetika, farmakogenomika, genske varijante, interakcije gen-lijek, interakcije lijek-lijek, 4 krvarenje, novi oralni antikoagulansi, polimorfizam gena transportera ABCB1, ABCG2, rivaroksaban, SNP, tromboembolijski događaji u razdoblju od zadnjih 10-ak godina. Prikazani su interesantni slučajevi pacijenata iz kliničke prakse koji su zbog farmakogenetičke predispozicije i interakcije lijekova razvili nuspojave DOAK-a u vidu krvarenja. Raspravljene su prisutne dileme, te predočeno trenutno stanje u Hrvatskoj uspoređeno sa situacijom u Europi i drugdje u svijetu. Rezultati: Nekoliko varijanti gena CES1 i ABCB1 se smatra potencijalno odgovornim za nastanak interindividualnih varijabilnosti DOAK-a. Utvrđeno je da su varijante gena CES1 rs2244613 i rs8192935 povezane s nižim trough koncentracijama dabigatrana i nižim rizikom od krvarenja. S druge strane varijanta gena ABCB1 rs1045642 povezuje s povećanim vršnim koncentracijama dabigatrana i rivaroksabana, te povećanom učestalošću krvarenja. Farmakogenetička analiza varijanti gena ABCB1 rs2032582 (C.2677G> T) i rs104562 (C3435C> T) mogla bi biti opravdana i od koristi kod pacijenata na terapiji rivaroksabanom. Da bi se spriječili neželjeni učinci tijekom terapije apiksabanom kod nositelja nefunkcionalnih alela gena CYP3A5 potrebano je pažljivo odabrati dozu i pratiti nuspojave. Postoji veliki rizik od razvoja neželjenih učinaka lijeka kad se edoksaban kombinira s lijekovima koji inhibiraju CYP izoenzime u homozigotnih nositelja nefunkcionalnih alela za gen CYP3A5. Zaključak: Polimorfizam gena zajedno s istovremenom primjenom inhibitora/induktora transportnih proteina ili enzima odgovornih za metabolizam lijeka može povećati rizik od nastanka štetnih događaja vezanih uz promjenu DOAK-a. Due to good pharmacokinetics and pharmacodynamics without the requirement for routine coagulation monitoring, direct oral anticoagulants (DOAK) have seen an increase in prescribing in recent years. DOAC achieves its anticoagulant effect by direct inhibition of thrombin (dabigatran) or direct inhibition of activated factor X (rivaroxaban, apixaban and edoxaban). Although DOACs interact less with other drugs compared to warfarin, the combination of DOAC and many drugs requires caution and clinical supervision in some cases. Recent studies have documented interindividual variability in DOAC plasma levels and patient response to the drug. Although clinical and biochemical factors may lead to interindividual variability, the presence of genetic variants or drug interactions may contribute to these differences. The role of pharmacogenomics, namely polymorphism of metabolic enzyme genes and drug transporters, in the interindividual variability of the four most often prescribed DOACs, must be understood. Objectives: Demonstrate how pharmacogenetic predisposition, primarily polymorphisms of CYP3A4 / 5 metabolic enzyme genes, and CES1 and ABCB1 and ABCG2 transport proteins with drug interactions in polytherapy, may contribute to interindividual variability in DOAC plasma levels, and their efficiency and safety. Materials and methods: During the preparation of this paper, an extensive search of recently published original and reviewed scientific papers, clinical trials, in vitro studies, therapeutic guidelines and publications of professional societies was conducted. The emphasis is on pharmacogen polymorphisms that are important for DOAC pharmacokinetics: CYP3A4 / 5 and CES1 genes, for enzymes involved in biotransformation, and ABCB1 and ABCG2 genes, for drug transporters and their contribution to interindividual variability and bioavailability of DOACs, effects primarily of bleeding. The database PubMed, Web of Science, Cochrane, Google Schoolar were searched using keywords: apixaban, CES1, CYP3A4, CYP3A5, dabigatran, direct oral anticoagulants, edoxaban, pharmacogenetics, pharmacogenomics, gene variants, drug-drug interactions, gene-drug interactions, bleeding, new oral anticoagulants, polymorphism of transporter genes ABCB1, ABCG2, rivaroxaban, SNP, thromboembolic events in the period of the last 10 years. Interesting cases of patients from clinical practice who have developed DOAC side effects in the form of bleeding due to pharmacogenetic predisposition and drug interactions are presented. The present dilemmas were discussed, and the current situation in Croatia was compared to the situation in Europe and elsewhere in the world. Results: Several variants of the CES1 and ABCB1 genes are thought to be potentially responsible for the occurrence of interindividual variability in DOAC. Variants of the CES1 rs2244613 and rs8192935 genes were found to be associated with lower trough out dabigatran concentrations and a lower risk of bleeding. On the other hand, the ABCB1 gene variant rs1045642 is associated with increased peak concentrations of dabigatran and rivaroxaban, and increased bleeding frequency. Pharmacogenetic analysis of the ABCB1 gene variants rs2032582 (C.2677G>T) and rs104562 (C3435C>T) could be justified and useful in patients on rivaroxaban therapy. To prevent side effects during apixaban therapy in carriers of non-functional alleles of the CYP3A5 gene, the dose should be carefully selected and adverse reactions monitored. There is a high risk of developing adverse drug reactions when edoxaban is combined with drugs that inhibit CYP isoenzymes in homozygous carriers of non-functional alleles for the CYP3A5 gene. Conclusion: Gene polymorphism in combination with the concomitant use of inhibitors / inducers of transport proteins or enzymes responsible for drug metabolism may increase the risk of adverse events associated with alterations in DOACs.

Background The most common psychiatric complications due to dopaminergic treatment in Parkinson’s disease are visual hallucinations and impulse control disorders. Their development depends on clinical and genetic factors. Methods We evaluated the simultaneous effect of 16 clinical and 34 genetic variables on the occurrence of visual hallucinations and impulse control disorders. Altogether, 214 Parkinson’s disease patients were enrolled. Their demographic, clinical, and genotype data were obtained. Clinical and clinical-pharmacogenetic models were built by The Least Absolute Shrinkage and Selection Operator penalized logistic regression. The predictive capacity was evaluated with the cross-validated area under the receiver operating characteristic curve (AUC). Results The clinical-pharmacogenetic index for prediction of visual hallucinations encompassed age at diagnosis (OR = 0.99), rapid eye movement (REM) sleep behavior disorder (OR = 2.27), depression (OR = 1.0002), IL6 rs1800795 (OR = 0.99), GPX1 s1050450 (OR = 1.07), COMT rs165815 (OR = 0.69), MAOB rs1799836 (OR = 0.97), DRD3 rs6280 (OR = 1.32), and BIRC5 rs8073069 (OR = 0.94). The clinical-pharmacogenetic index for prediction of impulse control disorders encompassed age at diagnosis (OR = 0.95), depression (OR = 1.75), beta-blockers (OR = 0.99), coffee consumption (OR = 0.97), NOS1 rs2682826 (OR = 1.15), SLC6A3 rs393795 (OR = 1.27), SLC22A1 rs628031 (OR = 1.19), DRD2 rs1799732 (OR = 0.88), DRD3 rs6280 (OR = 0.88), and NRG1 rs3924999 (OR = 0.96). The cross-validated AUCs of clinical and clinical-pharmacogenetic models for visual hallucinations were 0.60 and 0.59, respectively. The AUCs of clinical and clinical-pharmacogenetic models for impulse control disorders were 0.72 and 0.71, respectively. The AUCs show that the addition of selected genetic variables to the analysis does not contribute to better prediction of visual hallucinations and impulse control disorders. Conclusions Models could be improved by a larger cohort and by addition of other types of Parkinson’s disease biomarkers to the analysis.

Uvod: Za mnoge novije kardiovaskularne (KV) lijekove broj PGx istraživanja je ograničen i nema jednoznačnih zaključaka. Cilj je istražiti ulogu farmakogena kao i višestruke interakcije lijek- lijek-gen i njihovu važnost za predviđanje nuspojava KV lijekova. Materijali i metode: Ovaj projekt je planiran kao prospektivno istraživanje „ugnježđenih slučajeva i kontrola“ u trajanju od 60 mjeseci i uključit će 1200 konsekutivno uključenih ispitanika. Primarna kohorta uključuje pacijente s novopostavljenom indikacijom za primjenu direktnih oralnih antikoagulansa (DOAK: dabigatran eteksilat, apiksaban, rivaroksaban, edoksaban) ; inhibitora agregacije trombocita (klopidogrel, prasugrel, tikagrelor), i/ili inhibitora HMG-CoA reduktaze (simvastatin, atorvastatin, rosuvastatin). Slučajevi obuhvaćaju ispitanike kojima se tijekom praćenja uoče nuspojave: krvarenja i pojava vaskularnih incidenata tj. neučinkovitost lijeka za DOAK-e i antitrombocitne lijekove, te miotoksičnost i hepatotoksičnost za statine. Kontrolnu skupinu čine oni ispitanici u kojih se tijekom trajanja istraživanja ne uoči razvoj nuspojava. Svi ispitanici su genotipizirani metodom PCR u stvarnom vremenu za relevantne varijante gena ADME: CYP2C9*2, *3, CYP2C19*2, *3, *17, CYP2D6*3, *4, *5, *6, *9, *10, *41 i xN, CYP2J2*7, CES1 (rs2244613, rs8192935), ABCB1 (c.1236C>T, c.2677G>T/A, c.3435C>T, rs4148738), ABCG2 c.421C>A, SLCO1B1 c.521T>C, a praćeni su i klinički i laboratorijski parametri. Za interakcije lijekova (DDI) primijenjen je Lexicomp® sustav. Rezultati: Do sada je regrutirano 450 pacijenata (215 žena, 235 muškaraca). Genotipitacija je provedena ovisno o terapiji ; CYP2C9 (n=211 ; 47%), CYP2C19 (n=262 ; 58%), CYP3A4 (n=335, 74%), CYP3A5 (n=299, 66%), CYP2D6 (n=101, 22%), CES1 (n=32, 7%), ABCB1 (n=282, 63%), ABCG2 (n=357, 79%), te SLCO1B1 (n=214, 48%). Uočene nuspojave su: miotoksičnost (n=84, 17%), hepatotoksičnost (n=14, 3%), krvarenje (n=36, 9%). Potencijalne interakcije lijekova otkrivene su u skupini statina (n=39/182), DOAK (n=133/135) i antiagregacijski lijekovi (n=68/76). Zaključak: Naši preliminarni podaci ukazuju na interakcije lijek-lijek-gen kao važan čimbenik rizika za kardiovaskularne nuspojave lijekova. Očekujemo da će rezultati projekta donijeti nova znanstvena saznanja o povezanosti farmakogena s učinkovitosti i sigurnosti primjene KV lijekova specifično u populaciji ispitanika s komorbiditetima i politerapijom.

Enzimi pod-porodice citokroma P450 3A (CYP3A) sudjeluju u metabolizmu oko 50% lijekova u kliničkoj primjeni. Najvažniji su enzimi CYP3A4 i CYP3A5, za koje je karakteristična interindividualna varijabilnost. Genetičke varijante mogu objasniti dio varijabilnosti aktivnosti CYP3A. Klinički najvažnije su varijante CYP3A5*3 i CYP3A4*22, manje važan je polimorfizam CYP3A4*1B. Podaci o učestalosti polimorfizama CYP3A u hrvatskoj populaciji postoje, ali nisu iz istog skupa podataka. U ovom radu su istraživane učestalosti CYP3A4*1B, CYP3A4*22 i CYP3A5*3 u istom skupu podataka u hrvatskoj populaciji. Uzorci DNA izolirani su iz uzoraka pune krvi tijekom 8 godina rutinskih farmakogenetičkih analiza u Kliničkom bolničkom centru Zagreb. U ovo istraživanje uključen je ukupno 1100 ispitanik. Genotipizacija CYP3A4*1B, CYP3A4*22 i CYP3A5*3 je provedena PCR metodom u stvarnom vremenu TaqMan®. Učestalosti varijantnih alela bile su za CYP3A4*1B=0.0698 (n=258), CYP3A4*22=0.0355 (n=1100) i CYP3A5*3=0.9645 (n=440). Analiza genotipova polimorfizama pokazala je: (i) za CYP3A4*1B 86,43% ispitanika su nositelji genotipa*1/*1, 13,18% genotipa *1/*1B, a 0,39% genotipa *1B/*1B; (ii) za CYP3A4*22 93,09% su nositelji genotipa *1/*1, 6,73% genotipa *1/*22, a 0,18% genotipa *22/*22; (iii) za CYP3A5*3 83,18% ispitanika su nositelji genotipa *3/*3, 16,14% genotipa *1/*3, a 0,68%, a genotipa *1/*1. U ovom radu su učestalosti svih ispitivanih polimorfizama su bile nešto veće od prethodnih studija provedenih u hrvatskoj populaciji, jer se radi o pacijentima koji su genotipizirani u kliničkom okružju zbog nuspojava i/ili neučinkovitosti lijekova supstrata CYP3A. Učestalost alela i genotipova varijanti CYP3A4*1B, CYP3A4*22 i CYP3A5*3 u hrvatskoj populaciji u skladu je s ostalim europskim populacijama. Cytochrome P450 3A (CYP3A) subfamily enzymes are involved in the metabolism of about 50% of drugs in clinical use. The most important are CYP3A4 and CYP3A5 enzymes, which are characterised by interindividual variability. Genetic variants can explain part of the variability of CYP3A activity. The clinically most important are variants CYP3A5*3 and CYP3A4*22, while the CYP3A4*1B is less important. Data on the frequency of CYP3A polymorphisms in the Croatian population exist, but they are not from the same dataset. In this study, the frequencies of CYP3A4*1B, CYP3A4*22 and CYP3A5*3 were investigated in the same data set in the Croatian population. DNA samples were extracted from whole blood samples over eight years of routine pharmacogenetic testing at the University Hospital Centre Zagreb. A total of 1100 subjects were included in this study. Genotyping of CYP3A4*1B, CYP3A4*22 and CYP3A5*3 was performed by the TaqMan® real-time PCR method. CYP3A allele frequencies were CYP3A4*1B=0.0698 (n=258), CYP3A4*22=0.0355 (n=1100) and CYP3A5*3=0.9645 (n=440). The analysis of genotypes showed: (i) for CYP3A4*1B, 86.43% of subjects were carriers of genotype *1/*1, 13.18% of genotype *1/*1B, and 0.39% of genotype *1B/*1B; (ii) for CYP3A4*22, 93.09% are carriers of the *1/*1 genotype, 6.73% of the *1/*22 genotype, and 0.18% of the *22/*22 genotype; (iii) for CYP3A5*3, 83.18% of respondents are carriers of the *3/*3 genotype, 16.14% of the *1/*3 genotype, and 0.68% of the *1/*1 genotype. In this study, the frequencies of all investigated polymorphisms were slightly higher than in previous studies conducted on the Croatian population. The frequency of the CYP3A4*1B, CYP3A4*22 and CYP3A5*3 variant alleles and genotypes in the Croatian population is in accordance with the other European populations.

This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the authors do not have intention to replace the role of a physician in process of prescribing the drugs. Dieses Buch enthält Informationen aus authentischen und vertrauten Quellen. Es erforderte sehr große Anstrengungen um verlässliche Daten und Informationen zu veröffentlichen , aber die Autoren haben nicht die Absicht, die Rolle eines Arztes im Verfahren der Verschreibung der Medikamente zu ersetzen. Ova knjiga sadrži informacije dobivene od autentičnih i pouzdanih izvora. Učinjeni su veliki napori kako bi se objavili pouzdani podaci i informacije, no autori nemaju namjeru zamijeniti ulogu liječnika u procesu propisivanja lijekova.

Background and Objectives: Methotrexate is widely prescribed for the treatment of moderate-to-severe psoriasis. As drug survival encompasses efficacy, safety, and treatment satisfaction, such studies provide insights into successful drug treatments in the real-life scenario. The objective was to define methotrexate drug survival and reasons for discontinuation, along with factors associated with drug survival, in a cohort of adult patients with moderate-to-severe plaque psoriasis. Materials and Methods: Data on methotrexate treatment were extracted from our institutional registry. Drug survival was estimated by Kaplan–Meier analysis, and predictors of drug survival were analyzed by Cox proportional hazards regression. Results: We included 133 patients treated with methotrexate. Due to significant effects of the year of treatment initiation, drug survival analysis was performed for 117 patients who started methotrexate in 2010 or later. Median methotrexate drug survival was 11.0 months. Overall, 89% of patients discontinued treatment, with over half of these (51%) due to lack of efficacy. Significantly longer drug survival was seen for patients who discontinued treatment due to lack of efficacy versus drug safety (p = 0.049), when stratified by sex, this remained significant only for women (p = 0.002). The patient ABCC2 rs717620 genotype was significantly associated with drug survival in both univariate log-rank and multivariate Cox regression analyses, with variant T allele associated with longer drug survival (hazard ratio, 0.606, 95% confidence interval, 0.380–0.967, p = 0.036). Conclusions: We have identified the novel association of patient ABCC2 rs717620 genotype with methotrexate drug survival. This pharmacogenetic marker might thus help in the management of psoriasis patients in daily practice.

Antidepresivi su jedna od najčešće propisivanih skupina lijekova. Koriste se za liječenje depresije, anksioznosti, opsesivno-kompulzivnog poremećaja, neuropatske boli i prevenciju migrene. Incidencija depresije u svjetskoj populaciji je oko 16 %. Antidepresivi imaju izražen metabolizam prvog prolaza putem citokroma P450 (CYP), i to najviše putem CYP2D6, CYP2C19, CYP3A4, CYP2C9 i CYP1A2. U terapiji depresije najznačajniji su polimorfizmi CYP2D6 i CYP2C19 enzima jer mogu imati utjecaj na metabolizam selektivnih inhibitora ponovnog povrata serotonina i tricikličkih antidepresiva, tj na učinkovitost i sigurnost lijekova. Na temelju genetičkih informacija o polimorfizmima gena iz obitelji CYP-a može se zaključiti o mogućim fenotipovima biotransformacije/metaboliziranja lijeka. Genotipovi određuju četiri različita fenotipa. Normalni metabolizatori imaju normalnu enzimsku aktivnost, to su prvenstveno homozigotni nositelji “divljega” alela. Intermedijarni metabolizatori u usporedbi s normalnim metabolizmom imaju smanjenu enzimsku aktivnost zbog prisustva odgovarajućih varijantnih alela sa smanjenom funkcijom ili gubitkom funkcije. Spori metabolizatori imaju značajno smanjenu enzimsku aktivnost ili ona potpuno izostaje jer su homozigotni nositelji inaktivirajućih alela/varijanti gena. Vrlo brzi metabolizatori imaju enzimsku aktivost koja je veća od normalne, prosječne, zbog prisustva više kopija gena. Društva poput Kliničkog konzorcija za implementaciju farmakogenetike i Nizozemske radne grupe za farmakogenetiku izdala su smjernice za doziranje antidepresiva. Smjernice upućuju na promjenu doze i/ili lijeka u slučaju bolesnika sa sporim, a u nekim slučajevima i intermedijarnim metaboličkim fenotipom za CYP2C19 i/ili CYP2D6. Prilagodbom doze prema genotipu smanjuje se učestalost nuspojava i povećava učinak terapije. Farmakogenetički testovi trebaju biti razmotreni uz druge kliničke i biokemijske čimbenike s posebnim naglaskom na interakcije lijekova i druge komorbiditete. Antidepressants are one of the most commonly prescribed groups of drugs. They are used to treat depression, anxiety, obsessive-compulsive disorder, neuropathic pain and for migraine prevention. The incidence of depression in the world population is about 16%. Antidepressants have a pronounced first-pass metabolism via cytochrome P450 (CYP), mostly via CYP2D6, CYP2C19, CYP3A4, CYP2C9 and CYP1A2. The most important polymorphisms in the treatment of depression are CYP2D6 and CYP2C19 enzymes polymorphisms because they can affect the metabolism of selective serotonin reuptake inhibitors and tricyclic antidepressants, i.e., drug efficacy and safety. Based on genetic information on CYP gene polymorphism, it is possible to predict phenotypes of drug biotransformation / metabolism. There are four different phenotypes. Normal metabolizers have normal enzymatic activity, they are homozygous carriers of the "wild" type of alleles. Intermediate metabolizers have reduced enzyme activity compared to normal metabolism due to the presence of alleles with reduced or lost function. Poor metabolizers have significantly reduced or absent enzyme activity because they are homozygous carriers of inactivating alleles/gene variants. Ultrarapid metabolizers have a genotype with enzymatic activities that is higher than normal due to the presence of multiple copies of the gene. Companies such as the Clinical Pharmacogenetics Implementation Consortium and the Dutch Pharmacogenetics Working Group have issued guidelines for antidepressants dosing. The guidelines suggest dose and / or drug variation in patients with a poor and in some cases intermediate metabolic phenotype for CYP2C19 and/or CYP2D6. Adjusting the doses according to genotype reduces the frequency of side effects and increases the effect of therapy. Pharmacogenetic tests should be considered in addition to other clinical and biochemical factors with special emphasis on drug interaction and other comorbidities.

CILJ ISTRAŽIVANJA Cilj je ovoga specijalističkog rada prikupiti i kritički procijeniti relevantne podatke koji se odnose na utjecaj genskih varijanti na ishode terapije 5-fluorouracilom i irinotekanom, prikazati upute i smjernice izdane od međunarodnih tijela, te prisutne dileme u liječenju. MATERIJALI I METODE Za potrebe istraživanja i pisanja rada od dostupnih baza podataka pretraživane su baze podataka Medline i PubMed prema ključnim riječima: 5-fluorouracil, dihidropirimidin-dehidrogenaza, farmakogenetika, genski polimorfizmi i irinotekan. Odabir znanstvenih članaka publiciranih u posljednjem desetljeću obuhvaća važnije članke iz područja farmakogenetike, farmakogenomike i farmakoterapije, starije i novije objave, originalne članke kao i preglede koji zadovoljavaju tematiku i ciljeve istraživanja postavljene u radu. U radu su također prikazani i podatci o implementaciji testiranja DPYD i UGT1A1 u Hrvatskoj dobiveni u okviru doktorske disertacije dr.sc. Ivana Bilića 'Uloga polimorfizama gena dihidropirimidin-dehidrogenaze i UDP-glukuronil-transferaze u toksičnosti kemoterapije fluoropirimidinima i irinotekanom'. U tu svrhu prikazan je pregled rutinskih analiza pacijenata liječenih 5-fluorouracilom i irinotekanom tijekom tri godine (2013.-2016.) u Kliničkom zavodu za laboratorijsku dijagnostiku u Kliničkom bolničkom centru Zagreb. RASPRAVA Bolesnici s toksičnim nuspojavama na fluoropirimidine i irinotekan češće su nositelji polimorfizama gena za dihidropirimidin-dehidrogenazu, između ostalih to su DPYD*2A (c.1905+1G>A ili IVS 14+1 G>A), DPYD 496A>G (c.496A>G), te polimorfizma UGT1A1 (UGT1A1*28), u odnosu na pacijente koji nisu iskusili nuspojave. Na temelju farmakogenetičkih analiza može se u značajnoj mjeri predvidjeti razvoj nuspojava, individualizirati, tj. prilagoditi doza lijeka i time minimalizirati rizik od nastanka štetnih učinaka. ZAKLJUČAK Iako postoje jasni dokazi o vrijednosti farmakogenetičkih testiranja, njihova implementacija u svakodnevnu kliničku praksu zaostaje za tim spoznajama. Poznavanje genskih polimorfizama ne može apsolutno predvidjeti sve neočekivane reakcije pacijenta ali može značajno doprinijeti individualizaciji terapije te minimalizaciji rizika. OBJECTIVES The purpose of this specialist thesis is to collect and critically evaluate relevant data related to the influence of 5-fluorouracil and irinotecan gene variants on the outcome of therapy, to present current guidelines issued by relevant international bodies, and dilemmas in the treatment. MATERIALS AND METHODS For research and writing purposes, Medline and PubMed databases were searched for by following keywords: 5-fluorouracil, dihydropyrimidine-dehydrogenase, pharmacogenetics, gene polymorphisms and irinotecan. The selection of scientific articles published in the last decade includes the most important articles in the field of of pharmacogenetics, pharmacogenomics and pharmacotherapy, older and newer releases, original articles and reviews that meet the topic and goals of the research set in this thesis. This paper presents the latest data on the implementation of DPYD and UGT1A1 testing in Croatia obtained within the doctoral dissertation of Ivan Bilić 'The role of dihydropyrimidinedehydrogenase and UDP-glucuronyl-transferase polymorphisms in fluoropyrimidine and irinotecan toxicity'. For this purpose, the routine analyses of patients treated with 5-fluorouracil and irinotecan during the three years period (2013.-2016.), at the Clinical Institute for Laboratory Diagnosis at Zagreb Clinical Hospital Center have been presented. DISCUSSION Patients with toxic side effects of fluoropyrimidines and irinotecan are more frequent carriers of dihydropyrimidine-dehydrogenase genomic polymorphisms, among others DPYD*2A (1905 + 1G> A or IVS 14+1G> A), DPYD 496A> G (c.496A> G) and UGT1A1 polymorphism (UGT1A1*28), compared to patients who do not experience side effects. Based on pharmacogenetic analysis, it is possible to significantly anticipate the development of side effects, to individualize, i.e. to adjust the dose of the drug and minimize the risk of side effects. CONCLUSION Although there is a clear evidence of pharmacogenetic testing values, the implementation in everyday clinical practice is lagging behind these findings. Knowledge of gene polymorphisms cannot predict all unexpected responses of the patient, but can significantly contribute to the individualization of the therapy and minimizing the risk.

Objectives: Methotrexate (MTX) is the first line treatment for rheumatoid arthritis (RA), but nevertheless 30% of patients experience MTX inefficacy. Our aim was to develop a clinical pharmacogenetic model to predict which RA patients will not respond to MTX monotherapy. We also assessed whether this model can be generalized to other populations by validating it on a group of Serbian RA patients. Methods: In 110 RA Slovenian patients, data on clinical factors and 34 polymorphisms in MTX pathway were analyzed by Least Absolute Shrinkage and Selection Operator (LASSO) penalized regression to select variables associated with the disease activity as measured by Disease Activity Score (DAS28) score after 6 months of MTX monotherapy. A clinical pharmacogenetic index was constructed from penalized regression coefficients with absolute value above 0.05. This index was cross-validated and also independently validated on 133 Serbian RA patients. Results: A clinical pharmacogenetic index for prediction of DAS28 after 6 months of MTX monotherapy in Slovenian RA patients consisted of DAS28 score at diagnosis, presence of erosions, MTX dose, Solute Carrier Family 19 Member 1 (SLC19A1) rs1051266, Solute Carrier Organic Anion Transporter Family Member 1B1 (SLCO1B1) rs2306283, Thymidylate Synthase (TYMS), and Adenosine Monophosphate Deaminase 1 (AMPD1) rs17602729. It correctly classified 69% of Slovenian patients as responders or nonresponders and explained 30% of variability in DAS28 after 6 months of MTX monotherapy. Testing for validity in another population showed that it classified correctly only 22.5% of Serbian RA patients. Conclusions: We developed a clinical pharmacogenetic model for DAS28 after 6 months of MTX monotherapy in Slovenian RA patients by combining clinical and genetic variables. The clinical pharmacogenetic index developed for Slovenian patients did not perform well on Serbian patients, presumably due to the differences in patients' characteristics and clinical management between the two groups.

Farmakogenetika raziskuje genetske osnove, ki vplivajo na različne odzive posameznikov na zdravljenje. Cilj farmakogenetike je izboljšati učinkovitost in zmanjšati toksičnost terapije pri določenem posamezniku in na ta način omogočiti individualizirano zdravljenje. Tiopurinske učinkovine se uporabljajo pri zdravljenju hematoloških malignosti in avtoimunskih bolezni ter imajo nizek terapevtski indeks, zato se pogosto pojavijo življenjsko nevarni stranski učinki. Za svoje delovanje tiopurini potrebujejo metabolno aktivacijo, količina citotoksičnih in neaktivnih metabolitov pa je odvisna od aktivnosti polimorfnega encima tiopurin-S-metiltransferaze (TPMT). Na podlagi posameznikovega genotipa TPMT lahko prilagajamo odmerek tiopurinskih učinkovin in na ta način preprečimo pojav stranskih učinkov ter izboljšamo potek zdravljenja. V okviru doktorske disertacije smo raziskali povezanost genetskih polimorfizmov in encimske aktivnosti TPMT v slovenski populaciji. Ugotovili smo, da se genotipske frekvence najpogostejših polimorfizmov TPMT*3A (4,1%), TPMT*3C (0,5%) in TPMT*3B (0,3%) ujemajo z vrednostmi pri drugih populacijah Kavkazijcev. Heterozigotni posamezniki z enim mutiranih alelom so imeli nižjo aktivnost TPMT kot posamezniki z divjim tipom alelov. S statistično analizo smo določili mejo med skupinama posameznikov s srednjo in visoko aktivnostjo (9.82 pmol/107 RBC h-1) ter ugotovili, da na podlagi genotipa pravilno napovemo encimsko aktivnost TPMT pri 91,6 % posameznikov. Na ta način smo zasnovali farmakogenetske smernice in vzpostavili analizne metode, primerne za identifikacijo bolnikov s spremenjenim odzivom na tiopurine, pri katerih je potrebno znižanje doze. Zaradi nepopolnega ujemanja genotipa in fenotipa TPMT smo želeli ugotoviti dodatne faktorje, ki vplivajo na aktivnost TPMT in prekomerno toksičnost tiopurinov. V ta namen smo s pomočjo modelne celične linije za akutno limfoblastno levkemijo (ALL) preiskali molekularni mehanizem regulacije aktivnosti TPMT preko metilnega donorja S-adenozilmetionina (SAM). Ugotovili smo, da SAM preko stabilizacije proteinske strukture TPMT prepreči citostatični in citotoksični učinek 6-merkaptopurina (6-MP), zakasni apoptozo, sproženo s 6-MP, ter zniža koncentracijo znotrajceličnih citotoksičnih metabolitov. Potencialni vpliv SAM na toksičnost tiopurinov in pojav stranskih učinkov pri bolnikih z ALL smo ugotovili tudi v retrospektivni študiji, s katero smo dokazali visoko stopnjo povezave med pojavom hematotoksičnosti in prisotnostjo polimorfizmov, ki so povezani z nizko aktivnostjo TPMT in 5,10-metilentetrahidrofolat reduktazo (MTHFR), encimom, ki sodeluje pri biosintezi SAM. Z identifikacijo SAM kot pomembnega modulatorja aktivnosti TPMT in citotoksičnosti 6-MP, lahko pričakujemo upoštevanje novih genetskih in drugih kazalcev pri optimizaciji zdravljenja s tiopurini. V nadaljevanju smo vzpostavili modelne humane celične linije HEK293, HepG2 in Jurkat s stabilnim povečanim izražanjem TPMT za proučevanje endogene funkcije encima. Kot dostavni sistem za vnos plazmida z vključkom zaporedja cDNA za TPMT smo uporabili umetne virusne delce (AVP), ki so omogočili stabilno izražanje fuzijskega rekombinantnega proteina EGFP-TPMT in povečano aktivnost TPMT. Dalje smo ugotovili, da v celicah HEK293 in HepG2 s povečanim izražanjem TPMT poteka hitrejša presnova znotrajceličnega SAM, količina znotrajceličnega S-adenozilhomocisteina (SAH) pa je znižana, medtem ko metilacijski potencial ni spremenjen. Vpliva povečane ekspresije TPMT na celokupno metilacijo DNA v odsotnosti inhibicije DNA-metiltransferaz nismo ugotovili, medtem ko smo v celicah HepG2 odkrili značilno znižane vrednosti reducirane oblike glutationa. Dosedanje raziskave kažejo potencialno endogeno vlogo TPMT pri procesih, ki vplivajo na presnovo SAM, transmetilacijo in oksidativni status celice. Aktivnost TPMT je eden glavnih faktorjev pri presnovi tiopurinskih učinkovin, saj vpliva na učinkovitost zdravljenja in pojav neželenih učinkov. Poleg genetskih polimorfizmov na aktivnost TPMT vpliva tudi količina endogenega metilnega donorja SAM, katerega količina ima potencialen vpliv na pojav prekomerne toksičnosti in odziv posameznikov na tiopurinske učinkovine. Nadaljnje študije bodo razjasnile potencialno endogeno vlogo TPMT pri znotrajcelični presnovi, kar je pomembno za identifikacijo različnih fenotipov, ki nastanejo kot posledica različnih vrednosti aktivnosti encima. Pharmacogenetics studies the genetic basis of inter-individual differences in drug response. The goal of pharmacogenetic testing is to individualize drug treatment by identifying relevant factors which influence drug efficacy and lower the therapy-related toxicity in individual patients. Thiopurines are prodrugs used in the treatment of haematological malignancies and autoimmune diseases. Due to their narrow therapeutic index, they frequently exhibit life-threatening side-effects. They require metabolic activation, in order to achieve their cytotoxic effect. The amount of cytotoxic and inactive metabolites largely depends on the activity of thiopurine S-methyltransferase (TPMT), a highly polymorphic drug metabolizing enzyme. TPMT genotyping is the basis for dosage adjustment protocols to prevent thiopurine-related side-effects and improve treatment outcome. In presented dissertation, the correlation of TPMT genetic polymorphisms and enzyme activity in the Slovenian population was evaluated. The genotypic frequencies of the most common polymorphisms TPMT*3A (4.1 %), TPMT*3C (0.5 %) and TPMT*3B (0.3 %) were in accord with the values observed in other Caucasian populations. Heterozygous individuals with a single mutant allele exhibited lower enzyme activity than wild-type individuals. Statistic analysis was employed to determine the cut-off value (9.82 pmol/107 RBC h-1) between intermediate and high TPMT activity groups. The correlation between TPMT genotype and enzyme activity was 91.6 %. With the aid of relevant analytical methods, the pharmacogenetic basis for the identification of patients with altered response to thiopurines requiring dosage adjustment protocols was established. Due to the incomplete TPMT genotype-to-phenotype correlation observed in several studies, we examined the potential factors involved in additional regulation of TPMT activity and unfavourable thiopurine toxicity. Using a model cell line for acute lymphoblastic leukemia (ALL), we delineated the molecular mechanism of the effect of methyl donor S-adenosylmethionine (SAM) on TPMT activity. We found that the addition of exogenous SAM prevents 6-MP induced cytotoxicity, delays the onset of 6-MP triggered apoptosis and lowers the concentration of cytotoxic metabolites. The potential effect of SAM on thiopurine toxicity was confirmed in the retrospective study, where we established the correlation between hematotoxic events in ALL patients and the presence of TPMT genetic polymorphisms, as well as low-activity mutations in the MTHFR gene, coding for an important enzyme involved in the biosynthesis of SAM. By identifying SAM as an important modulator of TPMT activity and 6-MP cytotoxicity, novel rationalization of therapy may apply. Further, to delineate the endogenous function of TPMT, we generated human HEK293, HepG2 and Jurkat cell lines exhibiting stable TPMT overexpression. The gene delivery system termed artificial viral particles (AVP) was used to transfect the cells with a plasmid containing TPMT cDNA insert, enabling stable overexpression of the recombinant fusion EGFP-TPMT protein and elevated TPMT activity. In addition, we found that TPMT overexpression in HEK293 and HepG2 cells results in faster intracellular SAM turnover, while the concentration of intracellular S-adenosylhomocysteine (SAH) is decreased, maintaining the cellular methylation potential. The effect of TPMT overexpression on global DNA methylation was not observed in the absence of DNA methyltransferase inhibition, while significantly lower amounts of reduced glutathione were found in HepG2 cells with stable TPMT overexpression. These results show that TPMT might be involved in endogenous processes affecting the cellular SAM turnover, transmethylation reactions and oxidative status. TPMT activity is one of the major factors influencing thiopurine drug metabolism, drug efficacy and unwanted toxicity. In addition to TPMT genetic polymorphisms, other factors involved in the regulation of endogeous methyl donor SAM may influence TPMT activity, and consequently, thiopurine toxicity and drug response. Further studies will clarify the endogenous role of TPMT in intracellular metabolism, which is crucial for the identification of different phenotypes resulting from significant inter-individual differences in TPMT activity.

Statini i nesteroidni protuupalni lijekovi (NSAID) učestalo se propisuju, pa i kao konkomitantna terapija. Postoji značajna interindividualna razlika u osjetljivosti na njihove najčešće nuspojave. Rizični čimbenici za razvoj nuspojava tih lijekova mogu biti povezani s lijekom i pacijentom ili s vanjskim čimbenicima. Polifarmacija je česta u kroničnih bolesnika i povećava rizik od razvoja interakcija lijekova. Istodobna primjena lijekovima koji inhibiraju CYP, UGT, ABC i / ili SLC prijenosnike lijekova (ABCB1, ABCG2 i OATP1B1) povezana je s produljenjem bioraspoloživosti lijekova, što rezultira povećanim rizikom od razvoja nuspojava. S tim u vezi, predstavljamo slučaj 46-godišnje žene koja je tijekom dvije godine doživjela akutno oštećenje bubrega i jetre, kao i mialgiju, dok je uzimala diklofenak, atorvastatin, fiksnu kombinaciju simvastatina / fenofibrata istovremeno s nekoliko drugih lijekova, uključujući pantoprazol i furosemid. Analiza dobivenih farmakogenetičkih rezultata te pregled dosadašnjeg znanja u tom području upućuju na zaključke da interakcije lijek-lijekgen mogu produljiti bioraspoloživost primijenjenih lijekova. Mehanizam se argumentirano temelji na sporijoj sposobnosti detoksikacije i smanjenoj eliminaciji putem jetre i bubrega, što rezultira toksičnošću za više organa. Jednako tako, prikazuje se važnost polimorfizama CYP u biotransformaciji endogenih supstrata poput arahidonske kiseline i u njihovoj modulacijskoj ulozi u patofiziološkim procesima. Danas postoje prilično značajni znanstveni dokazi o određenim farmakogenetičkim spoznajama koji rezultiraju povećanim rizikom od razvoja nuspojava za spomenute lijekove, no unatoč tomu, farmakogenetička analiza prije uvođenja lijekova u terapiju još nije uvedena u redovitu kliničku praksu., Concomitant treatment with drugs that inhibit drug metabolising enzymes and/or transporters, such as commonly prescribed statins and nonsteroidal anti-inflammatory drugs (NSAIDs), has been associated with prolonged drug exposure and increased risk of adverse drug reactions (ADRs) due to drug-drug interactions. The risk is further increased in patients with chronic diseases/comorbidities who are more susceptible because of their genetic setup or external factors. In that light, we present a case of a 46-year-old woman who had been experiencing acute renal and hepatic injury and myalgia over two years of concomitant treatment with diclofenac, atorvastatin, simvastatin/fenofibrate, and several other drugs, including pantoprazole and furosemide. Our pharmacogenomic findings supported the suspicion that ADRs, most notably the multi-organ toxicity experienced by our patient, may be owed to drug-drug-gene interactions and increased bioavailability of the prescribed drugs due to slower detoxification capacity and decreased hepatic and renal elimination. We also discuss the importance of CYP polymorphisms in the biotransformation of endogenous substrates such as arachidonic acid and their modulating role in pathophysiological processes. Yet even though the risks of ADRs related to the above mentioned drugs are substantially evidenced in literature, pre-emptive pharmacogenetic analysis has not yet found its way into common clinical practice.

The enzymes of the cytochrome P450 superfamily play a critical role in phase I drug metabolism. Among them, CYP2C9 and CYP2C19 are clinically important, as they can mediate severe toxicity, therapy failure, and increased susceptibility to cancer and other diseases caused by chemicals. The aim of this study was to determine the prevalence of pharmacologically most important allelic variants of the CYP2C9 and CYP2C19 genes in the general population of the Republic of Srpska (Bosnia and Herzegovina) and to compare them with other populations. For this purpose we determined the genotype profile and allele frequency of 216 randomly selected healthy volunteers using real-time polymerase chain reaction (RTPCR). The prevalence of the CYP2C9 *2 and *3 alleles was 13.6 and 7.4 %, respectively. Based on these frequencies, of the 216 participants four (1.86 %) were predicted to be poor metabolisers, 78 (36.11 %) intermediate, and the remaining 134 (62.03 %) normal metabolisers. Based on the prevalence of CYP2C19 *2 and *17 variants – 16.2 and 20.4 %, respectively – nine (4.17 %) were predicted to be poor, 57 (26.39 %) rapid, and nine (4.17 %) ultra-rapid metabolisers. We found no significant differences in allele frequencies in our population and populations from other European countries. These findings suggest that genetically determined phenotypes of CYP2C9 and CYP2C19 should be taken into consideration to minimise individual risk and improve benefits of drug therapy in the Republic of Srpska., Citokrom P450 (CYP) visokopolimorfna je superobitelj enzima s ključnom ulogom u metabolizmu lijekova, masnih kiselina, steroida i ksenobiotika. U okviru spomenute skupine enzimi CYP2C9 i CYP2C19 prepoznati su kao klinički važni jer sudjeluju u prvoj fazi metabolizma lijekova te mogu dovesti do neadekvatnoga terapijskog odgovora, toksičnosti i pojave određenih bolesti. Cilj istraživanja je bio odrediti genotipove i prevalenciju alela u 216 nasumice odabranih zdravih ispitanika u populaciji Republike Srpske (Bosna i Hercegovina), te rezultate usporediti s drugim populacijama. Genotipovi enzima CYP2C9 i CYP2C19 određeni su metodom lančane reakcije polimeraze u realnom vremenu (eng. real-time PCR). Prema protokolu proizvođača, korištene su Taqman početnice i probe (engl. Taqman SNP genotyping assay). Kod CYP2C9, učestalosti alela *2 i *3 su 13,6 odnosno 7,4 %. Od 216 sudionika, njih četvero (1,86 %) spori su metabolizatori, a većina njih (62,03 %) normalni metabolizatori. Što se tiče CYP2C19, učestalosti alela *2 i *17 su 16,2 odnosno 20,4 %. Od ukupnoga broja sudionika, njih devet (4,17 %) spori su metabolizatori, njih 57 (26,39 %) brzi metabolizatori, a devet je sudionika (4,17 %) okarakterizirano kao ultrabrzi metabolizatori. U usporedbi s podatcima o učestalosti genotipova i alelnih varijanti CYP2C9 i CYP2C19 u drugim europskim populacijama, dobiveni rezultati pokazali su veliku sličnost. Rezultati ovog istraživanja upućuju da bi određene terapije trebale uzeti u obzir utvrđene fenotipove CYP2C9 i CYP2C19 prilikom procjene individualnih rizika i dobrobiti primjene.

Diabetes mellitus is a summarizing term for chronic metabolic diseases characterized by long- lasting hyperglycemia. The incidence of type 2 diabetes mellitus is rising worldwide, with the predominant characteristics of a global epidemic in recent years. Treatment of diabetes comprises, among other means, oral antidiabetics, whose function and incidence of side effects can also be influenced by genetic factors. Pharmacogenetics, a field on the border between pharmacology and genetics, deals with such interactions. Pharmacogenetic knowledge helps with drug development and deepens the understanding of the physiological causes of the disease, emphasizing the individuality of the patient. This thesis aims to summarize the pharmacogenetic interactions described in the most used oral antidiabetics so far and their mechanisms of action. Key words: pharmacogenetics, diabetes, gene-environment interactions, single nucleotide polymorphisms

Background. Asthma treatment response is highly variable and pharmacogenetic markers that predict treatment response would be one step closer to personalized treatment. GWAS studies have shown that polymorphisms GLCCI1 could be associated with asthma treatment response to inhaled corticosteroids (ICS). Materials and methods. We genotyped rs37973 of GLCCI1 in 208 adult asthma patients treated with ICS. Change in % predicted FEV1 was analysed after short-term (3 months) and after long-term (at least 3 years) treatment. Treatment success was defined as good when FEV1 decreased less than 30 ml/year. Results. After 3 months of treatment, change of % predicted FEV1 was higher in patients with GG genotype than in patients with AG+AA genotype, and this genotype dependent difference was only evident in non-smokers. Similar results were found after at least 3 years of treatment when all patients were analysed, in non-smokers and patients with atopy. Even though, no differences in treatment success (good vs. poor response) were observed when analysing the entire group of patients, genotype dependent treatment success was highly influenced by smoking and atopy. GG genotype was overrepresented in non-smokers and patients with atopy with good response. Conclusions. Rs37973 was associated with short- and long-term treatment response however, there was a great influence of smoking and atopy on pharmacogenetic association. Furthermore, we found GG genotype to be associated with better treatment response, what is contrary to results found in GWAS.

Cilj: Cilj istraživanja je ispitati stavove studenata medicine, dentalne medicine i farmacije o farmakogenomici i personaliziranoj medicini. Materijal i metode: Istraživanje je provedeno među studentima medicine, dentalne medicine i farmacije Medicinskoga fakulteta Sveučilišta u Splitu. Anketno ispitivanje provedeno je internetskim putem koristeći alat Google forms, zbog epidemiološke situacije uzrokovane epidemijom COVID-19. Rezultati: U istraživanju je sudjelovalo ukupno 415 studenata. Najveći udio uključenih studenata činili su studenti farmacije te studenti pete godine svih studija. Većina je studenata smatrala da geni imaju umjeren utjecaj na zdravlje. Oko 60% studenata smatra da bi farmakogenomika trebala biti važan dio nastavnog programa, dok samo 12,1% studenata smatra da je plan i program za razumijevanje farmakogenomike dobro osmišljen. Gotovo 85% svih studenata smatra da personalizirana medicina predstavlja novi i obećavajući način zdravstvene njege. Zaključak: Ovo istraživanje je pokazalo kako je edukacija vrlo važna za razvoj novih znanja o farmakogenomici. Također, farmakogenomika trebala bi biti više obuhvaćena u nastavnom planu i programu kako bi studenti stekli samopouzdanje i bili spremni primjeniti je u kliničkoj praksi. To bi trebalo olakšati da farmakogenomika i personalizirana medicina postanu novi način zdrastvene njege., Objectives: The aim of the study was to investigate medical, dental and pharmacy students attitudes of pharmacogenomics and personalized medicine. Material and methods: The research was conducted among students of medicine, dental medicine and pharmacy at the School of Medicine, University of Split. The survey was conducted online using the Google forms tool, due to the epidemiological situation caused by the COVID-19 epidemic. The questionnaire consisted of 35 questions. Results: A total of 415 students participated in the study. The largest share of students involved are pharmacy students and fifth-year students of all studies. Most of the students thought that the genes had moderate impact on health. About 60% of students believe that pharmacogenomics should be an important part of the curriculum, while only 12.1% of students believe that the curriculum for understanding pharmacogenomics is well designed. Almost 85% of all students believe that personalized medicine is a new and promising way of health care. Conclusion: This research has shown that education is very important for the development of new knowledge about pharmacogenomics. Also, pharmacogenomics should be more included in the curriculum in order for students to gain self-confidence and be ready to apply it in clinical practice. This should make it easier for pharmacogenomics and personalized medicine to become a new way of health care.