Adverse drug reactions caused by drug-drug interactions reported to Croatian Agency for Medicinal Products and Medical Devices: a retrospective observational study.

AIM: To analyze potential and actual drug-drug interactions reported to the Spontaneous Reporting Database of the Croatian Agency for Medicinal Products and Medical Devices (HALMED) and determine their incidence. METHODS: In this retrospective observational study performed from March 2005 to December 2008, we detected potential and actual drug-drug interactions using interaction programs and analyzed them. RESULTS: HALMED received 1209 reports involving at least two drugs. There were 468 (38.7%) reports on potential drug-drug interactions, 94 of which (7.8% of total reports) were actual drug-drug interactions. Among actual drug-drug interaction reports, the proportion of serious adverse drug reactions (53 out of 94) and the number of drugs (n=4) was significantly higher (P<0.001) than among the remaining reports (580 out of 1982; n=2, respectively). Actual drug-drug interactions most frequently involved nervous system agents (34.0%), and interactions caused by antiplatelet, anticoagulant, and non-steroidal anti-inflammatory drugs were in most cases serious. In only 12 out of 94 reports, actual drug-drug interactions were recognized by the reporter. CONCLUSION: The study confirmed that the Spontaneous Reporting Database was a valuable resource for detecting actual drug-drug interactions. Also, it identified drugs leading to serious adverse drug reactions and deaths, thus indicating the areas which should be in the focus of health care education.

Smart Safety Surveillance (3S): Multi-Country Experience of Implementing the 3S Concepts and Principles.

INTRODUCTION: The Smart Safety Surveillance (3S) concept is based on the understanding that, when faced with competing pharmacovigilance priorities, countries will have to invest judiciously, by focusing on new priority products, sharing work and resources with other countries when possible and building national competence for those activities that cannot be delegated. METHOD: The 3S principles were applied to Armenia, Brazil, Ethiopia, India, Peru and Thailand using three priority products: bedaquiline, rotavirus vaccine and tafenoquine. A baseline assessment of pharmacovigilance preparedness was used to identify gaps and establish a work plan. The impact was measured by comparing pre and post 3S-intervention outcomes, which included the number and quality of reports (completeness scores) in the WHO global database of Individual Case Safety Reports, VigiBase, and number of structural indicators met. The implementation period was 9-18 months, ranging from March 2018 (earliest started) until May 2020 (latest). RESULT: An increase in adverse drug reaction (ADR) reporting was demonstrated in Armenia (bedaquiline), Brazil (TB and malaria medicines), India (rotavirus vaccine) and Ethiopia (TB medicines). Completeness scores were above 0.5 at baseline in all countries, and reports improved in quality for Brazil (TB), Peru (malaria), Thailand (malaria) and India (immunization). The number of structural indicators met increased by more than double for Ethiopia. Ethiopia and India demonstrated an increased capacity for signal detection and signal evaluation. Armenia, Brazil, Peru and Thailand showed increased capacity to assess risk management plans following the implementation of 3S principles. CONCLUSION: The 3S concept has demonstrated success in different ways across the six countries. Activities focused on three products for a proof of concept of the 3S principles, with the expectation that the project impact will be sustained through strengthened systems, to guide pharmacovigilance activities of other products in the future. It is important to continue monitoring the countries to understand if the gains and successes of the current 3S project are sustainable.

Regulating medicines in Croatia: five-year experience of Agency for Medicinal Products and Medical Devices.

AIM: To present the activities of the Agency for Medicinal Products and Medical Devices in the first 5 years of its existence and to define its future challenges. METHODS: Main activities within the scope of the Agency as a regulatory authority were retrospectively analyzed for the period from 2004-2008. Data were collected from the Agency's database and analyzed by descriptive statistics. RESULTS: The number of issued medicine authorizations rose from 240 in 2004 to 580 in 2008. The greatest number of new chemical and biological entities was approved in 2005. The greatest number of regular quality controls (n=5833) and special quality controls was performed in 2008 (n=589), while the greatest number of off-shelf quality controls (n=132) was performed in 2007. The greatest number of medicine labeling irregularities was found in 2007 (n=19) and of quality irregularities in 2004 (n=9). The greatest number of adverse reactions was reported in 2008 (n=1393). The number of registered medical devices rose from 213 in 2004 to 565 in 2008. CONCLUSION: Over its 5 years of existence, the Agency has successfully coped with the constant increase in workload. In the future, as Croatia enters the European Union, the Agency will have to face the challenge of joining the integrated European regulatory framework.

Rosuvastatin-Induced Rhabdomyolysis - Possible Role of Ticagrelor and Patients' Pharmacogenetic Profile.

Up to the beginning of 2018, a total of eight cases describing rare but clinically important drug interactions between rosuvastatin and ticagrelor which resulted in rhabdomyolysis have been noted in the Global World Health Organization (WHO) adverse drug reaction (ADR) database (VigiBase) as well as in available literature. There are several possible factors which could contribute to the onset of rhabdomyolysis: old age, initially excessive rosuvastatin dose, drug-drug interactions (DDI) on metabolic enzymes (CYPs and UGTs) and drug transporter levels (ABCB1, ABCG2, OATP1B1) and pharmacogenetic predisposition. We reviewed all available cases plus the case of an 87-year-old female Croatian/Caucasian patient who developed rhabdomyolysis following concomitant treatment with rosuvastatin and ticagrelor. The results of the pharmacogenetic analysis indicated that the patient was a carrier of inactivating alleles CYP2C9*1/*3, CYP3A4*1/*22, CYP3A5*3/*3, CYP2D6*1/*4, UGT1A1*28/*28, UGT2B7 -161C/T, ABCB1 3435C/T and ABCB1 1237C/T which could have added to the interactions not only between ticagrelor and rosuvastatin but also other concomitantly prescribed medicines, such as amiodarone and proton pump inhibitors. In this case report, the possible multifactorial causes for rhabdomyolysis following concomitant use of rosuvastatin and ticagrelor such as old age, polypharmacy, renal impairment, along with pharmacogenetics will be discussed.

Vaccine regulations in Croatia.

In this paper legal prerequisites for vaccine licensure in Croatia are discussed. The Croatian legislation concerning vaccine licensing, marketing authorisation and utilization is reviewed. The procedures for including a vaccine into the Mandatory Childhood Vaccination Programme are also discussed with focus on Human papillomavirus (HPV) vaccines. Non-obligatory vaccination recommendations are given when according to professional opinion; vaccination is beneficial for the vaccinee. There is little doubt that HPV vaccines should be recommended for preadolescent girls in Croatia. However, reaching a decision on its possible introduction into the Childhood Vaccination Programme will require careful consideration of the larger picture and a comparison of the cost-effectiveness of a mandatory vaccination against other competing public health priorities.

A retrospective review of paediatric adverse drug reactions reported in Lombardy and Croatia from 2005 to 2013.

OBJECTIVE: to characterise the adverse drugs reactions (ADRs) reported in the Lombard and Croatian paediatric population and to compare data to specific paediatric age groups, in terms of trend, pattern and severity of ADRs, increasing understanding of paediatric ADRs. RESEARCH DESIGN AND METHODS: We selected and analysed all the spontaneous reports in which children were involved (0 < 18 years old) reported in the Lombardy and in Croatian pharmacovigilance databases from 1th March 2005 to 31th December 2013. RESULTS: 9175 ADR reports were reported in the Lombardy, 2457 were included in the Croatian database. The age groups most involved were 2-11 for both countries. The 13.2% and 40.3% of reports retrieved in Lombardy and Croatia were classified as serious, respectively. Fatalities account for 0.09% and 0.12% in Lombardy and Croatia, respectively. CONCLUSION: Data on serious reports reflect a similar scenario in terms of age range; strikingly different therapeutic subgroups were involved in reporting activity likely due to greater self-medication practices with penicillins and anti-inflammatory, analgesic and antipyretics drugs in Lombardy than in Croatia, highlighting the need to closely monitor this paediatric therapeutic area to ensure a safe use of these drugs.

Clinical Application of Genotype-guided Dosing of Warfarin in Patients with Acute Stroke.

BACKGROUND: Patients with certain types of stroke need urgent anticoagulation and it is extremely important for them to achieve fast and stable anticoagulant effect and receive individualized treatment during the initiation of warfarin therapy. METHODS: We conducted a prospective study among 210 acute stroke patients who had an indication for anticoagulation and compared the impact of CYP2C9 and VKORC1 genotype-guided warfarin dosing (PhG) with fixed dosing (NPhG) on anticoagulation control and clinical outcome between groups. RESULTS: PhG achieved target INR values earlier, i.e., on average in 4.2 (4.1-4.7, 95% CI) days compared to NPhG (5.2 days [4.7-6.4, 95% CI]) (p = 0.0009), spent a higher percentage of time in the therapeutic INR range (76.3% [74.7-78.5, 95% CI] vs. 67.1% [64.5-69.6, 95% CI] in NPhG), and spent less time overdosed (INR > 3.1) (PhG 0.4 [0.1-0.7, 95% CI], NPhG 1.7 [1.1-2.3, 95% CI] days; p >0.000). PhG reached stable maintenance dose faster (10 [9.9-10.7, 95% CI] vs. 13.9 [13.3-14.7, 95% CI] days in controls; p = 0.0049) and had a better clinical outcome in relation to neurological deficit on admission as compared to NPhG. CONCLUSION: We confirmed that warfarin therapy with genotype-guided dosing instead of fixed dosing reduces the time required for stabilization and improves anticoagulant control with better clinical outcome in early stages of warfarin therapy introduction among acute stroke patients, which is essential for clinical practice.

ABCG2 gene polymorphisms as risk factors for atorvastatin adverse reactions: a case-control study.

AIM: To explore the association between dose-related adverse drug reactions (ADRs) of atorvastatin and polymorphisms of ABCG2, taking into account the influence of CYP3A4 and SLCO1B1 genes. MATERIALS & METHODS: Sixty patients who experienced atorvastatin dose-related ADRs and 90 matched patients without ADRs were enrolled in the study. Genotyping for ABCG2 421C > A, CYP3A4*22, SLCO1B1 388A > G, SLCO1B1 521T > C variants was performed by real-time PCR. RESULTS: Patients with ABCG2 421CA or AA genotypes had 2.9 times greater odds of developing atorvastatin dose-dependent ADRs (OR: 2.91; 95% CI: 1.22-6.95; p = 0.016) than those with ABCG2 421CC genotype. After adjustments for clinical and genetic risk factors, ABCG2 remained a statistically significant predictor of adverse drug reactions (OR: 2.75; 95% CI: 1.1-6.87; p = 0.03;). Also, carriers of SLCO1B1 521 TC or CC genotypes had 2.3 greater odds (OR: 1.03-4.98; 95% CI: 1.03-4.98; p = 0.043) of experiencing ADRs caused by atorvastatin in comparison with carriers of SLCO1B1 521 TT genotype. CONCLUSION: Our study demonstrated an association between atorvastatin-induced ADRs and genetic variants in the ABCG2 gene.

[Evaluation of justification for antibiotic use at the Internal Medicine Clinic of the Clinical Hospital in Zagreb]. / Procjena opravdanosti potrosnje antibiotika u Klinici za unutrasnje bolesti Klinickog bolnickog centra Zagreb.

OBJECTIVE: Resistance to antimicrobials as the result of unnecessary and inadequate use of antibiotics has become a global health problem. It is estimated that up to 50% of antimicrobials are used unnecessarily, and that they are the cause of approximately 25% of adverse drug reactions. Efforts are made to ensure a controlled use of antibiotics, which is the key strategy against development of resistance to antimicrobials. Since antimicrobial drugs are among the most commonly prescribed drugs in hospitals, a rational use of antibiotics would also help reduce health care costs. There are limited data on the use of antibiotics in Croatian hospitals. METHODS: This observational study was conducted at the University Department of Medicine, Zagreb University Hospital Center, with the aim to investigate the prevalence of antimicrobial use, indications for antibiotic use, and the necessity and adequacy of antibiotic therapy. The investigated parameters were: prescribed antibiotic (dose, route of administration, duration of therapy), indication for use of antibiotics (prophylaxis, treatment), diagnosis, presence of positive culture, indication documented in medical records, evaluation of antibiotic therapy by a specialist, and risk factors. The most important parameter in the evaluation of the necessity of antimicrobial use was the presence of culture days of treatment, and indication for treatment documented in medical records and evaluated by a specialist. The data were collected over 1 day using a standardized questionnaire. RESULTS: Fifty of 138 (37%) hospitalized patients were receiving 1 or more antibiotics, most of them (80%) for the treatment of infection. The most frequent diagnoses were sepsis (64%), urinary tract infection (25%), abdominal infection (21%), and pulmonary infection (7%). The median therapy duration was 4 days (minimum 1 day, maximum 121 days). The most frequently prescribed antibiotics were fluoroquinolones (23%), penicillins (23%), aminoglycosides (18%) and cephalosporins (11%). Thirty-nine patients received one or more reserve antibiotics. The median number of received antibiotics was 2 (minimum 1, maximum 5 antibiotics). Risk factors were present in 76% of patients. Fifty-nine percent patients were receiving antibiotics on the basis of culture; in most of them therapy was evaluated by a specialist (98%) and the indication was documented in medical records. Reserve antibiotics were prescribed in 34 patients, in 77% of them on the basis of positive culture. CONCLUSION: The high prescription rate of antibiotics (fluoroquinolones), concomitant use of antibiotics of a similar spectrum of activity and lack of sequential therapy emerged to be the parameters needing further evaluation. Other investigated parameters (number of antibiotics, duration of therapy, necessity of antibiotic therapy) were in accordance with similar studies conducted in hospitals. Further investigation with emphasis on local problems and prescription habits with the aim to optimize the use of antibiotics is needed.

CYP2C9 and ABCG2 polymorphisms as risk factors for developing adverse drug reactions in renal transplant patients taking fluvastatin: a case-control study.

AIM: To investigate whether an association exists between fluvastatin-induced adverse drug reactions (ADRs) and polymorphisms in genes encoding the metabolizing enzyme CYP2C9 and the drug transporter ABCG2 in renal transplant recipients (RTRs). MATERIALS & METHODS: Fifty-two RTRs that experienced fluvastatin ADRs and 52 controls matched for age, gender, dose of fluvastatin and immunosuppressive use were enrolled in the study. Genotyping for CYP2C9*2, *3 and ABCG2 421C>A variants was performed by real-time PCR. RESULTS: CYP2C9 homozygous and heterozygous mutant allele (*2 or *3) carriers had 2.5-times greater odds of developing adverse effects (χ² = 4.370; degrees of freedom = 1; p = 0.037; φ = 0.21, odds ratio [OR]: 2.44; 95% CI: 1.05-5.71). Patients who were the carriers of at least one mutant CYP2C9 allele (*2 or *3) and who were receiving CYP2C9 inhibitors, had more than six-times greater odds of having adverse effects than those without the inhibitor included in their therapy (p = 0.027; OR: 6.59; 95% CI: 1.24-35.08). Patients with ABCG2 421CA or AA (taken together) had almost four-times greater odds of developing adverse effects than those with ABCG2 421CC genotype (χ² = 6.190; degrees of freedom = 1; p = 0.013; φ = 0.24, OR: 3.81; 95% CI: 1.27-11.45). Patients with A allele had 2.75-times (95% CI: 1.02-7.40) greater odds of developing adverse effects than those with C allele. CONCLUSION: Our preliminary data demonstrate an association between fluvastatin-induced ADRs in RTRs and genetic variants in the CYP2C9 and ABCG2 genes.

Use of gastroprotective agents in recommended doses in hospitalized patients receiving NSAIDs: a drug utilization study.

OBJECTIVE: In recent years, studies investigated to what extend recommendations for co-prescribing gastroprotective agents in prevention of NSAID-induced gastrointestinal complications are followed in clinical practice. However, only a few studies have also taken into consideration the recommended dose of gastroprotectives prescribed in NSAID-induced ulcer prophylaxis. The aim of our study was to evaluate the prevalence of concomitant use of gastroprotectives with NSAIDs in hospitalized patients, with emphasis on the recommended dose of gastroprotectives for ulcer prophylaxis. METHOD: This observational, cross-sectional, drug utilization study included all adult patients receiving NSAIDs hospitalized in the Clinical Hospital Center Zagreb on the day of the study. Data on age, sex, comorbidities, indications for NSAID use, type/dose of NSAIDs and gastroprotectives, history of gastrointestinal events, active gastrointestinal symptoms and risk factors were evaluated. MAIN OUTCOME MEASURE: Study outcomes were: (1) prevalence of prescription of gastroprotectives among NSAID-users at risk; (2) prevalence of prescription of gastroprotective in recommended dose; (3) association between risk factors and prescription of GPAs. RESULTS: The rates of gastroprotectives prescription were significantly higher in NSAID-users with concomitant risk factors as compared to patients without risk factors [47/70 (67.1%) and 8/22 (36.4%), respectively; p=0.01072]. However, gastroprotection in recommended ulcer-preventive dose was low in both groups [8/70 (11.4%) and 9/92 (9.8%), respectively]. The number of concomitant risk factors did not increase the odds of receiving anti-ulcer therapy (odds ratio 0.7279). Thirty-three percent of patients with concomitant risk factors were not prescribed gastroprotectives. Ibuprofen, NSAID with the lowest risk of inducing gastrointestinal complications, was prescribed in only two patients. CONCLUSION: The results indicate high awareness among hospital physicians about possible NSAID-induced gastrointestinal complications, but insufficient knowledge about risk factors related to NSAID-induced gastrointestinal toxicity, recommended dose of gastroprotectives in NSAID-induced ulcer prophylaxis and gastrointestinal toxicity of different types of NSAIDs.

Acquired coagulopathy due to anticoagulant rodenticide poisoning.

A 35-year-old woman was admitted to hospital because of epistaxis, hematomas, and metrorrhagia. Laboratory data indicated severe coagulopathy with prolonged prothrombin time and decreased serum concentrations of vitamin K-dependent clotting factors II, VII, IX, and X. The patient denied taking any oral anticoagulants. She was given transfusions of red blood cells, fresh frozen plasma (1,180 mL) and phytomenadione daily for 6 weeks (total dose 550 mg), which normalized the coagulation factors concentration. After all other possible causes of acquired coagulopathy had been excluded, rodenticide poisoning was suspected on the basis of her epidemiologic history. The patient was a war refugee from Bosnia and Herzegovina. During her absence, the troops of United Nations Protection Force performed rodent extermination in and around her house. History data and therapeutic effects suggested that the coagulopathy had been caused by prolonged exposure to long-acting anticoagulant rodenticide. This could also explain the need for protracted phytomenadione therapy.