Valentina Petkova

Prof. Dr. Valentina Petkova

MEDICAL UNIVERSITY, Sofia, Sofia-Grad, Bulgaria
orcid

Research Focus & Metrics

Academic Career Length

65Years (1962-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2012 in Biotechnology & Biotechnological Equipment
Verified
Journal Article
Closed access
INIrina Nikolova Nikolova
Irina Nikolova Nikolova
JTJasmina Tencheva
Jasmina Tencheva
JVJulian Voinikov
Julian Voinikov
VPValentina Petkova
Valentina Petkova
NBNiko Benbasat
Niko Benbasat
NDNikolai Danchev
Nikolai Danchev

21 November 2023 in Pharmaceutics
Verified
Journal Article
Open access
PDF file
VPValentina Petkova
Valentina Petkova
DGDilyana Georgieva
Dilyana Georgieva
Milen Ventsislavov DimitrovMilen Ventsislavov Dimitrov
Milen Ventsislavov Dimitrov
INIrina Nikolova Nikolova
Irina Nikolova Nikolova
Off-label prescribing is widespread among pediatricians, and it is unlikely that this trend will soon be bound by a uniform legal framework. This is necessitated by the fact that there are four variables: the patient’s health condition, the physician’s experience and knowledge, the legislative measures (laws, directives, guidelines, and recommendations), and finally, the pharmaceutical industry. There is considerable concern worldwide about the use of off-label medicines in children. We may call it an enormous global problem that is much talked about and written about; however, we should not forget that the goal around which everyone should unite is the patient’s life. For healthcare providers, the most important thing will always be the health and preservation of the patient’s life, particularly when it comes to children with life-threatening conditions in neonatal and pediatric intensive care units (NICU and PICU). The study aimed to examine the prevalence of off-label drug use in pediatrics. Literature research was conducted, and we included studies from 2012 to 2022 that evaluated off-label drug prevalence in various pediatric patient populations.

1 January 2013 in Biotechnology & Biotechnological Equipment
Verified
Journal Article
Closed access
INIrina Nikolova Nikolova
Irina Nikolova Nikolova
VPValentina Petkova
Valentina Petkova
JTJasmina Tencheva
Jasmina Tencheva
NBNiko Benbasat
Niko Benbasat
JVJulian Voinikov
Julian Voinikov
NDNikolai Danchev
Nikolai Danchev

1 January 2008 in Allergy and Asthma Proceedings
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Journal Article
Closed access
VPValentina Petkova
Valentina Petkova
Asthma is a clinical problem with social, psychological, and economic burdens. To improve patient disease management and quality of life (QOL), different education programs have been developed. The purpose of this study is to adapt and implement a community-based educational program for patients with asthma. A prospective, randomized, controlled trial was performed. Fifty individuals with mild asthma (aged 18–40 years) that have been attending pharmacies were included in the sample. The duration of the disease was 9 ± 4.21 years. A 4-month study was conducted on essence of asthma and factors that can intensify it; nourishing facts, allergens, and physical activities; self-management and use of tobacco; and pharmacotherapy, inhalation technique, and possible adverse drug reactions. Patient's health-related QOL was assessed in the beginning and at the end of the survey. Parameters assessed during the four stages of the program were patients' peak expiratory flow (PEF); inhaler technique; severe asthma symptoms, including breathlessness, hospitalization rates, frequency of urgent medical aid calls, and frequency of general practitioner visits; compliance with therapy; and satisfaction with pharmacy services. Health-related QOL of the intervention patients was improved at 4 months and there was improvement in the PEF rate, decrease in patients' breathlessness and wheezing rate, decrease in the reported hospitalizations rate because of the disease, decrease in the physician's visits, and increase in satisfaction with pharmacist-provided information. The positive results from the educational approach show a potential to decrease asthma disease complications and show a positive impact on patients' inhaler technique, patients' opinions about the pharmacy services, and information obtained.

20 September 2018 in Frontiers in Pharmacology
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Journal Article
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MMManoela Manova
Manoela Manova
ASAlexandra Savova
Alexandra Savova
MVMaria Vasileva
Maria Vasileva
STSilvia Terezova
Silvia Terezova
MKMaria Kamusheva
Maria Kamusheva
Guenka PetrovaGuenka Petrova
Guenka Petrova
Biological products for treatment of rheumatoid arthritis usually are cost effective for healthcare systems in Europe, but they are huge financial burden due to the high number of patients and the significant budget impact. The expected saving from introduction on the market of biosimilars are significant and are linked to better access and affordability. The aim of this study was to conduct comparative price analysis of biological products for rheumatoid arthritis therapy among seventeen EU countries. The point of view is that of the Bulgarian pricing and reimbursement system and the chosen countries are those from external reference basket for prices comparison at manufacturing level. All authorized biological products by EMA with therapeutic indication rheumatoid arthritis were selected. The access for treatment is evaluated as the availability of the product on the market and the prices level. We assessed the availability of all trade names in the price lists of the observed countries. The prices data was obtained from the official web pages of the responsible institutions up to date December 2017. The results show that four out of all six INNs have authorized biosimilars in EMA. Despite its earlier authorization biosimilar adalimumab is not present in any of the price lists of countries. From all eighteen countries only in Lithuania and Estonia there were no published prices of any of the selected medicinal products. Countries with higher number of biosimilar prices are Spain and France. Differences in manufacturers’ prices of reference biological products in selected countries in comparison with the lowest manufacturer price are higher with 22 to 69% while the retail prices between 62 and 95%. Differences are mostly notable for rituximab, and less notable for tocilizumab. Manufacturers’ and retail prices of biosimilar products were established only for three INNs (etanercept, rituximab, and infliximab). Manufacturers’ prices differ between 26 and 75%, while retail prices differ between 40 and 92% for biosimilars. Comparison of the differences between manufacturer prices of reference biological product and biosimilars shows 36% difference for etanercept, 39% for rituximab, and 31% for infliximab, while at retail level the differences are 11, 86, and 143%, respectively. The limitation of the study is that the prices are the official ones without discounts due to confidentiality and the real prices may be lower. The second limitation is that the methodology for pricing differs in the countries and this could also influence the prices on both levels (manufacturer and retail). Introduction of biosimilars on the national markets led to significant decrease in reimbursed prices paid by public funds and thus might benefit the patients’ access to biological therapy. The decrease of prices after biosimilars entrance on the market is not as notable as for commodity generics.

2 July 2023 in Pharmaceutics
Verified
Journal Article
Open access
PDF file
SISofiya Ilieva
Sofiya Ilieva
DGDilyana Georgieva
Dilyana Georgieva
VPValentina Petkova
Valentina Petkova
Milen Ventsislavov DimitrovMilen Ventsislavov Dimitrov
Milen Ventsislavov Dimitrov
Three-dimensional (3D) printing has emerged as a new promising technique for the production of personalized dosage forms and medical devices. Polyvinyl alcohol is prominently used as a source material to produce 3D-printed medicines via fused deposition modeling (FDM)—a technology that combines hot melt extrusion and 3D printing. A preliminary screening of three grades of PVA indicated that partially hydrolyzed PVA with a molecular weight (MW) of 31,000–50,000 and plasticized with sorbitol was most suitable for 3D printing. Paracetamol was used as a model drug. The materials and the produced filaments were characterized by X-ray powder diffraction (XRPD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The complex viscosity (η*) of the polymer melts was determined as a function of the angular frequency (ω) at the printing temperature to assess their printability. Three-dimensional printlets with a 40% infill exhibited an immediate release of the API, while tablets with a higher infill were prone to a prolonged release regardless of the filament drug loading. A factorial design was used to give more insight into the influence of the drug-loading of the filaments and the tablet infill as independent variables on the production of 3D printlets. The Pareto chart confirmed that the infill had a statistically significant effect on the dissolution rate after 45 min, which was chosen as the response variable.