Konstantins Logviss

Dr. Konstantins Logviss

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

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

Representative Publications

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2 January 2020 in Expert Review of Pharmacoeconomics & Outcomes Research
Verified
Journal Article
Open access
BGBrian Godman
Brian Godman
HMHolly McCabe
Holly McCabe
TLTrudy Leong
Trudy Leong
DMDebjani Mueller
Debjani Mueller
AMAntony P. Martin
Antony P. Martin
Johanna Catharina MeyerJohanna Catharina Meyer
Johanna Catharina Meyer
Introduction: There are positive aspects regarding the prescribing of fixed dose combinations (FDCs) versus prescribing the medicines separately. However, these have to be balanced against concerns including increased costs and their irrationality in some cases. Consequently, there is a need to review their value among lower- and middle-income countries (LMICs) which have the greatest prevalence of both infectious and noninfectious diseases and issues of affordability. Areas covered: Review of potential advantages, disadvantages, cost-effectiveness, and availability of FDCs in high priority disease areas in LMICs and possible initiatives to enhance the prescribing of valued FDCs and limit their use where there are concerns with their value. Expert commentary: FDCs are valued across LMICs. Advantages include potentially improved response rates, reduced adverse reactions, increased adherence rates, and reduced costs. Concerns include increased chances of drug:drug interactions, reduced effectiveness, potential for imprecise diagnoses and higher unjustified prices. Overall certain FDCs including those for malaria, tuberculosis, and hypertension are valued and listed in the country’s essential medicine lists, with initiatives needed to enhance their prescribing where currently low prescribing rates. Proposed initiatives include robust clinical and economic data to address the current paucity of pharmacoeconomic data. Irrational FDCs persists in some countries which are being addressed.

3 October 2023 in Pharmaceuticals
Verified
Journal Article
Open access
PDF file
MBMarta Berga
Marta Berga
KLKonstantins Logviss
Konstantins Logviss
LPLiga Petersone
Liga Petersone
APArturs Paulausks
Arturs Paulausks
Valentyn MohylyukValentyn Mohylyuk
Valentyn Mohylyuk
Flavonoids are hydroxylated polyphenols that are widely distributed in plants with diverse health benefits. Despite their popularity, the bioavailability of flavonoids is often overlooked, impacting their efficacy and the comparison of products. The study discusses the bioavailability-related physicochemical properties of flavonoids, with a focus on the poorly soluble compounds commonly found in dietary supplements and herbal products. This review sums up the values of pKa, log P, solubility, permeability, and melting temperature of flavonoids. Experimental and calculated data were compiled for various flavonoid subclasses, revealing variations in their physicochemical properties. The investigation highlights the challenges posed by poorly soluble flavonoids and underscores the need for enabling formulation approaches to enhance their bioavailability and therapeutic potential. Compared to aglycones, flavonoid glycosides (with sugar moieties) tend to be more hydrophilic. Most of the reviewed aglycones and glycosides exhibit relatively low log P and high melting points, making them “brick dust” candidates. To improve solubility and absorption, strategies like size reduction, the potential use of solid dispersions and carriers, as well as lipid-based formulations have been discussed.

27 December 2023 in Journal of Drug Delivery Science and Technology
Verified
Journal Article
Closed access
ASAndrejs Sitovs
Andrejs Sitovs
KLKonstantins Logviss
Konstantins Logviss
LPLiga Petersone
Liga Petersone
Valentyn MohylyukValentyn Mohylyuk
Valentyn Mohylyuk

3 April 2018 in PLOS ONE
Verified
Journal Article
Open access
PDF file
KLKonstantins Logviss
Konstantins Logviss
DKDainis Krievins
Dainis Krievins
SPSanta Purvina
Santa Purvina
Conducting clinical studies in small populations may be very challenging; therefore quality of clinical evidence may differ between rare and non-rare disease therapies. This register-based study aims to evaluate the characteristics of clinical trials in rare diseases conducted in Latvia and compare them with clinical trials in more common conditions. The EU Clinical Trials Register (clinicaltrialsregister.eu) was used to identify interventional clinical trials related to rare diseases (n = 51) and to compose a control group of clinical trials in non-rare diseases (n = 102) for further comparison of the trial characteristics. We found no significant difference in the use of overall survival as a primary endpoint in clinical trials between rare and non-rare diseases (9.8% vs. 13.7%, respectively). However, clinical trials in rare diseases were less likely to be randomized controlled trials (62.7% vs. 83.3%). Rare and non-rare disease clinical trials varied in masking, with rare disease trials less likely to be double blind (45.1% vs. 63.7%). Active comparators were less frequently used in rare disease trials (36.4% vs. 58.8% of controlled trials). Clinical trials in rare diseases enrolled fewer participants than those in non-rare diseases: in Latvia (mean 18.3 vs. 40.2 subjects, respectively), in the European Economic Area (mean 181.0 vs. 626.9 subjects), and in the whole clinical trial (mean 335.8 vs. 1406.3 subjects). Although, we found no significant difference in trial duration between the groups (mean 38.3 vs. 36.4 months). The current study confirms that clinical trials in rare diseases vary from those in non-rare conditions, with notable differences in enrollment, randomization, masking, and the use of active comparators. However, we found no significant difference in trial duration and the use of overall survival as a primary endpoint.

18 September 2014 in Orphanet Journal of Rare Diseases
Verified
Journal Article
Open access
PDF file
KLKonstantins Logviss
Konstantins Logviss
Dainis KrievinšDainis Krievinš
Dainis Krievinš
SPSanta Purvina
Santa Purvina
Ten years have passed since Latvia became a Member State of the EU in 2004. As a result European regulations, including those related to rare diseases and orphan drugs, have been applied to Latvian legislative system. Orphan diseases have been recognized as a priority area for action in the public health system, though there are significant differences in the national healthcare services for rare diseases among the EU States. This study aims to determine situation in the field of rare diseases in Latvia and compare it with other European countries. We used the national plan for rare diseases, EUCERD reports, Orphanet data, Latvian and European regulations, publicly available data from the state agencies, and directly contacted drug manufacturers and wholesalers. National plan for rare diseases was developed and approved in 2013. Although there are no official designated centers of expertise as well as no specific register for rare diseases. Newborns are screened for only two disorders: phenylketonuria and congenital hypothyroidism. Currently 34 orphan drugs are available on Latvian market. Three medicines (8.8%) are included in the reimbursement drug list, all indicated for Ph + CML. 15 drugs (44.1%) were reimbursed within the framework of individual reimbursement system, and five drugs (14.7%) were provided within the program of medicinal treatment of rare diseases in children. Majority of orphan drugs authorized in the EU are not available in Latvia, moreover those drugs that are available are often not accessible because they are insufficiently reimbursed. Besides, approval of the national plan might be an important step towards improving situation in the field of rare diseases.

11 May 2016 in Orphanet Journal of Rare Diseases
Verified
Journal Article
Open access
PDF file
KLKonstantins Logviss
Konstantins Logviss
DKDainis Krievins
Dainis Krievins
SPSanta Purvina
Santa Purvina
Number of orphan medicinal products on the market and number of rare disease patients, taking these usually expensive products, are increasing. As a result, budget impact of orphan drugs is growing. This factor, along with the cost-effectiveness of orphan drugs, is often considered in the reimbursement decisions, directly affecting accessibility of rare disease therapies. The current study aims to assess the budget impact of orphan drugs in Latvia. Our study covered a 5-year period, from 2010 to 2014. Impact of orphan drugs on Latvian budget was estimated from the National Health Service’s perspective. It was calculated in absolute values and relative to total pharmaceutical market and total drug reimbursement budget. A literature review was performed for comparison with other European countries. Orphan drug annual expenditure ranged between EUR 2.065 and 3.065 million, with total 5-year expenditure EUR 12.467 million. It constituted, on average, 0.84 % of total pharmaceutical market and 2.14 % of total drug reimbursement budget, respectively. Average annual per patient expenditures varied widely, from EUR 1 534 to EUR 580 952. The most costly treatment was enzyme replacement therapy (Elaprase) for MPS II. Glivec had the highest share (34 %) of the total orphan drug expenditure. Oncological drugs represented more than a half of the total orphan drug expenditure, followed by drugs for metabolic and endocrine conditions and medicines for cardiopulmonary diseases. Three indications: Ph+ CML, MPS II, and PAH accounted for nearly 90 % of the total orphan drug expenditure. Budget impact of orphan drugs in Latvia is very small. It increased slightly over a period of five years, due to the slight increase in the number of patients and the number of orphan drugs reimbursed. Current Latvian drug reimbursement system is not sufficient for most orphan drugs.