Bacteriophages are promising antibacterial agents for managing acne vulgaris caused by Cutibacterium acnes, particularly given increasing antibiotic resistance. Here, we isolated and characterized two lytic Cutibacterium phages, NS-ph1 and NS-ph2, from acne lesions. Both bacteriophages exhibited a broad lytic spectrum, with a high activity against 27 C. acnes strains. Adsorption assays indicated rapid attachment and one-step growth experiments revealed latent periods of 4 h (NS-ph1) and 2 h (NS-ph2) and burst sizes of 70 and 59 PFU per infected cell, respectively. After long-term storage at room temperature, both phages retained infectivity for 3 months. Genome sequencing revealed linear dsDNA genomes of 29,490 bp (NS-ph1) and 29,189 bp (NS-ph2) with 51 and 46 predicted ORFs, respectively, and no tRNAs. No genes associated with lysogeny, toxins, or antibiotic resistance were detected. Comparative genomics placed both phages within the genus Pahexavirus. Together, these data expand the diversity of Pahexavirus and provide two well-characterized lytic candidates for further evaluation in anti-acne phage therapy.

Introduction. The use of antibiotics in the treatment of infectious diseases has led to significant achievements in medicine, but the problem of microbial resistance to antibiotics and the need to develop new antibacterial drugs remain extremely relevant today. One of the promising areas in combating this problem is the search for antimicrobial substances among plant raw materials. This study focused on the substance sangviritrin, which has pronounced antimicrobial properties. Aim. The aim of the study was to investigate the technological and therapeutic characteristics of an oral dosed spray of sangviritrin for the treatment of infectious and inflammatory diseases of the oral cavity. Materials and methods. The object of the study was an oral metered spray of sangviritrin, packaged in 30 ml light-protective glass bottles (LLC "TС "BELAND", Russia) 30 ml polyethylene bottles (LLC "SRP Group", Russia), and LF plastic nozzles (Shenzhen Bona Pharma Technology Co., Ltd., China). The minimum filling volume of the bottle, requirements for primary and secondary pumping, and requirements for nozzle cleaning were determined. The substances extracted from the packaging were studied using high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS), gas chromatography-mass spectrometry (GC-MS), and inductively coupled plasma mass spectrometry (ICP-MS). The stability of the spray was determined in long-term and accelerated tests. The antimicrobial activity of the sangviritrin spray was determined for 21 strains of microorganisms. Results and discussion. The minimum filling volume of the vial was 31 ml. It was shown that there are no requirements for priming the spray dispenser, cleaning the dispenser after use, or shaking. Extractable substances from Russian-made polyethylene bottles were studied using HPLC-MS, GC-MS, and IS-MS methods. The experiment demonstrated that these substances are present in concentrations below the threshold value and cannot adversely affect the safety of the drug. Long-term studies have demonstrated the stability of the developed dosage form for 12 months, and accelerated testing has determined the shelf life of the spray to be 2 years. An in vitro study of the antimicrobial activity of sangviritrin spray using a spot test showed its effectiveness against 18 strains of bacteria and three strains of Candida fungi. Conclusion. The developed dosage form is stable during storage, methods for controlling its quality have been determined, the choice of packaging is justified, and this drug is promising for use in the treatment of inflammatory diseases of the oral cavity.

Herbarium. 2026;3(1):23–32. (In Russ.) https://doi.org/10.33380/3034-3925-2026-3-1-52 . Published: 16.01.2026.

Ribavirin has been used as an antiviral agent to treat a variety of viral infections since the 1970s. Over the past few decades, studies have been conducted on the pharmacology of ribavirin, and the possibility of its use in new indications has been explored. According to the results of a number of studies, ribavirin efficacy in the therapy of malignant neoplasms of various genesis has been proven. Furthermore, due to the complexity of brain tumor therapy using surgical methods, targeted delivery of ribavirin to the brain becomes a promising alternative to existing treatment methods. Targeting of active pharmaceutical ingredient (API) to the brain tumor is achieved by intranasal drug delivery via a Nose-to-Brain mechanism. In addition, using this delivery mechanism, it is possible to reach the brain while bypassing the blood-brain barrier (BBB), thus avoiding the effects of the first passage through the liver. Despite the significant advantages of the method, there are limiting factors to its application - mucociliary clearance, which aims to remove foreign bodies from the surface of the nasal mucosa. In situ, systems are able to reduce the intensity of interfering factors on API and allow the achievement of maximum bioavailability during intranasal administration.

Introduction. The problem of pain relief after surgery is relevant in modern dentistry, as pain control is an important part of treatment. In addition to anesthesia, there are other problems of post-resection therapy such as bleeding from the wound and inflammation. Modern dental practice does not have a targeted delivery system or a medical product with analgesic, anti-inflammatory, anesthetic or hemostatic action, which ensures high adherence of patients to the ongoing post-resection therapy. Text. To solve this problem, it can be proposed to develop an in situ implant – a dosage form that is formed directly at the injection site, in the alveolar socket. Targeted delivery system has advantages: no need to use a medical dressing material; no risk of secondary contamination; dosing accuracy and target delivery to the lesion locus; high mucoadhesion to the site of application; the duration of the active ingredient release and others. The purpose of the review is to substantiate the possibility and relevance of developing a new in situ implant system for use in dental post-resection practice. The study was conducted on the main databases of publications (Scopus, Web of Science, PubMed and others), and patent search database on materials published from 2000 to the present. The study describes the currently existing in situ systems for dental problems, which could be a prototype of systems for delivering an anesthetic directly to the tooth socket, the polymers used to create them and the possibility of releasing drugs, and also characterizes existing drugs for the pain relief (applied both locally and for systemic action), in comparison with in situ systems, which have certain advantages and great potential for development. Conclusion. Based on the results of the work, a conclusion about the possibility of pharmaceutical development of dental in situ implants was made, and the most promising polymers for phase transition in the alveolar socket were identified.

Introduction . Emuxol-268 (JSC "NIOPIK", Russia) is a block copolymer produced in Russia with similar in physicochemical and biological properties to poloxamer Kolliphor® P 188 (Pluronic F68) manufactured by BASF, USA. However, a comparison of the properties of natural polymers to assess the prospects of their dosage forms has not been carried out before. Aim . The aim of the study was to demonstrate the interchangeability of auxiliary components using the example of the development of an ophthalmic drug insert by comparing the results of testing the dosage form in terms of such quality parameters as elasticity, thickness, mucoadhesion, pH, biodegradation time and irritation test (hen’s egg-chorioallantoic membrane test, HET-CAM test). Materials and methods . Poloxamers Emuxol 268 (JSC "NIOPIK", Russia) and Kolliphor® P 188 (BASF, Germany), hydroxyethyl cellulose (Natrosol™ 250 HHX, Ashland Global Holdings Inc., USA), and glycerol (LLC "Tulskaya Pharmfabrika", Russia) were used in the experiment. Elasticity, thickness, mucoadhesion, pH, biodegradation time, HET-CAM test were used as screening methods to identify the benefits of the composition. Results and discussion . Experiment results proved that the use of a domestic analogue makes it possible to create an ocular insert with improved quality parameters. The difference in the elasticity index of the inserts differs by 1.3 times, mucoadhesion – 1.7 times, biodegradation time – 2.5 times. In this connection, it can be assumed that an insert based on a domestic polymer contributes to an increase in the time of contact with the eye surface, thereby providing a prolonged effect of the drug and improving its bioavailability. The results obtained may be due to the difference in the average molecular weight of the hydrophobic polyoxypropylene part, which is 2600 Da for Emuxol 268 and 1800 Da for Kolliphor 188. The HET-CAM method showed the same results of the two compositions, both compositions do not have an irritating effect. Conclusion . Summing up, the only analogue of Kolliphor® P 188 available on the Russian pharmaceutical market – Emuxol-268 of JSC NIOPIK is a promising substance for replacement in the development of ophthalmic dosage forms. Despite the differences in physicochemical properties of the domestic block copolymer in comparison with the replaced poloxamer 188, its introduction into placebo inserts gave improved results in terms of quality indicators, which was revealed during a biopharmaceutical analysis.

Introduction. Medical clays are polymineral sorbents with a predominance of the underlying clay mineral, the concentration of which determines the quality of mineral raw materials and its adsorption activity. One of the methods of improving the quality of mineral raw materials is its activation by means of ultrasonic treatment.Aim. To study the effect of ultrasound on the activation and adsorption activity of mineral sorbents.Materials and methods. Clinoptilolite mineral raw materials of the Kholinsky deposit, montmorillonite mineral raw materials of the Belgorod deposit and kaolinite mineral raw materials of the Eleninsky deposit were used as objects of research. A high-frequency UZDN-1 unit was used for ultrasonic treatment. Determination of adsorption activity was carried out by methylene blue.Results and discussion. The effect of ultrasound on the activation of mineral sorbents at an ultrasonic wave frequency of 40 kHz for five minutes has been studied. It was found that the average content of Clinoptilolite, taking into account all fractions in the clay of the Kholinsky deposit, increases by 20 %, the average content of Montmorillonite, taking into account all fractions in the clay of the Belgorod deposit, increases by 14 %, the average content of Kaolinite, taking into account all fractions in the clay of the Eleninsky deposit, increases by 18 %. The effect of ultrasound on the adsorption activity of mineral sorbents has been investigated. The use of ultrasonic treatment increases the adsorption activity of mineral sorbents by 12–19 %.Conclusion. The developed method of activation of mineral sorbents by ultrasonic treatment can be used to activate mineral sorbents by increasing the concentration of the underlying mineral (Clinoptilolite, Montmorillonite, Kaolinite), as well as increasing their adsorption activity.

In recent years, stimulus-sensitive drug delivery systems have been developed for parenteral administration as a depot system. In situ systems incorporate smart polymers that undergo a phase transition at the site of administration. All parenteral and ocular dosage forms must meet sterility requirements. Careful selection of the sterilization method is required for any type of stimuli-sensitive system. Current sterilization methods are capable of altering the conformation of polymers or APIs to a certain extent, ultimately causing the loss of pharmacological and technological properties of the drug. Unfortunately, the issues of risk assessment and resolution regarding the sterilization of stimuli-sensitive systems, along with ways to stabilize such compositions, are insufficiently described in the scientific literature to date. This review provides recommendations and approaches, formulated on the basis of published experimental data, that allow the effective management of risks arising during the development of in situ systems requiring sterility.

Xyloglucan is a highly promising ‘green’ polymer that has found its application in the food and pharmaceutical industries. Due to its molecular structure similarity to mucin, it has remarkable mucoadhesion properties, which has led to a high research interest in this excipient for the development of transmucosal delivery systems. Thermosensitivity is another promising property of xyloglucan derivatives, which is mainly exhibited by synthetic block copolymers such as pluronics and PLGA derivatives. Delivery systems whose mechanism of active ingredient release is based on temperature sensitivity are widely used in many medical fields, ranging from antitumour therapy to intranasal delivery. Thus, conducting research on the possibility of obtaining and using a new mucoadhesive, fully biocompatible and affordable polymer—xyloglucan—is a promising task.

Introduction . Nowadays block copolymers of PEO and PPO (poloxamers, pluronics, proxanols) are among the most popular polymers in the pharmaceutical and biotechnological industries. They can be applied as effective nonionic surfactants, biological membrane stabilizers, elements of targeted delivery systems, solubilizers, as well as excipients in the technology of traditional dosage forms – gelling agents, lubricants, etc. For the past fifty years, the world's largest manufacturer of poloxamers has been the German chemical concern BASF. However, today in the Russian Federation there is a risk of defects, which defines the relevance of import substitution of this excipient. Text . The purpose of this review is to highlight the experience of production and implementation of PEO and PPO block copolymers into novel Russian scientists’ developments, comparing them with the experience of foreign research groups, which is necessary to assess the potential for import substitution. PEO and PPO block copolymers have been known in the Soviet Union since the late 60s as far as they are mentioned in textbooks of 1964 and 1973. Domestic block copolymers of PEO and PPO have been used in the oil refining industry, as well as in some branches of light industry and in the decontamination of radioactive waste. The unique domestic synthesis of PEO and PPO block copolymers was established in 1978 on the basis of the "Orgsintez" factory. Soviet poloxamers were produced under the brand name "proxanol" in a wide range of ratios of EO and PO units and molecular weights. It should be noted that today in the Russian Federation, industrial batches of the solubilizer Emuxol 268, which is close in its properties to the well-known poloxamer 188, are still produced, and block copolymers with other ratios of EO and PO units are synthesized to order. Conclusion . According to the retrospective analysis, the modern Russian industry has enough experience and resources to establish the synthesis of PEO and PPO block copolymers necessary to produce drugs and to develop innovative delivery systems and drugs. Based on the materials of the systematic review, the most complete register of known brands of PEO and PPO block copolymers synthesized over the past 50 years in our country and in the world was compiled for the first time, with a detailed description of their physicochemical properties.

Recently, ribavirin has demonstrated effectiveness in treating glioblastoma through intranasal administration utilizing the nose-to-brain delivery route. Enhancing ribavirin’s bioavailability can be achieved by utilizing intranasal stimuli-responsive systems that create a gel on the nasal mucosa. The research examined thermosensitive, pH-sensitive, and ion-selective polymers in various combinations and concentrations, chosen in line with the current Quality by Design (QbD) approach in pharmaceutical development. Following a thorough assessment of key parameters, the optimal composition of gellan gum at 0.5%, Poloxamer 124 at 2%, and purified water with ribavirin concentration at 100 mg/mL was formulated and subjected to in vivo testing. Through experiments on male rats, the nose-to-brain penetration mechanism of the active pharmaceutical ingredient (API) was elucidated, showcasing drug accumulation in the olfactory bulbs and brain.

In the perspective of the pharmaceutical industry development, manufacturers expand their product portfolios by updating generic drugs. Complex Generics (CG) or Nonbiological Generic Drugs (NBGD) contain known pharmaceutical substances are out of patent protection and are made by using new technologies, excipients, nanocarriers, dosage form modernization, etc. These drugs are developed in the patients’ interests to improve their life quality and increase drugs’ efficacy and safety. The article discusses the categories and characteristics of CG, shows examples available on the pharmaceutical market, API and dosage forms. This article discusses approaches to quality control that pose challenges for developers and regulators. The fundamental importance of the innovative drugs manufacturing process and the ingredients standardization in the dosage forms formulations to create the standard product are indicated. First, a comprehensive control of polymers is required as an important tool to make the necessary pharmacokinetics. The influence degree on the API release and the effectiveness of dosage form (DF) depends on the polymer’s physicochemical characteristics. In this regard, it is important to create databases of these excipients accessible to developers containing information about properties, use, dosages and safety. In view of the complexity structure and manufacturing processes of the NBGD and insufficiency of pharmacopeial requirements for standard approaches for resolving issues of comparability and bioequivalence the current regulatory documents should be expanded and revise for a correct quality assessment. There is a need to create new scientific and regulatory roadmaps for the development and approval of complex generic drugs.

INTRODUCTION:The review presents the latest developments in the area of intranasal in situ delivery systems of immunobiological drugs (IBDs). Interest in intranasal administration for IBDs has increased significantly due to the COVID-19 pandemic. However, not only intranasal delivery of vaccines is developing, but also bacteriophages, interferons, etc. In situ systems that make a selective phase transition can be a modern solution to intranasal delivery problems caused by mucociliary clearance. In addition, smart-polymers used as the main excipients in in situ systems can be used as specific adjuvants. METHODS:A scientific search was conducted on the PubMed database of medical publications for the period from 2000 to 2022, using the keywords "intranasal in situ vaccine"; "intranasal in situ immunization". There were analyzed in detail more than 70 scientific studies on intranasal in situ delivery of IBDs. RESULTS AND CONCLUSIONS:Despite the large number of new studies, the potential of possibilities of intranasal in situ systems is not being realized. Based on the results of the literature review an algorithm was created for the development of in situ systems for intranasal delivery of IBDs. Such algorithms and the methods of study design organization described in the review will help to facilitate the R&D process and bring the drug to commercial market, which will help to improve the quality of medical care.

Spray film-forming systems (SFFSs) provide great potential for the treatment of various types of wounds. Such systems afford to prolong the action of active substances, to prevent cross-contamination, and to ensure accelerated wound healing. Spray films are known since the mid-20th century, and nowadays they are widely used to treat minor skin injuries, but numerous clinical cases describe their successful use in the treatment of burns, wounds, bedsores, etc. The current level of polymer development and composite synthesis has greatly expanded the possibilities of creating compositions of spray film-forming systems. Scattered information and lack of standardization of such delivery systems creates difficulties for pharmaceutical development. This review highlights most of the existing requirements and suggestions from studies to standardize the characteristics of SFFSs and classify them based on scientific sources and regulatory documentation, as well as the position of such systems in the pharmaceutical market. The search and evaluation of known characterization methods and their modifications, as well as the approval of their list (separately for development and for standardization) can potentially increase the research interest in the problem of spray film-forming systems development and contribute to the registration of new drugs and medical devices in this promising dosage form, including with its own pharmacological effect.

None of the methods currently proposed for studying various adhesion characteristics of polymers and approved for use in dosage form formulations is standardized and recommended by regulations. The aim of the present work was to develop and test a modified method for determining mucoadhesion on a coaxial rotational viscometer using a pool of samples with known mucoadhesive properties (xanthan gum, cross-linked acrylic polymers, and various cellulose derivatives in similar concentrations). The prospects of using a rheological method for estimating the mucoadhesion of polymer solutions were demonstrated. A general visual assessment of the rheograms, i.e., the shape, smoothness, peaks, plateau zone, and shear-stress range, could be used for screening even in the absence of generally accepted optimal shear-stress values.

Objective: To develop a stable composition with the substance of PEGylated interferon alfa-2b, to study technological and biopharmaceutical characteristics of the dosage form, and to conduct preclinical studies on the chronic toxicity and local irritating effect. Methods: Solid fats Witepsol® H15, Witepsol® W 35, Suppocire® BS2X, and Suppocire® BM brands were used as the suppository bases. Polysorbate 80 was used as an emulsifier. Citric acid, ascorbic acid, sodium tetraborate, lactic acid, ethylenediaminetetetraacetic acid, tocopherol acetate was also introduced into the experimental samples. Fourteen experimental samples were screened for biological and technological indicators. Preclinical studies were performed for the optimal composition on the indicators of chronic toxicity and local irritant effect. Results: The study examined the cytotoxic effects on the Vero cell line of selected suppository bases and excipients, namely, pH regulators and antioxidants. With excipients that did not have cytotoxicity we obtained suppository compositions with the following quality indicators: cytotoxicity, specific activity of interferon, time of complete deformation of suppositories and their melting temperature. A total of 14 compositions were studied, of which 5 were selected on the basis of the results for the study of stability. Only one composition turned out to be stable for the time studied. Conclusion: The most stable in terms of “specific activity” was sample 7, its composition: Witepsol® H15/W35 70/30, polysorbate-80 0.15%, ethylenediaminetetraacetic acid (EDTA) 0.15%, sodium tetraborate 0.15%, tocopherol acetate 3.0%. Preclinical studies, that showed the absence of chronic toxicity and local irritant effect, were performed for this composition.

Thermosensitive systems based on poloxamer 407 are widely used in targeted drug delivery; however, the stability of the phase transition temperature remains insufficiently studied. This article presents the results of a study on the effect of adding polyethylene glycols (PEG) with different molecular weights and some classical gel-forming polymers on the gelation temperature of thermoreversible compositions based on poloxamer 407 in a long-term experiment. The study showed a positive effect of PEG addition with average molecular weights at concentrations of 1.5-2.0%, as well as gelling agents at a concentration below the critical gelation concentration. The proposed rheological test for studying the samples' adhesion can give an indirect forecast of the composition adhesive rate. Based on the conducted studies, three experimental binary systems based on poloxamer 407 were selected, with the addition of HPMC 0.5%, sodium alginate 0.5%, and PEG 1500 1.5%. These systems are the most promising for the further development of in situ targeted drug delivery systems.

Introduction. Periprosthetic infections are a major problem in orthopedic surgery. The most optimal way to influence the bacterial film is to suppress the early stages of its formation. The use of hydrogel coatings for the prevention of periprosthetic infections is an effective measure, while the process of coating the implant can be simplified due to the use of in situ systems.Aim. The purpose of the research is to develop and study antibacterial in situ coatings for preoperative treatment of implants.Materials and methods. In the experiment we used poloxamers Kolliphor® P 407 and Kolliphor® P 188 (BASF, Germany), hyaluronic acid high-molecular PrincipHYAL® (1400–1800 kDa), low-molecular PrincipHYAL® (400–600 kDa), mixture of high, medium and low-molecular acids PrincipHYAL® Cube3 (ROELMI HPC Srl, Italy). As screening methods for identifying the optimal composition, we used gelation temperature measurements, pH measurements, studies of rheological properties, and microbiological tests.Results and discussion. During the experiment, we found the optimal concentration of hyaluronic acid 1400–1800 kDa – 0.5 %, at which the studied composition at a temperature of 4.5 ± 0.5 °C was a homogeneous liquid, and it made a sol-gel transition when heated. It was revealed that hyaluronic acid had no significant effect on the gelling temperature, so we added poloxamer 188. We also established the influence of the hyaluronic acid molecular weight on the in situ systems characteristics. High molecular weight hyaluronic acid stabilized the viscosity values and improved the adhesive properties of the system, samples with medium and low molecular weight hyaluronic acid showed lower dynamic viscosity values at the phase gel-sol transition end. We tested the optimal composition (containing 18.0 % poloxamer 407, 2 % poloxamer 188, and 0.5 % hyaluronic acid (1400–1800 kDa) adhesion to the titanium plate. When exposed to the paddle stirrer (rotation speed 20 rpm) for 15 minutes and stored in the thermostat (37,0 ± 0,5 °C) for a week, the analyzed composition showed adhesion strength, which makes it possible to use it for coating.Conclusion. By multistage screening a sample was selected for introduction of a model antibacterial component representing a cocktail of bacteriophages Klebsiella pneumonia, Staphylococcus aureus, Escherichia coli. Microbiological studies showed good compatibility of the immunobiological substance with excipients, which indicated the prospects for further preclinical studies.

Introduction. One of the most common bacterial infections includes acute and chronic tonsillitis, affecting 10 to 15 % of adults and approximately 20–25 % of children worldwide, according to the World Health Organization. The focus of this study was an original substance, sangviritrin, containing no less than 96.5 % of the sum of bisulfates of two alkaloids: sanguinarine and chelerythrine. Given the high antimicrobial activity of sangviritrin, the research aimed to develop a local delivery system based on this medicinal substance.Aim. The aim of this work was to develop an oral medicinal form of sangviritrin.Materials and Methods. Sangviritrin, produced by the All-Russian Scientific Research Institute of Medicinal and Aromatic Plants, was used as the active pharmaceutical ingredient. The selection of auxiliary components was carried out in accordance with the methodologies specified in the State Pharmacopoeia XV edition. The organoleptic properties of the substance and spray samples were studied using A. I. Tenzova's method. The local irritant action of the spray was assessed using the conjunctival test method on chinchilla rabbits weighing 3.5–4.3 kg. Quantitative determination of sangviritrin in the medicinal form was performed using spectrophotometric methods at a wavelength of 321 ± 2 nm on a spectrophotometer SPECORD® 200 PLUS (Analytik Jena GmbH+Co. KG, Germany).Results and Discussion. Optimal auxiliary component compositions were selected based on measurements of spray technological parameters. A comprehensive approach was justified for correcting the organoleptic properties of the substance, involving the introduction of a minimal amount of sweeteners and additional use of β-cyclodextrin. Examination of the local irritant action indicated a "weak or absent" degree of local irritation.Conclusion. A local delivery system for sangviritrin has been developed for the treatment of infectious and inflammatory diseases of the oral cavity.

Introduction. Degenerative retinal diseases, including glaucoma, are the main cause of vision loss in the adult population. The development and improvement of drug treatment of this group of diseases is an urgent problem. Aim. Study of a new dosage form of methylethylpyridinol in the form of an ophthalmic gel. Materials and methods. The objects of the study were samples of eye gels containing methylethylpyridinol, for which mucoadhesion was studied by a combination of in vitro / ex vivo methods. Biodegradation and release kinetics of the active substance from the dosage form were studied using a dissolution tester in an artificial tear fluid medium. The shelf life of the dosage form was established in accordance with the stability study program. Determination of the local irritative action was carried out by conjunctival test in 10 rabbits of chinchilla breed weighing 3,6–4,1 kg. Results and discussion. The article presents the results of the study of biopharmaceutical characteristics of the previously developed ophthalmic gel of methylpyridinol based on a nonionic polymer – hydroxyethylcellulose brand Natrosol™ 250 HHX. A comparative study of mucoadhesion by in vitro / ex vivo flow of ophthalmic gel samples in the range of hydroxyethylcellulose concentration in the gel of 1–1.5 % was performed. The sample with 1.5 % polymer content had the best adhesive characteristics because it had a minimum flow rate: in vitro 2.7 · 10 6 m/s and ex vivo 2.3 · 10 6 m/s. Dissolution kinetics and visual biodegradation of the sample after "Dissolution" test were studied, which indicates prolonged release of methyl ethyl pyridinol from the gel. The stability of the developed dosage form under long-term and stress conditions was shown. The local irritating effect was estimated by the conjunctival test. Conclusion. The main biopharmaceutical characteristics of the developed ophthalmic gel methylpyridinol were determined and it was shown that it can be used as a delivery system for the treatment of degenerative retinal diseases because it possesses marked bioadhesive properties and prolonged release. The shelf life of the dosage form was determined, which was 2 years. Stress studies of methylethylpyridinol gel were carried out. The developed ophthalmic gel has no local irritating effect.