Tuberculosis is a chronic infectious disease, usually localized in the respiratory system and representing one of the most important global social and biomedical health problems associated with the spread of therapy-resistant forms (multidrug-resistant and extensively drug-resistant tuberculosis). One of the most promising targets for the development of antimycobacterial drugs is the enzyme DprE1, which is involved in the synthesis of the cell wall of mycobacteria. In the series of DprE1 inhibitor drugs, the most advanced drug is PBTZ169 (INN maсozinone). Clinical trials (CT) of the efficacy and safety of macozinone are conducted by the pharmaceutical company LLC NEARMEDIC PLUS in the Russian Federation, and in other countries (Sponsors: Innovative Medicines for Tuberculosis Foundation, cole polytechnique fdrale de Lausanne and Bill and Melinda Gates Foundation). The publication describes results of completed I, IIa and Ib phases CT, conducted in the Russian Federation. Aim. The goal of phase I CT was to assess the safety, tolerability and pharmacokinetics (PK) of PBTZ169, 40 mg capsule, after single and multiple administration under fasting conditions in increasing doses in healthy volunteers. The goal of phase IIa CT was to study the efficacy (in terms of early bactericidal activity EBA), safety and PK of the drug PBTZ169, 80 mg capsules, in various doses, when used as monotherapy in patients with newly diagnosed respiratory tuberculosis with bacterial excretion and retained sensitivity to isoniazid and rifampicin. The purpose of phase Ib CT was to evaluate the safety, tolerability, PK of PBTZ169, 80 mg capsule, after single, double and multiple administration under fasting conditions in increasing doses, as well as the effect of food on its bioavailability in healthy volunteers. Materials and methods. The data of 100 healthy volunteers and 15 patients with newly diagnosed pulmonary tuberculosis, who received the study medication PBTZ169, capsules 40 mg and 80 mg, in the dose range 40 mg 1280 mg of PBTZ169, obtained during phase I, IIa and Ib CTs were analyzed. During I phases CTs, safety, tolerability, and PK of the drug after a single and multiple administration under fasting condition and after meals at rising doses were evaluated. The safety assessment included evaluation of AE/SAE, vital signs, ECG results, and laboratory tests results in the safety population. In the course of phase IIa CT, in addition to safety, tolerance, and PK evaluation, the efficacy of the drug (in terms of EBA) using sputum culture on agar with CFU/ml counting (main method) and quantitative PCR method (auxiliary method) was evaluated. Results. During all CTs, a high safety and tolerability profile was shown, the main PK parameters of the drug and the efficacy were described. PBTZ169 demonstrated linear PK in the dosage range up to 640 mg after single and multiple administration, a statistically significant of EBA of the drug after monotherapy at the dose of 640 mg/day was demonstrate, and it was concluded that the preferred regimen of the drug PBTZ169 intake is administration after meals. Good tolerability and a favorable safety profile of the drug in the studied doses range were demonstrate during all the CTs. Conclusion. One of the most promising and currently studied drugs-inhibitors of DprE1, a new target for the cell wall of mycobacteria, is PBTZ169 or macozinone, which is being develop by the Russian pharmaceutical company NEARMEDIC PLUS ltd.

Macozinone (MCZ) is the newest first-in-class clinical-stage benzothiazinone-based drug candidate for the treatment of tuberculosis. Yet, the extremely low oral bioavailability of MCZ, a major problem in clinical trials, needed to be addressed, and we are pleased to present our attempts to solve this issue.

Kagocel is a synthetic carboxymethylcellulose derivative copolymerized with gossypol. Clinical data evidence its safety and efficiency for the treatment of flu and other viral infections via enhancement of interferon production. The gut-associated lymphoid tissue seems a likely site of kagocel action. The study was aimed to investigate the molecular mechanisms of its action using murine Peyer’s patches lymphocytes as a test system and the cytokines production and gene expression patterns as the primary outcomes. The Peyer’s patches lymphocytes isolated from BALB/c mice were stimulated with concanavalin A, or, to mimic viral infection, with a combination of concanavalin A and TLR3 ligand poly I:C. After 24 h of stimulation the cells were treated with saline, 30, 100, or 300 μg/ml of kagocel, or, as positive controls, 300 μg/ml oats b-D-glucan or 300 μg/ml lentinan. After 24 and 72 h of incubation with these drugs cytokines production was analyzed with ELISA and gene expression pattern was investigated using nCounter Inflammation panel chips followed by bioinformatics analysis. Expression of genes involved in the inflammatory response, antiviral defense, lymphocytes survival and proliferation (C1qa, C2, C3, Ccl21a, Il11, Il1b, Il23a, Il5, Ltb4r2, Alox15, Pla2g4a, Ptger1, Mapkapk5, Hras, Ifna1, Tlr2, Mrc1, Mx2) was upregulated in kagocel-treated Peyer’s patches lymphocytes. A list of plausible transcription factors (CEBPs, IRF, NFκB, RXR, Stat, Tead4, and ZSCAN) and master-regulators has been identified (cIAP, CIKS, dock9, MEKK1, FXR, IKK, IRAK, TRAF, dsRNA:TLR3:TRIF). The changes in gene expression pattern and the outcomes of bioinformatics analysis suggest that pattern recognition receptors, TLRs and dectin-1, are the key mediators of kagocel immunomodulatory action, with the possible involvement of interferon autocrine loop. The genes upregulated with kagocel include diverse components of the innate immune defense system.

Introduction.Tuberculosis (TB) is one of the top ten causes of death worldwide. Improvement of the treatment options via development of new drugs and treatment regimens that would be more convenient for patients is one of key options of improving the effecacy of the TB prevention and careis. Since the creation of new treatment regimens by minimizing the number of the drugs used and reducing the duration of treatment is the most promising and correct direction, macozinone, a new candidate of the benzothiazinone series, can become the basis for development of new chemotherapy regimens for drug-resistant forms of TB including the combination of macozinone with the most effective modern anti-TB drugs. Aim.Comparative evaluation of the pharmacokinetic properties of macozinone capsules 80 mg and the new dosage form a dispersible tablet for preparation of oral solution. Materials and methods.Solubility of the substance macozinone in biorelevant media in vitro, permeability of macozinone in the test Caco-2 in vitro, as well as pharmacokinetics of macozinone in dogs in vivo were evaluated. Results.The solubility assessment in biorelevant media showed that the average limit of macozinone substance dissolution in the pH 5.0 acetate buffer solution was from 6 to 9 mg/l, in FaSSIF medium (fasted) from 2.5 to 4 mg/l, and in FeSSIF medium (after meals) from 16.8 to 29 mg/l. It is established that the cell permeability of the pharmaceutical substance macozinone in the CACO-2 test system is on average 2.510-6cm/s in the forward direction from the apical to basolateral cell membrane, and 1.510-6cm/s in the reverse direction, which corresponds to low permeability. The main pharmacokinetic parameters of macozinone dispersable tablets 160 mg, after dosing with food and on an empty stomach, as well as capsules 80 mg, when administered on an empty stomach in vivo studies in dogs are presented. Discussion.The specific physicochemical properties of macozinone, the problems of developing the new dosage form, as well as ways of solving some of them are presented. Conclusion.In the process of new dosage forms development, the existing chemical properties of the macozinone substance should be considered. One of the promising ways of increasing bioavailability and, consiquently, efficacy is development a fundamentally new drug form with modified release within the absorption window.

The aim. To analyze and summarize the available results of experimental and clinical scientific studies of synthetic analogs of leu-enkephalin; to evaluate the expansion of the spectrum of application of the original medicine based on hexapeptide succinate in patients with various diseases of different etiologies.Materials and methods. An analysis of scientific literature data in the PubMed, eLibrary.ru and CyberLeninka databases was carried out. The search depth was 50 years (from 1976 to 2024), the list of references includes 60 scientific papers.Results. It was revealed that receptors for endogenous opioid peptides are widespread in living organisms. Modern neuropharmacology recognizes 4 main types of opioid receptors: μ (MOR) — mu, δ (DOR) — delta, κ (KOR) — kappa and NOP — nociceptive receptor, which bind to endogenous opioids such as enkephalins, endorphins, endomorphins, dynorphins and nociceptin. Due to their antioxidant, immunomodulatory, and anti-inflammatory properties, analogs of opioid peptides are widely used in Russian medicine. A number of experimental and clinical studies are presented, to prove that agonists of delta-opioid receptors can “soften” organ damage in a variety of diseases accompanied by oxidative stress and endothelial dysfunction. The dose-dependent regulatory effect is realized with intravenous, intramuscular and intranasal administration. The therapeutic efficacy of leu-enkephalin analogs based on tyrosyl-D-alanyl-glycyl-phenylalanyl-leucyl-arginine is analyzed, and the prospects for using the new original Russian medicine Ambervin® Pulmo with the inclusion of succinic acid salts are also discussed.Conclusion. The information on the functional properties of leucine-enkephalin analogs presented in the article indicates broad prospects for the use of medicines based on tyrosyl-D-alanyl-glycyl-phenylalanyl-leucyl-arginine with the inclusion of succinic acid salt in the complex therapy of many diseases for the purpose of organ protection.