Solid Nanomedicines of Nifurtimox and Benznidazole for the Oral Treatment of Chagas Disease

Redefining the treatment of Chagas disease: a review of recent clinical and pharmacological data for a novel formulation of nifurtimox

Nifurtimox has been used for over 50 years to treat patients with Chagas disease, a potentially life-threatening neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. Without effective antitrypanosomal treatment, the infection can persist and progress to a chronic, often debilitating, clinical form. Migration and urbanization, as well as the shifting distribution of the parasite's insect vector, have contributed to the emergence of Chagas disease as a global health threat. Administration of nifurtimox involves adjusting the dose for age and body weight. Particularly for children, this often requires the previously available 120 mg tablet to be divided manually, which could be problematic. To address this challenge, a new formulation tablet of nifurtimox was developed. Available in two dose strengths, 30 mg and 120 mg, the new formulation tablets contain a functional score line to facilitate accurate division. In addition, the formulation now allows rapid and easy dispersion in water to form a slurry for use by patients with difficulty swallowing tablets. These features enable more accurate body-weight-based and age-appropriate dosing and administration, which should prove beneficial for younger patients, including newborns and babies with a body weight ≥2.5 kg. Development of the new formulation nifurtimox tablets was guided by substantially updating pharmacological and clinical knowledge of the drug to meet current standards and regulatory requirements. This was achieved by conducting a substantial array of additional non-clinical and clinical studies to better understand and characterize clinically relevant aspects of nifurtimox pharmacokinetics. The efficacy and safety of the new tablet in children with Chagas disease was subsequently demonstrated in a large prospective randomized clinical trial with prolonged follow-up. In the present paper, we review key findings that contributed to the successful clinical development of the new formulation nifurtimox tablet, the availability of which redefines the treatment of young patients with Chagas disease.

3D-Printed Tablets of Nifurtimox: In Vitro and In Vivo Anti-Trypanosoma cruzi Studies

Background/Objectives: Chagas disease is a neglected tropical disease caused by infection with the parasite Trypanosoma cruzi. Benznidazole and nifurtimox are the only approved drugs for treating this condition, but their low aqueous solubility may lead to erratic bioavailability. This work aimed for the first time to formulate tablets of nifurtimox by hot melt extrusion coupled with 3D printing as a strategy to increase drug dissolution and the production of tablets with dosage on demand. Methods: Different pharmaceutical-grade polymers were evaluated through film casting, and those with promising nifurtimox amorphization capacity were further used to prepare filaments by hot melt extrusion. The printability of the obtained filaments was tested, and the polyvinyl alcohol filament was further used for printing tablets containing 120 and 60 mg of nifurtimox. Results: Three-dimensional tablets showed a remarkable improvement in the drug dissolution rate compared to commercial tablets and a dissolution efficiency 2.8 times higher. In vivo studies were carried out on Swiss mice. Parasitemia curves of nifurtimox printed tablets were significantly superior to the pure drug. Moreover, NFX 3D tablets provided a similar Trypanosoma cruzi reduction in plasmatic concentration to benznidazole, the gold-standard drug for acute-phase treatment of the Chagas disease. Conclusions: The findings of this work showed that hot melt extrusion coupled with 3D printing is a promising alternative for increasing nifurtimox biopharmaceutical properties and an attractive approach for personalized medicine.

Innovative technologies to address neglected tropical diseases in African settings with persistent sociopolitical instability

The health, economic, and social burden of neglected tropical diseases (NTDs) in Africa remains substantial, with elimination efforts hindered by persistent sociopolitical instability, including ongoing conflicts among political and ethnic groups that lead to internal displacement and migration. Here, we explore how innovative technologies can support Africa in addressing NTDs amidst such instability, through analysis of WHO and UNHCR data and a systematic literature review. Countries in Africa facing sociopolitical instability also bear a high burden of NTDs, with the continent ranking second globally in NTD burden (33%, 578 million people) and first in internal displacement (50%, 31.6 million people) in 2023. Studies have investigated technologies for their potential in NTD prevention, surveillance, diagnosis, treatment and management. Integrating the evidence, we discuss nine promising technologies-artificial intelligence, drones, mobile clinics, nanotechnology, telemedicine, augmented reality, advanced point-of-care diagnostics, mobile health Apps, and wearable sensors-that could enhance Africa's response to NTDs in the face of persistent sociopolitical instability. As stability returns, these technologies will evolve to support more comprehensive and sustainable health development. The global health community should facilitate deployment of health technologies to those in greatest need to help achieve the NTD 2030 Roadmap and other global health targets.

3D printed benznidazole tablets based on an interpolyelectrolyte complex by melting solidification printing process (MESO-PP): An innovative strategy for personalized treatment of Chagas disease

3D printing technology is revolutionizing pharmaceuticals, offering tailored solutions for solid dosage forms. This innovation is particularly significant for conditions like Chagas disease, which require weight-dependent treatments. In this work, a formulation of benznidazole (BNZ), the primary treatment for this infection, was developed to be utilized with the Melting Solidification Printing Process (MESO-PP) 3D printing technique. Considering the limited aqueous solubility of BNZ, an interpolyelectrolyte complex (IPEC), composed of chitosan and pectin, was integrated to improve its dissolution profile. The formulations, also called inks in this context, with and without IPEC were integrally characterized and compared. The printing process was studied, the release of BNZ from 3D-prints (3DP) was exhaustively analyzed and a physiologically based pharmacokinetic model (PKPB) was developed to forecast their pharmacokinetic performance. 3DP were successfully achieved loading 25, 50 and 100 mg of BNZ. The presence of the IPEC in the ink caused a decrease in the crystalline domain of BNZ and facilitated the printing process, reaching a print success rate of 83.3 %. Interestingly, 3DP-IPEC showed accelerated release dissolution profiles, releasing over 85 % of BNZ in 90 min, while 3DP took up to 48 h for doses above 25 mg. The PBPK model demonstrated that 3DP-IPEC tablets would present high bioavailability (0.92), higher than 3DP (0.36) and similar to the commercial product. This breakthrough holds immense potential for improving treatment outcomes for neglected diseases.

Organic solvent-free benznidazole nanosuspension as an approach to a novel pediatric formulation for Chagas disease

Aim: Benznidazole (BNZ), a class-II drug, is the primary treatment for Chagas disease, but its low aqueous solubility presents challenges in formulation and efficacy. Nanosuspensions (NS) could potentially address these issues.Methods: BNZ-NS were prepared using a simple, organic solvents-free nano-milling approach. Physicochemical characterizations were conducted on both NS and lyophilized solid-state BNZ-nanocrystals (NC).Results: BNZ-NS exhibited particle size <500 nm, an acceptable polydispersity index (0.23), high Z-potential, and physical stability for at least 90 days. BNZ-NC showed tenfold higher solubility than pure BNZ. Dissolution assays revealed rapid BNZ-NS dissolution. BNZ-NC demonstrated biocompatibility on an eukaryotic cell and enhanced BNZ efficacy against trypomastigotes of Trypanosoma cruzi.Conclusion: BNZ-NS offers a promising alternative, overcoming limitations associated with BNZ for optimized pharmacotherapy.

Nanomedicines against Chagas disease: a critical review

Chagas disease (CD) is the most important endemic parasitosis in South America and represents a great socioeconomic burden for the chronically ill and their families. The only currently available treatment against CD is based on the oral administration of benznidazole, an agent, developed in 1971, of controversial effectiveness on chronically ill patients and toxic to adults. So far, conventional pharmacological approaches have failed to offer more effective and less toxic alternatives to benznidazole. Nanomedicines reduce toxicity and increase the effectiveness of current oncological therapies. Could nanomedicines improve the treatment of the neglected CD? This question will be addressed in this review, first by critically discussing selected reports on the performance of benznidazole and other molecules formulated as nanomedicines in in vitro and in vivo CD models. Taking into consideration the developmental barriers for nanomedicines and the degree of current technical preclinical efforts, a prospect of developing nanomedicines against CD will be provided. Not surprisingly, we conclude that structurally simpler formulations with minimal production cost, such as oral nanocrystals and/or parenteral nano-immunostimulants, have the highest chances of making it to the market to treat CD. Nonetheless, substantive political and economic decisions, key to facing technological challenges, are still required regarding a realistic use of nanomedicines effective against CD.

Synthesis and biological evaluation of novel benzothiazole derivatives as potential anticancer and antiinflammatory agents

Introduction: Cancer, a significant global health concern, necessitates innovative treatments. The pivotal role of chronic inflammation in cancer development underscores the urgency for novel therapeutic strategies. Benzothiazole derivatives exhibit promise due to their distinctive structures and broad spectrum of biological effects. This study aims to explore new anti-tumor small molecule drugs that simultaneously anti-inflammatory and anticancer based on the advantages of benzothiazole frameworks. Methods: The compounds were characterized by nuclear magnetic resonance (NMR), liquid chromatograph-mass spectrometer (LC-MS) and high performance liquid chromatography (HPLC) for structure as well as purity and other related physicochemical properties. The effects of the compounds on the proliferation of human epidermoid carcinoma cell line (A431) and human non-small cell lung cancer cell lines (A549, H1299) were evaluated by MTT method. The effect of compounds on the expression levels of inflammatory factors IL-6 and TNF-α in mouse monocyte macrophages (RAW264.7) was assessed using enzyme-linked immunosorbent assay (ELISA). The effect of compounds on apoptosis and cell cycle of A431 and A549 cells was evaluated by flow cytometry. The effect of compounds on A431 and A549 cell migration was evaluated by scratch wound healing assay. The effect of compounds on protein expression levels in A431 and A549 cells was assessed by Western Blot assay. The physicochemical parameters, pharmacokinetic properties, toxicity and drug similarity of the active compound were predicted using Swiss ADME and admetSAR web servers. Results: Twenty-five novel benzothiazole compounds were designed and synthesized, with their structures confirmed through spectrogram verification. The active compound 6-chloro-N-(4-nitrobenzyl) benzo[d] thiazol-2-amine (compound B7) was screened through a series of bioactivity assessments, which significantly inhibited the proliferation of A431, A549 and H1299 cancer cells, decreased the activity of IL-6 and TNF-α, and hindered cell migration. In addition, at concentrations of 1, 2, and 4 μM, B7 exhibited apoptosis-promoting and cell cycle-arresting effects similar to those of the lead compound 7-chloro-N-(2, 6-dichlorophenyl) benzo[d] thiazole-2-amine (compound 4i). Western blot analysis confirmed that B7 inhibited both AKT and ERK signaling pathways in A431 and A549 cells. The prediction results of ADMET indicated that B7 had good drug properties. Discussion: This study has innovatively developed a series of benzothiazole derivatives, with a focus on compound B7 due to its notable dual anticancer and anti-inflammatory activities. B7 stands out for its ability to significantly reduce cancer cell proliferation in A431, A549, and H1299 cell lines and lower the levels of inflammatory cytokines IL-6 and TNF-α. These results position B7B7 as a promising candidate for dual-action cancer therapy. The study's mechanistic exploration, highlighting B7's simultaneous inhibition of the AKT and ERK pathways, offers a novel strategy for addressing both the survival mechanisms of tumor cells and the inflammatory milieu facilitating cancer progression.

Stability study and development of the validated infrared spectrometric method for quantitative analysis of sevoflurane compared with the gas chromatographic method

Sevoflurane, also called fluoromethyl ether, is an inhalation anesthetic agent used to initiate and maintain general anesthesia for adults and pediatric patients during surgical procedures. Several analytical methods have previously been applied to follow the properties and quality of sevoflurane, including mass spectrometry and gas chromatography methods. These methods are practically tedious and need sophisticated apparatus. In the present work, an attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectrometric method was used for the quantitative determination of sevoflurane which is characterized as a fast, accurate, and available technique for most pharmaceutical laboratories, besides the gas chromatographic method which is the most suitable for the detection of impurities. Sevoflurane is a liquid and it is applied directly on the glass top of the ATR-FTIR either as a concentrated solution or diluted with hexane as a diluent, which did not interfere with sample determination within the specified wavelength range of the IR spectrum, particularly the wavelength of the ethereal group at 1200 cm-1. This method can be applied to the identification test and quantitative assay of sevoflurane since it is validated for the precision, accuracy, reproducibility, and specificity in the analysis of sevoflurane as a pharmaceutical product. However, still, there is a need for a gas chromatographic method to detect the impurities and degradation products during the stability study of sevoflurane.

From Benznidazole to New Drugs: Nanotechnology Contribution in Chagas Disease

Chagas disease is a neglected tropical disease caused by the protozoan Trypanosoma cruzi. Benznidazole and nifurtimox are the two approved drugs for their treatment, but both drugs present side effects and efficacy problems, especially in the chronic phase of this disease. Therefore, new molecules have been tested with promising results aiming for strategic targeting action against T. cruzi. Several studies involve in vitro screening, but a considerable number of in vivo studies describe drug bioavailability increment, drug stability, toxicity assessment, and mainly the efficacy of new drugs and formulations. In this context, new drug delivery systems, such as nanotechnology systems, have been developed for these purposes. Some nanocarriers are able to interact with the immune system of the vertebrate host, modulating the immune response to the elimination of pathogenic microorganisms. In this overview of nanotechnology-based delivery strategies for established and new antichagasic agents, different strategies, and limitations of a wide class of nanocarriers are explored, as new perspectives in the treatment and monitoring of Chagas disease.

Formulation of benznidazole-lipid nanocapsules: Drug release, permeability, biocompatibility, and stability studies

Benznidazole, a poorly soluble in water drug, is the first-line medication for the treatment of Chagas disease, but long treatment periods at high dosages cause several adverse effects with insufficient activity in the chronic phase. According to these facts, there is a serious need for novel benznidazole formulations for improving the chemotherapy of Chagas disease. Thus, this work aimed to incorporate benznidazole into lipid nanocapsules for improving its solubility, dissolution rate in different media, and permeability. Lipid nanocapsules were prepared by the phase inversion technique and were fully characterized. Three formulations were obtained with a diameter of 30, 50, and 100 nm and monomodal size distribution with a low polydispersity index and almost neutral zeta potential. Drug encapsulation efficiency was between 83 and 92% and the drug loading was between 0.66 and 1.04%. Loaded formulations were stable under storage for one year at 4 °C. Lipid nanocapsules were found to protect benznidazole in simulated gastric fluid and provide a sustained release platform for the drug in a simulated intestinal fluid containing pancreatic enzymes. The small size and the almost neutral surface charge of these lipid nanocarriers improved their penetration through mucus and such formulations showed a reduced chemical interaction with gastric mucin glycoproteins. LNCs. The incorporation of benznidazole in lipid nanocapsules improved the drug permeability across intestinal epithelium by 10-fold compared with the non-encapsulated drug while the exposure of the cell monolayers to these nanoformulations did not affect the integrity of the epithelium.

Selected Aspects of the Analytical and Pharmaceutical Profiles of Nifurtimox

Nifurtimox is a nitroheterocyclic drug employed for treatment of trypanosomiases (Chagas disease and West African sleeping sickness); its use for certain cancers has also been assessed. Despite having been in the market for over 50 years, knowledge of nifurtimox is still fragmentary and incomplete. Relevant aspects of the chemistry and biology of nifurtimox are reviewed to summarize the current knowledge of this drug. These comprise its chemical synthesis and the preparation of some analogues, as well as its chemical degradation. Selected physical data and physicochemical properties are also listed, along with different approaches toward the analytical characterization of the drug, including electrochemical (polarography, cyclic voltammetry), spectroscopic (ultraviolet-visible, nuclear magnetic resonance, electron spin resonance), and single crystal X-ray diffractometry. The array of polarographic, ultraviolet-visible spectroscopic, and chromatographic methods available for the analytical determination of nifurtimox (in bulk drug, pharmaceutical formulations, and biological samples), are also presented and discussed, along with chiral chromatographic and electrophoretic alternatives for the separation of the enantiomers of the drug. Aspects of the drug likeliness of nifurtimox, its classification in the Biopharmaceutical Classification System, and available pharmaceutical formulations are detailed, whereas pharmacological, chemical, and biological aspects of its metabolism and disposition are discussed.

3D Printing Technologies in Personalized Medicine, Nanomedicines, and Biopharmaceuticals

3D printing technologies enable medicine customization adapted to patients' needs. There are several 3D printing techniques available, but majority of dosage forms and medical devices are printed using nozzle-based extrusion, laser-writing systems, and powder binder jetting. 3D printing has been demonstrated for a broad range of applications in development and targeting solid, semi-solid, and locally applied or implanted medicines. 3D-printed solid dosage forms allow the combination of one or more drugs within the same solid dosage form to improve patient compliance, facilitate deglutition, tailor the release profile, or fabricate new medicines for which no dosage form is available. Sustained-release 3D-printed implants, stents, and medical devices have been used mainly for joint replacement therapies, medical prostheses, and cardiovascular applications. Locally applied medicines, such as wound dressing, microneedles, and medicated contact lenses, have also been manufactured using 3D printing techniques. The challenge is to select the 3D printing technique most suitable for each application and the type of pharmaceutical ink that should be developed that possesses the required physicochemical and biological performance. The integration of biopharmaceuticals and nanotechnology-based drugs along with 3D printing ("nanoprinting") brings printed personalized nanomedicines within the most innovative perspectives for the coming years. Continuous manufacturing through the use of 3D-printed microfluidic chips facilitates their translation into clinical practice.

Drug Stability: ICH versus Accelerated Predictive Stability Studies

The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), along with the World Health Organization (WHO), has provided a set of guidelines (ICH Q1A-E, Q3A-B, Q5C, Q6A-B) intended to unify the standards for the European Union, Japan, and the United States to facilitate the mutual acceptance of stability data that are sufficient for registration by the regulatory authorities in these jurisdictions. Overall, ICH stability studies involve a drug substance tested under storage conditions and assess its thermal stability and sensitivity to moisture. The long-term testing should be performed over a minimum of 12 months at 25 °C ± 2 °C/60% RH ± 5% RH or at 30 °C ± 2 °C/65% RH ± 5% RH. The intermediate and accelerated testing should cover a minimum of 6 months at 30 °C ± 2 °C/65% RH ± 5% RH (which is not necessary if this condition was utilized as a long-term one) and 40 °C ± 2 °C/75% RH ± 5% RH, respectively. Hence, the ICH stability testing for industrially fabricated medicines is rigorous and tedious and involves a long period of time to obtain preclinical stability data. For this reason, Accelerated Predictive Stability (APS) studies, carried out over a 3-4-week period and combining extreme temperatures and RH conditions (40-90 °C)/10-90% RH, have emerged as novel approaches to predict the long-term stability of pharmaceutical products in a more efficient and less time-consuming manner. In this work, the conventional ICH stability studies versus the APS approach will be reviewed, highlighting the advantages and disadvantages of both strategies. Furthermore, a comparison of the stability requirements for the commercialization of industrially fabricated medicines versus extemporaneous compounding formulations will be discussed.