Aerosolized liposomal amphotericin B: Prediction of lung deposition, in vitro uptake and cytotoxicity

A comprehensive review on lipid nanocarrier systems for cancer treatment: fabrication, future prospects and clinical trials

Over the last few decades, cancer has been considered a clinical challenge, being among the leading causes of mortality all over the world. Although many treatment approaches have been developed for cancer, chemotherapy is still the most utilized in the clinical setting. However, the available chemotherapeutics-based treatments have several caveats including their lack of specificity, adverse effects as well as cancer relapse and metastasis which mainly explains the low survival rate of patients. Lipid nanoparticles (LNPs) have been utilized as promising nanocarrier systems for chemotherapeutics to overcome the challenges of the currently applied therapeutic strategies for cancer treatment. Loading chemotherapeutic agent(s) into LNPs improves drug delivery at different aspects including specific targeting of tumours, and enhancing the bioavailability of drugs at the tumour site through selective release of their payload, thus reducing their undesired side effects on healthy cells. This review article delineates an overview of the clinical challenges in many cancer treatments as well as depicts the role of LNPs in achieving optimal therapeutic outcomes. Moreover, the review contains a comprehensive description of the many LNPs categories used as nanocarriers in cancer treatment to date, as well as the potential of LNPs for future applications in other areas of medicine and research.

Antifungal prophylaxis with nebulized amphotericin-B in solid-organ transplant recipients with severe COVID-19: a retrospective observational study

COVID-19-associated pulmonary aspergillosis (CAPA) has emerged as a frequent complication in the intensive care unit (ICU). However, little is known about this life-threatening fungal superinfection in solid organ transplant recipients (SOTRs), including whether targeted anti-mold prophylaxis might be justified in this immunosuppressed population. We performed a multicentric observational retrospective study of all consecutive ICU-admitted COVID-19 SOTRs between August 1, 2020 and December 31, 2021. SOTRs receiving antifungal prophylaxis with nebulized amphotericin-B were compared with those without prophylaxis. CAPA was defined according the ECMM/ISHAM criteria. Sixty-four SOTRs were admitted to ICU for COVID-19 during the study period. One patient received antifungal prophylaxis with isavuconazole and was excluded from the analysis. Of the remaining 63 SOTRs, nineteen (30.2%) received anti-mold prophylaxis with nebulized amphotericin-B. Ten SOTRs who did not receive prophylaxis developed pulmonary mold infections (nine CAPA and one mucormycosis) compared with one who received nebulized amphotericin-B (22.7% vs 5.3%; risk ratio 0.23; 95%CI 0.032-1.68), but with no differences in survival. No severe adverse events related to nebulized amphotericin-B were recorded. SOTRs admitted to ICU with COVID-19 are at high risk for CAPA. However, nebulized amphotericin-B is safe and might reduce the incidence of CAPA in this high-risk population. A randomized clinical trial to confirm these findings is warranted.

Inhaled Antifungal Agents for Treatment and Prophylaxis of Bronchopulmonary Invasive Mold Infections

Pulmonary mold infections are life-threatening diseases with high morbi-mortalities. Treatment is based on systemic antifungal agents belonging to the families of polyenes (amphotericin B) and triazoles. Despite this treatment, mortality remains high and the doses of systemic antifungals cannot be increased as they often lead to toxicity. The pulmonary aerosolization of antifungal agents can theoretically increase their concentration at the infectious site, which could improve their efficacy while limiting their systemic exposure and toxicity. However, clinical experience is poor and thus inhaled agent utilization remains unclear in term of indications, drugs, and devices. This comprehensive literature review aims to describe the pharmacokinetic behavior and the efficacy of inhaled antifungal drugs as prophylaxes and curative treatments both in animal models and humans.

Conventional Antifungals for Invasive Infections Delivered by Unconventional Methods; Aerosols, Irrigants, Directed Injections and Impregnated Cement

The administration of approved antifungals via unapproved formulations or administration routes (such as aerosol, direct injection, irrigation, topical formulation and antifungal-impregnated orthopedic beads or cement) may be resorted to in an attempt to optimize drug exposure while minimizing toxicities and/or drug interactions associated with conventional (systemic) administrations. Existing data regarding such administrations are mostly restricted to uncontrolled case reports of patients with diseases refractory to conventional therapies. Attribution of efficacy and tolerability is most often problematic. This review updates prior published summaries, reflecting the most recent data and its application by available prevention and treatment guidelines for invasive fungal infections. Of the various dosage forms and antifungals, perhaps none is more widely reported than the application of amphotericin B-containing aerosols for the prevention of invasive mold infections (notably Aspergillus spp.).

New repurposed rolapitant in nanovesicular systems for lung cancer treatment: Development, in-vitro assessment and in-vivo biodistribution study

Lung cancer is characterized by poor prognosis, and is considered a serious disease that causes a significant mortality. The available conventional chemotherapeutic agents suffer from several limitations; hence, new drug molecules are constantly being sought. In the current study, lipid nanovesicles (LNVs) were selected as a colloidal vehicle for encapsulation of the FDA-approved drug; rolapitant (RP), which is used particularly for the treatment of nausea and vomiting, but is repurposed for the treatment of lung cancer in the current work. RP was loaded into various LNVs (liposomes, ethosomes and transethosomes) using the thin film hydration method, and the LNVs were evaluated for particle size, zeta potential, entrapment efficiency (EE%), storage stability and surface morphology. Besides, the in-vitro drug release, in-vitro cytotoxicity on A549 lung cancer cells, nebulization performance using next generation impactor (NGI), and the in-vivo biodistribution behaviour were evaluated. The selected ethosomal and transethosomal vesicles displayed a particle size less than 400 nm, a positive charge, and EE% exceeding 90% for RP, with a sustained release pattern over 15 days. The in-vivo biodistribution results proved the high lung deposition potential of RP-LNVs with a considerable safety. Besides, the developed RP-LNVs were able to reach the metastatic organs of lung cancer, hence they were proven promising as a possible treatment modality for lung cancer.

Conventional and hybrid nanoparticulate systems for the treatment of hepatocellular carcinoma: An updated review

Hepatocellular carcinoma (HCC) is considered a serious malignancy which affects a large number of people worldwide. Despite the presence of some diagnostic techniques for HCC, the fact that its symptoms somehow overlap with other diseases causes it to be diagnosed at a late stage, hence negatively affecting the prognosis of the disease. The currently available treatment strategies have many shortcomings such as high cost, induction of serious side effects as well as multiple drug resistance, hence resulting in therapeutic failure. Accordingly, nanoformulations have been developed in order to overcome the clinical challenges, enhance the therapeutic efficacy, and elicit chemotherapy tailor-ability. Hybrid nanoparticulate carriers in particular, which are composed of two or more drug vehicles with different physicochemical characteristics combined together in one system, have been recently reported to advance nanotechnology-based therapies. Therefore, this review sheds the light on HCC, and the role of nanotechnology and hybrid nanoparticulate carriers as well as the latest developments in the use of conventional nanoparticles in combating this disease.

Pulmonary biofilm-based chronic infections and inhaled treatment strategies

Certain pulmonary diseases, such as cystic fibrosis (CF), non-CF bronchiectasis, chronic obstructive pulmonary disease, and ventilator-associated pneumonia, are usually accompanied by respiratory tract infections due to the physiological alteration of the lung immunological defenses. Recurrent infections may lead to chronic infection through the formation of biofilms. Chronic biofilm-based infections are challenging to treat using antimicrobial agents. Therefore, effective ways to eradicate biofilms and thus relieve respiratory tract infection require the development of efficacious agents for biofilm destruction, the design of delivery carriers with biofilm-targeting and/or penetrating abilities for these agents, and the direct delivery of them into the lung. This review provides an in-depth description of biofilm-based infections caused by pulmonary diseases and focuses on current existing agents that are administered by inhalation into the lung to treat biofilm, which include i) inhalable antimicrobial agents and their combinations, ii) non-antimicrobial adjuvants such as matrix-targeting enzymes, mannitol, glutathione, cyclosporin A, and iii) liposomal formulations of anti-biofilm agents. Finally, novel agents that have shown promise against pulmonary biofilms as well as traditional and new devices for pulmonary delivery of anti-biofilm agents into the lung are also discussed.

A Critical Review on Emerging Trends in Dry Powder Inhaler Formulation for the Treatment of Pulmonary Aspergillosis

Pulmonary aspergillosis (PA), a pulmonary fungal infection caused by Aspergillus spp., is a concern for immunocompromised populations. Despite substantial research efforts, conventional treatments of PA using antifungal agents are associated with limitations such as excessive systemic exposure, serious side effects and limited availability of the therapeutics in the lungs for an adequate duration. To overcome the limitations associated with the conventional regimens, pulmonary delivery of antifungal agents has become a focal point of research because of the superiority of local and targeted drug delivery. Dry powder inhalers and nebulized formulations of antifungal agents have been developed and evaluated for their capability to effectively deliver antifungal agents to the lungs. Moreover, progress in nanotechnology and the utilization of nanocarriers in the development of pulmonary delivery formulations has allowed further augmentation of treatment capability and efficiency. Thus, the following review provides an insight into the advantages and therapeutic potential of the utilization of nanocarriers in pulmonary delivery of antifungal agents for the treatment of PA. In addition, discussions on formulation aspects and safety concerns together with the clinical and regulatory aspects of the formulations are presented, which suggest the possibility and desirability of utilization of nanocarriers in the treatment of PA.

A Facile and Novel Approach to Manufacture Paclitaxel-Loaded Proliposome Tablet Formulations of Micro or Nano Vesicles for Nebulization

Purpose

The aim of this study was to develop novel paclitaxel-loaded proliposome tablet formulations for pulmonary drug delivery.

Method

Proliposome powder formulations (i.e. F1 – F27) were prepared employing Lactose monohydrate (LMH), Microcrystalline cellulose (MCC) or Starch as a carbohydrate carriers and Soya phosphatidylcholine (SPC), Hydrogenated soya phosphatidylcholine (HSPC) or Dimyristoly phosphatidylcholine (DMPC) as a phospholipid. Proliposome powder formulations were prepared in 1:5, 1:15 or 1:25 w/w lipid phase to carrier ratio (lipid phase; comprising of phospholipid and cholesterol in 1:1 M ratio) and Paclitaxel (PTX) was used as model anticancer drug.

Results

Based on flowability studies, out of 27 formulations; F3, F6, and F9 formulations were selected as they exhibited an excellent angle of repose (AOR) (17.24 ± 0.43, 16.41 ± 0.52 and 15.16 ± 0.72°), comparatively lower size of vesicles (i.e. 5.35 ± 0.76, 6.27 ± 0.59 and 5.43 ± 0.68 μm) and good compressibility index (14.81 ± 0.36, 15.01 ± 0.35 and 14.56 ± 0.14) via Carr’s index. The selected formulations were reduced into Nano (N) vesicles via probe sonication, followed by spray drying (SD) to get a dry powder of these formulations as F3SDN, F6SDN and F9SDN, and gave high yield (>53%) and exhibited poor to very poor compressibility index values via Carr’s Index. Post tablet manufacturing, F3 tablets formulation showed uniform weight uniformity (129.40 ± 3.85 mg), good crushing strength (14.08 ± 1.95 N), precise tablet thickness (2.33 ± 0.51 mm) and a short disintegration time of 14.35 ± 0.56 min, passing all quality control tests in accordance with British Pharmacopeia (BP). Upon nebulization of F3 tablets formulation, Ultrasonic nebulizer showed better nebulization time (8.75 ± 0.86 min) and high output rate (421.06 ± 7.19 mg/min) when compared to Vibrating mesh nebulizer. PTX-loaded F3 tablet formulations were identified as toxic (60% cell viability) to cancer MRC-5 SV2 cell lines while safe to normal MRC-5 cell lines.

Conclusion

Overall, in this study LMH was identified as a superior carbohydrate carrier for proliposome tablet manufacturing in a 1:25 w/w lipid to carrier ratio for in-vitro nebulization via Ultrasonic nebulizer.

Electronic supplementary material

The online version of this article (10.1007/s11095-020-02840-w) contains supplementary material, which is available to authorized users.

Potential application of liposomal nanodevices for non-cancer diseases: an update on design, characterization and biopharmaceutical evaluation

Liposomes, lipid-based vesicular systems, have attracted major interest as a means to improve drug delivery to various organs and tissues in the human body. Recent literature highlights the benefits of liposomes for use as drug delivery systems, including encapsulating of both hydrophobic and hydrophilic cargos, passive and active targeting, enhanced drug bioavailability and therapeutic effects, reduced systemic side effects, improved cargo penetration into the target tissue and triggered contents release. Pioneering work of liposomes researchers led to introduction of long-circulating, ligand-targeted and triggered release liposomes, as well as, liposomes containing nucleic acids and vesicles containing combination of cargos. Altogether, these findings have led to widespread application of liposomes in a plethora of areas from cancer to conditions such as cardiovascular, neurologic, respiratory, skin, autoimmune and eye disorders. There are numerous review articles on the application of liposomes in treatment of cancer, which seems the primary focus, whereas other diseases also benefit from liposome-mediated treatments. Therefore, this article provides an illustrated detailed overview of liposomal formulations, in vitro characterization and their applications in different disorders other than cancer. Challenges and future directions, which must be considered to obtain the most benefit from applications of liposomes in these disorders, are discussed.

Assessment of the mutagenic, recombinogenic, and carcinogenic potential of amphotericin B in somatic cells of Drosophila melanogaster

Amphotericin B (AmB) is an antifungal antibiotic extracted from Streptomyces nodosus. Its fungicidal activity depends primarily on its binding to the sterol group that is present in fungal membranes. In view of the toxicity of this drug, the purpose of this study was to evaluate its mutagenic, carcinogenic, and recombinogenic activity, based on the wing somatic mutation and recombination test (SMART) and the epithelial tumor detection test (wts) applied to Drosophila melanogaster. Larvae were chronically treated with different concentrations of AmB (0.01, 0.02, and 0.04 mg/mL). The results revealed that AmB is a promutagen exhibiting increase in the number of spots on individuals from high bioactivation (HB) cross with a high level of cytochrome P450. The results also indicate that the main genotoxic event induced by AmB is recombinogenicity. Homologous recombination can act as a determinant at different stages of carcinogenesis. For verification of carcinogenic potential of this compound, larvae from the wts/mwh and wts/ORR, flr³ were treated with the same three AmB concentrations used in the SMART assay. The results did not provide evidence that AmB has carcinogenic potential in wts/mwh individuals. However, individuals from wts/ORR, flr³ developed tumors at the highest concentration tested.

Fundamentals of aerosol therapy in critical care

Drug dosing in critically ill patients is challenging due to the altered drug pharmacokinetics–pharmacodynamics associated with systemic therapies. For many drug therapies, there is potential to use the respiratory system as an alternative route for drug delivery. Aerosol drug delivery can provide many advantages over conventional therapy. Given that respiratory diseases are the commonest causes of critical illness, use of aerosol therapy to provide high local drug concentrations with minimal systemic side effects makes this route an attractive option. To date, limited evidence has restricted its wider application. The efficacy of aerosol drug therapy depends on drug-related factors (particle size, molecular weight), device factors, patient-related factors (airway anatomy, inhalation patterns) and mechanical ventilation-related factors (humidification, airway). This review identifies the relevant factors which require attention for optimization of aerosol drug delivery that can achieve better drug concentrations at the target sites and potentially improve clinical outcomes.

Inhaled formulations and pulmonary drug delivery systems for respiratory infections

Respiratory infections represent a major global health problem. They are often treated by parenteral administrations of antimicrobials. Unfortunately, systemic therapies of high-dose antimicrobials can lead to severe adverse effects and this calls for a need to develop inhaled formulations that enable targeted drug delivery to the airways with minimal systemic drug exposure. Recent technological advances facilitate the development of inhaled anti-microbial therapies. The newer mesh nebulisers have achieved minimal drug residue, higher aerosolisation efficiencies and rapid administration compared to traditional jet nebulisers. Novel particle engineering and intelligent device design also make dry powder inhalers appealing for the delivery of high-dose antibiotics. In view of the fact that no new antibiotic entities against multi-drug resistant bacteria have come close to commercialisation, advanced formulation strategies are in high demand for combating respiratory 'super bugs'.

Safety and efficacy of amphotericin-B deoxycholate inhalation in critically ill patients with respiratory Candida spp. colonization: a retrospective analysis

Background

Candida spp. are frequently cultured from the respiratory tract in critically ill patients. Most intensivists start amphotericin-B deoxycholate (ABDC) inhalation therapy to eradicate Candida spp. from the respiratory tract. However, the safety and efficacy of this treatment are not well established. The purpose of this study was to assess the safety and efficacy of ABDC inhalation for the treatment of respiratory Candida spp. colonization in critically ill patients.

Methods

All non-neutropenic patients admitted into the intensive care unit (ICU) of a university hospital from December 2010–2011, who had positive Candida spp. cultures of the respiratory tract for more than 1 day and required mechanical ventilation >48 h were retrospectively included. The decision to start ABDC inhalation had been made by attending intensivists on clinical grounds in the context of selective decontamination of the digestive tract. Infection characteristics and patient courses were assessed.

Results

Hundred and thirteen consecutive patients were studied. Fifty-one of them received ABDC inhalation and their characteristics at baseline and day 1 of respiratory colonization did not differ from those of colonized patients not receiving treatment (n = 62). The ABDC-treated group had a similar Candida spp. load but did not decolonize more rapidly as compared to untreated patients. The clinical pulmonary infection and lung injury scores did not decrease as in the untreated group. In a Cox proportional hazard model, the duration of mechanical ventilation was increased (P < 0.003) by ABDC treatment independently of other potential determinants and Candida spp. colonization. No differences in ventilator-associated pneumonia or in overall mortality (up to day 90) were observed.

Conclusion

Treatment of respiratory Candida spp. colonization in non-neutropenic critically ill patients by inhaled ABDC may not affect respiratory colonization but may increase duration of mechanical ventilation, because of direct toxicity of the drug on the lung.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-014-0575-3) contains supplementary material, which is available to authorized users.