Inhaled dry powder cisplatin increases antitumour response to anti-PD1 in a murine lung cancer model.

Despite advances in targeted therapies and immunotherapy in lung cancer, chemotherapy remains the backbone of treatment in most patients at different stages of the disease. Inhaled chemotherapy is a promising strategy to target lung tumours and to limit the induced severe systemic toxicities. Cisplatin dry powder for inhalation (CIS-DPI) was tested as an innovative way to deliver cisplatin locally via the pulmonary route with minimal systemic toxicities. In vivo, CIS-DPI demonstrated a dose-dependent antiproliferative activity in the M109 orthotopic murine lung tumour model and upregulated the immune checkpoint PD-L1 on lung tumour cells. Combination of CIS-DPI with the immune checkpoint inhibitor anti-PD1 showed significantly reduced tumour size, increased the number of responders and prolonged median survival over time in comparison to the anti-PD1 monotherapy. Furthermore, the CIS-DPI and anti-PD1 combination induced an intra-tumour recruitment of conventional dendritic cells and tumour infiltrating lymphocytes, highlighting an anti-tumour immune response. This study demonstrates that combining CIS-DPI with anti-PD1 is a promising strategy to improve lung cancer therapy.

The combination of an innovative dry powder for inhalation and a standard cisplatin-based chemotherapy in view of therapeutic intensification against lung tumours.

Cisplatin is one of the most commonly used chemotherapy in lung cancer despite its high nephrotoxicity leading to an administration only every 3-4 weeks. This study is the first report of a preclinical investigation of therapeutic intensification combining a cisplatin dry powder for inhalation (CIS-DPI) with an intravenous (iv) cisplatin-based treatment. CIS-DPI with 50% cisplatin content (CIS-DPI-50) was developed using lipid excipients through scalable processes (high-speed and high-pressure homogenization and spray-drying). CIS-DPI-50 showed good aerodynamic performance (fine particle fraction of ~ 55% and a mass median aerodynamic particle size of ~ 2 µm) and a seven-fold increase and decrease in Cmax in the lungs and in plasma, respectively, in comparison with an iv cisplatin solution (CIS-iv) in healthy mice. Finally, the addition of CIS-DPI-50 to the standard cisplatin/paclitaxel iv doublet increased the response rate (67% vs 50%), decreased the tumour growth and prolonged the median survival (31 vs 21 days), compared to the iv doublet in the M109 lung carcinoma model tending to demonstrate a therapeutic intensification of cisplatin.

Inhaled cytotoxic chemotherapy: clinical challenges, recent developments, and future prospects.

INTRODUCTION: Since 1968, inhaled chemotherapy has been evaluated and has shown promising results up to phase II but has not yet reached the market. This is due to technological and clinical challenges that require to be overcome with the aim of optimizing the efficacy and the tolerance of drug to re-open new developments in this field. Moreover, recent changes in the therapeutic standard of care for treating the patient with lung cancer also open new opportunities to combine inhaled chemotherapy with standard treatments. AREAS COVERED: Clinical and technological concerns are highlighted from the reported clinical trials made with inhaled cytotoxic chemotherapies. This work then focuses on new pharmaceutical developments using dry powder inhalers as inhalation devices and on formulation strategies based on controlled drug release and with sustained lung retention or based on nanomedicine. Finally, new clinical strategies are described in regard to the impact of the immunotherapy on the patient's standard of care. EXPERT OPINION: The choice of the drug, inhalation device, and formulation strategy as well as the position of inhaled chemotherapy in the patient's clinical care are crucial factors in optimizing local tolerance and efficacy as well as in its scalability and applicability in clinical practice.

Deciphering the chemical instability of sphaeropsidin A under physiological conditions - degradation studies and structural elucidation of the major metabolite.

The fungal metabolite sphaeropsidin A (SphA) has been recognised for its promising cytotoxicity, particularly towards apoptosis- and multidrug-resistant cancers. Owing to its intriguing activity, the development of SphA as a potential anticancer agent has been pursued. However, this endeavour is compromised since SphA exhibits poor physicochemical stability under physiological conditions. Herein, SphA's instability in biological media was explored utilizing LC-MS. Notably, the degradation tendency was found to be markedly enhanced in the presence of amino acids in the cell medium utilized. Furthermore, the study investigated the presence of degradation adducts, including the identification, isolation and structural elucidation of a major degradation metabolite, (4R)-4,4',4'-trimethyl-3'-oxo-4-vinyl-4',5',6',7'-tetrahydro-3'H-spiro[cyclohexane-1,1'-isobenzofuran]-2-ene-2-carboxylic acid. Considering the reduced cytotoxic potency of aged SphA solutions, as well as that of the isolated degradation metabolite, the reported antiproliferative activity has been attributed primarily to the parent compound (SphA) and not its degradation species. The fact that SphA continues to exhibit remarkable bioactivity, despite being susceptible to degradation, motivates future research efforts to address the challenges associated with this instability impediment.

The Position of Inhaled Chemotherapy in the Care of Patients with Lung Tumors: Clinical Feasibility and Indications According to Recent Pharmaceutical Progresses.

Despite new treatment modalities, including targeted therapies and checkpoint inhibitors, cytotoxic chemotherapy remains central in the care of patients with lung tumors. Use of the pulmonary route to deliver chemotherapy has been proved to be feasible and safe in phase I, Ib/IIa and II trials for lung tumors, with the administration of drug doses to the lungs without prior distribution in the organism. The severe systemic toxicities commonly observed with conventional systemic chemotherapy are consequently reduced. However, development has failed in phase II at best. This review first focuses on the causes of failure of inhaled chemotherapy. It then presents new promising technologies able to take up the current challenges. These technologies include the use of a dry powder inhaler or a smart nebulizer with advanced drug formulations such as controlled-release formulations and nanomedicine. Finally, the potential position of inhaled chemotherapy in patient care is discussed and some indications are proposed based on the literature.

New Folate-Grafted Chitosan Derivative To Improve Delivery of Paclitaxel-Loaded Solid Lipid Nanoparticles for Lung Tumor Therapy by Inhalation.

Inhaled chemotherapy for the treatment of lung tumors requires that drug delivery systems improve selectivity for cancer cells and tumor penetration and allow sufficient lung residence. To this end, we developed solid lipid nanoparticles (SLN) with modified surface properties. We successfully synthesized a new folate-grafted copolymer of polyethylene glycol (PEG) and chitosan, F-PEG-HTCC, with a PEG-graft ratio of 7% and a molecular weight range of 211-250 kDa. F-PEG-HTCC-coated, paclitaxel-loaded SLN were prepared with an encapsulation efficiency, mean diameter, and zeta potential of about 100%, 250 nm, and +32 mV, respectively. The coated SLN entered folate receptor (FR)-expressing HeLa and M109-HiFR cells in vitro and M109 tumors in vivo after pulmonary delivery. The coated SLN significantly decreased the in vitro half-maximum inhibitory concentrations of paclitaxel in M109-HiFR cells (60 vs 340 nM, respectively). We demonstrated that FR was involved in these improvements, especially in M109-HiFR cells. After pulmonary delivery in vivo, the coated SLN had a favorable pharmacokinetic profile, with pulmonary exposure to paclitaxel prolonged to up to 6 h and limited systemic distribution. Our preclinical findings therefore demonstrated the positive impact of the coated SLN on the delivery of paclitaxel by inhalation.

Sensitization of glioblastoma tumor micro-environment to chemo- and immunotherapy by Galectin-1 intranasal knock-down strategy.

In this study, we evaluated the consequences of reducing Galectin-1 (Gal-1) in the tumor micro-environment (TME) of glioblastoma multiforme (GBM), via nose-to-brain transport. Gal-1 is overexpressed in GBM and drives chemo- and immunotherapy resistance. To promote nose-to-brain transport, we designed siRNA targeting Gal-1 (siGal-1) loaded chitosan nanoparticles that silence Gal-1 in the TME. Intranasal siGal-1 delivery induces a remarkable switch in the TME composition, with reduced myeloid suppressor cells and regulatory T cells, and increased CD4+ and CD8+ T cells. Gal-1 knock-down reduces macrophages' polarization switch from M1 (pro-inflammatory) to M2 (anti-inflammatory) during GBM progression. These changes are accompanied by normalization of the tumor vasculature and increased survival for tumor bearing mice. The combination of siGal-1 treatment with temozolomide or immunotherapy (dendritic cell vaccination and PD-1 blocking) displays synergistic effects, increasing the survival of tumor bearing mice. Moreover, we could confirm the role of Gal-1 on lymphocytes in GBM patients by matching the Gal-1 expression and their T cell signatures. These findings indicate that intranasal siGal-1 nanoparticle delivery could be a valuable adjuvant treatment to increase the efficiency of immune-checkpoint blockade and chemotherapy.

Platinum pharmacokinetics in mice following inhalation of cisplatin dry powders with different release and lung retention properties.

Pharmacokinetics of cisplatin administered by the pulmonary route were established in mice using dry powders inhaler (DPI) formulations showing immediate (F1) and controlled release (CR, solid lipid microparticles) in vitro, without (F2) or with PEGylated excipients (F3, F4). Formulation administration was realized using dry powder blends (correspondingly named thereafter F1B to F4B) able to reproducibly deliver particles in vivo using a DP-4M Dry Powder Insufflator™. Their platinum pharmacokinetics were established over 48h in lungs, total blood and non-target organs vs. IV and endotracheal nebulization (EN). EN and F1B were rapidly distributed from the lungs (t1/2i 2.6 and 5.0min). F2B was eliminated in ∼1h (t1/2i 9.0min). F3B lung retention was sustained for ∼7h (t1/2i 59.9min), increasing lung AUC 11-, 4- and 3-fold vs. IV, F1B and F2B. Total blood tmax were higher and AUC and Cmax lower using the pulmonary route vs. IV. Kidney Cmax was reduced 6-, 2- and 3-fold for F1B, F2B and F3B. AUC in kidneys were 2- to 3-fold lower for F1B and F2Bvs. IV but comparable for IV vs. F3B, probably because of kidney saturation. PEGylated solid lipid microparticles provided cisplatin particles with interesting lung retention and CR properties.

Development of controlled-release cisplatin dry powders for inhalation against lung cancers.

The present study focuses on the development of dry powders for inhalation as adjuvant chemotherapy in lung cancer treatment. Cisplatin was chosen as a potential candidate for a local treatment as it remains the main platinum component used in conventional chemotherapies, despite its high and cumulative systemic toxicities. Bulk cisplatin was reduced to submicron sizes using high-pressure homogenization, mixed with a solubilized lipid and/or PEGylated component and then spray-dried to produce controlled-release dry powder formulations. The obtained formulations were characterized for their physicochemical properties (particle size and morphology), aerodynamic performance and release profiles. Cisplatin content and integrity were assessed by electrothermal atomic absorption spectrometry and 195Pt nuclear magnetic resonance spectroscopy. DPI formulations with cisplatin contents ranging from 48.5 to 101.0% w/w exhibited high fine particle fractions ranging from 37.3% to 51.5% of the nominal dose. Formulations containing cisplatin microcrystals dispersed in solid lipid microparticles based on acceptable triglycerides for inhalation and PEGylated excipients showed a controlled-release for more than 24h and a limited burst effect. These new formulations could provide an interesting approach to increasing and prolonging drug exposure in the lung while minimizing systemic toxicities.

Development and evaluation of well-tolerated and tumor-penetrating polymeric micelle-based dry powders for inhaled anti-cancer chemotherapy.

Despite the direct access to the lung offered by the inhalation route, drug penetration into lung tumors could remain an important issue. In this study, folate-polyethylene glycol-hydrophobically-modified dextran (F-PEG-HMD) micelles were developed as an effective pulmonary drug delivery system to reach and penetrate lung tumors and cancer cells. The F-PEG-HMD micelles were able to enter HeLa and M109-HiFR, two folate receptor-expressing cancer cell lines, in vitro, and in vivo after administration by inhalation to orthotopic M109-HiFR lung tumor grafted mice. Paclitaxel-loaded F-PEG-HMD micelles characterized in PBS by a Z-average diameter of ∼50 nm and a zeta potential of ∼-4 mV were prepared with an encapsulation efficiency of ∼100%. The loaded micelles reduced HeLa and M109-HiFR cell growth, with half maximal inhibitory concentrations of 37 and 150 nM, respectively. Dry powders embedding the paclitaxel-loaded F-PEG-HMD micelles were developed by spray-drying. In vitro, good deposition profiles were obtained, with a fine particle fraction of up to 50% and good ability to re-disperse the micelles in physiological buffer. A polymeric micelle-based dry powder without paclitaxel was well-tolerated in vivo, as assessed in healthy mice by determination of total protein content, cell count, and cytokine IL-1ß, IL-6, and TNF-α concentrations in bronchoalveolar lavage fluids.

Development of siRNA-loaded chitosan nanoparticles targeting Galectin-1 for the treatment of glioblastoma multiforme via intranasal administration.

Galectin-1 (Gal-1) is a naturally occurring galactose-binding lectin, which is overexpressed in glioblastoma multiforme (GBM). Gal-1 is associated with tumor progression, and is a potent immune suppressor in the tumor micro-environment. To inhibit Gal-1 in GBM, an effective therapy is required that reaches the central nervous system tumor, with limited systemic effects. In this study, we report for the first time that concentrated chitosan nanoparticle suspensions can deliver small interfering RNA (siRNA) into the central nervous system tumor within hours after intranasal administration. These nanoparticles are able to complex siRNA targeting Gal-1 to a high percentage, and protect them from RNAse degradation. Moreover, a successful intracellular delivery of anti-Gal-1 siRNA resulted in a decreased expression of Gal-1 in both murine and human GBM cells. Sequence specific RNAinterference, resulted in more than 50% Gal-1 reduction in tumor bearing mice. This study indicates that the intranasal pathway is an underexplored transport route for delivering siRNA-based therapies targeting Gal-1 in the treatment of GBM.

New dry powders for inhalation containing temozolomide-based nanomicelles for improved lung cancer therapy.

Besides the numerous advantages of a chemotherapy administered by the inhalation route for lung cancer therapy, dry powder for inhalation (DPI) offers many advantages compared to other techniques and seems to be a technique that is well-adapted to an anticancer treatment. DPI formulations were developed using the cytotoxic drug temozolomide and a new folate-grafted self-assembling copolymer, a conjugate of three components, folate-polyethylene glycol-hydrophobically-modified dextran (F-PEG-HMD). F-PEG-HMD was synthesized using carbodiimide-mediated coupling chemistry in three main steps. F-PEG-HMD was characterized by 1H-NMR, mass spectrometry and thermal analysis. F-PEG-HMD presented a critical micellar concentration in water of 4x10-7 M. F-PEG-HMD nanomicelles were characterized by a trimodal particle size distribution with Z-average diameter of 83±1 nm in water. Temozolomide-loaded nanomicelles were prepared by solubilization of F-PEG-HMD in the presence of temozolomide. Temozolomide solubility in water was increased in the presence of F-PEG-HMD (2-fold increase in molar solubility) which could potentially lead to increased local concentrations in the tumor site. The temozolomide-loaded F-PEG-HMD nanomicelles were characterized by a Z-average diameter of ~50 to ~60 nm, depending on the F-PEG-HMD concentration used. The nanomicelles were then spray-dried to produce dry powders. Temozolomide remained stable during all the formulation steps, confirmed by similar in vitro anticancer properties for the DPI formulations and a raw temozolomide solution. Two of the developed DPI formulations were characterized by good aerodynamic properties (with a fine particle fraction of up to 50%) and were able to release the F-PEG-HMD nanomicelles quickly in aqueous media. Moreover, in vitro, the two DPI formulations showed wide pulmonary deposition in the lower respiratory tract where adenocarcinomas are more often found. The present study, therefore, shows that F-PEG-HMD-based dry powders for inhalation could constitute an interesting drug delivery system able to release nanomicelles that are useful in adenocarcinomas that overexpress folate receptors.

Formulations for Intranasal Delivery of Pharmacological Agents to Combat Brain Disease: A New Opportunity to Tackle GBM?

Despite recent advances in tumor imaging and chemoradiotherapy, the median overall survival of patients diagnosed with glioblastoma multiforme does not exceed 15 months. Infiltration of glioma cells into the brain parenchyma, and the blood-brain barrier are important hurdles to further increase the efficacy of classic therapeutic tools. Local administration methods of therapeutic agents, such as convection enhanced delivery and intracerebral injections, are often associated with adverse events. The intranasal pathway has been proposed as a non-invasive alternative route to deliver therapeutics to the brain. This route will bypass the blood-brain barrier and limit systemic side effects. Upon presentation at the nasal cavity, pharmacological agents reach the brain via the olfactory and trigeminal nerves. Recently, formulations have been developed to further enhance this nose-to-brain transport, mainly with the use of nanoparticles. In this review, the focus will be on formulations of pharmacological agents, which increase the nasal permeation of hydrophilic agents to the brain, improve delivery at a constant and slow release rate, protect therapeutics from degradation along the pathway, increase mucoadhesion, and facilitate overall nasal transport. A mounting body of evidence is accumulating that the underexplored intranasal delivery route might represent a major breakthrough to combat glioblastoma.

New co-spray-dried tobramycin nanoparticles-clarithromycin inhaled powder systems for lung infection therapy in cystic fibrosis patients.

The aim of the study was to produce easily dispersible and porous agglomerates of tobramycin nanoparticles surrounded by a matrix composed of amorphous clarithromycin. Nanoparticles of tobramycin with a median particle size of about 400 nm were produced by high-pressure homogenisation. The results from the spray-dried powders showed that the presence of these nanoparticles enhanced powder dispersion during inhalation. Moreover, local drug deposition profiles were similar for the two antibiotics, allowing them to reach the target simultaneously. The dissolution-release profiles showed that tobramycin and clarithromycin might dissolve without any difficulties in the lung. The fine particle fraction increased from 35% and 31% for the physical blend for tobramycin and clarithromycin, respectively, to 63% and 62% for the spray-dried formulation containing nanoparticles. These new formulations, showing high lung deposition properties, even at sub-optimal inspiratory flow rates, represent a great possibility for advancing pulmonary drug administration and local therapy of lung infections.