Paving the way for phage therapy using novel drug delivery approaches.

Bacterial resistance against antibiotics is an emergent medical issue. The development of novel therapeutic approaches is urgently needed and, in this context, bacteriophages represent a promising strategy to fight multi resistant bacteria. However, for some applications, bacteriophages cannot be used without an appropriate drug delivery system which increases their stability or provides an adequate targeting to the site of infection. This review summarizes the main application routes for bacteriophages and presents the new delivery approaches designed to increase phage's activity. Clinical successes of these formulations are also highlighted. Globally, this work paves the way for the design and optimization of nano and micro delivery systems for phage therapy.

[Viruses for health: Bacteriophages]. / Les virus au service de la santé : les bactériophages.

Bacteriophages are naturally occurring viruses that specifically target bacteria. They are widely distributed in the environment. The concept of phage therapy is to isolate phages, characterize them, cultivate them and then purify them to treat bacterial infections. There is currently a revival of phage therapy, and its implementation presupposes the availability of active phages of pharmaceutical quality. From a regulatory point of view, the status of phages is not yet clearly defined by the authorities. The availability of phages produced by the pharmaceutical industry and through academic development programs such as the PHAGEinLYON program represents a breakthrough in the development of phage therapy. Prosthetic joint infections and digestive diseases seem to be relevant indications, but preclinical studies and randomized clinical trials are now needed to be done.

Title: Les virus au service de la santé : les bactériophages. Abstract: Les bactériophages sont des virus naturels très répandus dans l'environnement qui ciblent spécifiquement les bactéries. Leur utilisation en médecine, connue sous le terme phagothérapie, consiste à les isoler, les caractériser, les cultiver, puis les purifier pour traiter des infections bactériennes. Il existe actuellement un renouveau pour la thérapie phagique, et sa mise en œuvre présuppose de disposer de phages actifs de qualité pharmaceutique. D'un point de vue réglementaire, le statut des phages n'est pas encore clairement défini par les autorités, mais la mise à disposition de phages produits par l'industrie pharmaceutique et les programmes de développement académiques, comme le programme PHAGEinLYON, constituent un tournant dans le déploiement de la phagothérapie.

Past and Future of Phage Therapy and Phage-Derived Proteins in Patients with Bone and Joint Infection.

Phage-derived therapies comprise phage therapy and the use of phage-derived proteins as anti-bacterial therapy. Bacteriophages are natural viruses that target specific bacteria. They were proposed to be used to treat bacterial infections in the 1920s, before the discovery and widespread over-commercialized use of antibiotics. Phage therapy was totally abandoned in Western countries, whereas it is still used in Poland, Georgia and Russia. We review here the history of phage therapy by focusing on bone and joint infection, and on the development of phage therapy in France in this indication. We discuss the rationale of its use in bacterial infection and show the feasibility of phage therapy in the 2020s, based on several patients with complex bone and joint infection who recently received phages as compassionate therapy. Although the status of phage therapy remains to be clarified by health care authorities, obtaining pharmaceutical-grade therapeutic phages (i.e., following good manufacturing practice guidelines or being "GMP-like") targeting bacterial species of concern is essential. Moreover, multidisciplinary clinical expertise has to determine what could be the relevant indications to perform clinical trials. Finally "phage therapy 2.0" has to integrate the following steps: (i) follow the status of phage therapy, that is not settled and defined; (ii) develop in each country a close relationship with the national health care authority; (iii) develop industrial-academic partnerships; (iv) create academic reference centers; (v) identify relevant clinical indications; (vi) use GMP/GMP-like phages with guaranteed quality bioproduction; (vii) start as salvage therapy; (vii) combine with antibiotics and adequate surgery; and (viii) perform clinical trials, to finally (ix) demonstrate in which clinical settings phage therapy provides benefit. Phage-derived proteins such as peptidoglycan hydrolases, polysaccharide depolymerases or lysins are enzymes that also have anti-biofilm activity. In contrast to phages, their development has to follow the classical process of medicinal products. Phage therapy and phage-derived products also have a huge potential to treat biofilm-associated bacterial diseases, and this is of crucial importance in the worldwide spread of antimicrobial resistance.

Safety of Tedizolid as Suppressive Antimicrobial Therapy for Patients With Complex Implant-Associated Bone and Joint Infection due to Multidrug-Resistant Gram-Positive Pathogens: Results From the TediSAT Cohort Study.

A prospective cohort study was conducted to evaluate long-term safety of tedizolid as suppressive antimicrobial treatment in patients with implant-associated bone and joint infection caused by multidrug-resistant gram-positive pathogens. Seventeen patients received tedizolid with a median duration of treatment of 6 months. No patients developed a serious adverse event.

Blue Dye Embolization of Renal Tumor: A New Technique to Improve Tumor Localization During Laparoscopic Partial Nephrectomy.

Purpose: To improve the tumor localization during laparoscopic surgery, we describe an innovative technique involving superselective intra-arterial injection of blue dye in tumoral vessels to color the tumor before surgical enucleation. Materials and Methods: The dye injection was performed at the same time as superselective embolization, immediately before laparoscopic surgery in a hybrid operating room. We used this new treatment sequence on 50 consecutive patients. Results: The selective intra-arterial injection of an emulsion of blue dye and lipiodol was feasible in 46 (92%) cases and well tolerated, followed by superselective embolization of the tumor vessels with glue or coils. The tumor was easily localized during surgery due to the blue coloration. Tumor coloration was not associated with postoperative complication, especially allergic reaction or renal failure. Pathologic analysis of the tumor was not modified by the coloration and all tumors had negative surgical margins. Conclusions: The preoperative dye localization is a feasible, safe, and accurate procedure. This combined approach reduces the difficulty of surgery and increases patient safety.

Di-O-lauroyl-decitabine-lipid nanocapsules: toward extending decitabine activity.

BACKGROUND: Acute myeloid leukemia mainly affects adult patients. Complete remission for patients younger than 60 years, who are candidates for standard induction therapy, is achieved in 60%-80% of cases. However, the prognosis is still poor for older patients, who are unfit for intensive chemotherapy, and only a few therapies are available. Hypomethylating agents, such as decitabine, are approved for such patients. The current dosing regimen consists of one administration per day, for 5 days, each 4 weeks. METHODS: Here, we present the synthesis of a decitabine prodrug, combined with its encapsulation into a lipid-based nanocapsule formulation. Decitabine (C12)2 was synthetized, then loaded into nanocapsules. Its stability in phosphate buffer ans human plasma was checked. Its activity was evaluated by Cell proliferation assays and cell-cycle analysis on human erythroleukemia cells. Then its pharmacokinetics was determined on a rat model. RESULTS: Decitabine (C12)2 was obtained with a yield of 50%. Drug loading into nanocarriers of 27.45±0.05 nm was 5.8±0.5 mg/mL. The stability of decitabine was improved and its activity on leukemia cells was not altered. Finally, pharmacokinetics studies showed a prolonged mean residence time of the drug. CONCLUSION: Decitabine (C12)2 as a prodrug showed high encapsulation efficiency, a good stability in plasma with no impact on its activity on leukemia cells and improved pharmacokinetics.

Advances in treatment formulations for acute myeloid leukemia.

Acute myeloid leukemia (AML) is the most common cause of leukemia-related mortality. The combination of cytarabine and anthracycline has been the gold standard of treatment over the past 40 years, but the distribution of the drugs in the body leads to severe adverse effects. Poor prognosis of older patients with AML is the consequence not only of comorbidities, but also of chemoresistance resulting from frequent secondary AML. Numerous strategies using nanotechnologies are in development to improve drug targeting, pharmacokinetics, administration route, chemoresistance, and adverse effects generally observed. Among the four new drugs approved for AML by the US Food and Drug Administration (FDA) in 2017, Vyxeos® is a novel liposomal formulation of historical AML drugs. Here, we review current AML treatments and discuss how the development of new formulations will change the therapeutic armamentarium.

Development and in vitro evaluations of new decitabine nanocarriers for the treatment of acute myeloid leukemia.

Decitabine is a hydrophilic drug that acts by hypomethylating DNA. Decitabine is used in Europe for the treatment of acute myeloid leukemia (AML) in patients aged ≥65 years. However, it can only be administered intravenously due to very low oral bioavailability and a large distribution volume. Oral administration would allow outpatient treatment, improving quality of life and reducing treatment costs. The present study proposes to develop lipid nanocapsules (LNCs), originally designed for lipophilic drugs, to encapsulate decitabine. Two different formulations of LNCs were designed: LNCs based on a high proportion of Transcutol® HP (THP-LNCs) and LNCs associated with a mixture of Transcutol® HP and Tween® 80 (THP-T80-LNCs). The second formulation had a diameter of 26.5±0.5 nm, high encapsulation efficiency (>85%), and a drug payload of 472±64 µg/mL. Decitabine-loaded THP-T80-LNC cytotoxicity was evaluated on two AML cell lines depending on their decitabine resistance: HEL (not resistant) and HL-60 (resistant). The permeability of decitabine-loaded THP-T80-LNCs was also evaluated on Caco-2 cell monolayers. Decitabine cytotoxicity against HEL and HL-60 was higher when decitabine was loaded in THP-T80-LNCs than when free. Apparent permeability on Caco-2 cell monolayers was also increased, suggesting a potentially useful formulation to increase the oral bioavailability of decitabine.

Stability of micafungin sodium solutions at different concentrations in glass bottles and syringes.

Micafungin is a costly treatment and packaging of 50 mg or 100 mg bottles only are available, while doses lower than 5 mg and 20 mg are often necessary in neonates and paediatrics patients, respectively. The stability of micafungin sodium in polypropylene syringes and glass bottles was studied at different concentrations. Solutions of micafungin diluted with NaCl 0.9% were prepared in glass bottles (20 and 10 mg/mL) or syringes (1 and 0.5 mg/mL) and stored at 25 °C, 60% humidity (RH), in the dark (ICH conditions). Solutions were also exposed to heat (70 °C) or alkaline solution (NaOH) in order to force degradation. Samples were analysed at days 1, 5, 8 (for bottles) and also 15 (for syringes) after the preparation and assayed in triplicate. Stability was studied using a stability-indicating high-performance liquid chromatographic method. Syringes stored at 25 °C retained over 90% of their initial concentration over the study period. Temperature and alkaline conditions had significant effect on the stability of micafungin, leading to apparition of degradation products. Moreover, sub visible particles were in the specification of the European Pharmacopeia along 15 days. To conclude, micafungin diluted in NaCl 0.9% and stored in polypropylene syringes was chemically stable for at least 15 days at 25 °C in the dark.

Design and stability study of a paediatric oral solution of methotrexate 2 mg/ml.

Oral paediatric forms development by pharmaceutical industry is still insufficient. The present study was performed to propose an adapted and pleasant formulation of liquid oral formulation of MTX. The solution is composed of injectable methotrexate, water, Ora Sweet(®) and sodium bicarbonate. After 120 days storage, pH remained stable at about 8 in all formulations, insuring no risk of MTX precipitation. MTX content in solution formulation, determined by high performance liquid chromatography measurements, remained in the specifications of >90% of the initial concentration when stored at 4 and 25°C. Forced degradation of MTX by heat and acidic conditions allowed formation and detection of degradation products by the analytical method. Microbial study of the preparation shows that the solution remains in the specifications during all the storage, or after one sample each week during one month, eventually indicating the microbial properties are not affected by patient use. To conclude, we here propose a new MTX liquid formulation stable for at least 120 days.