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Mycobacterium avium complex (MAC) is considered a paramount microbe, especially in East Asia, including Japan. The commonly used commercial Minimum Inhibitory Concentrations (MIC) assay using Middlebrook 7H9 (7H9) medium deviates from the latest Clinical and Laboratory Standards Institute (CLSI) guidelines. Alternatively, measurement with cation-adjusted Mueller-Hinton broth (CAMHB) that conforms to CLSI standards is not yet widely available. Following the approval and commercialization of amikacin liposome inhalation suspension (ALIS) in 2021, a more precise evaluation of amikacin (AMK) susceptibility in MAC is necessary for treatment decisions. In the present study, 33 sputum samples were extracted from 27 patients, and MICs of AMK were compared between the frequently used 7H9 and the recommended CAMHB of the isolated MAC strains. The history of exposure to aminoglycosides for each sample was also added as clinical information. The findings indicated that there was only an 18% concordance rate in MIC between the two media, with 19 samples (58%) indicating lower MICs in 7H9 relative to CAMHB. The 17 samples had a history of exposure to aminoglycosides for periods ranging from 1.5 to 28 months. Specifically, 10 samples were exposed to amikacin by inhalation and intravenous injection, and the remaining seven samples had a history of ALIS inhalation. Samples with a prior utilization of aminoglycosides were significantly predisposed to developing resistance to ALIS compared to those without such a history (P = 0.046). Physicians are encouraged to scrutinize the findings of susceptibility testing utilizing CLSI-endorsed MIC assay using CAMHB medium to ascertain the optimal therapeutic approach.

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The AlTiVCuN coatings were deposited by magnetron sputtering with anode layer ion source (ALIS) assistance, and the microstructure and mechanical properties were significantly affected by the ion source power. With increasing the ion source power from 0 to 1.0 kW, the deposition rate decreased from 2.6 to 2.1 nm/min, and then gradually increased to 4.0 nm/min at 3.0 kW, and the surface roughness gradually decreased from 28.7 nm at 0 kW to 9.0 nm at 3.0 kW. Due to the enhanced ion bombardment effect, the microstructure of the coatings changed from a coarse into a dense columnar structure at 1.0 kW, and the grain size increased at higher ion source powers. All the coatings exhibited c-TiAlVN phase, and the preferred orientation changed from the (220) to the (111) plane at 3.0 kW. Due to the low Cu contents (1.0~3.1 at.%), the Cu atoms existed as an amorphous phase in the coatings. Due to the microstructure densification and high residual stress, the highest hardness of 32.4 GPa was achieved for the coating deposited at 1.0 kW.

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Non-tuberculous mycobacterial pulmonary disease (NTM-PD) poses a substantial patient, healthcare, and economic burden. Managing NTM-PD remains challenging, and factors contributing to this include morphological, species, and patient characteristics as well as the treatment itself. This narrative review focusses on the challenges of NTM-PD from the perspective of the organism and the disease process. Morphological characteristics of non-tuberculous mycobacteria (NTM), antimicrobial resistance mechanisms, and an ability to evade host defences reduce NTM susceptibility to many antibiotics. Resistance to antibiotics, particularly macrolides, is of concern, and is associated with high mortality rates in patients with NTM-PD. New therapies are desperately needed to overcome these hurdles and improve treatment outcomes in NTM-PD. Amikacin liposome inhalation suspension (ALIS) is the first therapy specifically developed to treat refractory NTM-PD caused by Mycobacterium avium complex (MAC) and is approved in the US, EU and Japan. It provides targeted delivery to the lung and effective penetration of macrophages and biofilms and has demonstrated efficacy in treating refractory MAC pulmonary disease (MAC-PD) in the Phase III CONVERT study. Several other therapies are currently being developed including vaccination, bacteriophage therapy, and optimising host defences. Newly developed antibiotics have shown potential activity against NTM-PD and include benzimidazole, delamanid, and pretomanid. Antibiotics commonly used to treat other infections have also been repurposed for NTM-PD, including clofazimine and bedaquiline. Data from larger-scale studies are needed to determine the potential of many of these therapies for treating NTM-PD.

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BACKGROUND: Mycobacterium avium complex lung disease (MAC-LD) is an infection that is increasing in frequency, associated with substantial disease burden, and often refractory to treatment. Amikacin liposome inhalation suspension (ALIS) is the first therapy approved for refractory MAC-LD. In the CONVERT study of adult patients with refractory MAC-LD, adding ALIS to a multidrug background regimen showed evidence of MAC infection elimination in sputum by month 6, which was maintained in most patients through the end of treatment (≤ 12 months post-conversion). This study assessed changes in healthcare resource utilization (HCRU) among patients initiating ALIS in real-world settings. METHODS: This retrospective cohort study of the All-Payer Claims Database (October 2018-April 2020) included patients aged ≥ 18 years with ≥ 1 pharmacy claim for ALIS and ≥ 12 months of continuous health plan enrollment pre- and post-ALIS initiation. Respiratory disease-related (and all-cause) HCRU (hospitalizations, length of stay [LOS], emergency department [ED] visits, and outpatient office visits) were compared 12 months pre- and post-ALIS initiation. Outcomes were reported at 6-month intervals; 0-6 months pre-ALIS initiation was the reference period for statistical comparisons. RESULTS: A total of 331 patients received ALIS, with HCRU highest in the 6 months pre-ALIS initiation. Compared with 26.9% during the reference period, respiratory-related hospitalizations decreased to 19.3% (P < 0.01) and 15.4% (P < 0.0001) during 0-6 and 7-12 months post-ALIS initiation, respectively. Mean number of respiratory disease-related hospitalizations per patient/6-month period decreased from 1.0 (reference period) to 0.6 (P < 0.0005) at both timepoints post-ALIS initiation. A similar pattern was observed for all-cause hospitalizations and hospitalizations per patient/6-month period (both P < 0.005). Reductions in all-cause and respiratory disease-related LOS post-ALIS initiation were significant (both P < 0.05). ED visits were few and unchanged during the study. Significant reductions per patient/6-month period in all-cause and respiratory-related outpatient office visits were observed post-ALIS initiation (all P < 0.01). CONCLUSIONS: In this first real-world study of ALIS, respiratory disease-related (and all-cause) hospitalizations and outpatient visits were reduced in the 12 months following ALIS initiation. The results of this study provide HCRU-related information to better understand the impact of initiating ALIS treatment. TRIAL REGISTRATION: Not appliable.

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Purpose: Amikacin liposome inhalation suspension (ALIS), which efficiently allows amikacin to reach the pulmonary periphery for effect while minimising systemic adverse effects, was recently approved for treating Mycobacterium avium complex (MAC) infections. The international Phase 3 open-label clinical trials showed promising results, contributing to sputum culture conversion, but few studies have examined the efficacy and adverse effects of ALIS using real-world data. We identified the clinical outcome and adverse effects of ALIS in the early phase of treatment, for more effective and safe use in clinical practice. Patients and Methods: The study population consisted of patients with MAC lung disease (MAC-LD), introduced to ALIS therapy after July 2021 at Keio University Hospital due to poor response to multidrug therapy. The sputum smear/culture results, symptoms, adverse effects, and the serum amikacin concentrations of the early phase of ALIS inhalation therapy were examined. Results: A total of 11 patients (9 women; median age 64.6 years) were included in this study. The median disease duration of MAC-LD was 13.7 years, and all patients exhibited a positive culture at the beginning of ALIS inhalation. Three of the six patients (50.0%) who were initially sputum-smear-positive were confirmed to have become sputum-smear-negative within one month, including one culture conversion. ALIS inhalation therapy caused some adverse effects in nine patients (81.8%); however, no serious systemic adverse effects were observed. The most common adverse effect was hoarseness (72.7%), which mostly occurred around 1 week after initiation. The medians of peak serum amikacin concentrations were 1.4 and 2.3 µg/mL for the first and third inhalations, respectively. Trough serum concentrations just before the third inhalation were <1.2 µg/mL in all patients. Conclusion: ALIS therapy might be a treatment option for patients with refractory MAC infection with long disease duration and a poor response to guideline-based therapy.

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A 56-year-old woman with pulmonary Mycobacterium avium complex disease was started on inhalation liposomal amikacin. One month later, she developed hoarseness and was diagnosed with laryngitis. The laryngitis healed immediately after treatment discontinuation, and no recurrence occurred even after resuming intermittent inhalation.

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Pulmonary administration route has been extensively exploited for the treatment of local lung diseases such as asthma, chronic obstructive pulmonary diseases and respiratory infections, and systemic diseases such as diabetes. Most inhaled medicines could be cleared rapidly from the lungs and their therapeutic effects are transit. The inhaled medicines with extended pulmonary exposure may not only improve the patient compliance by reducing the frequency of drug administration, but also enhance the clinical benefits to the patients with improved therapeutic outcomes. This article systematically reviews the physical and chemical strategies to extend the pulmonary exposure of the inhaled medicines. It starts with an introduction of various physiological and pathophysiological barriers for designing inhaled medicines with extended lung exposure, which is followed by recent advances in various strategies to overcome these barriers. Finally, the applications of the inhaled medicines with extended lung exposure for the treatment of various diseases and the safety concerns associated to various strategies to extend the pulmonary exposure of the inhaled medicines are summarized.

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The typical radiographic presentation for Mycobacterium avium complex lung disease (MAC-LD) is either nodular bronchiectasis or cavitary lung disease. The former is seen most commonly in middle-aged or elderly Caucasian females with the characteristic asthenic phenotype, and the latter in middle-aged male smokers with COPD. We present the case of a young, otherwise healthy woman, with no significant risk factors, who was incidentally found to have MAC-LD with associated bronchiectasis. The patient's treatment and clinical course over a period of 5 years was marred by erratic follow up, intermittent treatment and poor adherence to guideline-based antibiotic therapy. Over this period of time, the patient developed significant worsening of her MAC-LD, macrolide resistance and failure to thrive. Upon presentation 5 years after her initial diagnosis, she had developed MAC-Pleural Disease with an empyema and broncho-pleural fistula. This case illustrates the progression of MAC-LD from nodular bronchiectasis to cavitary disease and pleural involvement leading to clinical deterioration. It highlights challenges related to short and long term management of macrolide resistant MAC-LD and the importance and need for surgical intervention and drainage procedures in patient with MAC-Pleural Disease.

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The purpose of these studies was to understand the effect on product performance of batch-to-batch variability in both the amikacin liposome inhalation suspension (ALIS) formulation and its delivery device, the Lamira® nebulizer system, designed and manufactured by PARI (PARI Pharma GmbH, Munich, Germany). Three batches of ALIS spanning a range of lipid concentrations (43, 48 and 54 mg/mL) were tested with nine PARI inhalation devices that varied within the production process of the vibrating membrane with respect to hole geometry. Three hole geometry clusters were built including a geometry close to the mean geometry (median) and two geometries deviating from the mean geometry with smaller (smaller) and larger (larger) holes. The output parameters included the nebulization rate, the aerosol droplet size distribution, the liposome vesicle size post-nebulization, and the fraction of amikacin that remained encapsulated post-nebulization. Across the 27 experimental combinations of three formulation batches and nine devices, the nebulization time varied between 12 and 15 min with the fastest nebulization rate occurring with the combination of low lipid concentration and larger hole geometry (0.68 g/min) and the slowest nebulization rate occurring with the combination of high lipid concentration and the smaller hole geometry (0.59 g/min). The mean liposome vesicle size post-nebulization ranged from 269 to 296 nm across all experimental combinations which was unchanged from the control samples (276-292 nm). While all three batches contained > 99% encapsulated amikacin prior to nebulization, the nebulization process resulted in a consistent generation of ~ 35% unencapsulated amikacin (range: 33.8% to 37.6%). There was no statistically significant difference in the generated aerosol particle size distributions. The mass median aerodynamic diameters (MMAD) ranged from 4.78 µm to 4.98 µm, the geometric standard deviations (GSD) ranged from 1.61 to 1.66, and the aerosol fine particle fraction (FPF < 5 µm) ranged from 50.3 to 53.5%. The emitted dose (ED) of amikacin ranged from 473 to 523 mg (80.2 to 89.3% of loaded dose (LD)) and the fine particle dose (FPD < 5 µm) ranged from 244 to 278 mg (41.4 to 47.1% of label claim (LC)). In conclusion, while variations in the lipid concentration of the ALIS formulation and the device hole geometry had a small but significant impact on nebulization time, the critical aerosol performance parameters were maintained and remained within acceptable limits.

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BACKGROUND: . In CLEAR-108-a phase 3, randomised, open-label study-once-daily amikacin liposome inhalation suspension (ALIS) was noninferior to twice-daily tobramycin inhalation solution (TIS) in improving lung function in patients with cystic fibrosis (CF) and chronic Pseudomonas aeruginosa infection after 3 treatment cycles (28 days on/28 days off). The CLEAR-110 extension study (ClinicalTrials.gov: NCT01316276; EudraCT: 2011-000443-24) assessed long-term safety, tolerability, and efficacy of ALIS in eligible patients who completed CLEAR-108. METHODS: . Patients received once-daily ALIS 590 mg for 12 treatment cycles (96 weeks). Patients were grouped by prior treatment: the "prior-ALIS" cohort received ALIS in CLEAR-108, and the "ALIS-naive" cohort received TIS in CLEAR-108. RESULTS: . Overall, 206 patients (prior-ALIS, n=92; ALIS-naive, n=114) entered CLEAR-110 and received ≥1 dose of ALIS. Most patients (88.8%) experienced ≥1 treatment-emergent adverse event (TEAE) through day 672 (end of year 2). Most TEAEs (72.3%) were mild or moderate in severity. Severe TEAEs were reported in 31 patients (15.0%). Two life-threatening TEAEs (haemoptysis; intestinal obstruction) and 1 death (cardiac failure) were reported. Twenty-one patients (10.2%) discontinued treatment due to a TEAE (mostly infective pulmonary exacerbation of CF). Mean change from baseline in forced expiratory volume in 1 second percent predicted at day 672 was -3.1% (prior-ALIS, -4.0%; ALIS-naive, -2.3%). Mean change from baseline in sputum density of P. aeruginosa at day 672 was 0.02 (prior-ALIS, -0.16; ALIS-naive, 0.19) log CFU/g. CONCLUSIONS: . Long-term treatment with ALIS was well tolerated with a favourable adverse event profile and demonstrated continued antibacterial activity in CF patients with chronic P. aeruginosa infection.

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BACKGROUND: In the CONVERT study, treatment with amikacin liposome inhalation suspension (ALIS) added to guideline-based therapy (GBT) met the primary end point of increased culture conversion by month 6 in patients with treatment-refractory Mycobacterium avium complex lung disease (ALIS plus GBT, 29% [65/224] vs GBT alone, 8.9% [10/112]; P < .0001). RESEARCH QUESTION: In patients who achieved culture conversion by month 6 in the CONVERT study, was conversion sustained (negative sputum culture results for 12 months with treatment) and durable (negative sputum culture results for 3 months after treatment) and were there any additional safety signals associated with a full treatment course of 12 months after conversion? STUDY DESIGN AND METHODS: Adults were randomized 2:1 to receive ALIS plus GBT or GBT alone. Patients achieving culture conversion by month 6 continued therapy for 12 months followed by off-treatment observation. RESULTS: More patients randomized to ALIS plus GBT (intention-to-treat population) achieved conversion that was both sustained and durable 3 months after treatment vs patients randomized to GBT alone (ALIS plus GBT, 16.1% [36/224] vs GBT alone, 0% [0/112]; P < .0001). Of the patients who achieved culture conversion by month 6, 55.4% of converters (36/65) in the ALIS plus GBT treated arm vs no converters (0/10) in the GBT alone arm achieved sustained and durable conversion (P = .0017). Relapse rates through 3 months after treatment were 9.2% (6/65) in the ALIS plus GBT arm and 30.0% (3/10) in the GBT alone arm. Common adverse events among ALIS plus GBT-treated patients (dysphonia, cough, dyspnea, hemoptysis) occurred mainly within the first 8 months of treatment. INTERPRETATION: In a refractory population, conversion was sustained and durable in more patients treated with ALIS plus GBT for 12 months after conversion than in those treated with GBT alone. No new safety signals were associated with 12 months of treatment after conversion. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT02344004; URL: www.clinicaltrials.gov.

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Pulmonary administration route has been extensively exploited for the treatment of local lung diseases such as asthma, chronic obstructive pulmonary diseases and respiratory infections, and systemic diseases such as diabetes. Most inhaled medicines could be cleared rapidly from the lungs and their therapeutic effects are transit. The inhaled medicines with extended pulmonary exposure may not only improve the patient compliance by reducing the frequency of drug administration, but also enhance the clinical benefits to the patients with improved therapeutic outcomes. This article systematically reviews the physical and chemical strategies to extend the pulmonary exposure of the inhaled medicines. It starts with an introduction of various physiological and pathophysiological barriers for designing inhaled medicines with extended lung exposure, which is followed by recent advances in various strategies to overcome these barriers. Finally, the applications of the inhaled medicines with extended lung exposure for the treatment of various diseases and the safety concerns associated to various strategies to extend the pulmonary exposure of the inhaled medicines are summarized.

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Rationale: Patients with refractory Mycobacterium avium complex (MAC) lung disease have limited treatment options. In the CONVERT study, amikacin liposome inhalation suspension (ALIS) added to guideline-based therapy (GBT) increased culture conversion rates versus GBT alone by Month 6. Limited data are available regarding >6-month treatment in a refractory population.Objectives: Evaluate 12-month safety, tolerability, and efficacy of ALIS+GBT.Methods: Adults with refractory MAC lung disease not achieving culture conversion by CONVERT Month 6 could enroll in this open-label extension (INS-312) to receive 590 mg once-daily ALIS+GBT for 12 months. Two cohorts enrolled: the "ALIS-naive" cohort included patients randomized to GBT alone in CONVERT, and the "prior-ALIS" cohort included those randomized to ALIS+GBT in CONVERT. Safety and tolerability of ALIS over 12 months (primary endpoint) and culture conversion by Months 6 and 12 were assessed.Results: In the ALIS-naive cohort, 83.3% of patients (n = 75/90) experienced respiratory treatment-emergent adverse events (TEAEs), and 35.6% (n = 32) had serious TEAEs; 26.7% (n = 24) achieved culture conversion by Month 6 and 33.3% (n = 30) by Month 12. In the prior-ALIS cohort, 46.6% of patients (n = 34/73) experienced respiratory TEAEs, and 27.4% (n = 20) had serious TEAEs; 9.6% (n = 7) achieved culture conversion by Month 6 (≤14 mo ALIS exposure) and 13.7% (n = 10) by Month 12 (≤20 mo ALIS exposure). Nephrotoxicity-related TEAEs and measured hearing decline were infrequent in both cohorts.Conclusions: In up to 20 months of ALIS use, respiratory TEAEs were common, nephrotoxicity and hearing decline were infrequent, and culture conversion continued beyond 6 months of therapy.Clinical trial registered with www.clinicaltrials.gov (NCT02628600).

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Multidrug resistance (MDR) that occurs in cancer cells constitutes one of the major reasons for chemotherapy failure. The main molecular mechanism of MDR is overexpression of protein transporters from the ATP-binding cassette (ABC) superfamily, such as ABCB1 (multidrug resistance protein 1 (MDR1), P-glycoprotein). At the expense of ATP hydrolysis, ABCB1 pumps a diverse range of substrates (including anticancer drugs) out of the cell, thereby reducing their intracellular concentration. In the present study, the ability of two patented disiloxanes (SILA-409 and SILA-421) to reverse drug resistance in human colon adenocarcinoma cell lines LoVo and LoVo/Dx was investigated. It was demonstrated that both compounds in concentrations of 0.5-1 µM strongly increased the sensitivity of LoVo/Dx cells to doxorubicin. By means of an accumulation test in which rhodamine 123 was used as an ABCB1 substrate analogue, both organosilicon compounds were also shown to inhibit ABCB1 transport activity. The intracellular accumulation of doxorubicin was also increased, and more drug entered the cellular nuclei of resistant cells in the presence of the studied compounds. In conclusion, both SILA-409 and SILA-421 were demonstrated to be effective MDR reversal agents in resistant human colon cancer cells.

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Patients with Mycobacterium avium complex lung disease treated with amikacin liposome inhalation suspension (ALIS) at 2 clinics in the United States were surveyed to assess the frequency and management of ALIS-associated respiratory adverse events. Most respondents experienced these events, but management through physician-guided measures (eg, bronchodilator use, oral rinses, and/or temporary dosing adjustments) resulted in symptomatic improvement.

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BACKGROUND: Shortcomings of inhaled antibiotic treatments for Pseudomonas aeruginosa infection in patients with cystic fibrosis (CF) include poor drug penetration, inactivation by sputum, poor efficiency due to protective biofilm, and short residence in the lung. METHODS: Eligible patients with forced expiratory volume in 1 s (FEV1) ≥25% of predicted value at screening and CF with chronic P. aeruginosa infection were randomly assigned to receive 3 treatment cycles (28 days on, 28 days off) of amikacin liposome inhalation suspension (ALIS, 590 mg QD) or tobramycin inhalation solution (TIS, 300 mg BID). The primary endpoint was noninferiority of ALIS vs TIS in change from baseline to day 168 in FEV1 (per-protocol population). Secondary endpoints included change in respiratory symptoms by Cystic Fibrosis Questionnaire-Revised (CFQ-R). RESULTS: The study was conducted February 2012 to September 2013. ALIS was noninferior to TIS (95% CI, -4.95 to 2.34) for relative change in FEV1 (L) from baseline. The mean increases in CFQ-R score from baseline on the Respiratory Symptoms scale suggested clinically meaningful improvement in both arms at the end of treatment in cycle 1 and in the ALIS arm at the end of treatment in cycles 2 and 3; however, the changes were not statistically significant between the 2 treatment arms. Treatment-emergent adverse events (TEAEs) were reported in most patients (ALIS, 84.5%; TIS, 78.8%). Serious TEAEs occurred in 17.6% and 19.9% of patients, respectively; most were hospitalisations for infective pulmonary exacerbation of CF. CONCLUSIONS: Cyclical dosing of once-daily ALIS was noninferior to cyclical twice-daily TIS in improving lung function. ClinicalTrials.gov Identifier: NCT01315678.

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Nanoparticle-induced autophagy is crucial for its metabolism, cytotoxicity and therapy potency, but little is known about how the host immune system would respond to it. In this study, we demonstrated that two clinically used superparamagnetic iron oxide nanoparticles (SPIONs) specifically induced macrophage autophagy through activation of TLR4, followed by phosphorylation of p38 and nucleus translocation of Nrf2, leading to upregulation of p62/SQSTM1 and macrophage scavenger receptor SR-AI mRNA expression. Overexpressed p62 conjugated with LC3 to form aggresome-like induced structures (ALIS) and then fused with SPIONs containing endosomes and lysosomes to form autolysosomes for degradation of endocytosed nanoparticles. More importantly, SPIONs also could promote macrophage autophagy in mouse liver which is their imaging target. We also discovered that SPIONs could stimulate the expression of inflammatory cytokines through activation of TLR4 signaling in macrophage. In general, our findings indicate that SPIONs would interact with TLR4 on the macrophage membrane and trigger its downstream signaling pathway, independent of the classic autophagic p62 reduction pathway. The observed autophagy and induced inflammatory responses in macrophages provide unique and novel perspectives in optimizing imaging/therapy nanoparticle performance in addition to analysis by traditional biochemical evaluation methods. It also enriches our understanding of NP/macrophage interaction mechanisms in reticular endothelial system (RES) organs.

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Rationale: Improved therapeutic options are needed for patients with treatment-refractory nontuberculous mycobacterial lung disease caused by Mycobacterium avium complex (MAC). Objectives: To evaluate the efficacy and safety of daily amikacin liposome inhalation suspension (ALIS) added to standard guideline-based therapy (GBT) in patients with refractory MAC lung disease. Methods: Adults with amikacin-susceptible MAC lung disease and MAC-positive sputum cultures despite at least 6 months of stable GBT were randomly assigned (2:1) to receive ALIS with GBT (ALIS + GBT) or GBT alone. Once-daily ALIS was supplied in single-use vials delivering 590 mg amikacin to the nebulizer. The primary endpoint was culture conversion, defined as three consecutive monthly MAC-negative sputum cultures by Month 6. Measurements and Main Results: Enrolled patients (ALIS + GBT, n = 224; GBT-alone, n = 112) were a mean 64.7 years old and 69.3% female. Most had underlying bronchiectasis (62.5%), chronic obstructive pulmonary disease (14.3%), or both (11.9%). Culture conversion was achieved by 65 of 224 patients (29.0%) with ALIS + GBT and 10 of 112 (8.9%) with GBT alone (odds ratio, 4.22; 95% confidence interval, 2.08-8.57; P < 0.001). Patients in the ALIS + GBT arm versus GBT alone were more likely to achieve conversion (hazard ratio, 3.90; 95% confidence interval, 2.00-7.60). Respiratory adverse events (primarily dysphonia, cough, and dyspnea) were reported in 87.4% of patients receiving ALIS + GBT and 50.0% receiving GBT alone; serious treatment-emergent adverse events occurred in 20.2% and 17.9% of patients, respectively. Conclusions: Addition of ALIS to GBT for treatment-refractory MAC lung disease achieved significantly greater culture conversion by Month 6 than GBT alone, with comparable rates of serious adverse events. Clinical trial registered with www.clinicaltrials.gov (NCT02344004).

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ALIS are large, transient, cytosolic aggregates that serve as storage compartments for ubiquitin-tagged defective ribosomal products. We determined the importance of the protein p62 in the formation of ALIS and demonstrated that two domains of p62-PB1 and UBA-are essential for ALIS assembly. Those two major binding domains of p62, also known as sequestosome 1, were shown to play a critical role in the formation of autophagosomes or cytoplasmic aggregates. Specifically, the PB1 domain is essential for self-oligomerization, and the UBA domain allows p62 to bind to polyubiquitin chains or ubiquitinated proteins. After stimulation of RAW 264.7 macrophages with lipopolysaccharide, we observed a significant decrease in the number of cells with ALIS. Importantly, cells overexpressing either a PB1 mutant or UBA-deleted p62 construct also exhibited a substantially diminished number of cells containing ALIS. Since both p62 and ubiquitin are found in ALIS, we evaluated the dynamics of YFP-tagged p62 in ALIS. In contrast to the findings of a previous study that evaluated GFP-tagged ubiquitin motility in ALIS, we determined that YFP-tagged p62 has very limited mobility. Lastly, we determined that GST-tagged full-length p62 binds to Lys-63-linked polyubiquitin chains but not to Lys-48-linked chains. Overall, our findings provide insight on the essential role that p62, particularly its PB1 and UBA domains, has in the formation of ALIS.

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Non-tuberculous mycobacteria (NTM) cause pulmonary infections in patients with structural lung damage, impaired immunity, or other risk factors. Delivering antibiotics to the sites of these infections is a major hurdle of therapy because pulmonary NTM infections can persist in biofilms or as intracellular infections within macrophages. Inhaled treatments can improve antibiotic delivery into the lungs, but efficient nebulization delivery, distribution throughout the lungs, and penetration into biofilms and macrophages are considerable challenges for this approach. Therefore, we developed amikacin liposome inhalation suspension (ALIS) to overcome these challenges. Nebulization of ALIS has been shown to provide particles within the respirable size range that distribute to both central and peripheral lung compartments in humans. The in vitro and in vivo efficacy of ALIS against NTM has been demonstrated previously. The key mechanistic questions are whether ALIS penetrates NTM biofilms and enhances amikacin uptake into macrophages. We found that ALIS effectively penetrated throughout NTM biofilms and concentration-dependently reduced the number of viable mycobacteria. Additionally, we found that ALIS improved amikacin uptake by ∼4-fold into cultured macrophages compared with free amikacin. In rats, inhaled ALIS increased amikacin concentrations in pulmonary macrophages by 5- to 8-fold at 2, 6, and 24 h post-dose and retained more amikacin at 24 h in airways and lung tissue relative to inhaled free amikacin. Compared to intravenous free amikacin, a standard-of-care therapy for refractory and severe NTM lung disease, ALIS increased the mean area under the concentration-time curve in lung tissue, airways, and macrophages by 42-, 69-, and 274-fold. These data demonstrate that ALIS effectively penetrates NTM biofilms, enhances amikacin uptake into macrophages, both in vitro and in vivo, and retains amikacin within airways and lung tissue. An ongoing Phase III trial, adding ALIS to guideline based therapy, met its primary endpoint of culture conversion by month 6. ALIS represents a promising new treatment approach for patients with refractory NTM lung disease.