Comorbid alcohol use and post-traumatic stress disorders: Pharmacotherapy with aldehyde dehydrogenase 2 inhibitors versus current agents.

The increased risk of alcohol use disorder (AUD) in individuals with post-traumatic stress disorder (PTSD) is well-documented. Compared to individuals with PTSD or AUD alone, those with co-existing PTSD and AUD exhibit greater symptom severity, poorer quality of life, and poorer treatment outcomes. Although the treatment of comorbid AUD is vital for the effective management of PTSD, there is a lack of evidence on how to best treat comorbid PTSD and AUD, and currently, there are no FDA-approved treatments for the PTSD-AUD comorbidity. The objective of this manuscript is to review the evidence of a promising target for treating the AUD-PTSD comorbidity. First, we summarize the epidemiological evidence and review the completed clinical studies that have tested pharmacotherapeutic approaches for co-existing AUD and PTSD. Next, we summarize the shared pathological factors between AUD and PTSD. We conclude by providing a rationale for selectively inhibiting aldehyde dehydrogenase-2 as a potential target to treat comorbid AUD in persons with PTSD.

Interaction of Ethanol and Oral ANS-6637, a Selective ALDH2 Inhibitor in Males: A Randomized, Double-Blind, Placebo-Controlled, Single-Ascending Dose Cohort Study.

BACKGROUND: ANS-6637, an orally bioavailable selective and reversible aldehyde dehydrogenase-2 (ALDH2) inhibitor, is under development for drug and alcohol use disorders. During the elimination of alcohol, ALDH2 metabolizes acetaldehyde to acetate; inhibiting this enzyme can lead to aversive reactions due to the accumulation of acetaldehyde. Thus, understanding the safety and tolerability of ANS-6637 in combination with alcohol is essential. TRIAL DESIGN AND METHODS: Forty eight healthy males participated in a randomized, double-blind, placebo-controlled, single-ascending dose cohort study of oral ANS-6637. Eligible participants were randomized to ANS-6637 (n = 36) or placebo (n = 12) in a 3:1 fashion in each of 6 dose cohorts (8 per cohort; ANS-6637 dose levels were 25, 50, 100, 200, 400, and 600 mg). Two hours after receiving study drug, participants drank up to 5 standard drinks, 1 every 30 minutes. Safety assessments, pharmacodynamic measures, and pharmacokinetic blood samples were obtained. RESULTS: Flushing was the most common adverse event (AE) associated with ANS-6637 (24 of 36 participants) compared with placebo (3 of 12). Statistically significant, but modest, increases in heart rate (HR) occurred (+10.5 bpm after 2 drinks; +16.9 to + 20.5 bpm after 3rd through 5th drink). No participant met HR or systolic blood pressure criteria for stopping ethanol administration. There were no clinically significant QTc interval prolongations. Individuals receiving ANS-6637 reported lower ratings of liking, alcohol effects, and feeling drunk. CONCLUSIONS: A single oral dose of ANS-6637 with up to 5 standards drinks over 2.5 hours was generally well tolerated in healthy males. The most common pharmacological response was flushing and an increase in HR, which are known effects of acetaldehyde accumulation and consistent with inhibition of ALDH2 with oral ANS-6637 in combination with alcohol. The results of this alcohol interaction study support further testing of ANS-6637 in individuals who consume alcohol heavily.

A multicenter phase II study of temozolomide plus disulfiram and copper for recurrent temozolomide-resistant glioblastoma.

PURPOSE: Preclinical studies have suggested promising activity for the combination of disulfiram and copper (DSF/Cu) against glioblastoma (GBM) including re-sensitization to temozolomide (TMZ). A previous phase I study demonstrated the safety of combining DSF/Cu with adjuvant TMZ for newly diagnosed GBM. This phase II study aimed to estimate the potential effectiveness of DSF/Cu to re-sensitize recurrent GBM to TMZ. METHODS: This open-label, single-arm phase II study treated recurrent TMZ-resistant GBM patients with standard monthly TMZ plus concurrent daily DSF 80 mg PO TID and Cu 1.5 mg PO TID. Eligible patients must have progressed after standard chemoradiotherapy and within 3 months of the last dose of TMZ. Known isocitrate dehydrogenase (IDH) mutant or secondary GBMs were excluded. The primary endpoint was objective response rate (ORR), and the secondary endpoints included progression-free survival (PFS), overall survival (OS), clinical benefit (response or stable disease for at least 6 months), and safety. RESULTS: From March 2017 to January 2018, 23 recurrent TMZ-resistant GBM patients were enrolled across seven centers, and 21 patients were evaluable for response. The median duration of DSF/Cu was 1.6 cycles (range: 0.1-12.0). The ORR was 0%, but 14% had clinical benefit. Median PFS was 1.7 months, and median OS was 7.1 months. Only one patient (4%) had dose-limiting toxicity (grade three elevated alanine transaminase). CONCLUSIONS: Addition of DSF/Cu to TMZ for TMZ-resistant IDH-wild type GBM appears well tolerated but has limited activity for unselected population.

Disulfiram-loaded mixed nanoparticles with high drug-loading and plasma stability by reducing the core crystallinity for intravenous delivery.

To develop an injectable formulation and improve the stability of disulfiram (DSF), DSF was encapsulated into mixed nanoparticles (DSF-NPs) through a high-pressure homogenization method. The Flory-Huggins interaction parameters (χFH) were calculated to predict the miscibility between DSF and the hydrophobic core, resulting in PCL5000 selected as the hydrophobic block to encapsulate the DSF, as PCL5000 had a lower χFH 3.39 and the drug loading of the nanoparticles prepared by mPEG5000-PCL5000 was relatively higher. mPEG5000-PCL5000 and PCL5000 were blended to reduce the leakage of DSF during preparation, as well as increase the stability of the nanoparticles. The cargo-loading capacity of the nanoparticles was improved from 3.35% to 5.50% by reducing the crystallinity of the PCL nanoparticle core, and the crystallinity decreased from 51.13% to 25.15% after adding medium chain triglyceride (MCT). The DSF-NPs prepared by the above method had a small particle size of 98.1 ±â€¯10.54 nm, with a polydispersity index (PDI) of 0.036, as well as drug loading of 5.50%. Furthermore, DSF-NPs containing MCT showed higher stability than DSF-NPs without MCT and DSF-sol (DSF dissolved in Cremophor EL and ethanol) in water and 90% plasma-containing PBS. The pharmacokinetics proved that DSF-NPs containing MCT enhanced the DSF concentration in the blood. Finally, DSF-NPs effectively inhibited H22 xenograft tumor growth in vivo.

In Vitro Collapsing Colon Cancer Cells by Selectivity of Disulfiram-Loaded Charge Switchable Nanoparticles Against Cancer Stem Cells.

BACKGROUND: Different strategies against colon cancer are accompanied by treatment failure, because of drug toxicity toward normal cells and cancer stem cells (CSCs) resistance. However, previous patent evaluated liposome that encapsulated inhibitor of CSCs' aldehyde dehydrogenase (ALDH)1; disulfiram, for targeting breast CSCs. Liposome has disadvantages due to its hydrophobicity. OBJECTIVES: Designing hydrophilic nanoparticles has selectivity to release disulfiram in CC cells rather than in normal colonocytes based on variation in microenvironment between normal and cancer cells. METHODS: Disulfiram was nanoformulated by its loading into cationic chitosan and coating with anionic albumin. Their selectivity and targeting were investigated using murine and human colon cancer cells compared to normal mice colon cells. RESULTS: Zeta potential of the coated nanoparticles confirmed that albumin-layering confers negative charge (-10.3mv) for disulfiram-loaded chitosan nanoparticles (52.9mv). In slightly acidic medium of tumor, the ionic bond between albumin and chitosan hydrolyzed then the positive charge was reversed (47.6mv). Thus coated nanoparticles showed higher sustain release for disulfiram in tumor microenvironment than neutral pH and their uptake was higher in cancer cells than normal cells. This interpreted the highest selectivity of coated nanoparticles for enhancing apoptosis and eliminating CSCs in cancer cells. CONCLUSION: These patented coated nanoparticles were the most effective and selective for eradicating colon CSCs without insulting normal stem cells in comparison with disulfiram which was toxic to both normal and CSCs. This novel study that used charge switchable (hydrophilic) nanoparticles for targeting colon CSCs may represent a basis for future in vivo studies.

Poly lactic-co-glycolic acid controlled delivery of disulfiram to target liver cancer stem-like cells.

Disulfiram (DS), an anti-alcoholism drug, shows very strong cytotoxicity in many cancer types. However its clinical application in cancer treatment is limited by the very short half-life in the bloodstream. In this study, we developed a poly lactic-co-glycolic acid (PLGA)-encapsulated DS protecting DS from the degradation in the bloodstream. The newly developed DS-PLGA was characterized. The DS-PLGA has very satisfactory encapsulation efficiency, drug-loading content and controlled release rate in vitro. PLGA encapsulation extended the half-life of DS from shorter than 2minutes to 7hours in serum. In combination with copper, DS-PLGA significantly inhibited the liver cancer stem cell population. CI-isobologram showed a remarkable synergistic cytotoxicity between DS-PLGA and 5-FU or sorafenib. It also demonstrated very promising anticancer efficacy and antimetastatic effect in liver cancer mouse model. Both DS and PLGA are FDA approved products for clinical application. Our study may lead to repositioning of DS into liver cancer treatment.

Stable loading and delivery of disulfiram with mPEG-PLGA/PCL mixed nanoparticles for tumor therapy.

Disulfiram (DSF) showed great potential in an in vitro tumor therapy study; however, those results could not be applied to an in vivo study due to the extreme instability of DSF in blood. Here, we describe a system of methoxy poly(ethylene glycol)-b-poly(lactide-co-glycolide)/poly(ε-caprolactone) (mPEG-PLGA/PCL) mixed nanoparticles (NPs) for DSF loading and delivery. By adjusting the mPEG-PLGA/PCL content ratios, the DSF loading capacity increased to 7.8%, while the hydrodynamic radii of the NPs were around 50-100nm. The DSF-loaded NPs showed high stability in distilled water and 10% serum-containing phosphate buffered saline. The NPs efficiently protected DSF from degradation while maintaining its anti-tumor properties. Furthermore, a pharmacokinetics study demonstrated that NP delivery system enhanced the DSF concentration in the blood after tail vein injection. Finally, DSF delivery using this model effectively slowed the growth of a 4T1 murine xenograft tumor. FROM THE CLINICAL EDITOR: The anti-tumor efficacy of the anti-alcoholic drug disulfiram has been known for some time. However, its use in the clinical setting is limited due to the underlying instability of the drug. In this study, the authors utilized a nanocarrier system of mPEG-PLGA/PCL for the delivery of this drug. The promising results may allow encapsulation of other drugs.

Disulfiram modulates stemness and metabolism of brain tumor initiating cells in atypical teratoid/rhabdoid tumors.

BACKGROUND: Atypical teratoid/rhabdoid tumors (AT/RT) are among the most malignant pediatric brain tumors. Cells from brain tumors with high aldehyde dehydrogenase (ALDH) activity have a number of characteristics that are similar to brain tumor initiating cells (BTICs). This study aimed to evaluate the therapeutic potential of ALDH inhibition using disulfiram (DSF) against BTICs from AT/RT. METHODS: Primary cultured BTICs from AT/RT were stained with Aldefluor and isolated by fluorescence activated cell sorting. The therapeutic effect of DSF against BTICs from AT/RT was confirmed in vitro and in vivo. RESULTS: AT/RT cells displayed a high expression of ALDH. DSF demonstrated a more potent cytotoxic effect on ALDH(+) AT/RT cells compared with standard anticancer agents. Notably, treatment with DSF did not have a considerable effect on normal neural stem cells or fibroblasts. DSF significantly inhibited the ALDH enzyme activity of AT/RT cells. DSF decreased self-renewal ability, cell viability, and proliferation potential and induced apoptosis and cell cycle arrest in ALDH(+) AT/RT cells. Importantly, DSF reduced the metabolism of ALDH(+) AT/RT cells by increasing the nicotinamide adenine dinucleotide ratio of NAD(+)/NADH and regulating Silent mating type Information Regulator 2 homolog 1 (SIRT1), nuclear factor-kappaB, Lin28A/B, and miRNA let-7g. Animals in the DSF-treated group demonstrated a reduction of tumor volume (P < .05) and a significant survival benefit (P = .02). CONCLUSION: Our study demonstrated the therapeutic potential of DSF against BTICs from AT/RT and suggested the possibility of ALDH inhibition for clinical application.