A Randomized, Placebo-Controlled, Pilot Clinical Trial of Dipyridamole to Decrease Human Immunodeficiency Virus-Associated Chronic Inflammation

Inflammatory and Immune Mechanisms for Atherosclerotic Cardiovascular Disease in HIV

Atherosclerotic vascular disease disproportionately affects persons living with HIV (PLWH) compared to those without. The reasons for the excess risk include dysregulated immune response and inflammation related to HIV infection itself, comorbid conditions, and co-infections. Here, we review an updated understanding of immune and inflammatory pathways underlying atherosclerosis in PLWH, including effects of viral products, soluble mediators and chemokines, innate and adaptive immune cells, and important co-infections. We also present potential therapeutic targets which may reduce cardiovascular risk in PLWH.

Inflammation in HIV and Its Impact on Atherosclerotic Cardiovascular Disease

People living with HIV have a 1.5- to 2-fold increased risk of developing cardiovascular disease. Despite treatment with highly effective antiretroviral therapy, people living with HIV have chronic inflammation that makes them susceptible to multiple comorbidities. Several factors, including the HIV reservoir, coinfections, clonal hematopoiesis of indeterminate potential (CHIP), microbial translocation, and antiretroviral therapy, may contribute to the chronic state of inflammation. Within the innate immune system, macrophages harbor latent HIV and are among the prominent immune cells present in atheroma during the progression of atherosclerosis. They secrete inflammatory cytokines such as IL (interleukin)-6 and tumor necrosis-α that stimulate the expression of adhesion molecules on the endothelium. This leads to the recruitment of other immune cells, including cluster of differentiation (CD)8+ and CD4+ T cells, also present in early and late atheroma. As such, cells of the innate and adaptive immune systems contribute to both systemic inflammation and vascular inflammation. On a molecular level, HIV-1 primes the NLRP3 (NLR family pyrin domain containing 3) inflammasome, leading to an increased expression of IL-1β, which is important for cardiovascular outcomes. Moreover, activation of TLRs (toll-like receptors) by HIV, gut microbes, and substance abuse further activates the NLRP3 inflammasome pathway. Finally, HIV proteins such as Nef (negative regulatory factor) can inhibit cholesterol efflux in monocytes and macrophages through direct action on the cholesterol transporter ABCA1 (ATP-binding cassette transporter A1), which promotes the formation of foam cells and the progression of atherosclerotic plaque. Here, we summarize the stages of atherosclerosis in the context of HIV, highlighting the effects of HIV, coinfections, and antiretroviral therapy on cells of the innate and adaptive immune system and describe current and future interventions to reduce residual inflammation and improve cardiovascular outcomes among people living with HIV.

The combination of pleconaril, rupintrivir, and remdesivir efficiently inhibits enterovirus infections in vitro, delaying the development of drug-resistant virus variants

Enteroviruses are a significant global health concern, causing a spectrum of diseases from the common cold to more severe conditions like hand-foot-and-mouth disease, meningitis, myocarditis, pancreatitis, and poliomyelitis. Current treatment options for these infections are limited, underscoring the urgent need for effective therapeutic strategies. To find better treatment option we analyzed toxicity and efficacy of 12 known broad-spectrum anti-enterovirals both individually and in combinations against different enteroviruses in vitro. We identified several novel, synergistic two-drug and three-drug combinations that demonstrated significant inhibition of enterovirus infections in vitro. Specifically, the triple-drug combination of pleconaril, rupintrivir, and remdesivir exhibited remarkable efficacy against echovirus (EV) 1, EV6, EV11, and coxsackievirus (CV) B5, in human lung epithelial A549 cells. This combination surpassed the effectiveness of single-agent or dual-drug treatments, as evidenced by its ability to protect A549 cells from EV1-induced cytotoxicity across seven passages. Additionally, this triple-drug cocktail showed potent antiviral activity against EV-A71 in human intestinal organoids. Thus, our findings highlight the therapeutic potential of the pleconaril-rupintrivir-remdesivir combination as a broad-spectrum treatment option against a range of enterovirus infections. The study also paves the way towards development of strategic antiviral drug combinations with virus family coverage and high-resistance barriers.

Potential for modulation of platelet function via adenosine receptors during inflammation

Traditionally, platelets are known to play an important role in haemostasis and thrombosis; however, they serve also as important modulators of inflammation and immunity. Platelets secrete adhesion molecules and cytokines, interact with leukocytes and endothelium, and express toll-like receptors involved in a direct interaction with pathogens. Platelets express A2A and A2B subtypes of receptors for adenosine. The activation of these receptors leads to an increase in cAMP concentration in the cytoplasm, thereby resulting in inhibited secretion of pro-inflammatory mediators and reduced cell activation. Therefore, platelet adenosine receptors could be a potential target for inhibiting platelet activation and thus down-regulating inflammation or immunity. The biological effects of adenosine are short-lasting, because the compound is rapidly metabolized; hence, its lability has triggered efforts to synthesize new, longer-lasting adenosine analogues. In this article, we have reviewed the literature regarding the pharmacological potential of adenosine and other agonists of A2A and A2B receptors to affect platelet function during inflammation. LINKED ARTICLES: This article is part of a themed issue on Platelet purinergic receptor and non-thrombotic disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.4/issuetoc.

Drugs targeting adenosine signaling pathways: A current view

Adenosine is an endogenous nucleoside that regulates many physiological and pathological processes. It is derived from either the intracellular or extracellular dephosphorylation of adenosine triphosphate and interacts with cell-surface G-protein-coupled receptors. Adenosine plays a substantial role in protecting against cell damage in areas of increased tissue metabolism and preventing organ dysfunction in pathological states. Targeting adenosine metabolism and receptor signaling may be an effective therapeutic approach for human diseases, including cardiovascular and central nervous system disorders, rheumatoid arthritis, asthma, renal diseases, and cancer. Several lines of evidence have shown that many drugs exert their beneficial effects by modulating adenosine signaling pathways but this knowledge urgently needs to be summarized, and most importantly, actualized. The present review collects pharmaceuticals and pharmacological or diagnostic tools that target adenosine signaling in their primary or secondary mode of action. We overviewed FDA-approved drugs as well as those currently being studied in clinical trials. Among them are already used in clinic A2A adenosine receptor modulators like istradefylline or regadenoson, but also plenty of anti-platelet, anti-inflammatory, or immunosuppressive, and anti-cancer drugs. On the other hand, we investigated dozens of specific adenosine pathway regulators that are tested in clinical trials to treat human infectious and noninfectious diseases. In conclusion, targeting purinergic signaling represents a great therapeutic challenge. The actual knowledge of the involvement of adenosinergic signaling as part of the mechanism of action of old drugs has open a path not only for drug-repurposing but also for new therapeutic strategies.

A Systematic Review of the Role of Purinergic Signalling Pathway in the Treatment of COVID-19

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global health concern. Three years since its origin, despite the approval of vaccines and specific treatments against this new coronavirus, there are still high rates of infection, hospitalization, and mortality in some countries. COVID-19 is characterised by a high inflammatory state and coagulation disturbances that may be linked to purinergic signalling molecules such as adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine (ADO), and purinergic receptors (P1 and P2). These nucleotides/nucleosides play important roles in cellular processes, such as immunomodulation, blood clot formation, and vasodilation, which are affected during SARS-CoV-2 infection. Therefore, drugs targeting this purinergic pathway, currently used for other pathologies, are being evaluated in preclinical and clinical trials for COVID-19. In this review, we focus on the potential of these drugs to control the release, degradation, and reuptake of these extracellular nucleotides and nucleosides to treat COVID-19. Drugs targeting the P1 receptors could have therapeutic efficacy due to their capacity to modulate the cytokine storm and the immune response. Those acting in P2X7, which is linked to NLRP3 inflammasome activation, are also valuable candidates as they can reduce the release of pro-inflammatory cytokines. However, according to the available preclinical and clinical data, the most promising medications to be used for COVID-19 treatment are those that modulate platelets behaviour and blood coagulation factors, mainly through the P2Y12 receptor.

The Many Faces of Immune Activation in HIV-1 Infection: A Multifactorial Interconnection

Chronic immune activation has a significant role in HIV-1 disease pathogenesis and CD4+ T-cell depletion. The causes of chronic inflammation and immune activation are incompletely understood, but they are likely multifactorial in nature, involving both direct and indirect stimuli. Possible explanations include microbial translocation, coinfection, and continued presence of competent replicating virus. In fact, long-term viral suppression treatments are unable to normalize elevated markers of systemic immune activation. Furthermore, high levels of pro-inflammatory cytokines increase susceptibility to premature aging of the immune system. The phenomenon of "inflammaging" has begun to be evident in the last decades, as a consequence of increased life expectancy due to the introduction of cART. Quality of life and survival have improved substantially; however, PLWH are predisposed to chronic inflammatory conditions leading to age-associated diseases, such as inflammatory bowel disease, neurocognitive disorders, cardiovascular diseases, metabolic syndrome, bone abnormalities, and non-HIV-associated cancers. Several approaches have been studied in numerous uncontrolled and/or randomized clinical trials with the aim of reducing immune activation/inflammatory status in PLWH, none of which have achieved consistent results.

Suppressed renoprotective purines in COVID-19 patients with acute kidney injury

Acute kidney injury (AKI) is common in patients hospitalized for COVID-19, complicating their clinical course and contributing to worse outcomes. Animal studies show that adenosine, inosine and guanosine protect the kidney against some types of AKI. However, until now there was no evidence in patients supporting the possibility that abnormally low kidney levels of adenosine, inosine and guanosine contribute to AKI. Here, we addressed the question as to whether these renoprotective purines are altered in the urine of COVID-19 patients with AKI. Purines were measured by employing ultra-high-performance liquid chromatography-tandem mass spectrometry with stable-isotope-labeled internal standards for each purine of interest. Compared with COVID-19 patients without AKI (n = 23), COVID-19 patients with AKI (n = 20) had significantly lower urine levels of adenosine (P < 0.0001), inosine (P = 0.0008), and guanosine (P = 0.0008) (medians reduced by 85%, 48% and 61%, respectively) and lower levels (P = 0.0003; median reduced by 67%) of the 2nd messenger for A2A and A2B adenosine receptors, i.e., 3',5'-cAMP. Moreover, in COVID-19 patients with AKI, urine levels of 8-aminoguanine (endogenous inhibitor of inosine and guanosine metabolism) were nearly abolished (P < 0.0001). In contrast, the "upstream" precursors of renoprotective purines, namely 5'-AMP and 5'-GMP, were not significantly altered in COVID-19 patients with AKI, suggesting defective conversion of these precursors by CD73 (converts 5'-AMP to adenosine and 5'-GMP to guanosine). These findings imply that an imbalance in renoprotective purines may contribute to AKI in COVID-19 patients and that pharmacotherapy targeted to restore levels of renoprotective purines may attenuate the risk of AKI in susceptible patients with COVID-19.

Neuroinflammation and Neuropathology

This review addresses the current understanding of the role of autoimmune neuroinflammation in the pathogenesis of vascular, neurodegenerative, and other diseases of the nervous system. The mechanisms of responses of resident CNS cells (glial cells, astrocytes) and peripheral immune system cells are presented. The therapeutic potentials of phosphodiesterase inhibitors, which have antiaggregant properties and can suppress autoimmune inflammation, are discussed. The phosphodiesterase inhibitor dipyridamole is regarded as a potential drug for this purpose.

Purinergic receptor ligands: the cytokine storm attenuators, potential therapeutic agents for the treatment of COVID-19

The coronavirus disease-19 (COVID-19), at first, was reported in Wuhan, China, and then rapidly became pandemic throughout the world. Cytokine storm syndrome (CSS) in COVID-19 patients is associated with high levels of cytokines and chemokines that cause multiple organ failure, systemic inflammation, and hemodynamic instabilities. Acute respiratory distress syndrome (ARDS), a common complication of COVID-19, is a consequence of cytokine storm. In this regard, several drugs have been being investigated to suppress this inflammatory condition. Purinergic signaling receptors comprising of P1 adenosine and P2 purinoceptors play a critical role in inflammation. Therefore, activation or inhibition of some subtypes of these kinds of receptors is most likely to be beneficial to attenuate cytokine storm. This article summarizes suggested therapeutic drugs with potential anti-inflammatory effects through purinergic receptors.

HIV-Related Immune Activation and Inflammation: Current Understanding and Strategies

Although antiretroviral therapy effectively controls human immunodeficiency virus (HIV) replication, a residual chronic immune activation/inflammation persists throughout the disease. This aberrant immune activation and inflammation are considered an accelerator of non-AIDS-related events and one of the driving forces of CD4⁺ T cell depletion. Unfortunately, HIV-associated immune activation is driven by various factors, while the mechanism of excessive inflammation has not been formally clarified. To date, several clinical interventions or treatment candidates undergoing clinical trials have been proposed to combat this systemic immune activation/inflammation. However, these strategies revealed limited results, or their nonspecific anti-inflammatory properties are similar to previous interventions. Here, we reviewed recent learnings of immune activation and persisting inflammation associated with HIV infection, as well as the current directions to overcome it. Of note, a more profound understanding of the specific mechanisms for aberrant inflammation is still imperative for identifying an effective clinical intervention strategy.

The Adenosine Pathway and Human Immunodeficiency Virus-Associated Inflammation

Human immunodeficiency virus (HIV) is associated with an increased risk of age-associated comorbidities and mortality compared to people without HIV. This has been attributed to HIV-associated chronic inflammation and immune activation despite viral suppression. The adenosine pathway is an established mechanism by which the body regulates persistent inflammation to limit tissue damage associated with inflammatory conditions. However, HIV infection is associated with derangements in the adenosine pathway that limits its ability to control HIV-associated inflammation. This article reviews the function of purinergic signaling and the role of the adenosine signaling pathway in HIV-associated chronic inflammation. This review also discusses the beneficial and potential detrimental effects of pharmacotherapeutic strategies targeting this pathway among people with HIV.

[Diabetic encephalopathy: current insights and potential therapeutic strategies]

OBJECTIVE

To study the effect of alpha-lipoic acid (ALA) on cognitive functions in patients with non-insulin dependent diabetes mellitus type 2 (DM-2) and thick fiber polyneuropathy.

MATERIAL AND METHODS

The MoCA test was used to assess cognitive functions, and vibrometry («Somedic» vibrometer) was used to assess the function of thick fibers. Patients in group 1 (n=37) received alpha lipoic acid (ALA) in a dose of 600 mg per day for 16 weeks, patients in group 2 (n=41) started taking ALA 8 weeks after the start of the study.

RESULTS

Comparison of both groups showed an increase in the indicators of the MoCA test in group 1 after 8 weeks (p=0.0025) with a further plateau and an improvement in vibration sensitivity after 16 weeks (p=0.023). The improvement in the MoCA test in group 2 also began after 8 weeks.

CONCLUSION

The authors recommend ALA in polyneuropathy as a drug that also has a positive effect on cognitive functions in DM-2 and dipyridamole for the treatment of patients with diabetic encephalopathy and cerebral small vessels disease and stroke.

[Neuroinflammation and neuropathology]

The review highlights the current understanding of the role of autoimmune neuroinflammation in the pathogenesis of vascular, neurodegenerative and other diseases of the nervous system. The mechanisms of the response of the resident cells of the central nervous system (microglia, astrocytes) and peripheral cells of the immune system are considered. Possible therapeutic potential of phosphodiesterase inhibitors, which have antiplatelet properties and the ability to suppress autoimmune inflammation, are outlined. The authors consider dipyridamole, an inhibitor of phosphodiesterase, as a promising drug.

Gut Leakage of Fungal-Related Products: Turning Up the Heat for HIV Infection

The intestinal epithelial layer serves as a physical and functional barrier between the microbiota in the lumen and immunologically active submucosa. Th17 T-cell function protects the gut epithelium from aggression from microbes and their by-products. Loss of barrier function has been associated with enhanced translocation of microbial products which act as endotoxins, leading to local and systemic immune activation. Whereas the inflammatory role of LPS produced by Gram-negative bacteria has been extensively studied, the role of fungal products such as β-D-glucan remains only partially understood. As HIV infection is characterized by impaired gut Th17 function and increased gut permeability, we critically review mechanisms of immune activation related to fungal translocation in this viral infection. Additionally, we discuss markers of fungal translocation for diagnosis and monitoring of experimental treatment responses. Targeting gut barrier dysfunction and reducing fungal translocation are emerging strategies for the prevention and treatment of HIV-associated inflammation and may prove useful in other inflammatory chronic diseases.

Brief Report: Dipyridamole Decreases Gut Mucosal Regulatory T-Cell Frequencies Among People With HIV on Antiretroviral Therapy

BACKGROUND

We had previously conducted a double-blind, randomized placebo-controlled, partial cross-over trial showing that 12 weeks of dipyridamole decreased CD8 T-cell activation among treated HIV(+) individuals by increasing extracellular adenosine levels.

METHODS

In this substudy, rectosigmoid biopsies were obtained from 18 participants (9 per arm), to determine whether 12 weeks of dipyridamole affects mucosal immune cells. Participants randomized to placebo were then switched to dipyridamole for 12 weeks while the treatment arm continued dipyridamole for another 12 weeks. We evaluated T-cell frequencies and plasma markers of microbial translocation and intestinal epithelial integrity. Linear regression models on log-transformed outcomes were used for the primary 12-week analysis.

RESULTS

Participants receiving dipyridamole had a median 70.2% decrease from baseline in regulatory T cells (P = 0.007) and an 11.3% increase in CD8 T cells (P = 0.05). There was a nonsignificant 10.80% decrease in plasma intestinal fatty acid binding protein levels in the dipyridamole arm compared with a 9.51% increase in the placebo arm. There were no significant differences in plasma levels of β-D-glucan. In pooled analyses, there continued to be a significant decrease in regulatory T cells (-44%; P = 0.004). There was also a trend for decreased CD4 and CD8 T-cell activation.

CONCLUSION

Increasing extracellular adenosine levels using dipyridamole in virally suppressed HIV (+) individuals on antiretroviral therapy can affect regulation of gut mucosal immunity.

Inflammatory pathways and potential therapies for COVID-19: A mini review

The public health crisis of the novel coronavirus disease (COVID-19) is alarming since January 2020. COVID-19 genome (SARS-CoV-2) is related to other highly pathogenic coronaviruses SARS-CoV (severe acute respiratory syndrome coronavirus) and MERS-CoV (Middle East respiratory syndrome coronavirus). Amino acid substitutions in some of SARS-CoV-2 proteins resulted in mutations proposing more virulent and contagious properties for this novel virus. Coronavirus penetrates the host cell via endocytosis and once infected, immune responses are triggered to fight against the pathogen. Innate immune response activates major transcription factors to secrete proinflammatory cytokines and type 1 interferon response (T1INF) to induce antiviral immunity. While adaptive immunity initiates cascade of B-cells antibody mediated and T-cells cellular mediate immunities, several mechanisms are raised by SARS-CoV-2 to evade host immune response. Consequently, a surge of proinflammatory cytokines, known as cytokine storm (CS) are released. Failure to manage CS results in several pathological complications as acute respiratory distress syndrome (ARDS). Although researches have not discovered an effective treatment against SARS-CoV-2, recent therapeutic approaches recommending the use of anti-inflammatories in combination with antivirals and some repurposed drugs for COVID-19 patients. Future medications should be designed to target essential hallmarks in the CS to improve clinical outcomes.

Adjunct Therapy for CD4+ T-Cell Recovery, Inflammation and Immune Activation in People Living With HIV: A Systematic Review and Meta-Analysis

Background: HIV infection results in immune homeostasis perturbations, which is characterized by CD4⁺ T-cell depletion, immune activation, and inflammation. Effective antiretroviral therapy (ART) does not fully restore immunologic and clinical health in people living with HIV (PLWH). Various drugs have been used to improve their immune status and CD4⁺ T-cell counts, but no measures have been tested effective. Here we conduct a systematic review and meta-analysis of existing clinical studies on improving CD4⁺ T-cell count while decreasing inflammation and immune activation.

Methods: We retrieved possible relevant publications from a total of five electronic databases and selected eligible studies, which dealt with outcomes of medical therapy for CD4⁺ T-cell count recovery, inflammation, and immune activation with or without ART. We paid particular attention to immunologic non-responders with a favorable treatment regimen.

Results: Thirty-three articles were included in the systematic review and meta-analysis. However, there were no safe and effective medications specific for improving CD4⁺ T-cell reconstitution. The immunological benefits or adverse events mainly depend on the safety, dosage, and duration of the candidate medication use, as well as whether it is combined with ART.

Conclusion: Under the “safe, combined, adequate and long (SCAL)” principles, alternative approaches are needed to accelerate the recovery of CD4⁺ T-cells, and to prevent adverse long-term outcomes in PLWH with standard ART treatment.

Imaging modalities for cardiovascular phenotyping in asymptomatic people living with HIV

Cardiovascular disease (CVD) has emerged as a leading cause of non-HIV-related mortality among people living with HIV (PLWH). Despite the growing CVD burden in PLWH, there is concern that general population risk score models may underestimate CVD risk in these patients. Imaging modalities have received mounting attention lately to better understand the pathophysiology of subclinical CVD and provide improved risk assessment in this population. To date, traditional and well-established techniques such as echocardiography, pulse wave velocity, and carotid intima thickness continue to be the basis for the diagnosis and subsequent monitoring of vascular atherosclerosis and heart failure. Furthermore, novel imaging tools such as cardiac computed tomography (CT) and cardiac CT angiography (CCTA), positron emission tomography/CT (PET/CT), and cardiac magnetic resonance (CMR) have provided new insights into accelerated cardiovascular abnormalities in PLWH and are currently evaluated with regards to their potential to improve risk stratification.

Potential Therapeutic Benefits of Dipyridamole in COVID-19 Patients

BACKGROUND

COVID-19 pandemic is caused by coronavirus also known as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The viral infection continues to impact the globe with no vaccine to prevent the infection or highly effective therapeutics to treat the millions of infected people around the world. The disease starts as a respiratory infection, yet it may also be associated with a hypercoagulable state, severe inflammation owing to excessive cytokines production, and a potentially significant oxidative stress. The disease may progress to multiorgan failure and eventually death.

OBJECTIVE

In this article, we summarize the potential of dipyridamole as an adjunct therapy for COVID-19.

METHODS

We reviewed the literature describing the biological activities of dipyridamole in various settings of testing. Data were retrieved from PubMed, SciFinder-CAS, and Web of Science. The review concisely covered relevant studies starting from 1977.

RESULTS

Dipyridamole is an approved antiplatelet drug, that has been used to prevent stroke, among other indications. Besides its antithrombotic activity, the literature indicates that dipyridamole also promotes a host of other biological activities including antiviral, anti-inflammatory, and antioxidant ones.

CONCLUSION

Dipyridamole may substantially help improve the clinical outcomes of COVID-19 treatment. The pharmacokinetics profile of the drug is well established which makes it easier to design an appropriate therapeutic course. The drug is also generally safe, affordable, and available worldwide. Initial clinical trials have shown a substantial promise for dipyridamole in treating critically ill COVID-19 patients, yet larger randomized and controlled trials are needed to confirm this promise.

COVID-19-associated coagulopathy: An exploration of mechanisms

An ongoing global pandemic of viral pneumonia (coronavirus disease [COVID-19]), due to the virus SARS-CoV-2, has infected millions of people and remains a threat to many more. Most critically ill patients have respiratory failure and there is an international effort to understand mechanisms and predictors of disease severity. Coagulopathy, characterized by elevations in D-dimer and fibrin(ogen) degradation products (FDPs), is associated with critical illness and mortality in patients with COVID-19. Furthermore, increasing reports of microvascular and macrovascular thrombi suggest that hemostatic imbalances may contribute to the pathophysiology of SARS-CoV-2 infection. We review the laboratory and clinical findings of patients with COVID-19-associated coagulopathy, and prior studies of hemostasis in other viral infections and acute respiratory distress syndrome. We hypothesize that an imbalance between coagulation and inflammation may result in a hypercoagulable state. Although thrombosis initiated by the innate immune system is hypothesized to limit SARS-CoV-2 dissemination, aberrant activation of this system can cause endothelial injury resulting in loss of thromboprotective mechanisms, excess thrombin generation, and dysregulation of fibrinolysis and thrombosis. The role various components including neutrophils, neutrophil extracellular traps, activated platelets, microparticles, clotting factors, inflammatory cytokines, and complement play in this process remains an area of active investigation and ongoing clinical trials target these different pathways in COVID-19.

NLRP3 Inflammasome Signaling as a Link Between HIV-1 Infection and Atherosclerotic Cardiovascular Disease

36.9 million people worldwide are living with HIV-1. The disease remains incurable and HIV-infected patients have increased risk of atherosclerosis. Inflammation is a key driver of atherosclerosis, but no targeted molecular therapies have been developed to reduce cardiovascular risk in people with HIV-1 (PWH). While the mechanism is unknown, there are several important inflammatory signaling events that are implicated in the development of chronic inflammation in PWH and in the inflammatory changes that lead to atherosclerosis. Here we describe the pro-inflammatory state of HIV-1 infection that leads to increased risk of cardiovascular disease, the role of the NLR Family Pyrin Domain Containing 3 (NLRP3) inflammasome in HIV-1 infection, the role of the NLRP3 inflammasome in cardiovascular disease (CVD), and outline a model whereby HIV-1 infection can lead to atherosclerotic disease through NLRP3 inflammasome activation. Our discussion highlights the literature supporting HIV-1 infection as a stimulator of the NLRP3 inflammasome as a driver of atherosclerosis.

Delivering Benefits at Speed Through Real-World Repurposing of Off-Patent Drugs: The COVID-19 Pandemic as a Case in Point

Real-world drug repurposing-the immediate "off-label" prescribing of drugs to address urgent clinical needs-is a widely overlooked opportunity. Off-label prescribing (ie, for a nonapproved indication) is legal in most countries and tends to shift the burden of liability and cost to physicians and patients, respectively. Nevertheless, health crises may mean that real-world repurposing is the only realistic source for solutions. Optimal real-world repurposing requires a track record of safety, affordability, and access for drug candidates. Although thousands of such drugs are already available, there is no central repository of off-label uses to facilitate immediate identification and selection of potentially useful interventions during public health crises. Using the current coronavirus disease (COVID-19) pandemic as an example, we provide a glimpse of the extensive literature that supports the rationale behind six generic drugs, in four classes, all of which are affordable, supported by decades of safety data, and targeted toward the underlying pathophysiology that makes COVID-19 so deadly. This paper briefly summarizes why cimetidine or famotidine, dipyridamole, fenofibrate or bezafibrate, and sildenafil citrate are worth considering for patients with COVID-19. Clinical trials to assess efficacy are already underway for famotidine, dipyridamole, and sildenafil, and further trials of all these agents will be important in due course. These examples also reveal the unlimited opportunity to future-proof our health care systems by proactively mining, synthesizing, cataloging, and evaluating the off-label treatment opportunities of thousands of safe, well-established, and affordable generic drugs.

No Time to Waste: Real-World Repurposing of Generic Drugs as a Multifaceted Strategy Against COVID-19

Real-world drug repurposing-the immediate "off-label" prescribing of drugs to address urgent clinical needs-is an indispensable strategy gaining rapid traction in the current COVID-19 crisis. Although off-label prescribing (ie, for a nonapproved indication) is legal in most countries, it tends to shift the burden of liability and cost to physicians and patients, respectively. Nevertheless, in urgent public health crises, it is often the only realistic source of a meaningful potential solution. To be considered for real-world repurposing, drug candidates should ideally have a track record of safety, affordability, and wide accessibility. Although thousands of such drugs are already available, the absence of a central repository of off-label uses presents a barrier to the immediate identification and selection of the safest, potentially useful interventions. Using the current COVID-19 pandemic as an example, we provide a glimpse at the extensive literature that supports the rationale behind six generic drugs, in four classes, all of which are affordable, supported by decades of safety data, and pleiotropically target the underlying pathophysiology that makes COVID-19 so dangerous. Having previously fast-tracked this paper to publication in summary form, we now expand on why cimetidine/famotidine (histamine type-2 receptor antagonists), dipyridamole (antiplatelet agent), fenofibrate/bezafibrate (cholesterol/triglyceride-lowering agents), and sildenafil (phosphodiesterase-5 inhibitor) are worth considering for patients with COVID-19 based on their antiviral, anti-inflammatory, renoprotective, cardioprotective, and anticoagulation properties. These examples also reveal the unlimited opportunity to future-proof public health by proactively mining, synthesizing, and cataloging the off-label treatment opportunities of thousands of safe, well-established, and affordable generic drugs.