Effect of disease duration in a randomized Phase III trial of rintatolimod, an immune modulator for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

BACKGROUND: Rintatolimod is a selective TLR3 agonist, which has demonstrated clinical activity for ME/CFS in Phase II and Phase III double-blind, placebo-controlled, randomized, multi-site clinical trials. METHODS AND FINDINGS: A hypothesis-based post-hoc analysis of the Intent to Treat (ITT) population diagnosed with ME/CFS from 12 independent clinical sites of a Phase III trial was performed to evaluate the effect of rintatolimod therapy based on disease duration. The clinical activity of rintatolimod was evaluated by exercise treadmill tolerance (ETT) using a modified Bruce protocol. The ITT population (n = 208) was divided into two subsets of symptom duration. Patients with symptom duration of 2-8 years were identified as the Target Subset (n = 75); the remainder (<2 year plus >8 year) were identified as the Non-Target Subset (n = 133). Placebo-adjusted percentage improvements in exercise duration and the vertical rise for the Target Subset (n = 75) were more than twice that of the ITT population. The Non-Target Subset (n = 133) failed to show any clinically significant ETT response to rintatolimod when compared to placebo. Within the Target Subset, 51.2% of rintatolimod-treated patients improved their exercise duration by ≥25% (p = 0.003) despite reduced statistical power from division of the original ITT population into two subsets. CONCLUSION/SIGNIFICANCE: Analysis of ETT from a Phase III trial has identified within the ITT population, a subset of ME/CFS patients with ≥2 fold increased exercise response to rintatolimod. Substantial improvement in physical performance was seen for the majority (51.2%) of these severely debilitated patients who improved exercise duration by ≥25%. This magnitude of exercise improvement was associated with clinically significant enhancements in quality of life. The data indicate that ME/CFS patients have a relatively short disease duration window (<8 years) to expect a significant response to rintatolimod under the dosing conditions utilized in this Phase III clinical trial. These results may have direct relevance to the cognitive impairment and fatigue being experienced by patients clinically recovered from COVID-19 and free of detectable SARS-CoV-2. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00215800.

Leveraging Prior Knowledge of Endocrine Immune Regulation in the Therapeutically Relevant Phenotyping of Women With Chronic Fatigue Syndrome.

PURPOSE: The complex and varied presentation of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) has made it difficult to diagnose, study, and treat. Its symptoms and likely etiology involve multiple components of endocrine and immune regulation, including the hypothalamic-pituitary-adrenal axis, the hypothalamic-pituitary-gonadal axis, and their interactive oversight of immune function. We propose that the persistence of ME/CFS may involve changes in the regulatory interactions across these physiological axes. We also propose that the robustness of this new pathogenic equilibrium may at least in part explain the limited success of conventional single-target therapies. METHODS: A comprehensive model was constructed of female endocrine-immune signaling consisting of 28 markers linked by 214 documented regulatory interactions. This detailed model was then constrained to adhere to experimental measurements in a subset of 17 candidate immune markers measured in peripheral blood of patients with ME/CFS and healthy control subjects before, during, and after a maximal exercise challenge. A set of 26 competing numerical models satisfied these data to within 5% error. FINDINGS: Mechanistically informed predictions of endocrine and immune markers that were either unmeasured or exhibited high subject-to-subject variability pointed to possible context-specific overexpression in ME/CFS at rest of corticotropin-releasing hormone, chemokine (C-X-C motif) ligand 8, estrogen, follicle-stimulating hormone (FSH), gonadotropin-releasing hormone 1, interleukin (IL)-23, and luteinizing hormone, and underexpression of adrenocorticotropic hormone, cortisol, interferon-γ, IL-10, IL-17, and IL-1α. Simulations of rintatolimod and rituximab treatment predicted a shift in the repertoire of available endocrine-immune regulatory regimens. Rintatolimod was predicted to make available substantial remission in a significant subset of subjects, in particular those with low levels of IL-1α, IL-17, and cortisol; intermediate levels of progesterone and FSH; and high estrogen levels. Rituximab treatment was predicted to support partial remission in a smaller subset of patients with ME/CFS, specifically those with low norepinephrine, IL-1α, chemokine (C-X-C motif) ligand 8, and cortisol levels; intermediate FSH and gonadotropin-releasing hormone 1 levels; and elevated expression of tumor necrosis factor-α, luteinizing hormone, IL-12, and B-cell activation. IMPLICATIONS: Applying a rigorous filter of known signaling mechanisms to experimentally measured immune marker expression in ME/CFS has highlighted potential new context-specific markers of illness. These novel endocrine and immune markers may offer useful candidates in delineating new subtypes of ME/CFS and may inform on refinements to the inclusion criteria and instrumentation of new and ongoing trials involving rintatolimod and rituximab treatment protocols.

Treatment and management of chronic fatigue syndrome/myalgic encephalomyelitis: all roads lead to Rome.

This review explores the current evidence on benefits and harms of therapeutic interventions in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) and makes recommendations. CFS/ME is a complex, multi-system, chronic medical condition whose pathophysiology remains unknown. No established diagnostic tests exist nor are any FDA-approved drugs available for treatment. Because of the range of symptoms of CFS/ME, treatment approaches vary widely. Studies undertaken have heterogeneous designs and are limited by sample size, length of follow-up, applicability and methodological quality. The use of rintatolimod and rituximab as well as counselling, behavioural and rehabilitation therapy programs may be of benefit for CFS/ME, but the evidence of their effectiveness is still limited. Similarly, adaptive pacing appears to offer some benefits, but the results are debatable: so is the use of nutritional supplements, which may be of value to CFS/ME patients with biochemically proven deficiencies. To summarize, the recommended treatment strategies should include proper administration of nutritional supplements in CFS/ME patients with demonstrated deficiencies and personalized pacing programs to relieve symptoms and improve performance of daily activities, but a larger randomized controlled trial (RCT) evaluation is required to confirm these preliminary observations. At present, no firm conclusions can be drawn because the few RCTs undertaken to date have been small-scale, with a high risk of bias, and have used different case definitions. Further, RCTs are now urgently needed with rigorous experimental designs and appropriate data analysis, focusing particularly on the comparison of outcomes measures according to clinical presentation, patient characteristics, case criteria and degree of disability (i.e. severely ill ME cases or bedridden).

Efficacy of rintatolimod in the treatment of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME).

Chronic fatigue syndrome/ Myalgic encephalomyelitis (CFS/ME) is a poorly understood seriously debilitating disorder in which disabling fatigue is an universal symptom in combination with a variety of variable symptoms. The only drug in advanced clinical development is rintatolimod, a mismatched double stranded polymer of RNA (dsRNA). Rintatolimod is a restricted Toll-Like Receptor 3 (TLR3) agonist lacking activation of other primary cellular inducers of innate immunity (e.g.- cytosolic helicases). Rintatolimod also activates interferon induced proteins that require dsRNA for activity (e.g.- 2'-5' adenylate synthetase, protein kinase R). Rintatolimod has achieved statistically significant improvements in primary endpoints in Phase II and Phase III double-blind, randomized, placebo-controlled clinical trials with a generally well tolerated safety profile and supported by open-label trials in the United States and Europe. The chemistry, mechanism of action, clinical trial data, and current regulatory status of rintatolimod for CFS/ME including current evidence for etiology of the syndrome are reviewed.

Treatment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Systematic Review for a National Institutes of Health Pathways to Prevention Workshop.

BACKGROUND: Myalgic encephalomyelitis (ME)/chronic fatigue syndrome (CFS) is a debilitating multisystem condition affecting more than 1 million adults in the United States. PURPOSE: To determine benefits and harms of treatments for adults with ME/CFS and identify future research needs. DATA SOURCES: MEDLINE, PsycINFO, and Cochrane databases (January 1988 to September 2014); clinical trial registries; reference lists; and manufacturer information. STUDY SELECTION: English-language randomized trials of the effectiveness and adverse effects of ME/CFS treatments. DATA EXTRACTION: Data on participants, study design, analysis, follow-up, and results were extracted and confirmed. Study quality was dual-rated by using prespecified criteria; discrepancies were resolved through consensus. DATA SYNTHESIS: Among 35 treatment trials enrolling participants primarily meeting the 1994 Centers for Disease Control and Prevention and Oxford case definitions of CFS, the immune modulator rintatolimod improved some measures of exercise performance compared with placebo in 2 trials (low strength of evidence). Trials of galantamine, hydrocortisone, IgG, valganciclovir, isoprinosine, fluoxetine, and various complementary medicines were inconclusive (insufficient evidence). Counseling therapies and graded exercise therapy compared with no treatment, relaxation, or support improved fatigue, function, global improvement, and work impairment in some trials; counseling therapies also improved quality of life (low to moderate strength of evidence). Harms were rarely reported across studies (insufficient evidence). LIMITATION: Trials were heterogeneous and were limited by size, number, duration, applicability, and methodological quality. CONCLUSION: Trials of rintatolimod, counseling therapies, and graded exercise therapy suggest benefit for some patients meeting case definitions for CFS, whereas evidence for other treatments and harms is insufficient. More definitive studies comparing participants meeting different case definitions, including ME, and providing subgroup analysis are needed to fill research gaps.

A double-blind, placebo-controlled, randomized, clinical trial of the TLR-3 agonist rintatolimod in severe cases of chronic fatigue syndrome.

BACKGROUND: Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a severely debilitating disease of unknown pathogenesis consisting of a variety of symptoms including severe fatigue. The objective of the study was to examine the efficacy and safety of a TLR-3 agonist, rintatolimod (Poly I: C(12)U), in patients with debilitating CFS/ME. METHODS AND FINDINGS: A Phase III prospective, double-blind, randomized, placebo-controlled trial comparing twice weekly IV rintatolimod versus placebo was conducted in 234 subjects with long-standing, debilitating CFS/ME at 12 sites. The primary endpoint was the intra-patient change from baseline at Week 40 in exercise tolerance (ET). Secondary endpoints included concomitant drug usage, the Karnofsky Performance Score (KPS), Activities of Daily Living (ADL), and Vitality Score (SF 36). Subjects receiving rintatolimod for 40 weeks improved intra-patient placebo-adjusted ET 21.3% (p = 0.047) from baseline in an intention-to-treat analysis. Correction for subjects with reduced dosing compliance increased placebo-adjusted ET improvement to 28% (p = 0.022). The improvement observed represents approximately twice the minimum considered medically significant by regulatory agencies. The rintatolimod cohort vs. placebo also reduced dependence on drugs commonly used by patients in an attempt to alleviate the symptoms of CFS/ME (p = 0.048). Placebo subjects crossed-over to receive rintatolimod demonstrated an intra-patient improvement in ET performance at 24 weeks of 39% (p = 0.04). Rintatolimod at 400 mg twice weekly was generally well-tolerated. CONCLUSIONS/SIGNIFICANCE: Rintatolimod produced objective improvement in ET and a reduction in CFS/ME related concomitant medication usage as well as other secondary outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT00215800.

Ampligen: a potential toll-like 3 receptor adjuvant for immunotherapy of cancer.

Therapeutic vaccination against cancer-associated antigens represents an attractive option for cancer therapy in view of its potential efficacy, the possibility of long-lasting immunity against the cancer, and safety profile. Cancer patients are however usually immunosuppressed and most cancer-associated antigens are 'self-antigens', making it a significant challenge to vaccinate patients against a cancer-associated antigen. Various immunostimulant adjuvants are therefore under investigation in an effort to boost the immune system to overcome the tolerance to tumour associated self-antigens and the ambient immunosuppressory influence of cytokines and regulatory T-cells (Tregs). Many adjuvants appear to be specific ligands for toll-like receptors (TLR) which are potent activators of innate immune responses [Kwissa M, Kasturi SP, Pulendran B. Expert Rev Vaccines. The Science of Adjuvants 2007 6(October(5)):673-84] [1], activating dendritic cell (DC) maturation and inflammatory cytokine secretion, inducing an increase in the cross talk between the innate and adaptive immune systems, and thereby driving the expansion of CTLs that can destroy cancer cells. However, recently some TLR agonists such as CpG have been shown to generate parallel immunosuppressive and inflammatory responses in innate immune cells capable of induction and expansion of Tregs [Conroy H, Marshall NA, Mills KH. TLR ligand suppression or enhancement of Treg cells? A double-edged sword in immunity to tumours. Oncogene 2008 27(January 7(2)):168-80 [2]; Huang B, Zhao J, Unkeless JC, Feng ZH, Xiong H TLR signaling by tumor and immune cells: a double-edged sword. Oncogene 2008;27(2):218-24] [3]. In this context it is noteworthy that poly(I:C), a synthetic double-stranded RNA polymer and a TLR3 agonist, has been shown in mouse models to be capable of enhancing the T cell response to nonimmunogenic self-antigen linked dendritic cell based vaccine strategy, and stimulating diabetic insulitis in the presence of Tregs [Hornum L, Lundsgaard D, Markholst H. PolyI:C induction of diabetes is controlled by Iddm4 in rats with a full regulatory T cell pool. Ann N Y Acad Sci 2007;1110:65-72] [4]. Ampligen poly(I:C(12)U) is a GMP-grade synthetic analogue of poly(I:C) and therefore suitable for human use. Its effects in a preclinical setting have been recently tested to be similar to poly(I:C) [Hornum L, Lundsgaard D, Markholst H. PolyI:C induction of diabetes is controlled by Iddm4 in rats with a full regulatory T cell pool. Ann N Y Acad Sci 2007;1110:65-72]. In particular, it potently induces in vitro maturation of human monocyte derived DC with sustained bioactive IL12 production. In addition human monocyte derived DC primed with tumour lysate and matured with Ampligen are capable of generating Th1 specific anti-cancer responses in peripheral blood T-cells derived from cancer patients in the presence of ascites medium containing immunosuppressory cytokines. In this review the key findings are summarised and discussed with a view to offering a rationale for the use of Ampligen as a potentially safe adjuvant capable of overcoming the tumour-related immune tolerance mechanisms in a clinical setting.

TLR3 is essential for the induction of protective immunity against Punta Toro Virus infection by the double-stranded RNA (dsRNA), poly(I:C12U), but not Poly(I:C): differential recognition of synthetic dsRNA molecules.

In the wake of RNA virus infections, dsRNA intermediates are often generated. These viral pathogen-associated molecular patterns can be sensed by a growing number of host cell cytosolic proteins and TLR3, which contribute to the induction of antiviral defenses. Recent evidence indicates that melanoma differentiation-associated gene-5 is the prominent host component mediating IFN production after exposure to the dsRNA analog, poly(I:C). We have previously reported that Punta Toro virus (PTV) infection in mice is exquisitely sensitive to treatment with poly(I:C(12)U), a dsRNA analog that has a superior safety profile while maintaining the beneficial activity of the parental poly(I:C) in the induction of innate immune responses. The precise host factor(s) mediating protective immunity following its administration remain to be elucidated. To assess the role of TLR3 in this process, mice lacking the receptor were used to investigate the induction of protective immunity, type I IFNs, and IL-6 following treatment. Unlike wild-type mice, those lacking TLR3 were not protected against PTV infection following poly(I:C(12)U) therapy and failed to produce IFN-alpha, IFN-beta, and IL-6. In contrast, poly(I:C) treatment significantly protected TLR3(-/-) mice from lethal challenge despite some deficiencies in cytokine induction. There was no indication that the lack of protection was due to the fact that TLR3-deficient mice had a reduced capacity to fight infection because they were not found to be more susceptible to PTV. We conclude that TLR3 is essential to the induction of antiviral activity elicited by poly(I:C(12)U), which does not appear to be recognized by the cytosolic sensor of poly(I:C), melanoma differentiation-associated gene-5.

Correlation between breakdown of the blood-brain barrier and disease outcome of viral encephalitis in mice.

Changes in the permeability of the blood-brain barrier (BBB) were evaluated in two mouse models of viral encephalitis. The ability of sodium fluorescein (NaFl) to cross the BBB from the serum into the central nervous system was assayed in animals inoculated with virulent strains of either Banzi or Semliki Forest viruses. To test the hypothesis that increases in BBB permeability were associated with poor disease outcome subsequent experiments measured BBB permeability in conjunction with treatment with the interferon inducer Ampligen (poly I:poly C(12)U). A single intraperitoneal injection of Ampligen (1 mg/kg) administered either 24 h or 4-6 h before, but not 24 h after, virus inoculation with Banzi virus provided significant improvements in survival, viral brain titers, weight change and BBB permeability. In comparison, a similar treatment with Ampligen administered either 24 h or 4-6 h before inoculation with Semliki Forest virus was able to significantly improve weight change, and BBB permeability, but only animals receiving Ampligen 4-6 h pre-virus showed a significantly improved mortality. In general, it was found that evaluation of BBB permeability was a more sensitive indicator of disease outcome and the antiviral efficacy Ampligen than either weight change or brain viral titers.

Effect of exogenous interferon and an interferon inducer on western equine encephalitis virus disease in a hamster model.

Mice are used as models for western equine encephalitis virus (WEEV) infection, but high mortality is generally only seen with intracranial or intranasal challenge, while peripheral inoculation results in approximately 50% mortality and is not dose-dependent. Hamsters were therefore studied as a model for WEEV infection. Hamsters were highly sensitive to intraperitoneal (i.p.) infection with WEEV. Disease progression was rapid, and virus titers in serum, brain, liver, and kidney of infected hamsters peaked between 2 and 4 days post-virus inoculation (dpi). Foci of virus infection were detected in neurons of the cerebral cortex and midbrain. Pre-treatment i.p. with either interferon alfacon-1 (5 microg/kg/day) or with Ampligen (3.2 mg/kg/day) resulted in complete survival, reduced brain titers, and improved weight gain. This model of WEEV infection in hamsters appears to serve as a suitable model for the evaluation of potential therapeutic agents for the treatment of WEE disease.

Mismatched double-stranded RNA: polyI:polyC12U.

Ampligen [polyI:polyC12U] is a mismatched double-stranded RNA that acts by inducing interferon production (immunomodulator) and by activating an intracellular enzyme (RNase-L) against viral RNA transcripts (antiviral). Ampligen, currently under development by Hemispherx Biopharma in the US, acts on the immunological system through T-lymphocyte stimulation and is indicated for the treatment of chronic fatigue syndrome and acquired immunodeficiency deficiency syndrome (AIDS), as part of the combined therapy. Ampligen is available for licensing worldwide. In February 2004, Fujisawa Deutschland GmbH, a subsidiary of Fujisawa Pharmaceutical Co., entered into an option agreement with Hemispherx Biopharma with the intent of becoming a distributor for Ampligen for the potential treatment of chronic fatigue syndrome in Germany, Switzerland and Austria. An option fee of 400,000 euros was paid pursuant to the terms of the option agreement and upon execution of the Distribution Agreement, Fujisawa will pay Hemispherx fees and milestone payments with a potential worth of several millions of dollars. In September 2003, Hemispherx Biopharma Inc. entered into an agreement with Guangdong Medicine Group Corporation to organise clinical trials, marketing, sales and distribution for both of its lead compounds, Ampligen and Alferon N in the People's Republic of China. The agreement stipulates that the Guangdong Medicine Group Corporation (GMC) will conduct clinical trials with Ampligen for the treatment of HIV. All costs related to the trials are to be covered by GMC. Additionally, GMC has to develop and implement marketing and promotional programmes. In May 2003, Hemispherx Biopharma and the Center for Cell and Gene Therapy entered into a research project agreement that will see Ampligen implemented in a protocol used in patients with relapsed EBV-positive Hodgkin's Lymphoma. In March 2002, Esteve and Hemispherx Biopharma entered into a collaborative agreement under which Esteve will be the sole distributor of Ampligen in Spain, Portugal and Andorra for the treatment of chronic fatigue syndrome. Under this agreement, in addition to other terms, Esteve will also collaborate in the drug product development by conducting clinical studies in Spain in patients coinfected with HIV/HCV. In July 2001 Hemispherx Biopharma announced that it had formed a strategic alliance with Empire Health Resources for clinical trials of Ampligen in the treatment of HIV and hepatitis C virus infections. Empire Health Resources, a healthcare management firm, will be responsible for accrual and retention of patients for HIV trials, and protocols for trials in patients with hepatitis C or both HIV and hepatitis C infections. Hemispherx has entered into a collaboration with RED Laboratories, and RED Laboratories NV expects that this will facilitate the continued development of Ampligen. Hemispherx has also entered into an agreement with Schering Plough to use a Schering facility as its principal manufacturing platform in the US. This agreement may be expanded to include other territories. Hemispherx and AOP Orphan Pharmaceuticals have signed a marketing agreement for Ampligen for the treatment of chronic fatigue syndrome for Austria, the Czech Republic, Poland and Hungary. In an arrangement between Hemispherx and Bioclones, Bioclones has certain marketing rights for Ampligen in the Southern Hemisphere, UK and Ireland. In the US, Ampligen has been granted orphan drug status for the treatment of AIDS, renal cell carcinoma (phase II, completed), chronic fatigue syndrome (phase III) and invasive/metastatic malignant melanoma (phase II). In August 2004, Hemispherx announced that it intends to use the proceeds from the private placement of company stock to complete the clinical work for its immunotherapeutics/ antivirals Ampligen and Oragens. Previously, Hemispherx submitted an application to the EMEA for the approval of Ampligen for the treatment of chronic fatigue syndrome; the first stage of th;) for the treatment of chronic fatigue syndrome; the first stage of the regulatory review has been cleared. In 2000, Hemispherx Europe (Hemispherx) obtained orphan drug status for Ampligen for the treatment of chronic fatigue syndrome in the EU, providing Hemispherx with 10 years of marketing exclusivity following the launch of the drug, as well as potential financial research benefits for the agent. In February 2000, Crystaal Corporation (now Biovail Pharmaceuticals Canada) acquired exclusive marketing rights to Ampligen in Canada, where it submitted an NDA for the agent for the treatment of chronic fatigue syndrome. In the meantime, Ampligen has been available since May 1996 under the Canadian Emergency Drug Release Programme for the treatment of chronic fatigue syndrome and immune dysfunction syndrome by Rivex Pharma (Helix BioPharma). Bioclones has initiated clinical studies with Ampligen for the treatment of chronic fatigue syndrome in Australia. The active substance for Ampligen is manufactured by F.H. Faulding Ltd. Clinical treatment programmes for chronic fatigue syndrome in other Pacific Rim countries are planned. Ampligen is available for severe chronic fatigue syndrome on a named patient, cost-recovery basis in South Africa. Hemispherx has developed a 'ready-to-use' liquid formulation of the drug and has begun treating patients with chronic fatigue syndrome in ongoing clinical trials. Hemispherx has also developed an oral version of the drug (Oragen), which is undergoing preclinical evaluation. In February 2001, Hemispherx Biopharma announced that it was initiating phase II/III trials of Ampligen in the treatment of late-stage, multidrug-resistant strains of HIV in the European Union. Patients treated in these studies will have exhausted all other treatment options. In July 2001, Hemispherx stated that Ampligen was being evaluated in a phase IIb trial in patients with HIV in the US. The trial, comprising two studies, REARMI and REARMII (Research/Evaluation of Ampligen for Retroviral Mutations I and II), will evaluate the ability of Ampligen to prevent the emergence of mutated, drug-resistant strains of the virus. 'Several hundred' patients currently on antiretroviral therapy and at risk of viral relapse will be enrolled at centres in Connecticut, New York, Florida and California. A second phase IIb study evaluating the effect of Ampligen on structured treatment interruptions (STI) is also underway. Final results from this study were reported in December 2002. NIH sponsored studies of potential therapies for SARS have identified Ampligen as having unusually high and consistent antiviral activity against human coronavirus, the pathogen implicated as the causative agent of the disease. Ampligen demonstrated very high potency at very low concentrations (0.4 microg/mL) and had a favourable safety profile. In October 2003, Hemispherx announced that, based on these promising new results, the company will stockpile injectible and/or oral formats of Ampligen and Alferon N. Independent researchers have demonstrated the antiviral activity of Ampligen against flaviviruses (West Nile virus, Equine Encephalitis virus, Dengue fever virus and Japanese Encephalitis virus) as well as virus classes associated with bioterrorism. In an animal study, Ampligen was shown to prevent destruction of nerve cells, reduce virus concentrations in the brain and blood stream and increase survival rates. Researchers at the Rega Institute in Belgium have published results from an animal study demonstrating that Ampligen was superior at protecting mice against coxsackie B3 virus-induced myocarditis compared with pegylated interferon. In May 2004 Hemispherx announced that it had filed an expanded US patent application covering the use of Ampligen for the potential treatment and prevention of severe acute respiratory syndrome (SARS) and dreaded emerging viruses.

Effect of interferon-alpha and interferon-inducers on West Nile virus in mouse and hamster animal models.

The recent West Nile virus (WNV) outbreak in the United States has increased the need to identify effective therapies. Studies were conducted in cell culture and in rodent animal models to determine the efficacy of interferon-alpha (IFN-alpha), interferon (IFN) inducers and ribavirin, alone or in combination with IFN, in treating WNV. Intraperitoneal injection of IFN-alpha B/D (qd for 7 days), polyI-polyC(12)U [Ampligen (every other day for 7 days)] and topically applied imiquimod (qd for 7 days), administered from 1 day before viral challenge, were effective in protecting, respectively, 100%, 100% and 70% of BALB/c mice from mortality induced by subcutaneous injection of WNV. When IFN-alpha B/D or Ampligen treatments were delayed to 4-6 h before viral challenge in mice, efficacy was greatly diminished. Infected Syrian golden hamsters treated with interferon alphacon-1 (Infergen) and Ampligen 4-6 h before viral challenge gained more weight and had a greater survival than saline-treated animals. A combination study of subcutaneously administered Infergen (5 to 0.05 microg/kg/day) and ribavirin (75 to 7.5 mg/kg/day) in >7 week old hamsters demonstrated that Infergen was slightly efficacious in reducing mortality and disease signs; however, it was not synergistic in its antiviral effects when combined with ribavirin. Ribavirin treatment alone increased mortality of infected hamsters. The reduced mortality correlated with reduced plasma viraemia. Since WNV-infected patients have already been treated with IFN and ribavirin and future clinical trials have been suggested, this first report of IFN alone or in combination with ribavirin in WNV-infected animal models might provide useful information for subsequent treatment of patients.

The interferon inducer ampligen [poly(I)-poly(C12U)] markedly protects mice against coxsackie B3 virus-induced myocarditis.

Viral replication, as well as an immunopathological component, is assumed to be involved in coxsackie B virus-induced myocarditis. We evaluated the efficacy of the interferon inducer Ampligen on coxsackie B3 virus-induced myocarditis in C3H/HeNHsd mice. The efficacy of Ampligen was compared with that of the interferon inducer poly(inosinic acid)-poly(cytidylic acid) [poly(IC)], alpha interferon 2b (INTRON A), and pegylated alpha interferon 2b (PEG-INTRON-alpha-2b). Ampligen at 20 mg/kg of body weight/day was able to reduce the severity of virus-induced myocarditis, as assessed by morphometric analysis, by 98% (P = 3.0 x 10(-8)). When poly(IC) was administered at 15 mg/kg/day, it reduced the severity of virus-induced myocarditis by 93% (P = 5.6 x 10(-5)). Alpha interferon 2b (1 x 10(5) U/day) and pegylated alpha interferon 2b (5 x 10(5) U/day) were less effective and reduced the severity of virus-induced myocarditis by 66% (P = 0.0009) and 78% (P = 0.0002), respectively. The observed efficacies of Ampligen and poly(IC) were corroborated by the observation that the drugs also markedly reduced the virus titers in the heart, as detected by (i) quantitative real-time reverse transcription-PCR and (ii) titration for infectious virus content. Whereas the electrocardiograms for untreated mice with myocarditis were severely disturbed, the electrocardiographic parameters were normalized in Ampligen- and poly(IC)-treated mice. Even when start of treatment with Ampligen was delayed until day 2 postinfection, a time at which lesions had already appeared in untreated control animals, a marked protective effect on the development of viral myocarditis (as assessed at day 6 postinfection) was still noted.

Interferons, interferon inducers, and interferon-ribavirin in treatment of flavivirus-induced encephalitis in mice.

We evaluated the prophylactic and therapeutic efficacy of interferon alpha-2b, pegylated interferon alpha-2b, poly(I. C), and Ampligen against Modoc virus encephalitis in an animal model for flavivirus infections. All compounds significantly delayed virus-induced morbidity (paralysis) and mortality (due to progressive encephalitis). Viral load (as measured on day 7 postinfection) was significantly reduced by 80 to 100% in the serum, brain, and spleen in mice that had been treated with either interferon alpha-2b, pegylated interferon alpha-2b, poly(I. C), or Ampligen. We also studied whether a combination of interferon alpha-2b and ribavirin (presently the standard therapy for the treatment of infections with hepatitis C virus) would be more effective than treatment with interferon alone. However, ribavirin did not enhance the inhibitory effect of interferon therapy in this animal model for flavivirus infections.

Fatigue that doesn't go away.

The classic profile of the chronic fatigue syndrome (CFS) patient is a white, middle-age female. Characterized by profound fatigue, CFS often starts with an acute viral infection. While today's medicine provides symptomatic relief, research is offering innovative insights. With this research, is a cure for these patients just around the corner?

Antiviral activity of biological response modifiers in a murine model of AIDS. Requirement for augmentation of natural killer cell activity and synergy with oral AZT.

We employed the Rauscher murine leukemia virus (RMuLV) as a murine retrovirus model of AIDS, to test biological response modifiers (BRM) and antiviral agents for potential therapeutic activity against the human immunodeficiency virus (HIV). We examined the relationship between the augmentation of natural killer (NK) cell activity and antiviral efficacy of a series of BRM, most of which are known inducers of interferon, in this model. Poly [I,C]-LC, MVE-2, and CL 246,738, but not Ampligen, soluble glucan, or 7-thia-8-oxoguanosine, consistently produced antiviral activity. In addition, the combination of suboptimal doses of oral 3'-azido-3'-deoxythymidine (AZT) (in drinking water) and poly [I,C]-LC produced a synergistic antiviral effect. With all the BRM tested, a consistent pattern emerged, namely that antiviral activity always correlated with the augmentation of splenic NK cell activity in infected animals. For instance, poly [I,C]-LC boosted NK activity much more in infected mice treated therapeutically (treatment initiated after infection) than prophylactically (treatment initiated before infection), and it had greater antiviral activity therapeutically than prophylactically. For the BRM tested, antiviral activity did not occur without augmentation of NK activity in infected mice. In contrast, augmentation of NK activity in uninfected mice bore no relationship to antiviral activity. Furthermore, elimination of NK cells by treating mice with anti-asialo GM1 abolished the antiviral activity of poly [I,C]-LC. Although splenic NK activity was ablated by anti-asialo GM1, serum interferon levels were not affected by this treatment. These results point to a causal connection between the augmentation of NK cell activity and the antiviral efficacy of these BRM in this murine AIDS model. NK cells thus appear to play a key role in resistance to this retrovirus, as has been suggested for HIV.

Results of a double-blind placebo-controlled study of the double-stranded RNA drug polyI:polyC12U in the treatment of HIV infection.

In this multicenter, randomized, double-blind study the activity of polyI:polyC12U administered with zidovudine was evaluated in the treatment of HIV infection. Thirty-six HIV-positive, pre-AIDS individuals (100-500 CD4+ cells/mm3) who had had at least six months of zidovudine therapy received polyI:polyC12U (400 or 700 mg) or placebo twice weekly with zidovudine. PolyI:polyC12U subjects with baseline CD4+ counts > or = 300/mm3 showed a trend towards reduced CD4+ loss versus placebo recipients. PolyI:polyC12U subjects were more likely to exhibit positive delayed-type hypersensitivity responses than placebo recipients. Placebo subjects crossing over to polyI:polyC12U therapy demonstrated improved CD4+ and delayed-type hypersensitivity responses. PolyI:polyC12U subjects with baseline CD4+ counts > or = 300/mm3 were less likely to develop AIDS than similar placebo subjects. PolyI:polyC12U therapy of HIV-positive subjects restored or stabilized immune function as indexed by delayed-type hypersensitivity reactivity and, in individuals with CD4+ counts > 300/mm3, abrogated CD4+ loss and reduced disease progression. PolyI:polyC12U was generally well-tolerated in this zidovudine-treated population. No subject discontinued therapy due to an adverse reaction or aberrant laboratory parameter.

New "ThetaSwitch" drug may increase long-term survival in HIV disease.

AIDS: Hemisphere Biopharma reports that its nucleic acid compound, Ampligen, in conjunction with ZDV, switched a significant percentage of HIV-infected clinical trial subjects from an unresponsive Theta status to a responsive one. Driving the immune reaction in the apparently correct direction by selectively controlling the Theta Switch was demonstrated in vivo by the ability of certain nucleic acids to throw the Switch correctly and to elicit the production of a specific biological cocktail of cytokines, including interferon, interleukin-2, and interleukin-12. These mediators or biochemical workhorses of the Theta 1 Switch apply to the cell-mediated immune response, or positive skin test response.^ieng