SBIR-STTR Award

There is an urgent need to discover more effective therapeutic regimens for fungal infections. Nosocomial infections caused by Candida albicans have a 50% mortality rate. Aspergillosis is a leading cause of death in organ transplant recipients, as well as patients suffering from cancer and auto-immune disorders. The annual cost of treating fungal infections is about $2.6 billion in the United States and is increasing due to the larger number of immunocompromised patients who suffer from these illnesses. The emergence of fungal drug resistance to widely used antifungals including triazoles and echinocandins further compromises the efficacy of the limited armamentarium of antifungal therapeutics. A number of in vitro and in vivo studies have established that molecules which inhibit the fungal protein, calcineurin, are highly synergistic with several important classes of antifungal therapeutics including triazoles and echinocandins. However, a great challenge with exploiting fungal calcineurin as a therapeutic target is the structural similarity to human calcineurin, and that inhibition of human calcineurin causes severe immunosuppression and toxicity. By exploiting recently developed chemistry to generate a variety of FK506 analogues, we have isolated a molecule which has equivalent or higher antifungal activity than FK506 and negligible immunosuppression. When combined with common antifungals, this molecule had excellent potency against drug resistant clinical isolates. Encouraged by these initial results, we wish to create a larger library of FK506 analogues in order to discover molecules that are non-toxic, highly antifungal, and synergistic with existing therapeutics. Our overall goal is to develop an effective combination therapy which can be applied to drug resistant fungal infections. Our aims are: Aim 1. Design and synthesis of a 1000 member focused library of FK506 analogues. Aim 2. Screen and select library for lack of immunosuppression. Aim 3. Screen and select library for antifungal effects when combined with established antifungal drugs.

Public Health Relevance:
Fungal infections represent a significant challenge due to the limited armamentarium available to treat diseases caused by fungi. Nosocomial infections caused by Candida albicans have a 50% mortality rate. Amplyx proposes a new combination therapy approach to treating drug resistant fungal infections via the design and synthesis of non-immunosuppressive molecules to inhibit fungal calcineurin that can be co-administered with existing antifungals.

Thesaurus Terms:
2-Propen-1-Amine;3-Aminopropylene;Adverse Effects;Allylamine;Antifungal Agents;Antifungal Drug;Antifungal Drug Resistance;Antifungal Drug Resistant;Antifungal Resistant;Aspergillosis;Aspergillus;Assay;Bioassay;Biologic Assays;Biological Assay;C. Albicans;C.Albicans;Calcineurin;Calcineurin Antagonist;Calcineurin Inhibitor;Cancers;Candida;Candida Albicans;Caspofungin;Cause Of Death;Cells;Chemistry;Clinical;Clinical, Transplantation, Organ;Co-Stimulator;Combined Modality Therapy;Costimulator;Disease;Disorder;Drug Resistance;Epidermal Thymocyte Activating Factor;Fk 506;Fk506;Fk506-Binding Protein 1;Fk506-Binding Protein 1a;Fkbp-12;Fkbp12;Fluconazole;Fungal Drug Resistance;Fungal Gene Products;Fungal Gene Proteins;Fungal Proteins;Fungus Diseases;Fungus Drug Resistant;Goals;Grafting Procedure;H+ Element;Hospital Infections;Hospital Acquired Infection;Human;Hydrogen Ions;Ic50;Il-2;Il2 Protein;Immune Diseases;Immune Disorders;Immune Dysfunction;Immune System Diseases;Immune System Disorder;Immunocompromised;Immunocompromised Host;Immunocompromised Patient;Immunologic Diseases;Immunological Diseases;Immunosuppressants;Immunosuppressed Host;Immunosuppression Effect;Immunosuppressions (Physiology);Immunosuppressive Agents;Immunosuppressive Effect;In Vitro;Infection;Inhibitory Concentration 50;Interleukin 2;Interleukin 2 Precursor;Interleukin Ii;Interleukin-2;Interleukine 2;Interleukine 2 Precursor;Interleukine Ii;Lc/Ms;Libraries;Lymphocyte Mitogenic Factor;Macrophilin-12;Malignant Neoplasms;Malignant Tumor;Man (Taxonomy);Marketing;Membrane;Methods;Mitogenic Factor;Modern Man;Monilia;Mortality;Mortality Vital Statistics;Multimodal Therapy;Multimodal Treatment;Multimodality Treatment;Mycoses;Natural Immunosuppression;Nosocomial Infections;Organ Transplantation;Organ Transplants;Organ Transplants, Including Bone Marrow For Dct;Pp2b;Patients;Protein Phosphatase-2b;Protons;Regimen;Resistance;Sales;Screening Procedure;T Cell Growth Factor;T-Cell Growth Factor;T-Cell Stimulating Factor;Tacrolimus Binding Protein 1a;Therapeutic;Therapeutic Fungicides;Thymocyte Stimulating Factor;Toxic Effect;Toxicities;Transplant Recipients;Transplantation Surgery;Treatment Side Effects;Triazoles;United States;Voriconazole;Analog;Anti-Fungal;Anti-Fungal Drug Resistance;Anti-Fungal Drug Resistant;Anti-Fungal Resistance;Anti-Fungal Resistant;Antifungal Resistance;Antifungals;Base;Biological Adaptation To Stress;Combination Therapy;Combined Modality Treatment;Combined Treatment;Cost;Design;Designing;Diflucan;Disease/Disorder;Drug Resistant;Fungal Infection;Fungus;Fungus Drug Resistance;Fungus Infection;Fungus Protein;Immune Suppression;Immunosuppressed Patient;Immunosuppression;Immunosuppressive;In Vivo;Institutional Infection;Liquid Chromatography Mass Spectrometry;Malignancy;Member;Membrane Structure;Multimodality Therapy;Mutant;Neoplasm/Cancer;Organ Allograft;Organ Graft;Organ Xenograft;Posaconazole;Reaction;Crisis;Resistance To Drug;Resistance To Anti-Fungal;Resistance To Antifungal;Resistant;Resistant To Drug;Resistant To Anti-Fungal;Resistant To Antifungal;Screening;Screenings;Side Effect;Stress Response;Stress;Reaction;Success;Theories;Therapeutic Target;Therapy Adverse Effect;Transplant Patient;Treatment Adverse Effect

Despite the introduction of newer triazoles and echinocandins, invasive fungal infections (IFI's) including invasive candidiasis (IC) remain very difficult to treat with currently available antifungals. The annual cost burden of treating nosocomial fungal infections exceeds $2.6 billion a year in the United States alone. Worldwide, the annual incidence of IC is about 300,000. Children suffering from the most common pediatric cancer, acute leukocytic leukemia have an approximate 5% mortality rate; however, if the patient develops invasive candidiasis, their mortality rate increases 4 to 8 times to 20-40%. Currently, only three classes of antifungal drugs are employed to treat IC, and no new class has been introduced to the market for thirteen years. It has been widely recognized that antifungal treatments which address mechanisms of drug resistance and could be combined with existing therapeutics would provide a tremendous advantage over currently available treatments. Unfortunately, unlike cancer chemotherapy, there are relatively few treatment regimens that productively combine different antifungals to achieve better therapeutic outcomes and address drug resistance without the added burden of drug toxicity. Work performed in the lab of our colleague, Prof. Joe Heitman and others has revealed the tremendous therapeutic potential of inhibiting the fungal protein, calcineurin. Calcineurin inhibition compromises the cell wall stressresponse of Candida albicans, NCAC's, Aspergillus fumigatus, Cryptococcus neoformans, and other pathogenic fungi. Furthermore, when combined with triazoles, echinocandins, or allylamines, calcineurin inhibitors are highly synergistic and can reduce the MIC value by a factor of 50 or more. It has also been observed that resistant clinical isolates of C. albicans, A.fumigatus, and other fungi become susceptible to antifungal therapeutics when combined with a calcineurin inhibitor both in vitro and in vivo. However, the lack of a potent, antifungal calcineuin inhibitor that does not cause immunosuppression has hindered progress in exploiting this novel target. Moreover, calcineurin inhibitors are typically are large, structurally complex (>700 Daltons) molecules and this has hindered the facile creation of analogues for testing. Employing newly developed chemistry and structural insight, we propose developing a potent, non-immunosuppressive fungal calcineurin inhibitor, building on progress from our Phase I project. Aim 1. Generate closely related analogs of hits resulting from screens from Phase I. Aim 2. Characterize compounds in vitro for advancement. Iterate library as required. Aim 3. Characterize compounds in vivo for pharmacokinetics and efficacy.

Thesaurus Terms:
Acute;Address;Allylamine;Analog;Animal Model;Antibiotic Resistance;Antibiotics;Antifungal Agents;Aspergillus Fumigatus;Biological Adaptation To Stress;Calcineurin;Calcineurin Inhibitor;Calcium;Calmodulin;Cancer Patient;Candida;Candida Albicans;Candidiasis;Caring;Caspofungin;Cell Survival;Cell Wall;Centers For Disease Control And Prevention (U.S.);Chemicals;Chemistry;Chemotherapy-Oncologic Procedure;Child;Clinical;Combined Modality Therapy;Complex;Cost;Cryptococcus Neoformans;Cytotoxic Chemotherapy;Cytotoxicity;Dalton;Design;Disease;Drug Kinetics;Drug Resistance;Drug Toxicity;Effective Therapy;Fk506;Fluconazole;Fungal Proteins;Fungus;Generations;Goals;Health;Hiv Seropositivity;Human;Immunocompromised Host;Immunosuppressive Agents;Improved;In Vitro;In Vivo;Incidence;Individual;Infection;Inhibitor/Antagonist;Insight;Knowledge;Lead;Leukemia;Libraries;Life;Liquid Chromatography Mass Spectrometry;Malignant Childhood Neoplasm;Mammalian Cell;Marketing;Medical Device;Membrane;Methods;Mortality Vital Statistics;Mycoses;Names;Natural Immunosuppression;Nosocomial Infections;Novel;Outcome;Pathogen;Patients;Phase;Phase 1 Study;Phosphoric Monoester Hydrolases;Premature Infant;Prevalence;Process;Protons;Public Health Relevance;Publishing;Relative (Related Person);Reporting;Resistance;Roentgen Rays;Sales;Screening;Screening Result;Structural Chemistry;Structure;Structure-Activity Relationship;Systemic Infection;Tacrolimus Binding Protein 1a;Tacrolimus Binding Proteins;Testing;Theories;Therapeutic;Therapeutic Index;Therapeutic Target;Three Dimensional Structure;Time;Toxic Effect;Transplant Recipients;Treatment Outcome;Treatment Protocols;Triazoles;United States;Virulence;Work;