Tag: NOVEL

  • Thymalin

    Plain-language summaryIntrigue 58 / 100

    Thymalin is a Russian-developed bovine thymus peptide preparation used as an immunomodulator for elderly patients and immune disorders. Combined with epitalon in Khavinson’s longevity research. Not stocked by Kodiac. This monograph is provided for research and educational reference.

    Intrigue 0–100 blends mechanism novelty, evidence strength, and translational potential. Kodiac editorial, not peer-reviewed.

    Thymic polypeptide bioregulator complex with immunomodulatory and geroprotective activity

    A heterogeneous polypeptide complex isolated from calf thymus, developed at the Military Medical Academy in Leningrad as a thymic bioregulator for immune restoration, distinguished from other thymic peptide preparations by its multicomponent composition containing the immunomodulatory dipeptides L-glutamyl-L-tryptophan and L-lysyl-L-glutamic acid and the tripeptide L-glutamyl-L-aspartyl-L-proline.

    Abstract

    Thymalin is a standardized polypeptide complex isolated from the thymus gland of calves by acid hydrolysis and ultrafiltration, containing peptide fractions in the 1,000 to 10,000 dalton molecular weight range. Developed at the Military Medical Academy in Leningrad (now Saint Petersburg) by Vladimir Khavinson and Vyacheslav Morozov in the 1970s, the preparation was registered as an immunomodulatory pharmaceutical in the Soviet Union in 1982 and has remained in clinical use in the Russian Federation for more than four decades. Unlike the structurally defined thymic peptides thymosin alpha-1 (a 28-amino-acid single-sequence peptide), thymulin (a zinc-dependent nonapeptide), and thymopentin (a synthetic pentapeptide fragment of thymopoietin), Thymalin is a multicomponent extract whose principal bioactive constituents have been identified by reversed-phase high-performance liquid chromatography as the dipeptide L-glutamyl-L-tryptophan (Glu-Trp, subsequently developed independently as Thymogen), the dipeptide L-lysyl-L-glutamic acid (Lys-Glu, developed as Vilon), and the tripeptide L-glutamyl-L-aspartyl-L-proline (Glu-Asp-Pro, developed as Crystagen). The molecular mechanism of the immunoprotective activity is attributed to the capacity of these short peptides to bind selectively to double-stranded DNA sequences and to histone proteins, thereby modulating chromatin conformation, gene expression, and the synthesis of immune system proteins including interleukins, interferons, heat-shock proteins, and components of the fibrinolytic system. In experimental systems, Thymalin stimulates the differentiation and functional activity of T-lymphocyte subpopulations (CD4+ and CD8+), normalizes the ratio of T-helper to T-suppressor cells, enhances natural killer cell activity and phagocytosis, and modulates the balance between pro-inflammatory and anti-inflammatory cytokines. The geroprotective properties of Thymalin are supported by a prospective clinical observation of 266 elderly subjects over 6 to 8 years conducted at the St. Petersburg Institute of Bioregulation and Gerontology and the Institute of Gerontology of the Ukrainian Academy of Medical Sciences, in which Thymalin-treated subjects exhibited 2.0- to 2.1-fold lower mortality compared to controls receiving standard geriatric care, with further reductions (4.1-fold lower mortality) observed in a subgroup receiving annual combined Thymalin and Epithalamin treatment for 6 years. More recently, a prospective randomized single-blind controlled trial of Thymalin (10 mg intramuscular daily for 10 days) in 80 elderly patients with severe COVID-19 reported a 92 percent increase in blood lymphocytes, 6.5-fold reduction in interleukin-6, halved in-hospital mortality (19.4 percent versus 40.9 percent in controls), and more rapid clinical improvement (80.5 percent versus 59 percent). In vitro studies have demonstrated that Thymalin reduces expression of the stem cell markers CD44 and CD117 by 2- to 3-fold while increasing expression of CD28 (a marker of mature T lymphocytes) by 6.8-fold, consistent with stimulation of hematopoietic stem cell differentiation into functional T cells. The compound is administered by intramuscular or subcutaneous injection in short cyclical courses of 5 to 10 days at doses of 5 to 10 mg daily, with clinical effect reported to persist for weeks to months following each treatment course. The safety record across more than 40 years of clinical use indicates minimal adverse events, principally limited to injection-site reactions. This monograph reviews the composition, extraction, and characterization of Thymalin; the molecular pharmacology of its constituent peptides at the level of DNA binding, histone interaction, and gene expression regulation; the pharmacokinetic properties; the preclinical evidence base across immune restoration, geroprotection, and oncology models; the clinical evidence in elderly immune decline, respiratory infections, perioperative immune suppression, and COVID-19; sourcing and quality verification considerations; reconstitution and handling protocols; stack interactions with other immunomodulatory agents; the adverse-event and safety profile; and a comparative assessment of five alternative thymic and immunomodulatory peptide preparations against Thymalin on five competency standards (novelty, effect size, promising potential, side-effect profile, and overall validation).

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  • Alpha-Klotho

    Type I transmembrane protein and circulating endocrine factor of the glycosyl hydrolase family 1 superfamily with obligate FGF23 co-receptor and pleiotropic anti-aging functions

    A kidney-derived transmembrane glycoprotein and its shed soluble ectodomain, identified through insertional mutagenesis in 1997 as a suppressor of aging phenotypes in mice, functioning both as an obligate co-receptor for fibroblast growth factor 23 in mineral metabolism and as a circulating endocrine factor that inhibits insulin/IGF-1, Wnt, TGF-beta, and NF-kappaB signaling pathways with demonstrated neuroprotective, cardioprotective, and renoprotective activity in preclinical models.

    Abstract

    Alpha-Klotho (alpha-KL) is a 130 kDa type I single-pass transmembrane protein encoded by the KL gene on human chromosome 13q13.1, first identified in 1997 by Kuro-o et al. through characterization of an insertional mutation in mice that produced a syndrome of accelerated aging encompassing soft tissue calcification, arteriosclerosis, skin atrophy, osteoporosis, emphysema, gonadal dysplasia, and dramatically shortened lifespan [1]. The protein comprises a short intracellular domain, a single transmembrane helix, and a large extracellular region containing two tandem glycosyl hydrolase family 1 (GH1) domains, designated KL1 and KL2, which share sequence homology with family 1 beta-glucosidases but lack catalytic activity against conventional substrates due to substitutions in the active-site residues. The extracellular domain undergoes proteolytic shedding by ADAM10, ADAM17, and BACE1, generating a soluble ectodomain (sKL) comprising KL1 and KL2 that circulates as an endocrine factor detectable in plasma, cerebrospinal fluid, and urine. A shorter secreted isoform containing only KL1 is produced by alternative mRNA splicing.

    In its membrane-bound form, alpha-Klotho functions as an obligate co-receptor for fibroblast growth factor 23 (FGF23), forming a ternary complex with FGF receptor 1c (FGFR1c) that is essential for phosphaturic signaling in the renal proximal tubule and for suppression of 1,25-dihydroxyvitamin D3 (calcitriol) synthesis. The crystal structure of the alpha-Klotho/FGFR1c/FGF23 ternary complex, resolved by Chen et al. (2018) at 3.0 angstrom resolution, demonstrated that the KL2 domain of alpha-Klotho cradles FGF23 with a receptor-binding arm extending from the KL1-KL2 interdomain cleft, creating a composite binding surface for FGF23 engagement [2]. Loss of this co-receptor function produces the hyperphosphatemia, hypervitaminosis D, and ectopic calcification that characterize the kl/kl mouse phenotype and that are recapitulated in FGF23 knockout mice.

    Independent of the FGF23 co-receptor function, soluble alpha-Klotho acts as a circulating endocrine factor with pleiotropic anti-aging activity. Characterized signaling activities include inhibition of the insulin/insulin-like growth factor 1 (IGF-1) pathway through suppression of receptor autophosphorylation; suppression of Wnt/beta-catenin signaling through direct binding to Wnt ligands; inhibition of transforming growth factor beta (TGF-beta) type II receptor signaling and downstream Smad phosphorylation; suppression of NF-kappaB-driven inflammatory transcription; and regulation of ion channel and transporter activity in the renal tubule, including TRPV5, TRPV6, ROMK1, and the Na+/K+-ATPase [3, 4, 5]. These FGF23-independent activities are the molecular basis for the broader anti-aging, neuroprotective, cardioprotective, and anti-fibrotic effects observed in gain-of-function and supplementation studies.

    Circulating soluble alpha-Klotho levels decline with age in humans, beginning approximately in the fourth decade of life, and are markedly reduced in chronic kidney disease, where loss of renal alpha-Klotho expression precedes and contributes to the mineral and bone disorder, cardiovascular calcification, and accelerated aging phenotype of uremia [6]. Epidemiological studies have identified inverse associations between circulating soluble alpha-Klotho concentrations and all-cause mortality, cardiovascular events, and cognitive decline in community-dwelling older adults [7]. The KL-VS haplotype (defined by the F352V and C370S variants, rs9536314 and rs9527025) has been associated in some cohorts with altered klotho secretion, cortical brain volume, and cognitive resilience in aging, though replication across large cohorts remains inconsistent [8, 9].

    Preclinical studies have demonstrated that recombinant alpha-Klotho protein administration, adeno-associated virus-mediated KL gene transfer, and transgenic KL overexpression produce renoprotection in ischemia-reperfusion injury and unilateral ureteral obstruction models; cardioprotection with attenuation of left ventricular hypertrophy and fibrosis; suppression of vascular calcification; and cognitive enhancement in aged, young, and alpha-synuclein transgenic mice through NMDA receptor-dependent glutamatergic mechanisms [10, 11, 12, 13]. A 2023 study in aged nonhuman primates demonstrated that a single subcutaneous injection of a klotho protein fragment enhanced spatial and working memory, representing the first primate cognitive enhancement data for the compound [14].

    As of 2026, alpha-Klotho is in early clinical development. Klothea Bio launched a Phase 1b randomized, double-blind, placebo-controlled trial of AKL003, an alpha-Klotho mRNA therapeutic administered intravenously, in healthy adult volunteers in February 2026. Klotho Neurosciences is advancing KLTO-202, a KL gene therapy, toward first-in-human studies for amyotrophic lateral sclerosis. No alpha-Klotho protein or gene therapy product has received regulatory approval in any jurisdiction. Recombinant human alpha-Klotho protein is available from multiple research suppliers (R&D Systems, Abcam, Sino Biological, Thermo Fisher) for in vitro and preclinical applications. This monograph reviews the molecular identification, structural biology, receptor pharmacology, preclinical pharmacology across organ systems, the emerging clinical evidence base, sourcing and handling considerations, stack interactions, safety signal, and a comparative assessment of five anti-aging intervention candidates against alpha-Klotho on five competency standards.

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  • Apelin-13

    Endogenous bioactive peptide agonist of the apelin receptor (APJ/APLNR), a class A G protein-coupled receptor

    A pyroglutamyl-modified tridecapeptide derived from the C-terminus of preproapelin, identified as the predominant circulating isoform and the highest-potency endogenous agonist of the APJ receptor, with characterized cardiovascular inotropic, vasodilatory, aquaretic, metabolic, and neuroprotective activities.

    Abstract

    Apelin-13, the C-terminal tridecapeptide fragment of the 77-amino-acid preproapelin precursor, is the most potent endogenous agonist of the apelin receptor (APJ, also designated APLNR), a class A rhodopsin-like G protein-coupled receptor originally cloned as an orphan receptor in 1993 by O’Dowd et al. on the basis of sequence homology with the angiotensin II type 1 receptor. The receptor was deorphanized in 1998 by Tatemoto and colleagues at the Takeda Chemical Research Institute, who isolated apelin from bovine stomach extracts using an extracellular acidification assay on APJ-expressing Chinese hamster ovary cells and demonstrated that apelin-13 displayed 8- to 60-fold higher potency than the longer apelin-36 isoform. The predominant circulating form in human plasma is [Pyr1]apelin-13 (pyroglutamyl apelin-13), in which the N-terminal glutamine residue undergoes spontaneous or enzymatic cyclization to pyroglutamate, conferring modest resistance to aminopeptidase degradation and representing the principal bioactive isoform in cardiovascular tissue and plasma.

    Apelin-13 activates APJ with sub-nanomolar potency (EC50 approximately 0.37 nM in cellular acidification assays), coupling predominantly through Gi/o proteins to inhibit adenylyl cyclase and reduce intracellular cAMP, through Gq/11 to activate phospholipase C and mobilize intracellular calcium, and through G12/13 to engage RhoA-dependent cytoskeletal rearrangement. The receptor also recruits beta-arrestin 1 and 2, mediating receptor internalization and activating extracellular signal-regulated kinase 1/2 (ERK1/2) through G protein-independent pathways. The downstream signaling cascade includes activation of phosphoinositide 3-kinase (PI3K)/Akt, endothelial nitric oxide synthase (eNOS), AMP-activated protein kinase (AMPK), and inhibition of reactive oxygen species generation, collectively producing the cardiovascular, metabolic, and cytoprotective effects that define the pharmacological profile.

    The cardiovascular pharmacology of apelin-13 is the most extensively characterized domain. In human clinical studies, systemic infusion of [Pyr1]apelin-13 at 30 to 300 nmol/min produces a sustained approximately 10 percent increase in cardiac index, increased ejection fraction, reduced systemic vascular resistance by approximately 12 percent, and reduced mean arterial pressure by approximately 4 percent, effects observed in both healthy volunteers and patients with chronic heart failure and chronic kidney disease. The mechanism involves direct positive inotropic action on cardiomyocytes through APJ-mediated calcium sensitization, nitric oxide-dependent vasodilation in resistance arteries, and counter-regulatory opposition to the renin-angiotensin-aldosterone system. Preclinical models demonstrate cardioprotective effects in myocardial infarction, ischemia-reperfusion injury, pressure-overload hypertrophy, and diabetic cardiomyopathy, with mechanisms including salvage of the peri-infarct border zone, mobilization of endogenous cardiac stem cells, and suppression of pathological fibrosis.

    The renal pharmacology is defined by the functional antagonism between apelin and arginine vasopressin (AVP) at the collecting duct. Apelin-13 inhibits vasopressin-induced translocation of aquaporin 2 (AQP2) water channels to the apical membrane of principal cells through Gi-mediated inhibition of cAMP/protein kinase A signaling, producing a diuretic (aquaretic) effect that opposes AVP-driven water reabsorption. This reciprocal regulation positions the apelin/AVP axis as a physiological rheostat for water homeostasis, with therapeutic implications for hyponatremia and states of AVP excess.

    Metabolic pharmacology encompasses insulin-sensitizing and glucoregulatory effects. Apelin-13 administration in diabetic rodent models reduces blood glucose, increases serum insulin, improves pancreatic islet mass, and enhances glucose uptake in skeletal muscle through AMPK-dependent GLUT4 translocation. Neuroprotective activity has been demonstrated in models of ischemic stroke, diabetes-associated cognitive decline, and excitotoxic injury, with mechanisms including antioxidant defense through the SIRT3/FoxO3 pathway, anti-inflammatory cytokine modulation, and direct neuronal survival signaling through PI3K/Akt.

    The principal pharmacokinetic limitation of apelin-13 is its extremely short plasma half-life. Native [Pyr1]apelin-13 has a plasma half-life of approximately 21 to 24 minutes in rodents, driven by rapid proteolytic degradation at the Leu5-Ser6 peptide bond by neprilysin, angiotensin-converting enzyme 2 (ACE2), and plasma kallikrein. This has motivated extensive medicinal chemistry efforts to develop stabilized analogues (macrocyclic peptides, D-amino acid substitutions, PEGylation) and small-molecule APJ agonists (AMG-986, BMS-986224, azelaprag) for chronic administration.

    This monograph reviews the chemistry, identification, and structural biology of apelin-13; the discovery and deorphanization history of the APJ receptor; the molecular pharmacology across Gi, Gq, G12/13, and beta-arrestin pathways; the pharmacokinetic profile and proteolytic degradation pathways; the preclinical evidence base across cardiovascular, renal, metabolic, and neurological domains; the clinical evidence from human hemodynamic studies; sourcing and quality verification for research-grade material; reconstitution and handling protocols; stack interactions with vasoactive and metabolic agents; the adverse-event and safety profile; and a comparative assessment of five APJ receptor agonist candidates against apelin-13 on five competency standards. The compound is not an approved therapeutic agent in any jurisdiction. It is supplied as a research-grade peptide; investigators should obtain analytical confirmation of identity, purity, and peptide content on every lot.

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    FOR RESEARCH USE ONLY. Not for medical, diagnostic, or therapeutic purposes. Not for human consumption. All information is provided for research and educational purposes only.

  • Beta-Lapachone

    NQO1-bioactivatable ortho-naphthoquinone with selective tumor cytotoxicity through futile redox cycling and PARP1 hyperactivation

    A naturally derived 1,2-naphthoquinone from the lapacho tree, bioactivated selectively by NAD(P)H:quinone oxidoreductase 1 to induce tumor-specific programmed necrosis through futile redox cycling, massive reactive oxygen species generation, DNA damage, PARP1 hyperactivation, and catastrophic NAD+/ATP depletion.

    Abstract

    Beta-lapachone is a naturally occurring ortho-naphthoquinone originally isolated from the heartwood of Tabebuia avellanedae (pau d’arco, lapacho) and synthesized from the prenylated naphthoquinone lapachol by acid-catalyzed cyclization. The compound is the canonical substrate of NAD(P)H:quinone oxidoreductase 1 (NQO1, DT-diaphorase, EC 1.6.5.2), a two-electron reductase that is overexpressed 5- to 100-fold in the majority of solid human cancers, including non-small cell lung, pancreatic ductal adenocarcinoma, breast, prostate, and head and neck squamous cell carcinomas, relative to matched normal tissue. NQO1-mediated two-electron reduction of beta-lapachone produces an unstable hydroquinone that spontaneously autoxidizes back to the parent quinone in a futile redox cycle consuming approximately 60 moles of NAD(P)H per mole of drug over a 2-hour exposure window. This cycle generates massive superoxide and hydrogen peroxide fluxes within the tumor cell, producing extensive oxidative DNA damage (predominantly single-strand breaks and oxidized bases) that triggers hyperactivation of poly(ADP-ribose) polymerase 1 (PARP1) in the presence of elevated nuclear calcium. PARP1 hyperactivation consumes the cellular NAD+ pool into branched poly(ADP-ribose) polymers, producing catastrophic NAD+ and ATP depletion, mu-calpain activation, apoptosis-inducing factor (AIF) translocation from mitochondria to the nucleus, and programmed necrosis that is mechanistically distinct from classical apoptosis and independent of caspase activation, p53 status, and Bcl-2 family protein expression. The NQO1 dependence of the cytotoxic mechanism confers tumor selectivity: NQO1-negative cells (including most normal tissues) are resistant to beta-lapachone at pharmacologically achievable concentrations, and dicoumarol (an NQO1 inhibitor) completely abrogates cytotoxicity in NQO1-positive cancer cell lines. Beta-lapachone was advanced into clinical development as ARQ 501 (an intravenous hydroxypropyl-beta-cyclodextrin inclusion complex) by ArQule, Inc. and subsequently as ARQ 761 (an improved intravenous formulation) by the University of Texas Southwestern Medical Center. Phase I trials in patients with advanced solid tumors established a maximum tolerated dose of 390 mg/m2 as a 2-hour intravenous infusion every other week, with dose-limiting toxicities of hemolytic anemia and methemoglobinemia attributable to off-target redox cycling interaction with cytochrome b5 reductase in erythrocytes. A Phase II trial of ARQ 501 in combination with gemcitabine in treatment-naive unresectable pancreatic adenocarcinoma demonstrated disease stabilization but did not produce objective tumor responses sufficient for registration. A separate clinical derivative, MB12066, was developed for metabolic syndrome indications and completed first-in-human pharmacokinetic and tolerability studies at oral doses of 10 to 400 mg. Beyond anticancer applications, beta-lapachone exhibits anti-inflammatory activity through suppression of NF-kappaB-driven cytokine expression in activated macrophages and microglia, anti-obesity effects through stimulation of energy expenditure and white adipose tissue browning via NQO1-dependent NADH oxidation, and antimicrobial activity against Trypanosoma cruzi and Mycobacterium tuberculosis. This monograph reviews the chemistry, synthesis, and natural product origin of beta-lapachone; the NQO1-dependent futile redox cycling mechanism in molecular detail; the comprehensive pharmacokinetic record including formulation challenges; the preclinical and clinical evidence base across oncology, metabolic, and inflammatory indications; the reconstitution, sourcing, and handling considerations for laboratory work; and a comparative assessment of five NQO1-targeted or naphthoquinone-class compounds against beta-lapachone on five competency standards (novelty, effect size, promising potential, side-effect profile, and overall validation). The compound is not approved by any regulatory authority for any therapeutic indication. It is available as a research-grade preparation; investigators should obtain analytical confirmation of identity and purity on every lot.

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  • Blarcamesine

    Sigma-1 receptor agonist and mixed muscarinic receptor modulator (aminotetrahydrofuran derivative)

    An orally bioavailable aminotetrahydrofuran derivative developed by Anavex Life Sciences as a sigma-1 receptor agonist with muscarinic receptor co-activity, investigated for disease modification in Alzheimer’s disease, Rett syndrome, Parkinson’s disease dementia, and other neurodegenerative and neurodevelopmental conditions.

    Abstract

    Blarcamesine (ANAVEX 2-73; tetrahydro-N,N-dimethyl-2,2-diphenyl-3-furanmethanamine) is a small-molecule sigma-1 receptor (SIGMAR1) agonist and mixed muscarinic acetylcholine receptor modulator that has advanced through Phase 2b/3 clinical development for early Alzheimer’s disease, Phase 3 for adult Rett syndrome, Phase 2 for Parkinson’s disease dementia, and Phase 2/3 for pediatric Rett syndrome. The compound was first characterized pharmacologically by Villard, Espallergues, Keller, Vamvakides, and Maurice (2011) as a novel aminotetrahydrofuran derivative with anti-amnesic and neuroprotective activity mediated through dual engagement of sigma-1 and muscarinic acetylcholine receptors. The sigma-1 receptor is an endoplasmic reticulum chaperone protein localized at mitochondria-associated endoplasmic reticulum membranes (MAMs) that modulates calcium homeostasis, endoplasmic reticulum stress responses, mitochondrial function, autophagy, and neuroinflammation. Activation of SIGMAR1 by blarcamesine restores cellular proteostasis, reduces oxidative stress through suppression of reactive oxygen species, and promotes neuroplasticity through downstream modulation of brain-derived neurotrophic factor and glutamate signaling. In preclinical models, blarcamesine has demonstrated anti-amnesic activity in scopolamine- and dizocilpine-induced learning impairment paradigms, neuroprotection in the amyloid-beta(25-35) peptide injection mouse model of Alzheimer’s disease (blocking both cognitive impairment and hippocampal oxidative stress), amelioration of motor, sensory, and autonomic phenotypes in the Mecp2 mouse model of Rett syndrome, and dose-dependent sigma-1 receptor occupancy confirmed by positron emission tomography with the selective ligand [18F]FTC-146. The pivotal ANAVEX2-73-AD-004 Phase 2b/3 randomized, double-blind, placebo-controlled trial enrolled 508 patients with early Alzheimer’s disease across 52 centers in five countries and demonstrated that oral blarcamesine at 50 mg and 30 mg daily significantly slowed cognitive decline on the primary endpoint ADAS-Cog13 at 48 weeks (38.5% and 34.6% slowing versus placebo, respectively; P = 0.021 and P = 0.026) [1]. Co-primary analysis showed significant benefit on CDR-SB. Volumetric magnetic resonance imaging demonstrated significant reduction of whole brain atrophy by 37.6%, total grey matter atrophy by 63.5%, and lateral ventricular enlargement by 25.1% versus placebo. Plasma amyloid-beta 42/40 ratio increased significantly in the blarcamesine group (P = 0.048). Open-label extension data through four years of continuous treatment demonstrated sustained benefit on ADAS-Cog13 and ADCS-ADL, with a delayed-start analysis suggesting importance of early treatment initiation. The AVATAR Phase 3 trial in 33 adult patients with Rett syndrome (MECP2 mutation-positive) met primary (RSBQ AUC, P = 0.037; Cohen’s d = 1.91) and secondary (ADAMS, P = 0.010; CGI-I, P = 0.037) efficacy endpoints on once-daily oral dosing of up to 30 mg [2]. A proof-of-concept Phase 2 trial in 132 patients with Parkinson’s disease dementia showed dose-dependent cognitive improvement on the CDR computerized assessment system and improvement on MDS-UPDRS total score at 14 weeks [3]. The EXCELLENCE Phase 2/3 pediatric Rett syndrome trial in 92 patients showed numerical improvement in RSBQ but did not achieve statistical separation from placebo, possibly due to a high placebo response rate [4]. The safety profile across clinical programs is characterized by predominantly mild-to-moderate adverse events concentrated during the initial dose titration period. The most common treatment-emergent adverse events are dizziness (approximately 36% of treated patients in the Alzheimer’s disease program), confusional state (approximately 14%), balance disorder, and fatigue; these are generally transient (resolving within 7 to 11 days), manageable by titration schedule adjustment, and not associated with serious or life-threatening sequelae. No neuroimaging-related adverse events (such as amyloid-related imaging abnormalities) have been reported. Long-term safety data through four years of continuous dosing have not revealed new safety signals. The European Medicines Agency accepted a Marketing Authorization Application for blarcamesine in Alzheimer’s disease in December 2024, but the Committee for Medicinal Products for Human Use issued a negative opinion in December 2025 on grounds of insufficient demonstration of efficacy in patients without SIGMAR1 gene mutations and concerns regarding tolerability-driven treatment discontinuation. The application was subsequently withdrawn in March 2026. This monograph reviews the chemistry, structural class, and synthesis of blarcamesine; the sigma-1 receptor and muscarinic receptor pharmacology; the pharmacokinetic profile including the ANAVEX19-144 metabolite; the preclinical evidence base across Alzheimer’s, Rett syndrome, fragile X syndrome, and Parkinson’s disease models; the full clinical evidence base; sourcing considerations; reconstitution and handling; stack interactions; adverse events; and a comparative assessment of five sigma-1 receptor-active compounds against blarcamesine on five competency standards.

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  • LM22A-4

    Small-molecule TrkB partial agonist and BDNF loop-domain mimetic

    A synthetic tris(hydroxyethyl) benzenetricarboxamide identified by in silico pharmacophore screening as a sub-nanomolar partial agonist of the TrkB neurotrophin receptor, distinguished by neuroprotective efficacy comparable to BDNF in rodent models of Huntington disease, Rett syndrome, traumatic brain injury, and demyelinating injury, with administration predominantly via the intranasal route owing to limited systemic blood-brain barrier penetration.

    Abstract

    LM22A-4, a synthetic 1-N,3-N,5-N-tris(2-hydroxyethyl)benzene-1,3,5-tricarboxamide of molecular weight 339.34 g/mol, is a small-molecule partial agonist of tropomyosin receptor kinase B (TrkB) originally identified in 2010 by Massa, Yang, Bhatt, and Longo through in silico pharmacophore screening of commercial chemical libraries against a model of the loop II domain of brain-derived neurotrophic factor (BDNF) [1]. The compound activates TrkB-dependent signaling cascades (phospho-TrkB, phospho-Akt, phospho-ERK1/2) in hippocampal and striatal neurons with a functional EC50 of 200 to 500 picomolar for TrkB activation and an IC50 of 47 nanomolar for competitive displacement of BDNF from the TrkB extracellular domain, producing neuronal survival at 80 to 90 percent of maximal BDNF efficacy in fetal hippocampal neuron assays [1]. The compound is approximately 98 percent smaller than the 27 kDa BDNF homodimer, is freely water-soluble, and is stable in aqueous solution at neutral pH, properties that make it operationally attractive as a research tool for investigating TrkB-dependent neurotrophic signaling in vitro and in vivo. A substantial preclinical literature, principally from the laboratories of Frank Longo and Stephen Massa at Stanford University and the University of California San Francisco, has demonstrated that LM22A-4 prevents neuronal degeneration with efficacy comparable to BDNF in multiple in vitro disease models, including amyloid-beta-induced hippocampal neuron death, MPP+-induced dopaminergic cell death (a Parkinson disease model), and quinolinic acid-induced striatal neuron death (a Huntington disease model) [1]. In vivo, LM22A-4 administered intranasally or by combined intraperitoneal and intranasal routes activates TrkB signaling in mouse hippocampus and striatum and produces functional benefit in rodent models of Huntington disease (R6/2 and BACHD transgenic mice) [2], Rett syndrome (MeCP2 mutant mice) [3, 4], pediatric and adult traumatic brain injury [5, 6], spinal cord injury [7], ischemic stroke [8], demyelinating injury (cuprizone model) [9], and nonarteritic anterior ischemic optic neuropathy [10]. The Huntington disease work by Simmons et al. (2013) demonstrated correction of striatal TrkB signaling deficits, reduction of intranuclear huntingtin aggregates, preservation of medium spiny neuron dendritic spine density, and improvement of motor function across both acute (R6/2) and chronic (BACHD) transgenic models at brain concentrations exceeding the in vitro neuroprotective dose [2]. The Rett syndrome work demonstrated acute reversal of spontaneous apneas and respiratory dysregulation in MeCP2-null and heterozygous mice, with 4-week treatment restoring wild-type breathing frequency and TrkB phosphorylation in medullary and pontine respiratory nuclei [3, 4]. A critical pharmacological limitation is poor blood-brain barrier penetration following systemic administration, which has necessitated intranasal delivery for central nervous system applications in essentially all published in vivo studies [1, 2]. The intranasal route bypasses the blood-brain barrier through olfactory and trigeminal nerve pathways, achieving cerebrospinal fluid and brain parenchymal concentrations sufficient for TrkB activation, but poses translational challenges for clinical development. A second limitation, identified by Bai et al. (2010) and extended by Todd et al. (2014) and subsequent investigations, is mechanistic complexity: multiplex quantitative assays suggest that LM22A-4 may not activate TrkB through direct orthosteric agonism but rather through indirect transactivation mediated by an unidentified G-protein coupled receptor and Src-family kinase (most likely Fyn) signaling [11, 12]. Despite this mechanistic debate, TrkB-dependence of the in vivo effects has been confirmed through conditional oligodendroglial TrkB deletion studies [9], and the functional neuroprotective and neuroregenerative outcomes are reproducible across laboratories and disease models. The compound has not entered human clinical trials as of the most recent monograph revision. It is supplied by multiple research chemical vendors at greater than 98 percent purity and is used exclusively as a research tool. This monograph reviews the chemistry, pharmacophore-based discovery, receptor pharmacology (including the transactivation controversy), pharmacokinetic limitations, the preclinical evidence base across all studied indications, sourcing and handling considerations, stack interactions, adverse-event signal, and a comparative assessment of five alternative TrkB/neurotrophin receptor ligands against LM22A-4 on five competency standards.

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  • Afobazole

    Plain-language summaryIntrigue 68 / 100

    Afobazole is a Russian anxiolytic that works through sigma-1 and other receptors rather than the GABA system. It is approved in Russia for generalized anxiety without sedation or dependence. Not stocked by Kodiac. This monograph is provided for research and educational reference.

    Intrigue 0–100 blends mechanism novelty, evidence strength, and translational potential. Kodiac editorial, not peer-reviewed.

    Selective non-benzodiazepine anxiolytic with sigma-1 receptor chaperone agonism and multi-target neuroprotective activity

    A 2-mercaptobenzimidazole derivative developed at the V.V. Zakusov Research Institute of Pharmacology and registered in Russia as a non-sedating anxiolytic, distinguished from benzodiazepines by absence of dependence liability and from buspirone by sigma-1 receptor chaperone agonism as the principal molecular mechanism.

    Abstract

    Afobazole (INN fabomotizole; development code CM-346; CAS 173352-21-1) is a 2-mercaptobenzimidazole anxiolytic synthesized and pharmacologically characterized at the V.V. Zakusov Research Institute of Pharmacology of the Russian Academy of Medical Sciences under the direction of Academician S.B. Seredenin. The compound was registered in the Russian Federation in 2006 for the treatment of generalized anxiety disorder and adjustment disorders, and was assigned the International Nonproprietary Name fabomotizole by the World Health Organization in 2012. Structurally, afobazole is 5-ethoxy-2-[2-(morpholino)-ethylthio]benzimidazole, a synthetic benzimidazole bearing a thioether-linked morpholine side chain and an ethoxy substituent on the aromatic ring. The molecular formula is C15H21N3O2S (free base, molecular weight 307.41 g/mol), and the compound is supplied pharmaceutically as the dihydrochloride salt (C15H23Cl2N3O2S, molecular weight 380.33 g/mol).

    The pharmacological profile of afobazole is multi-target. Radioligand binding studies have identified the sigma-1 receptor chaperone protein (Sigma1R; Ki approximately 5.9 micromolar), NRH:quinone reductase 2 (NQO2, also designated the MT3 melatonin binding site; Ki approximately 0.97 micromolar), monoamine oxidase A (MAO-A regulatory site; Ki approximately 3.6 micromolar), and the melatonin MT1 receptor (Ki approximately 16 micromolar) as the principal molecular targets [1, 2]. The sigma-1 receptor interaction is the best-characterized mechanism: afobazole acts as a Sigma1R agonist, promoting dissociation of the Sigma1R-BiP complex at the endoplasmic reticulum membrane and downstream modulation of calcium signaling, inositol 1,4,5-trisphosphate receptor function, and expression of neurotrophic factors including nerve growth factor and brain-derived neurotrophic factor [3, 4]. The anxiolytic effect is blocked by selective Sigma1R antagonists (BD-1047, NE-100) in rodent behavioral models, confirming the dependence of the therapeutic activity on Sigma1R engagement [5, 6]. Unlike benzodiazepines, afobazole does not produce sedation, myorelaxation, amnesia, tolerance, physical dependence, or withdrawal syndrome at therapeutic doses, a profile confirmed in both preclinical and clinical studies [7, 8].

    Pharmacokinetics are characterized by rapid oral absorption (Tmax approximately 0.85 hours), pronounced first-pass hepatic metabolism (oral bioavailability approximately 44 percent), and a short plasma elimination half-life (approximately 0.82 hours) [9]. Despite the short systemic half-life, the anxiolytic effect persists substantially beyond the plasma residence of the parent compound, a pharmacodynamic feature attributed to the slow dissociation kinetics of the Sigma1R chaperone complex and to the sustained expression of downstream neurotrophic mediators. The recommended therapeutic dose is 30 mg per day in three divided administrations of 10 mg, with clinical effect emerging after 5 to 7 days of continuous dosing and maximal effect at 4 weeks [8, 10].

    The clinical evidence base comprises several Russian multicenter trials. The principal registration study was a randomized, double-blind, active-controlled trial of 150 patients with generalized anxiety disorder or adjustment disorders comparing afobazole (30 mg/day) to diazepam (30 mg/day) for 30 days; afobazole produced greater reduction in Hamilton Anxiety Rating Scale total score than diazepam (mean difference 2.93 points; p = 0.01), with 15 adverse events in the afobazole group versus 199 in the diazepam group, and no withdrawal syndrome on discontinuation [8]. Additional studies have evaluated afobazole in somatoform disorders, irritable bowel syndrome, premenstrual syndrome, alcohol withdrawal, and tobacco cessation, with consistent evidence of anxiolytic efficacy and favorable tolerability [10, 11, 12].

    Preclinical research has extended the pharmacological profile well beyond anxiolysis. Afobazole produces Sigma1R-dependent neuroprotection in rat models of ischemic stroke (middle cerebral artery occlusion), with reduced infarct volume and improved neurological outcomes when administered up to 24 hours post-occlusion [13, 14]. In the 6-hydroxydopamine mouse model of Parkinson’s disease, afobazole at 2.5 mg/kg intraperitoneally for 14 days restored striatal dopamine content, preserved tyrosine hydroxylase-positive neurons in the substantia nigra, and normalized motor coordination; these effects were abolished by the Sigma1R antagonist BD-1047 [15, 16]. Cardioprotective activity has been demonstrated in models of isoproterenol-induced myocardial injury, chronic heart failure, and alcoholic cardiomyopathy, with attenuation of pathological remodeling, preserved inotropic function, and reduced brain natriuretic peptide levels [17, 18, 19]. Angiogenic effects have also been reported [20].

    This monograph reviews the chemistry, synthesis, and structural class of afobazole; the multi-target molecular pharmacology with emphasis on the Sigma1R chaperone mechanism; the comprehensive pharmacokinetic profile; the preclinical pharmacology across anxiolytic, neuroprotective, cardioprotective, and anti-inflammatory models; the clinical evidence base in anxiety and related disorders; sourcing and quality considerations; reconstitution and handling; stack interactions; adverse events and safety signal; and a comparative assessment of five non-benzodiazepine anxiolytic candidates (buspirone, hydroxyzine, pregabalin, etifoxine, selank) against afobazole on five competency standards (novelty, effect size, promising potential, side-effect profile, and overall validation). The compound is not approved by the United States Food and Drug Administration or the European Medicines Agency. It is registered in the Russian Federation and is available as an over-the-counter pharmaceutical product within that jurisdiction and as a research-grade preparation from international chemical suppliers.

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  • MitoTEMPO

    Mitochondria-targeted nitroxide antioxidant and superoxide dismutase mimetic

    A triphenylphosphonium-conjugated piperidine nitroxide developed as a mitochondria-selective superoxide scavenger, distinguished from conventional antioxidants by its several-hundred-fold accumulation in energized mitochondria and its established preclinical efficacy across cardiovascular, renal, hepatic, and neurological models of oxidative injury.

    Abstract

    MitoTEMPO (2-(2,2,6,6-tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl)triphenylphosphonium chloride) is a mitochondria-targeted superoxide dismutase (SOD) mimetic that combines the piperidine nitroxide TEMPO radical with a lipophilic triphenylphosphonium (TPP+) cation. The TPP+ moiety exploits the large negative-inside mitochondrial membrane potential (approximately 150 to 180 mV) to drive electrophoretic accumulation of the compound across the inner mitochondrial membrane, achieving intramitochondrial concentrations several hundred-fold greater than extracellular concentrations in energized cells [1, 2]. Once localized to the mitochondrial matrix, the nitroxide radical undergoes a catalytic cycle between its oxidized (nitroxide) and reduced (hydroxylamine) forms, dismuting superoxide to hydrogen peroxide and molecular oxygen in a reaction that functionally mimics manganese superoxide dismutase (MnSOD, SOD2) [3]. This SOD-mimetic activity is complemented by alkyl radical scavenging capacity, enabling MitoTEMPO to interrupt lipid peroxidation chain reactions within the mitochondrial inner membrane. The compound was first characterized in a cardiovascular context by Dikalova, Dikalov, and colleagues at Emory University in a 2010 Circulation Research report demonstrating that MitoTEMPO attenuated angiotensin II-induced hypertension in mice at doses 1000-fold lower than the non-targeted parent compound TEMPOL, reduced mitochondrial and total cellular superoxide, restored vascular nitric oxide bioavailability, and improved endothelial-dependent relaxation [1]. This seminal study established MitoTEMPO as a pharmacological tool for dissecting the contribution of mitochondrial reactive oxygen species (mtROS) to disease pathogenesis and stimulated a broad preclinical literature now spanning hypertension, heart failure, ischemia-reperfusion injury, doxorubicin cardiotoxicity, diabetic nephropathy, acetaminophen hepatotoxicity, hepatocarcinogenesis, sepsis-associated acute kidney injury, noise-induced hearing loss, radiation injury, neurodegenerative disease models, and chronic pain. MitoTEMPO has not entered human clinical trials. No regulatory authority has approved it for therapeutic use. The compound remains a research-grade tool, supplied by multiple chemical vendors (Sigma-Aldrich, Cayman Chemical, Selleckchem, MedChemExpress, others) at greater than 98 percent purity by HPLC. Its physicochemical profile is favorable for in vitro and in vivo research: molecular weight 510.03 g/mol (chloride salt), freely soluble in water and dimethyl sulfoxide, stable as a dry powder at minus 20 degrees Celsius for at least three years, and amenable to intraperitoneal, intravenous, and subcutaneous administration in rodent models at doses typically ranging from 0.7 to 10 mg/kg/day. Formal pharmacokinetic studies characterizing oral bioavailability, plasma half-life, and metabolic disposition in any species have not been published; the preclinical literature relies on functional endpoints (superoxide reduction, blood pressure attenuation, organ protection) rather than on classical pharmacokinetic parameters. This monograph reviews the chemistry, synthesis, and structural class of MitoTEMPO; the SOD-mimetic and radical-scavenging mechanism in molecular detail; the available pharmacokinetic and biodistribution data; the preclinical pharmacology across cardiovascular, renal, hepatic, neurological, and inflammatory models; the absence of clinical evidence; sourcing and quality verification; reconstitution and handling; stack interactions with other mitochondria-targeted agents and redox-active compounds; adverse events and safety signals from animal studies; and a comparative assessment of five mitochondria-targeted antioxidant candidates (MitoQ, elamipretide/SS-31, SkQ1, MitoVitE, TEMPOL) against MitoTEMPO on five competency standards (novelty, effect size, promising potential, side-effect profile, and overall validation).

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  • 7,8-Dihydroxyflavone

    Naturally occurring flavone and selective small-molecule tropomyosin receptor kinase B (TrkB) agonist with BDNF-mimetic neurotrophic activity

    A naturally occurring dihydroxylated flavone identified through cell-based TrkB receptor screening as the first orally bioactive small-molecule brain-derived neurotrophic factor mimetic, distinguished by selective TrkB agonism, blood-brain barrier penetration, and broad preclinical neuroprotective and procognitive efficacy across neurodegenerative, neuropsychiatric, and metabolic disease models.

    Abstract

    7,8-Dihydroxyflavone (7,8-DHF), also designated tropoflavin, is a naturally occurring flavone first isolated from the leaves of Godmania aesculifolia and subsequently identified in Tridax procumbens, Primula vulgaris, and other plant species. The compound was characterized in 2010 by Jang et al. at Emory University as the first orally bioactive, blood-brain-barrier-penetrant small-molecule agonist of the tropomyosin receptor kinase B (TrkB), the principal high-affinity signaling receptor for brain-derived neurotrophic factor (BDNF) [1]. 7,8-DHF binds the extracellular domain of TrkB with a dissociation constant of approximately 320 nM by filter binding assay and approximately 15.4 nM by surface plasmon resonance, triggering receptor dimerization, autophosphorylation at tyrosine residues 706/707, and activation of the downstream PI3K/Akt and MAPK/ERK signaling cascades that mediate neuronal survival, synaptic plasticity, and long-term potentiation [1, 2]. The compound displays selectivity for TrkB over the related neurotrophin receptors TrkA and TrkC and does not activate TrkB kinase-dead mutants, confirming that the phosphorylation signal arises from the receptor itself rather than from off-target tyrosine kinases [2].

    Pharmacokinetic characterization in rodents reveals oral bioavailability of approximately 4.6 percent, a plasma half-life of approximately 134 minutes, rapid brain penetration with peak brain concentrations at 10 minutes after oral dosing, and primary hepatic metabolism through glucuronidation, sulfation, and catechol-O-methyltransferase-mediated methylation [3, 4]. The O-methylated metabolites (7-methoxy-8-hydroxyflavone and 7-hydroxy-8-methoxyflavone) retain TrkB agonist activity in vitro and in vivo, extending the effective pharmacodynamic window beyond the parent compound [5]. The modest oral bioavailability prompted the development of the prodrug R13 (a carbamate ester derivative) by the Ye laboratory, which increases oral bioavailability to approximately 10.5 percent and extends the plasma half-life to approximately 220 minutes [6]. R13 has entered Phase 1 clinical evaluation for Alzheimer’s disease, representing the most advanced clinical translation of TrkB agonist pharmacology from this scaffold.

    Preclinical pharmacology is extensive. In Alzheimer’s disease models, 7,8-DHF reduces BACE1 elevation, decreases amyloid-beta deposition, restores hippocampal synaptic density, and rescues spatial and working memory deficits in 5XFAD, APP/PS1, and Tg2576 transgenic mice at oral doses of 5 mg/kg/day [7, 8, 9]. In Parkinson’s disease models, the compound protects dopaminergic neurons from MPTP- and rotenone-induced degeneration and improves motor function [10]. In depression models, 7,8-DHF reverses learned helplessness, chronic mild stress, and social defeat stress phenotypes through restoration of hippocampal and prefrontal cortical TrkB-BDNF signaling [11, 12]. Additional preclinical efficacy has been demonstrated in models of Huntington’s disease, amyotrophic lateral sclerosis, traumatic brain injury, post-traumatic stress disorder, Rett syndrome, fragile X syndrome, retinal ganglion cell degeneration, and diet-induced obesity [13, 14, 15, 16, 17, 18, 19].

    Safety characterization in chronic rodent studies at 5 mg/kg/day for periods up to 6 months has revealed no pathological changes in major organs, no hematological abnormalities, and no observable toxicity at doses producing robust TrkB activation [2]. A 7-month oral dosing study in a non-human primate model of Parkinson’s disease similarly reported no toxic reactions [20]. No human clinical trial data for the parent compound 7,8-DHF have been published; clinical development has proceeded through the prodrug R13. This monograph reviews the chemistry, natural sources, and structure-activity relationships of 7,8-DHF; the TrkB receptor pharmacology in molecular and cellular detail; the pharmacokinetic profile including metabolism and prodrug development; the preclinical evidence base across neurodegenerative, neuropsychiatric, and metabolic indications; sourcing and quality verification; reconstitution and handling; stack-interaction considerations; adverse-event and safety characterization; and a comparative assessment of five TrkB-targeted candidates against 7,8-DHF on five competency standards.

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  • CDD-0102

    Selective M1 muscarinic acetylcholine receptor partial agonist of the tetrahydropyrimidine-oxadiazole structural class

    A functionally selective partial agonist at the M1 muscarinic acetylcholine receptor developed at the University of Toledo as a cognitive enhancer and neuroprotective agent for Alzheimer’s disease, distinguished from earlier muscarinic agonists by subtype selectivity, low cholinergic adverse-event burden, and oral bioavailability.

    Abstract

    CDD-0102, the hydrochloride salt of 5-(3-ethyl-1,2,4-oxadiazol-5-yl)-1,4,5,6-tetrahydropyrimidine (designated CDD-0102A in its salt form), is a functionally selective partial agonist at the M1 subtype of the muscarinic acetylcholine receptor developed at the University of Toledo College of Pharmacy under the direction of W.S. Messer Jr. as a candidate therapeutic for Alzheimer’s disease and related cognitive disorders. The compound occupies the orthosteric acetylcholine-binding site of the M1 receptor with partial agonist intrinsic activity sufficient to activate phospholipase C-coupled signaling, stimulate non-amyloidogenic processing of amyloid precursor protein (APP) through alpha-secretase, and enhance cognitive function in rodent models of cholinergic deficit, while exhibiting minimal functional activity at M2, M4, and M5 muscarinic subtypes and only weak activity at M3 receptors. This functional selectivity profile distinguishes CDD-0102 from the first-generation M1-preferring muscarinic agonists (xanomeline, sabcomeline, talsaclidine, cevimeline) that produced dose-limiting cholinergic adverse events (salivation, gastrointestinal disturbance, diaphoresis) attributable to activation of peripheral M2 and M3 receptors, a limitation that terminated or constrained the clinical development of each of those compounds in the Alzheimer’s indication. The pharmacological characterization of CDD-0102 encompasses M1-selective receptor binding, stimulation of soluble APP-alpha (sAPPalpha) secretion from Chinese hamster ovary cells stably expressing human M1 receptors, neuroprotective activity in cell culture, brain penetration following systemic administration in rodents, oral bioavailability, and a favorable acute toxicity profile. In behavioral pharmacology, CDD-0102A administered intraperitoneally at doses of 0.03 to 1.0 mg/kg enhances delayed spontaneous alternation in a four-arm cross maze (a measure of spatial working memory) and facilitates strategy switching between place and visual-cue discriminations (a measure of cognitive flexibility), with both effects following a dose-dependent profile and occurring at doses below the threshold for salivation (approximately 0.3 mg/kg intraperitoneal for the minimum effective salivation dose, with an estimated ED50 for salivation of 2.0 mg/kg). More recent preclinical work has extended the pharmacological profile to autism spectrum disorder models, demonstrating that CDD-0102A attenuates stereotyped motor behaviors (self-grooming, digging) and modulates glutamate efflux in dorsolateral striatum of the BTBR T+ Itpr3tf/J mouse, a model of autism-relevant repetitive behavior and social deficit. The compound advanced through preclinical development with support from the National Center for Advancing Translational Sciences (NCATS) Bridging Interventional Development Gaps (BrIDGs) program, which funded the IND-enabling studies including synthetic scale-up, formulation, pharmacokinetics, and toxicology. An Investigational New Drug (IND) application was filed with the United States Food and Drug Administration, and Phase 1 clinical testing was initiated. Published results from Phase 1 clinical evaluation have not appeared in the peer-reviewed literature as of the most recent monograph revision. The compound is not registered as a marketed medicine in any jurisdiction. This monograph reviews the chemistry, synthesis, and structural class of CDD-0102; the M1 muscarinic receptor pharmacology in molecular and functional detail; the preclinical evidence base across Alzheimer’s disease, cognitive flexibility, and autism-relevant endpoints; the available pharmacokinetic characterization; sourcing and quality verification considerations for research applications; reconstitution and handling; stack-interaction considerations; the adverse-event and safety profile; and a comparative assessment of five M1 muscarinic receptor agonist candidates (xanomeline, sabcomeline, talsaclidine, AF267B, cevimeline) against CDD-0102 on five competency standards (novelty, effect size, promising potential, side-effect profile, and overall validation).

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