Neurotoxins and Drugs for the Treatment of Parkinson's Disease. Part I: Neurotoxins, Levodopa, and Agents Influencing Dopamine Metabolism (A Review)

Discovery of 5-{4-[(7-Ethyl-6-oxo-5,6-dihydro-1,5-naphthyridin-3-yl)methyl]piperazin-1-yl}-N-methylpyridine-2-carboxamide (AZD5305): A PARP1-DNA Trapper with High Selectivity for PARP1 over PARP2 and Other PARPs

Poly-ADP-ribose-polymerase (PARP) inhibitors have achieved regulatory approval in oncology for homologous recombination repair deficient tumors including BRCA mutation. However, some have failed in combination with first-line chemotherapies, usually due to overlapping hematological toxicities. Currently approved PARP inhibitors lack selectivity for PARP1 over PARP2 and some other 16 PARP family members, and we hypothesized that this could contribute to toxicity. Recent literature has demonstrated that PARP1 inhibition and PARP1-DNA trapping are key for driving efficacy in a BRCA mutant background. Herein, we describe the structure- and property-based design of 25 (AZD5305), a potent and selective PARP1 inhibitor and PARP1-DNA trapper with excellent in vivo efficacy in a BRCA mutant HBCx-17 PDX model. Compound 25 is highly selective for PARP1 over other PARP family members, with good secondary pharmacology and physicochemical properties and excellent pharmacokinetics in preclinical species, with reduced effects on human bone marrow progenitor cells in vitro.

In silico search for an endogenous anti-Alzheimer’s molecule — Screening amino acid metabolic pathways

Alzheimer’s disease (AD) is a neurodegenerative disorder arising from abnormal aggregation of β-amyloid (Aβ) and progressing at different rates from person to person. There may exist endogenous compounds within the brain that play a role in inhibiting aggregation. We have devised a unique in silico screening strategy of endogenous molecules within the human brain, with special emphasis on amino acid metabolic pathways, to identify compounds with the potential to inhibit Aβ aggregation. Metabolites of tryptophan were computationally identified through this screening as potential therapeutics and were optimized via molecular modelling to determine their capacity to bind to Aβ. The most successful molecule identified was 3-hydroxyanthranilic acid (3-HAA). This endogenous molecule was then computationally explored to design novel analogues of 3-HAA with the goal of improving Aβ antiaggregant activity. These combined in silico methods of screening, identifying, and successfully “analoguing” an endogenous molecule of the brain as an AD therapeutic has yielded positive results and a novel approach to computer-aided drug design.