Discovery of XL01126: A Potent, Fast, Cooperative, Selective, Orally Bioavailable, and Blood-Brain Barrier Penetrant PROTAC Degrader of Leucine-Rich Repeat Kinase 2.

Leucine-rich repeat kinase 2 (LRRK2) is one of the most promising targets for Parkinson's disease. LRRK2-targeting strategies have primarily focused on type 1 kinase inhibitors, which, however, have limitations as the inhibited protein can interfere with natural mechanisms, which could lead to undesirable side effects. Herein, we report the development of LRRK2 proteolysis targeting chimeras (PROTACs), culminating in the discovery of degrader XL01126, as an alternative LRRK2-targeting strategy. Initial designs and screens of PROTACs based on ligands for E3 ligases von Hippel-Lindau (VHL), Cereblon (CRBN), and cellular inhibitor of apoptosis (cIAP) identified the best degraders containing thioether-conjugated VHL ligand VH101. A second round of medicinal chemistry exploration led to qualifying XL01126 as a fast and potent degrader of LRRK2 in multiple cell lines, with DC50 values within 15-72 nM, Dmax values ranging from 82 to 90%, and degradation half-lives spanning from 0.6 to 2.4 h. XL01126 exhibits high cell permeability and forms a positively cooperative ternary complex with VHL and LRRK2 (α = 5.7), which compensates for a substantial loss of binary binding affinities to VHL and LRRK2, underscoring its strong degradation performance in cells. Remarkably, XL01126 is orally bioavailable (F = 15%) and can penetrate the blood-brain barrier after either oral or parenteral dosing in mice. Taken together, these experiments qualify XL01126 as a suitable degrader probe to study the noncatalytic and scaffolding functions of LRRK2 in vitro and in vivo and offer an attractive starting point for future drug development.

The Lisbon Supramolecular Green Story: Mechanochemistry towards New Forms of Pharmaceuticals.

This short review presents and highlights the work performed by the Lisbon Group on the mechanochemical synthesis of active pharmaceutical ingredients (APIs) multicomponent compounds. Here, we show some of our most relevant contributions on the synthesis of supramolecular derivatives of well-known commercial used drugs and the corresponding improvement on their physicochemical properties. The study reflects, not only our pursuit of using crystal engineering principles for the search of supramolecular entities, but also our aim to correlate them with the desired properties. The work also covers our results on polymorphic screening and describes our proposed alternatives to induce and maintain specific polymorphic forms, and our approach to avoid polymorphism using APIs as ionic liquids. We want to stress that all the work was performed using mechanochemistry, a green advantageous synthetic technique.

Targeting leucine-rich repeat kinase 2 (LRRK2) for the treatment of Parkinson's disease.

Leucine-rich repeat kinase 2 (LRRK2) is a serine-threonine kinase involved in multiple cellular processes and signaling pathways. LRRK2 mutations are associated with autosomal-inherited Parkinson's disease (PD), and evidence suggests that LRRK2 pathogenic variants generally increase kinase activity. Therefore, inhibition of LRRK2 kinase function is a promising therapeutic strategy for PD treatment. The search for drug-like molecules capable of reducing LRRK2 kinase activity in PD led to the design of selective LRRK2 inhibitors predicted to be within the CNS drug-like space. This review highlights the journey that translates chemical tools for interrogating the role of LRRK2 in PD into promising drug candidates, addressing the challenges in discovering selective and brain-penetrant LRRK2 modulators and exploring the structure-activity relationship of distinct LRRK2 inhibitors.

Enhanced cytotoxicity of prenylated chalcone against tumour cells via disruption of the p53-MDM2 interaction.

AIM: Chalcones are naturally occurring compounds with recognized anticancer activity. It was recently shown that the O-prenyl derivative (2) of 2'-hydroxy-3,4,4',5,6'-pentamethoxychalcone (1) had a remarkably increased cytotoxicity against human tumour cells compared to its precursor. With this study, we aimed to investigate the molecular mechanism underlying the improved tumour cytotoxicity of prenylchalcone 2. MAIN METHODS: The impact of chalcones 1 and 2 on p53-MDM2 interaction was investigated using yeast growth-inhibitory and p53 transactivation assays. Their tumour growth-inhibitory effects were assessed on human colon adenocarcinoma HCT116 cell lines with wild-type p53 and its p53-null derivative, followed by analysis of cell cycle and apoptosis. In tumour cells, the activation of a mitochondrial pathway was checked by analysis of reactive oxygen species generation, Bax mitochondrial translocation and cytochrome c release. Additionally, the up-regulation of p53 transcriptional activity was investigated through Western blot analysis of p53 target expression levels, and the disruption of the p53-MDM2 interaction was confirmed by co-immunoprecipitation. KEY FINDINGS: The potent cell tumour growth-inhibitory activity of prenylchalcone 2 was associated with the activation of a p53 pathway involving cell cycle arrest and a mitochondria-dependent apoptosis. Furthermore, a correlation between the distinct cytotoxicity of chalcones 1 and 2 and their ability to disrupt the p53-MDM2 interaction was established. SIGNIFICANCE: This work shows that prenylation is a determinant factor for the enhancement of chalcones tumour cytotoxicity by improving their ability to disrupt the p53-MDM2 interaction. Prenylchalcone 2 represents a starting basis for the design of new p53-MDM2 interaction inhibitors with improved antitumor properties.

New forms of old drugs: improving without changing.

OBJECTIVES: In a short approach, we want to present the improvements that have recently been done in the world of new solid forms of known active pharmaceutical ingredients (APIs). The different strategies will be addressed, and successful examples will be given. KEY FINDINGS: This overview presents a possible step to overcome the 10-15 years of hard work involved in launching a new drug in the market: the use of new forms of well-known APIs, and improve their efficiency by enhancing their bioavailability and pharmacokinetics. It discusses some of the latest progresses. SUMMARY: We want to present, in a brief overview, what recently has been done to improve the discovery of innovative methods of using well-known APIs, and improve their efficiency. Multicomponent crystal forms have shown to be the most promising achievements to accomplish these aims, by altering API physico-chemical properties, such as solubility, thermal stability, shelf life, dissolution rate and compressibility. API-ionic liquids (ILs) and their advantages will be briefly referred. An outline of what has recently been achieved in metal drug coordination and in drug storage and delivery using bio-inspired metal-organic frameworks (BioMOFs) will also be addressed.