Update on COX-2 inhibitor patents with a focus on optimised formulation and therapeutic scope of drug combinations making use of COX-2 inhibitors

Diaryl-Substituted (Dihydro)pyrrolo[3,2,1-hi]indoles, a Class of Potent COX-2 Inhibitors with Tricyclic Core Structure

A new compound class of diaryl-substituted heterocycles with tricyclic dihydropyrrolo[3,2,1-hi]indole and pyrrolo[3,2,1-hi]indole core structures has been designed and was synthesized by a modular sequence of Friedel-Crafts acylation, amide formation, and McMurry cyclization. This synthesis route represents a novel and versatile access toward dihydropyrrolo[3,2,1-hi]indoles and is characterized by good chemical yields and high modularity. From a set of 19 derivatives, 11 candidates were selected for determination of their COX inhibition potency and were found to be selective inhibitors with high affinity to COX-2 (IC50 ranging from 20-2500 nM and negligible inhibition of COX-1). The binding mode of the novel inhibitors in the active side of COX-2 was calculated in silico using the protein-ligand docking program GOLD by application of the molecular structures of two compounds derived from X-ray crystallography. Two novel compounds with high affinity to COX-2 (6k = 70 nM, 8e = 60 nM) have a fluoro substituent, making them promising candidates for the development of (18)F-radiolabeled COX-2 inhibitors for imaging purposes with positron emission tomography (PET).

Pathogenic Mechanisms and In Vitro Diagnosis of AERD

Aspirin-exacerbated respiratory disease (AERD) refers to chronic rhinosinusitis, nasal polyposis, bronchoconstriction, and/or eosinophilic inflammation in asthmatics following the exposure to nonsteroidal anti-inflammatory drugs (NSAIDs). A key pathogenic mechanism associated with AERD is the imbalance of eicosanoid metabolism focusing on prostanoid and leukotriene pathways in airway mucosa as well as blood cells. Genetic and functional metabolic studies on vital and non-vital cells pointed to the variability and the crucial role of lipid mediators in disease susceptibility and their response to medication. Eicosanoids, exemplified by prostaglandin E(2) (PGE(2)) and peptidoleukotrienes (pLT), are potential metabolic biomarkers contributing to the AERD phenotype. Also other mediators are implicated in the progress of AERD. Considering the various pathogenic mechanisms of AERD, a multitude of metabolic and genetic markers is suggested to be implicated and were introduced as potential biomarkers for in vitro diagnosis during the past decades. Deduced from an eicosanoid-related pathogenic mechanism, functional tests balancing PGE(2) and pLT as well as other eicosanoids from preferentially vital leukocytes demonstrated their applicability for in vitro diagnosis of AERD.

Salicylate intolerance: pathophysiology, clinical spectrum, diagnosis and treatment

INTRODUCTION

Acetylic salicylic acid (aspirin) intolerance relates to altered generation and metabolism of arachidonic acid and eicosanoids, and prostaglandins and leukotrienes ingestion of salicylates or COX-inhibitors.

METHODS

Selective review of literature in PubMed and the Cochrane Library.

RESULTS

Rhinitis, asthma and nasal polyposis are typical presentations, but urticaria and gut inflammation are also described. The mechanism involves a specific reaction to COX inhibitor substances in analgesics, cosmetics or plants resulting in an abnormal pattern of eicosanoids (prostaglandins and leucotrienes). The diagnosis is based on symptoms occurring immediately following ingestion of these substances or on refractory polyp formation. Blood tests may be helpful in unclear cases. Avoidance of triggering agents is helpful. Corticosteroids are the mainstay of pharmacological treatment. Biological, desensitization treatment involving the administration of increasing amounts of acetylic salicylic acid may also be used.

DISCUSSION

Asthma, rhinitis and nasal polyps, as well as chronic gastrointestinal irritation and urticaria following acetylic salicylic acid ingestion may suggest intolerance.