Advantages and limitations of renin inhibition with aliskiren

In the current context of renin-angiotensin-aldosterone system (RAAS) blockade, angiotensin (Ang) converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), or their combination, have proved to be effective in providing cardiovascular and renal protection. However, renin inhibition has long been recognized as the preferred site for blockade of the RAAS because renin represents the first, highly-regulated and rate-limiting step of the system. Up to now, the first orally active renin inhibitors initially tested in humans did not meet the necessary all the criteria (specificity, potency, and pharmacokinetic profile) to become clinically useful drugs. The synthesis of aliskiren, a potent alkane carboxamide renin inhibitor, now provides an orally active compound which, according to its pharmacological profile in normotensive subjects and in patients with hypertension, diabetic nephropathy or heart failure suggests that this drug may be of value for the treatment of patients with cardiovascular and renal disorders. However, long-term studies are needed to demonstrate the efficacy of aliskiren in these clinical settings. The results of the Aliskiren Trial in Type 2 Diabetes Using Cardiorenal Disease Endpoints (ALTITUDE) trial which has already included 8600 patients with type 2 diabetes, proteinuria and a high cardiovascular risk and compared the effects of aliskiren vs. a placebo on a composite endpoint including renal and cardiovascular morbidity and mortality should be provided in 2012.     

Interactions entre les cyclodextrines et les triglycérides : de la stabilisation des émulsions à l’obtention d’un nouveau système galénique appelé « billes »

Natural cyclodextrins are cyclic oligosaccharides which can be modified to obtain more water soluble or insoluble derivatives. The main interest of cyclodextrins results from their ability to form an inclusion complex with hydrophobic molecules. Inclusion constitutes a true molecular encapsulation. This property is employed in pharmaceutical industry to facilitate the formulation of poorly water soluble and/or fragile drugs. A more recent application of cyclodextrins consists in their use in the preparation of dispersed systems such as micro- and nanoparticles or even liposomes. When incorporated in dispersed systems, cyclodextrin can enhance drug solubility, drug stability and drug loading. Interestingly, cyclodextrins themselves can also be employed to form or stabilise dispersed systems (material or emulsifying agent). For example, the interactions between cyclodextrins with components of the vegetable oils (more especially with triglycerides) allow to stabilise simple or multiple emulsions but also to form particles called “beads”. Very rich in oil, this novel lipid carrier presents an important potential for the encapsulation of highly lipophilic compounds and their delivery by topical and oral routes. These two applications are more particularly developed in the present paper.