Specialists from the G. A. Krestov Institute of Solution Chemistry (ISC) in Ivanovo have developed an extended-release dosage form, which will allow, for example, taking one pill per day instead of three, the press service of the Russian Ministry of Education and Science reported.
“The scientists at ISC have developed an extended-release dosage form. In simple terms, this means that a patient will not need to take many pills. For instance, instead of taking a medication three times a day, once is sufficient, and the active substance will be slowly absorbed by the body,” noted the press service.
The target substance of the study was riluzole, which slows the progression of amyotrophic lateral sclerosis (ALS). The developer of the drug under the brand name Rilutek is the French company Rhone-Poulenc Rorer, now part of Sanofi. In Russia, riluzole is available as the suspension Teglutik, marketed by the Italian company Italfarmaco.
Pure riluzole has poor water solubility, which limits its bioavailability. The scientists used the substance as a basis for a chemical reaction with salicylic acid, resulting in a new molecular structure where riluzole and salicylate are connected in a single crystal lattice. “We created three crystalline forms, which differ in structure and properties, developed methods for obtaining each of them, and determined how these forms differ from each other and from pure riluzole in terms of water solubility,” said Alexander Voronin, a senior researcher at ISC. It turned out that one of the forms holds the riluzole molecules more tightly, preventing them from dissolving instantly, which allows switching to a once-daily administration.
The technology of “packaging” the active substance is applicable to the class of poorly soluble drugs, which account for about 40% in pharmacology. However, the “auxiliary” molecule can be not only salicylic acid but also other compounds — depending on the chemical properties of the INN.
The prolonged action of drugs will allow patients to avoid missing doses, which often happens due to absent-mindedness or being busy, and thus will contribute to more effective treatment, the authors of the study believe.