Polyester-based excipients to formulate lipophilic drugs into nanoparticles directly at the bed of the patient
June 5-9, 2018
In recent decades there has been an increased interest in polymeric nanoparticles as drug delivery systems thanks to their several advantages, such as continuous maintenance of drug levels in a therapeutically desirable range, and reduction of harmful side effects. These nano-colloids are generally made up of polyesters as long as they are able to easily degrade into the body. However, NP production is often a process that requires complex microfluidic devices. In addition, expensive purification steps are necessary to eliminate the unloaded drug and the high amount of organic solvent used in the NP production step. In the end, a lyophilization step is general adopted to assure a good shelf-life of the final product. All the above-mentioned steps hamper the cost-effective use of a re-formulation of the same therapeutic agent and, in turn, reduce the availability of these treatments among the patient population. For this reason, in this work, a novel NP production protocol that consists only in the use of a syringe and a needle without the need of subsequent purification and freeze-drying steps has been developed. This has been possible by the optimization of the hydrophilic/lipophilic balance of block-copolymers that are able to directly self-assemble in water. The additional degree of freedom necessary for this optimization was introduced via the synthesis of these materials thorough the combination of the reversible addition-fragmentation chain transfer (RAFT) polymerization and the ring opening polymerization (ROP). The NPs has been used to formulate Trabectedin (ET-743), a widely adopted anticancer therapeutic known for its local adverse effect. The pharmacokinetic behavior, antitumor activity and toxicity of this novel NP-based formulation has been compared to the commercially available formulation Yondelis®. NPs have shown the ability to retain the drug into circulation for a longer time in the blood stream compared to the free ET-743 allowing to considerably reduce the local toxic effects. In addition, the shift of the NP preparation step from a specialist to the final user allows to avoid all the purifications and post-processing steps necessary to assure a good shelf-life of the product. In this way, a ET-743 formulation less toxic than the commercially available Yondelis® can be produced at a competitive price taking also into account that this expensive drug is not lost in any of the NP production steps here adopted. In order to prove the versatility of this novel technology, Paclitaxel (PTX), an anticancer therapeutic that it usually formulated with a toxic surfactant (Chremophor EL), have been also formulated into this NPs. In this way, a novel PTX formulation can be produced at a lower cost compared to the ones already approved and present into the market. In particular, it has shown the same advantage in reduction of the toxicity given by the elimination of the Chremophor EL (e.g in Abraxane® and Genexol®).
Umberto Capasso Palmiero, Massimo Morbidelli, Maurizio D’Incalci, and Davide Moscatelli, "Polyester-based excipients to formulate lipophilic drugs into nanoparticles directly at the bed of the patient" in "Nanotechnology in Medicine II: Bridging Translational in vitro and in vivo Interfaces", Millicent Sullivan, PhD, University of Delaware, USA Josué Sznitman, Dr. Sc., Technion-Israel Institute of Technology, Israel Lola Eniola-Adefeso, PhD, University of Michigan, USA Srivatsan Kidambi, PhD, University of Nebraska - Lincoln, USA Eds, ECI Symposium Series, (2018). http://dc.engconfintl.org/nanotech_med_ii/4