Design, synthesis, and preliminary evaluation of gabapentin-pregabalin mutual prodrugs in relieving neuropathic pain

Abstract

As a part of a program for the development of specific analgesics in relieving neuropathic pain, the purpose of the present study was to investigate a new concept that involves the conjugation of two drugs, gabapentin and pregabalin, as mutual prodrugs using a chemical modification approach. A series of gabapentin-pregabalin diester compounds were synthesized using linear or branch bis-hydroxyl linkers. Their pharmacological properties for treating neuropathic pain were investigated in a rat model of chronic sciatic nerve constriction injury (CCI). In-vivo evaluation demonstrated that 1a and 1b composed of two gabapentin molecules as well as 3a composed of gabapentin and pregabalin with the short linear linker, were effective in reversing tactile allodynia in CCI rats. Compounds with longer or side-branched linkers showed lower efficiencies and severe adverse effects.