Isradipine

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder after Alzheimer's disease, primarily affecting the aging population. Despite the introduction of levodopa in the 1960s and significant progress in managing PD symptoms, no treatment has yet demonstrated neuroprotective efficacy. The complexity and multifactorial nature of PD continue to present substantial therapeutic challenges, prompting researchers to explore alternative approaches such as drug repurposing. This strategy offers a time- and cost-efficient route to drug development. Recent efforts have focused on repurposing agents originally developed for metabolic and other non-neurological disorders. Ongoing research is actively investigating several repurposed drugs originally intended for different conditions, including anti-hypertensives (isradipine, dexmedetomidine), anti-asthmatics (montelukast), phosphodiesterase5 inhibitors (sildenafil), antimicrobials (rifaximin), and various CNS-active agents (aripiprazole, escitalopram, paroxetine, venlafaxine, duloxetine, caffeine). While drug repurposing holds considerable promise, comprehensive preclinical and clinical studies are essential to validate these candidates for PD-specific therapeutic applications. This review aims to provide an in-depth overview of PD, encompassing its pathological and molecular characteristics, and to critically evaluate the current landscape of drug repurposing strategies to develop effective therapies for PD.

Neurodegenerative movement disorders, encompassing conditions such as Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis, represent a significant burden on individuals, families, and healthcare systems globally. Traditional drug discovery approaches for these disorders have encountered challenges, including high costs and lengthy timelines. Drug repurposing has emerged in recent years as a promising approach to expedite the discovery of new treatments by leveraging existing drugs approved for other indications. This review explores the landscape of drug repurposed for neurodegenerative movement disorders, highlighting promising candidates, underlying mechanisms, and clinical implications. The rationale behind repurposing, including the advantages of utilizing existing pharmacological agents with established safety profiles and known pharmacokinetics, along with techniques utilized for repurposing (computational and experimental), have been elaborated. Several studies on the potential of pre-existing drugs such as isradipine, tetracycline, ambroxol, metformin, deferiprone, simvastatin, etc., which have been repurposed for neurodegenerative movement disorders, including Parkinson’s disease, Huntington’s disease, Alzheimer’s disease, Multiple Sclerosis, etc. have been discussed. Further, the current scenario and future prospective of drug repurposing have also been touched upon.