Gene therapy: a turning point for parkinson’s disease?

By Ana Espino | Published on April 7, 2026 | 4 min read


Parkinson’s disease is a major progressive neurodegenerative disorder affecting more than 8.5 million people worldwide. Its incidence continues to rise, making it an increasing public health concern. The disease is characterized by the progressive degeneration of dopaminergic neurons in the substantia nigra, along with the accumulation of α-synuclein aggregates, leading to neuronal dysfunction.  

Clinically, Parkinson’s disease presents with motor symptoms—including bradykinesia, rigidity, and tremor—as well as often disabling non-motor manifestations such as cognitive impairment and sleep disorders. These features reflect the complexity of the underlying pathophysiological mechanisms, which remain only partially understood.  

Current treatments, dominated by levodopa, provide initial symptomatic relief. However, their effectiveness declines over time, with the emergence of motor fluctuations and dyskinesias. Moreover, these approaches do not target the underlying disease mechanisms and have limited impact on non-motor symptoms.  

In this context, there is a critical need for strategies capable of slowing—or even modifying—disease progression. Gene therapy is emerging as an innovative approach aimed at directly targeting the molecular mechanisms involved, including dopamine production, neuroprotection, and reduction of α-synuclein.  

The aim of this review is to analyze recent developments in gene therapy for Parkinson’s disease by evaluating mechanisms of action, clinical outcomes, and limitations, in order to identify future therapeutic perspectives.  

Does gene therapy live up to its promise?  

This review synthesizes data from preclinical studies and clinical trials assessing various gene therapy approaches. These methods primarily rely on viral vectors—particularly AAV, lentivirus, and HSV—to enable targeted gene delivery to the central nervous system.  

Strategies aimed at restoring the dopaminergic system involve introducing genes involved in dopamine synthesis, such as TH, AADC, and GTPCH. Clinical trials have shown improvements in motor scores (UPDRS) and good tolerability, although effects are comparable to placebo in some studies.  

Other approaches target neuronal hyperactivity through the expression of GAD, increasing GABA production. Phase II trials report approximately a 23% improvement in motor scores, confirming a moderate but significant clinical effect.  

Neuroprotection is another major focus, with the administration of trophic factors such as GDNF, NRTN, or CDNF. These strategies increase dopaminergic biomarkers but do not consistently translate into clinical benefit, particularly in patients at advanced stages.  

Therapies targeting genetic mutations—such as PINK1, PRKN, or DJ-1—aim to correct mitochondrial dysfunction. Animal models show functional improvement and significant neuroprotection.  

Restoring lysosomal function via GBA1 represents a promising strategy, reducing α-synuclein accumulation and inflammation, with several clinical trials currently underway.  

Finally, reducing SNCA expression using RNA interference decreases α-synuclein levels and improves symptoms in animal models. However, potential neurotoxicity highlights the need for precise control of gene expression.  

A real hope, still to be confirmed  

Parkinson’s disease remains a complex neurodegenerative condition with no curative treatment to date. Current approaches are largely symptomatic and do not slow disease progression, underscoring the urgent need for strategies targeting underlying pathophysiological mechanisms.  

In this context, this review highlights gene therapy as a particularly promising approach, with observed effects on motor function and certain neurological biomarkers—suggesting potential benefits beyond symptomatic control.  

Nevertheless, several limitations still hinder its clinical application. There is significant variability in patient responses, likely related to disease heterogeneity and stage differences. Technical challenges associated with viral vectors—particularly regarding targeting, safety, and control of gene expression—remain substantial. In addition, the lack of long-term data limits the assessment of sustained efficacy and potential adverse effects.  

Future perspectives rely on the development of combined strategies targeting multiple pathways, as well as optimization of delivery systems to improve precision and safety. Better patient selection, based on genetic and clinical profiles, will also be essential. Ultimately, gene therapy could become a cornerstone of personalized medicine, with the potential to modify the course of Parkinson’s disease.  

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About the author – Ana Espino
PhD in Immunology, specialized in Virology  
As a scientific writer, Ana is passionate about bridging the gap between research and real-world impact. With expertise in immunology, virology, oncology, and clinical studies, she makes complex science clear and accessible. Her mission: to accelerate knowledge sharing and empower evidence-based decisions through impactful communication.