Safety of nicergoline as an agent for management of cognitive function disorders

Nicergoline is a semisynthetic ergot derivative and has a selective alpha-1A adrenergic receptor blocking property and also other additional mechanisms of actions, both in the brain and in the periphery. It is in clinical use for over three decades in over fifty countries for conditions such as cerebral infarction, acute and chronic peripheral circulation disorders, vascular dementia, and Alzheimer's disease and has been found to be beneficial in a variety of other conditions. However, concerns about its safety have been raised, especially after the European medicines agency's (EMEA's) restriction in the use of all ergot derivatives including nicergoline. But, most of the available literature and data suggest that the adverse events with nicergoline are mild and transient. Further, none of the available treatment options for cognitive disorders afford definitive resolution of symptoms. In this backdrop, we discuss the pharmacology of nicergoline with special emphasis on the safety of this compound, especially when used in patients suffering from cognitive function disorders.

A systematic review and meta-analysis assessing adverse event profile and tolerability of nicergoline

OBJECTIVE

To evaluate the safety profile of nicergoline compared with placebo and other active agents from published randomised controlled trials.

DESIGN

Systematic review and meta-analysis of nicergoline compared with placebo and other active agents across various indications.

DATA SOURCES

MEDLINE, Medline-in-process, Cochrane, EMBASE, EMBASE alerts, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews (CDSR) and Cochrane Methodology Register (CMR) for all the randomised controlled trials, open-label or blinded, in adults treated with nicergoline. Studies published until August 2013 were included.

REVIEW METHOD

29 studies were included for data extraction. The studies included in this review were majorly from European countries and mostly in cerebrovascular disease (n=15) and dementia (n=8).

RESULTS

The treatment withdrawals were comparatively lower in the nicergoline group as compared with the placebo group (RR=0.92; 95% CI 0.7 to 1.21) and other active comparators (RR=0.45; 95% CI 0.10 to 1.95), but the difference was non-significant. Incidence of any adverse events (AEs) was slightly higher (RR=1.05; 95% CI 0.93 to 1.2) while incidence of serious AEs was lower (RR=0.85; 95% CI 0.50 to 1.45) in the nicergoline compared with placebo group. Frequency of anxiety was significantly lower in nicergoline as compared with placebo (p=0.01). Other AEs including diarrhoea, gastric upset, dizziness and drowsiness were less frequent in the nicergoline group when compared with placebo/active drugs, but the difference was non-significant. Frequency of hypotension and hot flushes was slightly higher in the nicergoline group but the difference was non-significant. None of the studies reported any incidence of fibrosis or ergotism with nicergoline treatment.

CONCLUSIONS

Nicergoline is an ergot derivative, but its safety profile is better than other ergot derivatives like ergotamine and ergotoxine. This systematic review and meta-analysis suggests that nicergoline has a good safety profile. None of the studies included in this systematic review reported any incidence of fibrosis or ergotism with nicergoline.

Therapeutic use of nicergoline

The ergot alkaloid derivative nicergoline became clinically available about 35 years ago in the 1970s. Nicergoline has a broad spectrum of action: (i) as an alpha(1)-adrenoceptor antagonist, it induces vasodilation and increases arterial blood flow; (ii) it enhances cholinergic and catecholaminergic neurotransmitter function; (iii) it inhibits platelet aggregation; (iv) it promotes metabolic activity, resulting in increased utilization of oxygen and glucose; and (v) it has neurotrophic and antioxidant properties. Acting on several basic pathophysiological mechanisms, nicergoline has therapeutic potential in a number of disorders. This article provides an overview of the published clinical evidence relating to the efficacy and safety of nicergoline (30 mg twice daily) in the treatment of dementia (including Alzheimer's disease and vascular dementia) and vascular and balance disorders. For dementia of different aetiologies, the therapeutic benefit of nicergoline has been established, with up to 89% of patients showing improvements in cognition and behaviour. After as little as 2 months of treatment, symptom improvement is apparent compared with placebo, and most patients are still improved or stable after 12 months. Concomitant neurophysiological changes in the brain indicate (after only 4-8 weeks' treatment) improved vigilance and information processing. In patients with balance disorders, mean improvements of 44-78% in symptom severity and quality of life have been observed with nicergoline. Although clinical experience with nicergoline in vascular disorders is limited to relatively short-term, small-scale studies, it has been successfully used in rehabilitation therapy of patients with chronic ischaemic stroke. Open-label evaluations suggest that nicergoline may also be valuable in glaucoma, depression and peripheral arterio-pathy. Adverse events of nicergoline, if any, are related to the central nervous system, the metabolic system and the overall body. Most are considered typical symptoms of ergot derivatives. Because of their generally mild and transient nature, treatment discontinuations occur relatively infrequently. The efficacy of nicergoline combined with a favourable safety and tolerability profile at commonly applied doses (60 mg/day) make this agent a valuable therapy in patients with mild to moderate dementia, vascular diseases and balance disorders.