Temporal profile of lymphocyte counts and relationship with infections with fingolimod therapy in paediatric patients with multiple sclerosis: Results from the PARADIGMS study

BACKGROUND

Reduction in absolute lymphocyte count (ALC) is expected with fingolimod treatment.

OBJECTIVE

To evaluate the effect of fingolimod 0.5 mg versus intramuscular interferon β-1a (30 μg) on ALC and its relationship with infections in paediatric-onset multiple sclerosis (POMS) up to 4 years.

METHODS

We assessed ALC at baseline, monthly till 3 months, and every 3 months (core phase) and with variable periodicity (extension phase) of Phase 3 PARADIGMS study (N = 215). Incidence rates (IRs) of infection-related adverse events (^infAEs)/100 patient-years were analysed by on-study nadir ALC.

RESULTS

With fingolimod, ALC rapidly reduced to 29.9%-34.4% of baseline values within 2 weeks and remained stable thereafter; no relevant changes observed with interferon. IRs of ^infAEs were 67.6 with fingolimod and 61.8 with interferon; IR ratios with respect to interferon, overall: 1.09, by nadir ALC 0.2-0.4 × 10⁹/L: 1.13 and >0.4 × 10⁹/L: 0.91. Three patients had a single episode of ALC <0.2 × 10⁹/L (core phase). No opportunistic infections were observed and infection risk did not increase during the extension phase.

CONCLUSION

In paediatric patients, the overall incidence of infections was comparable between fingolimod and interferon. No association was observed between nadir ALC and infections in POMS, although sample size may have been too small to rule an association.

Correction to: Long-Term Effect of Immediate Versus Delayed Fingolimod Treatment in Young Adult Patients with Relapsing-Remitting Multiple Sclerosis: Pooled Analysis from the FREEDOMS/FREEDOMSII Trials

Figures 1a, 1b and 3 were published incorrectly in the original version. The corrected images are given as follows.

Long-Term Effect of Immediate Versus Delayed Fingolimod Treatment in Young Adult Patients with Relapsing-Remitting Multiple Sclerosis: Pooled Analysis from the FREEDOMS/FREEDOMS II Trials

INTRODUCTION

Fingolimod has demonstrated clinical and MRI benefits versus placebo/interferon β-1a in young adults with multiple sclerosis (MS). Here we report the long-term effects of fingolimod 0.5 mg on clinical and MRI outcomes in young adults with MS aged ≤ 30 years followed up for up to 8 years (96 months).

METHODS

This post hoc analysis of pooled FREEDOMS/FREEDOMS II studies included patients who either received fingolimod 0.5 mg from randomization (immediate; N = 163) or switched from placebo to fingolimod at month (M) 24 (delayed; N = 147). The 6-month confirmed disability improvement [6m-CDI: based on Expanded Disability Status Scale (EDSS)], 6m-CDI-plus (6m-CDI+; EDSS, 9-Hole Peg Test, Timed 25-Foot Walk Test), 6-month confirmed disability progression (6m-CDP), time to EDSS score ≥ 4, annualized relapse rates (ARRs), new/newly enlarging T2 (neT2) lesions, and annual rate of brain volume loss (BVL) were analyzed from baseline to M24, M48, and M96. Cox regression and negative binomial regression models were used to analyze measured outcomes.

RESULTS

At baseline, more than two-thirds of young adult patients were treatment naïve, had more than two relapses in the previous 2 years, and EDSS score < 2. From M0 to M96, a significantly higher proportion of young adult patients in the immediate group (vs. delayed group) achieved 6m-CDI (58.2% vs. 30.5%, p = 0.0206) and 6m-CDI+ (70.6% vs. 42.3%, p = 0.0149); significantly fewer patients reached 6m-CDP (20.1% vs. 34.7%, p = 0.0058) and EDSS ≥ 4 (24.1% vs. 34.1%, p = 0.0041). Up to M96, young adults in the immediate versus delayed group had lower ARRs (0.16 vs. 0.38, p < 0.0001) and a higher proportion of patients were free of neT2 lesions at M48 (31.0% vs. 5.0%, p = 0.0011).

CONCLUSION

In young adult patients with MS, immediate versus delayed fingolimod treatment was associated with improved disease outcomes and greater long-term benefits in both disease activity and disability progression.

FUNDING

Novartis Pharma AG.

Clinical review: impact of statin substitution policies on patient outcomes

BACKGROUND

The increasing awareness of cost issues in health care has led to the increasing use of policy-driven substitution of branded for generic medications, particularly relative to statin treatment for cardiovascular diseases. While there are potential short-term health care savings, the consequences for primary care are under-researched. Our objective was to review data on intensive statin therapy and generic substitution in patients at high cardiovascular risk.

RESULTS

Current treatment guidelines for the prevention of cardiovascular disease are consistent in their recommendations regarding statin therapy and treatment targets. Clinical trials demonstrate that to reduce cardiovascular events, a statin is more effective than placebo, intensive statin therapy is more effective than moderate statin therapy in patients with established coronary disease, and in patients receiving intensive statin therapy the lowest risk is associated with the lowest low-density lipoprotein levels. However, in clinical practice, patients at high cardiovascular risk are prone to be undertreated. Observational studies suggest that mandatory statin substitution may increase the gap between achieved and recommended therapeutic targets.

CONCLUSIONS

Substitution of generic statins may be cost-saving, particularly at the primary prevention level. However, statin substitution policies have not been adequately studied on a population level. Data raise concern that mandated statin substitution may lead to unfavourable treatment choices at the level of the individual high-risk patient.

Role of NO and angiotensin II in the early development of endothelial functions impairment and cardiac hypertrophy in deoxycorticosterone acetate-salt hypertension

This study was designed to investigate the effects of chronic inhibition of NO synthesis as well as chronic angiotensin receptor blockade with losartan in the development of hypertension, on mesenteric arterial bed reactivity as well as on the development of cardiac and kidney hypertrophy in deoxycorticosterone-salt (DOCA) hypertension. Uninephrectomized rats were divided in four experimental groups all receiving saline water to drink and treated or not with losartan over a period of 9 days. Two of these groups were administered DOCA, one of which received also N(G)-nitro-L-arginine-methyl ester (L-NAME) to drink. A third group received only L-NAME, while another group received only saline. Systolic blood pressure was similarly increased in L-NAME, DOCA, DOCA-L-NAME groups. Cardiac and kidney weights were increased in DOCA but significantly reduced in DOCA-L-NAME. Losartan prevented the development of hypertension in all groups and also prevented cardiac and kidney hypertrophy in DOCA. The hyperreactivity of mesenteric arteries to phenylephrine, measured in the presence of indomethacin, was endothelium-dependent in both L-NAME groups but not in DOCA rats. Pretreatment with BQ 123 did not modify these endothelium-dependent responses in L-NAME rats. Chronic losartan prevented endothelium-dependent phenylephrine hyperreactivity only in DOCA, whereas only the removal of the endothelium attenuated the responsiveness in both L-NAME-treated groups. Vasorelaxations to acetylcholine and isoproterenol were attenuated in the three hypertensive groups and were normalized only in DOCA and L-NAME treated with losartan. In summary, in all hypertensive groups, blood pressure was normalized by losartan independently of its effects on endothelial functions. In DOCA, losartan normalized the phenylephrine hyperreactivity through an endothelial-dependent mechanism. However, in L-NAME-treated groups an endothelial-derived contracting factor, other than angiotensin II, endothelin, or vasoconstrictor prostanoids, appears to be activated. Both NO and angiotensin II seem to play a role in the early development of hypertension and organ hypertrophy in DOCA hypertension.

[Interaction between the sympathetic and renin-angiotensin system]

The renin-angiotensin system is involved in the control of sodium and water balance, mitogenesis and the regulation of vascular tone as well as of the activity of the sympathetic nervous system. Many of these effects may be regulated at a local level by independent tissue renin-angiotensin systems. The renin-angiotensin and adrenergic nervous systems are cross-regulated by interactive compensatory mechanisms. Therefore, the activation of one of these systems induces the activation or induction of the other leading to a co-amplification of cellular mechanisms, for instance resulting in the facilitation of sympathetic neurotransmission. This paper describes the interactions between these systems in the central nervous system and at pre- and postsynaptic sites of the nerve endings in cardiovascular tissues. Since these systems are cross-regulated, the inhibition of one would attenuate the activity of the other. The drugs that inhibit specifically the various components of the renin-angiotensin system have proved powerful tools for studies of the physiology of this system as well as for the treatment of hypertension and heart failure.

Impaired basal sympathetic tone and alpha1-adrenergic responsiveness in association with the hypotensive effect of melatonin in spontaneously hypertensive rats

Early investigations have suggested a relationship between hypertension and melatonin, a pineal hormone. The aims of this study were to evaluate the implication of the sympathetic nervous system in the acute effect of melatonin on blood pressure in conscious 12-week-old spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY), and to determine whether the hypotensive effect of melatonin is associated with alterations in pre- or postsynaptic mechanisms. Melatonin, 10 mg/kg, produced a sustained time-dependent decrease of mean arterial pressure only in SHR without changes in heart rate in both groups. Until 20 min after melatonin administration, plasma epinephrine (EPI) levels were reduced by about 60% in both groups, but norepinephrine (NE) levels were decreased only in SHR by about 30%. The nitroprusside-induced hypotension responses and the associated increases in heart rate were similar in both groups before or after administration of melatonin. Unexpectedly, the sympathetic reactivity to nitroprusside, evaluated by the increases in NE and EPI, was markedly enhanced after melatonin treatment in both WKY and SHR. The stimulation induced [3H]-norepinephrine release from isolated atria was not altered by melatonin in SHR. In cultured aortic vascular smooth muscle cells, the basal and phenylephrine induced inositol phosphate formations were greater in SHR, and the melatonin pretreatment dose dependently attenuated the phenylephrine responses in cells from both WKY and SHR. Therefore the hypotensive action of melatonin appears to be associated with an inhibition of basal sympathoadrenal tone and could also be mediated partly by the blockade of postsynaptic alpha1-adrenergic receptor-induced inositol phosphate formation.

Sympathetic functions in NG-nitro-L-arginine-methyl-ester-induced hypertension: modulation by the renin-angiotensin system

BACKGROUND

Nitric oxide and angiotensin II have been shown to attenuate cardiac beta-adrenergic inotropism.

OBJECTIVE

To study sympathetic presynaptic and post-synaptic functions after chronic nitric oxide synthesis blockade with NG-nitro-L-arginine-methyl-ester (L-NAME, for 40 days) in association with renin-angiotensin system blockade (during the last 12 days) in order to evaluate the possible physiological interactions between these systems.

METHODS

Haemodynamic parameters in conscious rats were assessed. Release of noradrenaline from isolated atria and cardiac beta-adrenergic-adenylyl cyclase pathway in rats of sham-treated and L-NAME-treated groups, with or without losartan or enalaprilat treatment, were assessed.

RESULTS

L-NAME-treated rats developed a time-dependent increase in blood pressure associated with increased plasma adrenaline levels whereas plasma noradrenaline and cardiac catecholamine levels were similar to those in sham-treated rats. Field-stimulated release of noradrenaline, cardiac beta-adrenoceptor density and affinity and isoproterenol-stimulated formation of cyclic AMP were similar in sham and L-NAME-treated rats. However, Gpp(NH)p, NaF and forskolin-stimulated adenylyl cyclase activity were greater in L-NAME rats although Gs and Gi protein levels were similar in sham-treated and L-NAME-treated rats. Losartan and enalaprilat treatments exerted equipotent angiotensin-pressor response blockade and hypotensive effects whereas catecholamine levels were not altered. Interestingly, only losartan treatment acted to reduce the increased Gs-adenylyl cyclase activity in L-NAME rats, without alteration of G protein levels.

CONCLUSIONS

The nitric oxide synthase blockade-induced hypertension seems to be associated with increased adrenal-medullary system and renin-angiotensin system activities. The increased Gs-adenylyl cyclase activity after chronic inhibition of formation of nitric oxide suggests that nitric oxide plays a modulatory role in formation of cyclic AMP, to which angiotensin II seems to contribute through an angiotensin II type 1 receptor-mediated mechanism.

Effects of renin-angiotensin blockade on sympathetic reactivity and beta-adrenergic pathway in the spontaneously hypertensive rat

As interactions between the renin-angiotensin and sympathetic nervous systems have been suggested in the pathogenesis of hypertension, we wanted to investigate the effect of chronic renin-angiotensin blockade with losartan and enalaprilat on the sympathetic reactivity to hypotension and on the cardiac beta-adrenergic-coupled adenylyl cyclase pathway in 12-week-old Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Both treatments, exerting equipotent shifts of angiotensin-pressure responses, lowered blood pressure and attenuated cardiac hypertrophy similarly in SHR. The nitroprusside-induced hypotension was similar in both strains, but the associated increases in plasma catecholamines and heart rate were higher in SHR. In SHR treated with losartan and enalaprilat, the nitroprusside-induced hypotension was greater and associated with markedly attenuated increases in norepinephrine and heart rate. The binding affinity of cardiac beta-adrenoceptors was significantly lower, and beta2-adrenoceptor subtype was dominant in untreated SHR in contrast to WKY, in which beta1-adrenoceptor subtype was dominant. Enalaprilat treatment increased total beta-adrenoceptor density, whereas both treatments restored the binding affinity and beta1- and beta2-adrenoceptor proportions to normal in SHR. Isoproterenol-, guanylylimidodiphosphate [Gpp(NH)p]-, and forskolin-stimulated adenylyl cyclase reactivity was increased in SHR. Enalaprilat restored adenylyl cyclase reactivity to normal in SHR and reduced the sensitivity (EC50) of Gpp(NH)p-induced cAMP formation in both strains. The present study supports the possibility that functional alterations of the renin-angiotensin and sympathetic systems are involved in hypertension in SHR. The antihypertensive action of losartan and enalaprilat in SHR may be partly mediated through the normalization of sympathetic hyperreactivity and the restoration of beta-adrenergic signaling pathway sensitivity.