Fingolimod, a sphingosine-1-phosphate receptor (S1PR) modulator, was the first oral disease-modifying therapy approved for relapsing forms of multiple sclerosis; it reduces autoreactive lymphocytes' egress from lymphoid tissues by down-regulating S1PRs. Sphingosine-1-phosphate signaling is implicated in a range of physiologic functions, and S1PRs are expressed differentially in various tissues, including the cardiovascular system. Modulation of S1PRs on cardiac cells provides an explanation for the transient effects of fingolimod on heart rate and atrioventricular conduction at initiation of fingolimod therapy, and for the mild but more persistent effects on blood pressure observed in some patients on long-term treatment. This review describes the nontherapeutic actions of fingolimod in the context of sphingosine-1-phosphate signaling in the cardiovascular system, as well as providing a summary of the associated clinical implications useful to physicians considering initiation of fingolimod therapy in patients. A transient reduction in heart rate (mean decrease of 8 beats per minute) and, less commonly, a temporary delay in atrioventricular conduction observed in some patients when initiating fingolimod therapy are both due to activation of S1PR subtype 1 on cardiac myocytes. These effects are a reflection of fingolimod first acting as a full S1PR agonist and thereafter functioning as an S1PR antagonist after down-regulation of S1PR subtype 1 at the cell surface. For most individuals, first-dose effects of fingolimod are asymptomatic, but all patients need to be monitored for at least 6 hours after the first dose, in accordance with the label recommendations.

Abstract. The efficacy-safety and pharmacokinetics of the six-dose regimen of artemether-lumefantrine (Coartem/ Riamet; Novartis Pharma AG, Basel, Switzerland) were assessed in a randomized trial in 219 patients (Ն 12 years old) with acute, uncomplicated Plasmodium falciparum malaria in Thailand. One hundred and sixty-four patients received artemether-lumefantrine and 55 received the standard treatment combination of mefloquine-artesunate. Both drugs induced rapid clearance of parasites and malaria symptoms. The 28-day cure rates were 95.5% (90% confidence interval [CI] ϭ 91.7, 97.9%) for artemether-lumefantrine and 100% (90% CI ϭ 94.5, 100%) for mefloquine-artesunate. This high-dose regimen of artemether-lumefantrine was very well tolerated, with very good compliance. The most frequent adverse events were headache, dizziness, nausea, abdominal pain, dyspepsia, vomiting, and skin rash. Overall, only 2% of patients in both groups showed QTc prolongations but without any cardiac complication, and no differences were seen between patients with and without measurable baseline plasma levels of quinine or mefloquine. Plasma levels of artemether, dihydroartemisinin, and lumefantrine were consistent with historical data for the same dose regimen, and were higher, particularly for lumefantrine, than those previously observed with the four-dose regimen, explaining the greater efficacy of the six-dose regimen in a drug-resistant setting. These results confirm the excellent safety and efficacy of the six-dose regimen of artemether-lumefantrine in the treatment of multidrug-resistant P. falciparum malaria.

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Hyponatremia, an electrolyte disturbance usually without clinical significance, may sometimes lead to serious complications when overlooked or not treated appropriately. One cause of hyponatremia, the syndrome of inappropriate antidiuretic hormone (SIADH) secretion, has been associated with some drugs, including carbamazepine (CBZ). Because of its antidiuretic effects, CBZ has been used successfully to treat diabetes insipidus centralis. Possible mechanisms for the antidiuretic effects of CBZ have been proposed. Altered sensitivity to serum osmolality by the hypothalamic osmoreceptors appears likely, but an increased sensitivity of the renal tubules to circulating ADH cannot be excluded. CBZ has led to hyponatremia in patients with epilepsy, neuralgia, mental retardation, and psychiatric disorders with a frequency varying from 4.8 to 40%. Oxcarbazepine (OCBZ), which is structurally related to CBZ, has shown similar hyponatremic effects, but whether hyponatremia occurs more often than with CBZ is not yet clear. Experience with OCBZ is still limited, and there is no definite explanation for a possible difference in antidiuretic potency. Most patients with CBZ/OCBZ-induced hyponatremia are asymptomatic. In rare cases, water intoxication has been reported, necessitating treatment discontinuation.

BackgroundThe fixed dose combination of artemether-lumefantrine (AL) is the most widely used treatment for uncomplicated Plasmodium falciparum malaria. Relatively lower cure rates and lumefantrine levels have been reported in young children and in pregnant women during their second and third trimester. The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties of lumefantrine and the pharmacokinetic properties of its metabolite, desbutyl-lumefantrine, in order to inform optimal dosing regimens in all patient populations.Methods and findingsA search in PubMed, Embase, ClinicalTrials.gov, Google Scholar, conference proceedings, and the WorldWide Antimalarial Resistance Network (WWARN) pharmacology database identified 31 relevant clinical studies published between 1 January 1990 and 31 December 2012, with 4,546 patients in whom lumefantrine concentrations were measured. Under the auspices of WWARN, relevant individual concentration-time data, clinical covariates, and outcome data from 4,122 patients were made available and pooled for the meta-analysis. The developed lumefantrine population pharmacokinetic model was used for dose optimisation through in silico simulations. Venous plasma lumefantrine concentrations 7 days after starting standard AL treatment were 24.2% and 13.4% lower in children weighing <15 kg and 15–25 kg, respectively, and 20.2% lower in pregnant women compared with non-pregnant adults. Lumefantrine exposure decreased with increasing pre-treatment parasitaemia, and the dose limitation on absorption of lumefantrine was substantial. Simulations using the lumefantrine pharmacokinetic model suggest that, in young children and pregnant women beyond the first trimester, lengthening the dose regimen (twice daily for 5 days) and, to a lesser extent, intensifying the frequency of dosing (3 times daily for 3 days) would be more efficacious than using higher individual doses in the current standard treatment regimen (twice daily for 3 days). The model was developed using venous plasma data from patients receiving intact tablets with fat, and evaluations of alternative dosing regimens were consequently only representative for venous plasma after administration of intact tablets with fat. The absence of artemether-dihydroartemisinin data limited the prediction of parasite killing rates and recrudescent infections. Thus, the suggested optimised dosing schedule was based on the pharmacokinetic endpoint of lumefantrine plasma exposure at day 7.ConclusionsOur findings suggest that revised AL dosing regimens for young children and pregnant women would improve drug exposure but would require longer or more complex schedules. These dosing regimens should be evaluated in prospective clinical studies to determine whether they would improve cure rates, demonstrate adequate safety, and thereby prolong the useful therapeutic life of this valuable antimalarial treatment.

Since the approval of fingolimod, several selective sphingosine-1-phosphate receptor modulators have entered clinical development for multiple sclerosis. However, side effects can occur with sphingosine-1-phosphate receptor modulators. By considering short-term data across the drug class and longer term fingolimod data, we aim to highlight the potential of sphingosine-1-phosphate receptor modulators in multiple sclerosis, while offering reassurance that their benefit–risk profiles are suitable for long-term therapy. Short-term fingolimod studies demonstrated the efficacy of this drug class, showed that cardiac events upon first-dose administration are transient and manageable, and showed that serious adverse events are rare. Early-phase studies of selective sphingosine-1-phosphate receptor modulators also show efficacy with a similar or improved safety profile, and treatment initiation effects were reduced with dose titration. Longer term fingolimod studies demonstrated sustained efficacy and raised no new safety concerns, with no increases in macular edema, infection, or malignancy rates. Switch studies identified no safety concerns and greater patient satisfaction and persistence with fingolimod when switching from injectable therapies with no washout period. Better outcomes were seen with short than with long washouts when switching from natalizumab. The specific immunomodulatory effects of sphingosine-1-phosphate receptor modulators are consistent with the low observed rates of long-term, drug-related adverse effects with fingolimod. Short-term data for selective sphingosine-1-phosphate receptor modulators support their potential effectiveness in multiple sclerosis, and improved side-effect profiles may widen patient access to this drug class. The long-term safety, tolerability, and persistence profiles of fingolimod should reassure clinicians that sphingosine-1-phosphate receptor modulators are likely to be suitable for the long-term treatment of multiple sclerosis.Electronic supplementary materialThe online version of this article (doi:10.1007/s40265-017-0814-1) contains supplementary material, which is available to authorized users.

Artemether-lumefantrine (A-L), a new fixed-dose oral antimalarial drug, combines the fast onset of action of artemether (an artemisinin derivative) in terms of parasite clearance with the high cure rate of lumefantrine in the treatment of acute uncomplicated Plasmodium falciparum malaria. The extensive clinical trial database of A-L has allowed a comprehensive evaluation of its tolerability and safety in a total of 1869 patients (including 243 children aged 5-12 years and 368 children aged < 5 years). The most commonly reported and possibly related adverse effects following A-L therapy involved the gastro-intestinal (abdominal pain, anorexia, nausea, vomiting, diarrhoea) and central nervous (headache, dizziness) systems. Pruritus and rash were reported by < 2% of patients. More than 90% of the reported adverse events, many of which overlapped considerably with the clinical symptomatology or evolution of acute malaria, were rated mild to moderate in intensity. Compared to A-L, significantly higher incidences of vomiting and pruritus were observed with chloroquine, dizziness, nausea and vomiting with mefloquine, somnolence with pyrimethamine + sulfadoxine, and vomiting and dizziness with quinine. There were no serious or persistent neurological side-effects related to A-L administration. A-L did not lead to any clinically relevant alterations of the laboratory parameters. Serial electrocardiographic data were available for 713 patients. The frequency of QT interval prolongations was similar to or lower than that observed with chloroquine, mefloquine, or artesunate + mefloquine; these changes were considerably less frequent than with quinine or halofantrine. All patients with QT prolongation remained asymptomatic and no adverse clinical cardiac events were reported. Artemether-lumefantrine can thus be expected to show, both in children and in adults, a favourable safety profile for the treatment of acute, uncomplicated, P. falciparum malaria; it could as well be a reserve treatment option for travellers to endemic countries.

The analgesic efficacy of single oral doses of drinkable diclofenac dispersible 50 mg was compared with that of ibuprofen 400 mg and placebo in a randomized, double-blind, parallel-group trial in 257 adult patients (245 valid for efficacy) with severe postoperative pain after extraction of an impacted lower third molar. In this study, pain intensity (on a 100-mm visual analog scale) and pain relief from baseline (using a five-point verbal rating scale) were assessed serially during an observation period of 6 hours. Intake of rescue analgesic was permitted in case of insufficient therapeutic effect; however at least 1 hour should have elapsed after test drug consumption. On the main efficacy variable, namely, reduction in the pain intensity score, both diclofenac dispersible (n = 83) and ibuprofen (n = 80) were statistically significantly (P < .01) superior to placebo (n = 82) starting at 20 and 40 minutes, respectively, after drug intake. The active medications were also significantly (P < .01) better than placebo for the secondary efficacy parameters viz. summed pain relief scores over 6 hours (TOTPAR-6); frequency of remedication with a rescue analgesic in the three treatment groups (diclofenac, 24%; ibuprofen, 28%; placebo, 65%); mean time to remedication; and global evaluation. All the treatments were well tolerated. Thus assay sensitivity of this trial (ibuprofen significantly better than placebo) has been demonstrated; in addition, diclofenac as a dispersible formulation has been shown to be an effective analgesic for the treatment of post-surgical dental pain.