Effect of fingolimod (FTY720) on cerebral blood flow, platelet function and macular thickness in healthy volunteers

Knowledge and awareness of clinical trials among trial participants in India: A multicentric questionnaire-based cross-sectional study

PURPOSE

The knowledge and attitude of participants toward clinical trials (CTs) are a key determinant in successful recruitment and retention. This study aimed to evaluate knowledge and awareness-attitude among the recruited CT participants about CTs.

METHODS

This was a cross-sectional face-to-face survey comprising CT participants involved in the past or currently a part of a CT during this study within the Indian Ophthalmology Clinical Trial Network (IOCTN). A previously validated questionnaire was used, and data regarding demographics, knowledge, and awareness-attitude about CTs were collected. The total awareness-attitude score was used to determine the knowledge and awareness of the participants.

RESULTS

A total of 121 subjects had participated in the study who were part of ongoing trials, of which only five participants had prior experience of CTs. The majority (90%) had knowledge about CTs, whereas only 7% had confirmed signing consent forms. The total awareness-attitude score significantly varied across locations (27% for the southern zone, 53% for the central zone, and 52% for the western zone), and this was negatively associated with education. The most negative attitude (38.6%) was observed regarding adequate information sharing among participants, whereas non-disruption of their routine family life (60.7%) and financial stability (67.6%) were the top most positive attitudes revealed during their participation. The participants' pre- and post-participation attitude toward CTs revealed a positive attitude.

CONCLUSION

The factors influencing a participant's knowledge and attitudes toward CTs were revealed in the study. Furthermore, the need for awareness regarding benefits of CTs to the public, participant's rights, and their voluntary power were the major highlights.

Platelet-Derived S1P and Its Relevance for the Communication with Immune Cells in Multiple Human Diseases

Sphingosine-1-phosphate (S1P) is a versatile signaling lipid involved in the regulation of numerous cellular processes. S1P regulates cellular proliferation, migration, and apoptosis as well as the function of immune cells. S1P is generated from sphingosine (Sph), which derives from the ceramide metabolism. In particular, high concentrations of S1P are present in the blood. This originates mainly from erythrocytes, endothelial cells (ECs), and platelets. While erythrocytes function as a storage pool for circulating S1P, platelets can rapidly generate S1P de novo, store it in large quantities, and release it when the platelet is activated. Platelets can thus provide S1P in a short time when needed or in the case of an injury with subsequent platelet activation and thereby regulate local cellular responses. In addition, platelet-dependently generated and released S1P may also influence long-term immune cell functions in various disease processes, such as inflammation-driven vascular diseases. In this review, the metabolism and release of platelet S1P are presented, and the autocrine versus paracrine functions of platelet-derived S1P and its relevance in various disease processes are discussed. New pharmacological approaches that target the auto- or paracrine effects of S1P may be therapeutically helpful in the future for pathological processes involving S1P.

Assessment of Macular Function by Multifocal Electroretinogram in Patients with Multiple Sclerosis Treated with Fingolimod

Introduction

This study aimed to evaluate whether treatment with fingolimod (FTY) may induce functional changes on the macular pre-ganglionic retinal elements in patients affected by relapsing–remitting multiple sclerosis (RR-MS) without optic neuritis (ON).

Methods

This case–control observational and retrospective study assessed multifocal electroretinogram (mfERG) responses from 35 healthy controls (mean age 43.58 ± 5.76 years), 41 patients with RR-MS without ON (mean age 40.64 ± 4.83 years, MS-noFTY group), and from 21 patients with RR-MS without ON (mean age 42.38 ± 12.34 years) and treated with fingolimod (Gilenya®, Novartis Europharm, 0.5 mg/day) (MS-FTY group). MfERG N1 and P1 implicit times (ITs), and N1–P1 response amplitude densities (RADs) were measured from concentric rings (R) with increasing foveal eccentricity: 0–5° (R1), 5–10° (R2), 10–15° (R3), 15–20° (R4), 20–25° (R5). We considered R1 and R2 as “central macular areas” and R3, R4 and R5 as “more eccentric retinal areas”. In the MS-FTY group, mfERG recordings were performed between 6 and 12 months (mean 7.2 ± 1.5 months) from the start of FTY.

Results

In the MS-FTY group, the mean values of mfERG N1 and P1 ITs and RADs detected in both central macular areas (R1 and R2) and in more eccentric retinal areas (R3, R4 and R5) were not significantly different (p > 0.01) with respect to those of control and MS-noFTY groups.

Conclusions

Our mfERG results suggest that the chronic use of FTY does not induce a dysfunction of pre-ganglionic retinal elements located in the 0–25° of central retina. Since FTY does not cause any retinal functional abnormality, we suggest that FTY treatment could not produce any toxic effect on pre-ganglionic retinal elements even in the absence of macular oedema.

Macular oedema and changes in macular thickness in multiple sclerosis patients treated with fingolimod

Macular oedema is a known side effect to fingolimod, but changes in specific areas of the retina are only sparsely described. Our aim was to investigate the prevalence of macular oedema and characterize macular changes after initiation of fingolimod based on routine ophthalmological examinations in all consecutive patients treated at our hospital. We evaluated macular thickness change from baseline to 3-4 months after initiation of treatment. Central retinal thickness, total macular volume, total macular thickness, average thickness and inner-/outer macular thickness were automatically measured using optical coherence tomography (OCT). A total of 190 eyes completed the study, and none of those developed visible macular oedema. All macular areas showed a small, but statistically significant increase in thickness. Total macular volume increased by a mean of 0.05 mm³ (P = <.001). Mean best-corrected visual acuity only changed by .03 (P = .074). We observed a minimal change in macular thickness and no clinically relevant affection on visual acuity after 3-4 months of fingolimod treatment. Thus, our results do not underpin the need for routine screening for macular oedema in asymptomatic MS patients without diabetes or uveitis receiving 0.5 mg fingolimod daily.

FTY720 attenuates iron deposition and glial responses in improving delayed lesion and long-term outcomes of collagenase-induced intracerebral hemorrhage

Most intracerebral hemorrhage (ICH) survivors have poor long-term outcomes, such as cognitive deficits and depression. Delayed lesions of ICH include neuron loss and white matter injury and the pathology of the lesions involves iron deposition and glial responses, which contribute to depressive-like behavior and cognitive impairment in animals. This study aimed to investigate the effects of FTY720 (0.3 mg/kg/day for 4 weeks) on iron deposition, glial responses, histological abnormalities and behavioral dysfunction in mice with ICH. The primary adverse long-term outcomes in our study of ICH mice were depressive-like behavior and impaired recognition memory. We found that FTY720 safely ameliorated depressive-like behavior and impaired recognition without affecting recovery of grip function and locomotor activity 28 days post-ICH. Moreover, we measured neuron loss, white matter lesions, lesion volume and iron deposition at day 28, which were attenuated in the FTY720-treated group compared to the ICH-control group, without changing initial hematoma volume on day 1 post-ICH. Long-term elevation of glial responses, including microglia activity and astrogliosis with tumor necrosis factor alpha (TNFα) expression was demonstrated by Western blot and immunofluorescence staining, which we found was attenuated by FTY720 treatment. Hence, FTY720 could become a novel therapeutic agent for improving long-term outcomes after ICH.

Consent for participating in clinical trials - Is it really informed?

The article explores the challenges of ensuring voluntary and informed consent which is obtained from potential research subjects in the north-eastern part of Romania. This study is one of the first empirical papers of this nature in Romania. The study used a quantitative survey design using the adapted Quality of Informed Consent (QuIC) questionnaire. The target population consisted of 100 adult persons who voluntarily enrolled in clinical trials. The informed consent form must contain details regarding the potential risks and benefits, the aim of the clinical trial, study design, confidentiality, insurance and contact details in case of additional questions. Our study confirmed that although all required information was included in the ICF, few clinical trial participants truly understood it. We also found that the most important predictive factor for a good subjective and objective understanding of the clinical trial was the level of education. Our study suggests that researchers should consider putting more effort in order to help clinical trials participants achieve a better understanding of the informed consent. In this way they will ensure that participants' decision-making is meaningful and that their interests are protected.

Immune thrombocytopenic purpura associated with fingolimod

Fingolimod is an oral sphingosine-1-phosphate receptor modulator which causes lymphocyte sequestration in lymph nodes and is approved for relapsing multiple sclerosis. The Therapeutic Goods Administration of Australia is aware of only one case where fingolimod preceded immune thrombocytopenic purpura (ITP) by 5 weeks. Here we report three such cases.None were on any medications known to cause ITP and routine investigations were unremarkable. All cases were treated with immunosuppression. Case 1 successfully weaned prednisolone after fingolimod cessation whereas case 2 weaned slowly while continuing fingolimod therapy. Case 3 had more refractory ITP and re-exposure to fingolimod worsened thrombocytopenia.There was a temporal association between fingolimod exposure and ITP however dose-effect association and pathogenesis remain less clear.In conclusion, our cases highlight that clinicians should be aware of the possible association between ITP and fingolimod.

Effect of Fingolimod on Platelet Count Among Multiple Sclerosis Patients

Background:

While many studies have previously focused on fingolimod's effect on immune cells, the effect it has on circulating and local central nervous system platelets (Plts) has not yet been investigated. This study will elucidate what effects fingolimod treatment has on multiple sclerosis (MS) patients’ plasma Plt levels. In addition, it will propose possible reasoning for these effects and suggest further investigation into this topic.

Methods:

This quasi-experimental study used patients from the Isfahan Multiple Sclerosis Society to produce a subject pool of 80 patients, including 14 patients who ceased fingolimod use due to complications. The patients had their blood analyzed to determine Plt levels both 1-month prior to fingolimod treatment and 1-month after fingolimod treatment had been started.

Results:

The mean level of Plts before initiation of fingolimod therapy (Plt1) among these MS patients was 256.53 ± 66.26. After 1-month of fingolimod treatment, the Plt level yielded an average of 229.96 ± 49.67 (Plt2). This number is significantly lower than the average Plt count before treatment (P < 0.01).

Conclusions:

MS patients taking oral fingolimod treatment may be at risk for side-effects caused by low Plt levels. This may not be a factor for patients with higher or normal Plt levels. However, a patient with naturally low Plt levels may experience a drop below the normal level and be at risk for excessive bleeding. In addition to these possible harmful side-effects, the decreased Plt population may pose positive effects for MS patients.