Temporal profile of lymphocyte counts and relationship with infections with fingolimod therapy

Population pharmacokinetics and pharmacodynamics of ponesimod, a selective S1P1 receptor modulator

Ponesimod (ACT-128800), a reversible, orally active, selective S1P1 receptor modulator, prevents the egress of lymphocytes from the lymph node into the systemic circulation. It is currently in clinical development for the treatment of relapsing multiple sclerosis. Modulation of circulating lymphocytes serves as biomarker of efficacy and safety, such that the quantitative characterization of the pharmacokinetic/pharmacodynamic (PK/PD) relationship guides the clinical development of the compound. The availability of a variety of doses, dosing regimens, and treatment durations permitted estimation of the pharmacokinetics characterized by an absorption lag time followed by a sequential zero/first-order absorption and two compartments with first-order elimination. The PD are modeled as an indirect-effect model with rates of appearance and disappearance of lymphocytes in blood with a circadian rhythm and a drug effect on the rate of appearance. The model suggests a circadian variation of 9% and a maximum inhibition of 86% of total lymphocyte count with high doses at steady state. It was instrumental for the selection of doses for subsequent studies that confirmed the effect plateau in total lymphocyte count at approximately 0.5 × 10(9) counts/L.

Fingolimod in relapsing multiple sclerosis: An integrated analysis of safety findings

BACKGROUND

Fingolimod 0.5mg once daily is the first approved oral therapy for relapsing multiple sclerosis (MS).

OBJECTIVE

To report integrated long-term safety data from phase 2/3 fingolimod studies.

METHODS

Descriptive safety data are reported from the FTY720 Research Evaluating Effects of Daily Oral Therapy in Multiple Sclerosis (FREEDOMS) study, a 24-month, randomized, double-blind study comparing fingolimod 0.5mg and 1.25mg with placebo, and an All Studies group (patients who received fingolimod 0.5mg (n=1640) or 1.25-0.5mg (n=1776) in phase 2/3 studies and associated extensions). Relevant post-marketing experience, up to December 2011, is included.

RESULTS

The incidence of adverse events (AEs) and serious AEs (SAEs) was similar with fingolimod and placebo in FREEDOMS. In the All Studies group, fingolimod 0.5mg was associated with transient, rarely symptomatic (0.5%), bradycardia and second-degree atrioventricular block on treatment initiation, minor blood pressure increases, frequent (9%) but generally asymptomatic liver enzyme elevations, and macular oedema (0.4%). The incidences of infections (including serious and herpes infections), malignancies, SAEs and treatment discontinuations due to AEs were similar with fingolimod 0.5mg and placebo.

CONCLUSION

The safety profile of fingolimod has been well characterized in this large combined trial population. Although infrequent SAEs can occur, there is no increased risk of infections, malignancies or serious cardiovascular events versus placebo.

Immunological mechanism of action and clinical profile of disease-modifying treatments in multiple sclerosis

Multiple sclerosis (MS) is a life-long, potentially debilitating disease of the central nervous system (CNS). MS is considered to be an immune-mediated disease, and the presence of autoreactive peripheral lymphocytes in CNS compartments is believed to be critical in the process of demyelination and tissue damage in MS. Although MS is not currently a curable disease, several disease-modifying therapies (DMTs) are now available, or are in development. These DMTs are all thought to primarily suppress autoimmune activity within the CNS. Each therapy has its own mechanism of action (MoA) and, as a consequence, each has a different efficacy and safety profile. Neurologists can now select therapies on a more individual, patient-tailored basis, with the aim of maximizing potential for long-term efficacy without interruptions in treatment. The MoA and clinical profile of MS therapies are important considerations when making that choice or when switching therapies due to suboptimal disease response. This article therefore reviews the known and putative immunological MoAs alongside a summary of the clinical profile of therapies approved for relapsing forms of MS, and those in late-stage development, based on published data from pivotal randomized, controlled trials.

Treatment options for patients with multiple sclerosis who have a suboptimal response to interferon-β therapy

BACKGROUND AND PURPOSE

Although the first-line disease-modifying therapies (DMTs) interferon beta and glatiramer acetate have a favourable benefit-to-risk profile, they are only partially effective for treating relapsing-remitting multiple sclerosis (RRMS). The optimization of treatment in patients who do not show a maximum response to first-line therapy is critical for achieving the best long-term outcomes. Treatment strategies for patients with a suboptimal response include switching to another first-line DMT or a second-line DMT. Natalizumab and fingolimod are approved for RRMS with high disease activity in the European Union and Canada.

METHODS

A comprehensive literature search for articles published between 1990 and April 2012 was undertaken.

RESULTS

This review discusses key clinical and safety data for fingolimod and natalizumab, particularly in the patient subgroups for whom these treatments are approved. Benefit-to-risk profiles, including first-dose cardiovascular effects associated with fingolimod and the risk of progressive multifocal encephalopathy with natalizumab, are discussed.

CONCLUSION

A descriptive comparison of fingolimod and natalizumab is provided in the context of the decision-making process of how and when to switch patients who have a suboptimal response to first-line therapy.