Multiple Sclerosis: A neurodegenerative autoimmune disease • Overview • Pathophysiology • Prevalence • Research ongoing A chronic autoimmune disorder that progressively robs sufferers of cognitive function, the ability to sense the world around them, and the capacity to walk P. Martini
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Multiple Sclerosis: A neurodegenerative autoimmune disease
Multiple Sclerosis: A neurodegenerative autoimmune disease. Overview Pathophysiology Prevalence Research ongoing. A chronic autoimmune disorder that progressively robs sufferers of cognitive function, the ability to sense the world around them, and the capacity to walk. P. Martini. - PowerPoint PPT Presentation
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• Overview• Pathophysiology• Prevalence• Research ongoing
A chronic autoimmune disorder that progressively robs sufferers of cognitive function, the ability to sense the world around them, and the capacity to walk
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MULTIPLE SCLEROSIS FEATURES• Autoimmune disease of CNS; a two stages disease: inflammation and
neurodegeneration
• 4,000,000 people affected worldwide
• Women:men 2:1
• Age of disease onset: 25-30 ys (young adulthood)
• Neurological impairments: blindness, loss of sensation, lack of coordination, incontinence, paralysis
Disease Overview: AutoImmunityPeripheral tolerance involves a populations of regulatory T cells which maintain
autoreactive T cells in a “dormant” state in the circulation in adults. The autoreactive T cells can be awoken from this state by local or environmental stimuli such as exposure
to endogenous or exogenous antigens in the circulation. In MS these cells becomes activated either because of failure of the mechanism of peripheral tolerance or due to
priming by antigens. Once activated autoreactive T cells release a cocktails of cytokines that are important for migration and homing of the cells to the target sites and for
initiation of the inflammatory process
Hartung H.P., J. Neurol. 2005 (252) P. Martini
Disease Overview: Multiple SclerosisMultiple Sclerosis (MS) is an inflammatory disease of the Central Nervous System (CNS) affecting the brain and spinal cord. Predominantly, it is a disease of the "white matter" tissue. The white matter is made up of nerve fibres which are responsible for transmitting communication signals both internally within the CNS and between the CNS and the nerves supplying rest of the body.
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Axons are transected during inflammatory demyelination
Cortical demyelination and neuronal pathology in MS
MULTIPLE SCLEROSIS: AN ELUSIVE ETIOLOGY
The causes are enigmatic:
interplay between environment and genetic factors
Environmental factors
Genes
Post genomic modifications
MS
Pathogens – molecular mimicry
Chemicals
Diet
Geography
Gene rearrangements
Somatic mutations
Retroviral
mRNA splicing
Genome allelic variations
Monozygotic twins 30%
Linkage and association studiesP. Martini
Pathophysiology
• Reasons why MS occurs is unknown
• Pathogenic mechanisms of MS remain poorly understood, thus complicating drug design and development
• Even in the earliest stages, the chronically activated proinflam-matory T lymphocytes attack myelin in brain & spinal cord, causing lesions detectable by MRI
Key Takeaways
Baranzini S.E. et al, Genome Biology 2002: 3(10) 1027.1-1027.5 P. Martini
Maturation profile of Natural Killer cells (NK cells)
Disease Overview: Multiple Sclerosis
Disease course:MS is an ongoing process of demyelination, remyelination, and eventual neuron loss
Relapses & Remissions: Most MS sufferers experience periods of acute exacerbations (flares, relapses) varying in number and severity, followed by periods of remission, where all symptoms spontaneously cease: inflammationdamage to CNS is continuous, occurring during flares AND remissions
Results: Repeated attacks on the axon, the surrounding myelin sheath eventually causes scarring or plaques that interrupt or even block nerve impulses, causing progressive cognitive/physical disability
Heterogeneity: Symptoms, severity, and course vary per person and disease seems to follow a distinct progression in each individual pt
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MS Prevalence – USEstimated that 86% of prevalent cases are diagnosed
and ~55% are treated
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• Affects 350,000+ US; • No cure; Not a fatal disease, however higher mortality rate vs. age-gender
matched population due to Suicide, autonomic nervous system failure, cardiac/ respiratory failure
• More common in people in northern latitudes, Northern European decent• MS dramatically affects a person’s quality of life vs duration of life
Est
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.S. P
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0
50000
100000
150000
200000
250000
300000
350000
400000
Male
Female
Source: Epi database
Sources: Multiple Sclerosis: Cognos Study #73. Decision Resources, Inc. October 2003; Iddb, The Changing Face of Multiple Sclerosis Therapy. Rodman & Renshaw Biotechnology Report, March 3, 2006
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Diagnosis, Clinical Forms, and Treatment
• Symptoms
• Patient Flow & Diagnosis Criteria
• MS Clinical Forms & Classifications
• Current Treatment Paradigm
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MS Symptoms Develop during acute exacerbations or as the cumulative result of multiple lesions in the CNS
Cerebrum & Cerebellum
Lesion Location
• Not all symptoms affect all MS patients• No two persons have identical complaints• No one person develops all of the symptoms
Symptoms can include: Fatigue (most common), sensory complaints, tremors, balance/coordination, depression, spasticity, bladder, bowel, vision loss, cognitive and emotional dysfunction, and sexual difficulties
CNS Lesion Location and Possible Associated Symptoms of MS:
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Patient Flow Patient Presentation
• Problems with walking/limb control• Altered sensations• Intestinal, bladder incontinence• Visual disturbances• Memory & concentration problems• Extreme fatigue• Lack of sexual energy• Depressions, anxiety, panic attacks, mood swings
Symptoms
• Depression(50-60% pts)
• Suicide risks (3-15%)
• Pts & families often require counseling
Psychologists PT/Vocational
• To treat associated physical disability
• Monitoring• Act as
“manager” for active disease
• SE’s• Disability
Nurses
PCPs
• Rarely diagnose• If MS suspected, refer to Neurologist
• No clinical, lab, or imaging tests• Misdiagnose, ‘miss it,’ or just don’t screen• Disappearing symptoms
Barriers
• Diagnose• Treat• Manage disease
Neurologists
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Diagnosing MS
McDonald Diagnosis Criteria for MS: An Improvement
McDonald Criteria (est. 2001, revised in 2005):• Introduced the following two MS diagnosis
classifications:- Definite MS and Possible MS
• Allows Neurologists to make definitive diagnosis of MS after the following events:
- CIS (clinically isolated syndrome)- With MRI findings
McDonald Criteria allows for an early and accurateMS diagnosis:
• Important for patient care – allows early treatment • Impacts clinical trials of new treatments – MRI
increasingly used as a primary end point
Standard MS Diagnosis Criteria:1. Disease in different parts of the nervous system, and 2. Signs of at least two separate flare-ups, occurring at least 30 days apart
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Source: National Multiple Sclerosis Society & NIH estimates
Clinical Forms of MSFour internationally recognized general categories
Relapsing-remitting
(RRMS): 55%
Secondary Progressive (SPMS): 35%
Primary Progressive (PPMS) 9%
Progressive Relapsing (PRMS): 1%
• Clearly defined flare-ups & remissions; inflammatory lesions developing constantly
• Early 20s & 30s; women 2:1• Initial disease activity in brain
(cognitive)• Better prognosis: supporting
equipmentavg. 20 yrs
• Majority of RRMS pts will develop SPMS(90% in 25-30 years)
• Relapse frequency decreases but disability increases• Less remyelination & more plaques, resulting in steadily progressive disability with less recovery• Could represent different, advanced stage of RRMS
• At onset, steady worsening without relapses or remissions
• Variations in rates of progression; occasional plateaus or temporary minor improvements
• Late 30s/early 40s; men as likely as women
• Initial disease activity in spinal cord (physical disability)
Degeneration of chronically demyelinated axons:Loss of trophic support. SPMS.
Relapsing MS and Progressive MSThese two classifications are critical to understanding the current & future treatment paradigms
Sources: National Multiple Sclerosis Society; http://www.multsclerosis.org/progressiverelapsingmultiplesclerosis.html
RRMS PPMSSPMS
Treatment Objective:Address the degenerative component• Slow disability progression
Treatment Objective:Address the inflammatory component• Prevent new attacks• Improve MRI outcome• Slow disability progression
Relapsing MSRRMS, worsening RRMS,
SPMS with relapses
Progressive MSSPMS without relapses, PPMS
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Relapsing MS and Progressive MSThese two classifications are critical to understanding the current & future treatment
paradigms
Sources: National Multiple Sclerosis Society; http://www.multsclerosis.org/progressiverelapsingmultiplesclerosis.html ; Sospedra et al., Annu. Rev. Immunol., 2005: (23) 683-747
Relapsing MSRRMS, worsening RRMS,
SPMS with relapses
Progressive MSSPMS without relapses, PPMS
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NEW PARADIGM FOR MS NEW PARADIGM FOR MS CLINICAL CLINICAL CLASSIFICATION OF OF
Primary-Progressive (PP):
Relatively rare, 10%. Slow but continuous worsening of disease from the onset. No distinct relapses or remission.
RRMS PRMSRelapsing-Remitting (RR):
Most common, 80%. Defined by relapses when symptoms become worse followed by partial or complete recovery periods.
SPMS=PPMS RPMSSecondary-Progressive (SP):
50% of people with RR develop SP within 10 years. Initial period of RR disease, followed by a steadily worsening disease course; occasionally minor remissions. P. Martini
Relapsing MS
CONCURRENT THERAPY
• Short-term, high-dose corticosteroid treatment
• Standard through an acute relapse
• Methylprednisolone• Prednisone
FIRST-LINE• All approved for Relapsing MS• Disease modifying• Used as monotherapy
• IFNβs• Glatiramer acetate• Monoclonal antibody
RelapsingMS
Treatment Overview
SECOND-LINE THERAPIES• First-line tx is not tolerated, non-
responders, or worsening relapsing disease• Chemotherapeutics
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Progressive MS Treatment Overview
ProgressiveMS
SECOND- & THIRD-LINE THERAPIES
• Polytherapy given to pts who continue to deteriorate despite treatment with first-line therapies
Other drugs currently used or considered for the treatment of MS
Top Unmet Needs vs. Current Product Performance
Av
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No
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Reversing neuronal damage
Prevention of disease progression
Improved therapies for Progressive forms of MS
More convenient drug delivery
- No current MS therapy addresses neuronal damage - Current therapies moderately effective in slowing disease progression
- Relatively little therapeutic effect offered for Progressive MS- Inconvenient drug delivery (injectables, IV infusions)
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Top Current Unmet Needs and Future Products
Reversing neuronal damage
Prevention of disease progression
Improved therapies for Progressive forms of MS
More convenient drug delivery
- No advances likely to be made in addressing neuronal damage- Little to no advances will be made in slowing disease
progression - Potential for improved therapies to treat Progressive MS - Mode of drug delivery likely to be significantly improved
Current tx Future txUnmet Need
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Therapeutic approaches in MS
info.sanguinebio.com
Delivery of MS drugs by injection
Timeline of IFN and GA trials
The Human Interferon
Signal transduction pathways activated by IFNs
http://www.ms-gateway.com
How IFNbeta is produced
www.interferonsource.com
Mechanism of action of IFNbeta
Glatiramer Acetate GA modifies the adaptive immune system
Interplay between Antigen Presenting Cells APC and T cellsRole of Glatiramer
Cross reactivity between Myelinic Basic Protein MBP and GA at the T cell level
Animals with EAE serve as animal models for MS.
It is NOT a single disease in a single species.
It’s INDUCED by injecting specific myelin proteins in combination with an immune-exciting agent (adjuvant).
It’s a disease of the BRAIN and SPINAL CORD.
Like MS, it’s an INFLAMMATORY DEMYELINATING AUTOIMMUNE disease.
Like MS, it takes several clinical forms, including RELAPSING-REMITTING and CHRONIC-PROGRESSIVE.
BENEFITS:•Identifying sites in the CNS more likely to develop MS lesion (plaques).•Finding out which immune cells are involved and how they interact.•Developing experimental treatments.
DISADVANTAGES:
•EAE is NOT multiple sclerosis; failure of some assumptions.