Therapeutic Revolution in Rheumatoid Arthritis
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Transcript Therapeutic Revolution in Rheumatoid Arthritis
Therapeutic Revolution in
Rheumatoid Arthritis
Brian J. Keroack, MD
Rheumatology Associates
Portland, Maine
Rheumatoid Arthritis
Morning stiffness>1
hour
Usually symmetric
Parameters of
systemic inflammation
>6 weeks duration
70% +RF
Rheumatoid Arthritis
Accepted Prevalence: 11.5% (classic seropositive)
200,000 new cases
annually
19.9 billion/year spent on
RA. 9.5 billion
dollars/million patients.
This exceeds cost/patient
in diabetes and
cardiovascular disease.
Rheumatoid Arthritis
affects Survival:
Impact of RA
Premature mortality
Increased morbidity
Significant impact on quality of life
– Pain with associated functional disability
– Fatigue
73% of patients
42% with severe fatigue
– Depression
Economic impact
– Work dysfunction
– Earnings loss of approximately 50%
Clinically Detectable Damage Occurs Early
in RA
MRI-detectable erosions are present within
4 months of symptom onset1
Most patients (up to 93%) with RA of < 2
years’ duration show radiographic damage2
Disease progression is more rapid during
the first year than during the second and
third years3
Cartilage in RA: Target or
Bystander?
Early:
–
–
–
–
Cytokines (IL-1, TNF-a ): Macrophages
Catabolic Effects on Chondrocytes
Proteoglycan Depletion
Weakens ability to rebound from a load
Next:
– Induction of Metalloproteinases—Stromolysin,
Collagenase
Last:
– Phagocytosis of Cartilage by Pannus
TNF-a is a pivotal cytokine
in the pathogenesis of RA
Mediates pathologic
inflammation
Mediates joint destruction
Mediates systemic,
extra-articular symptoms
of inflammation
Regulates levels of
adhesion molecules
responsible for leukocyte
migration
Parameters of Inflammation
Approach to the Treatment of
RA
Try to figure out ‘what type’ of Rheumatoid
Arthritis the patient has
This is not a uniform disease
– Young, Sero-positive patient vs. Older Sero-
negative patient.
– Abrupt vs gradual onset
– Response to 10-15 mg prednisone (‘Lourdes’
response)
Mild DMARDS vs Immunosuprssives
Approach to the Treatment of RA: Early
Immunosupression
Antiproliferative agents
– More aggressive doses of methotrexate
– Leflunomide
Biologics
– Infliximab/ Etanercept/Humira (TNF-a)
– Kineret (IL-1ra)
– Orencia (abatacept)
Rituxan (B-cell depletion)
– MRA (IL-6 receptor)
– Small Modular Immunopharmaceutical (SIMP)
Combination therapy—sooner than ever before
Weinblatt Study
Methotrexate
Multiple Trials Support Use
DMARD of Choice (but there are challengers)
Long Term Efficacy/Compliance
Radiographic Data
Relatively Rapid Onset of Action (4-8 weeks)
Dosage 7.5-25mg/week (above 20 mg inject)
I still try Methotrexate in Most RA patients before
moving on to Newer DMARDS—but I move
faster to Biologics in partial responders (2-3
months) —patience is NOT a virtue here.
I would never give you a drug worse than your
disease
TNF Inhibition: Etanercept
Etanercept
Activated
macrophage
Target
cell
Signal
TNF
Etanercept
Patients With No New Erosions
at 1 Year
All
patients
Patients with
baseline
erosions
Patients with no
baseline erosions
Finck B. Arthritis Rheum. 1999.
Etanercept
25 mg
Methotrexate
75%
(154/206)
57%
(123/217)
P < 0.001
72%
52%
P < 0.001
(130/181)
(98/188)
96%
86%
(24/25)
(25/29)
P = 0.159
Antibody Neutralization of TNFa
Infliximab in Active RA Despite MTX
ATTRACT
Improvement in Swollen Joints
MTX Control
3 mg/kg q 8 wks
10 mg/kg q 8 wks
MTX Control
3 mg/kg q 4 wks
10 mg/kg q 4 wks
ATTRACT
Infliximab in Active RA Despite MTX
Improvement in Tender Joints
MTX Control
3 mg/kg q 8 wks
10 mg/kg q 8 wks
MTX Control
3 mg/kg q 4 wks
10 mg/kg q 4 wks
ATTRACT
Infliximab in Active RA Despite MTX
Median C-reactive Protein (mg/dL)
PREMIER
2-Year Results of Selected
Clinical Responses
Percentage of Patients
70
HUMIRA + MTX
(n=268)
HUMIRA
(n=274)
60
*
*
39
36
*
34
33
30 30
30
21
20
55
53
50
40
*
MTX
(n=257) *
19 19
29
19 19
15
10
0
TJC=0
SJC=0
HAQ=0
*P<0.05 for HUMIRA + MTX vs MTX alone and HUMIRA alone
†Normal CRP was defined as ≤0.5 mg/dL
Emery P, et al. Presented at: EULAR; June 8-11, 2005; Vienna, Austria.
Data on file, Abbott Laboratories.
Morning Normal CRP†
Stiffness=0
So What is the Catch?
Cost = $17,000-25,000/year
Injections or infusions
Profound immunosupression
– Careful who you put on the drug (Diabetes,
COPD, Renal failure, etc)
– When patients present with infection, they have
more subtle complaints—fewer ‘systemic’
symptoms occur
– Low threshold for antibiotics as most serious
infections are ‘typical’
– Can you educate the patient?
The Other Biologics
Orencia: Approved by FDA 2/2006—Role
unclear—does work in TNF failures
Rituxan: 2 doses can produce a protracted
period of remission in refractory RA—
Infusion reactions (1-2%)
Orencia—CTLA4-Ig
Rituxan
Bridge to the 21st Century
Early aggressive therapy especially in young seropositive
patients—DMARDS within 3 months of diagnosis. Best
chance for remission
Methotrexate first—But in partial responders rapidly move
to TNF-a blockers. The data suggest the they should be
ADDED to Methotrexate.
Biologics to induce early remissions for those with
erosions at diagnosis.
Try more than one TNF-a blocker (70% respond to a
switch)
Orencia/Rituxan in TNF-a Failures
?Low dose prednisone (5-10 mg) combined with
osteoporosis protection—Many need it for symptoms
NSAIDS/COX-2 as bridge therapy in mild Rheumatoid
Arthritis (essentially worthless)
Future?
MRA ?—IL-6 receptor antibody (+/- data to date and
multiple problems—LFT’s, GI bleeding?) probably not a
‘player’
SIMP’s: these are single chain polypeptides with greater
tissue penetration—high affinity --??greater efficacy
We are in the ‘infancy’ of immune ‘manipulation’