Treatment with the phosphodiesterase type-4 inhibitor rolipram fails to inhibit blood--brain barrier disruption in multiple sclerosis.
Rolipram, a prototypic phosphodiesterase-4 inhibitor, is highly effective in suppressing Th1 autoimmunity in multiple animal models, including experimental autoimmune encephalomyelitis. In addition, rolipram has been extensively studied as a potential neuroprotective agent. Based on its anti-inflammatory activity, we tested the efficacy of rolipram in suppressing inflammatory disease activity in multiple sclerosis in a proof-of-principle phase I/II open-label clinical trial. Enrolled MS patients were evaluated by monthly MRI and clinical examinations during 3 months (four MRIs) of pretreatment baseline and 8 months of rolipram therapy. The primary outcome was a change in contrast-enhanced lesions between baseline and the last 4 months of rolipram therapy. Previously defined biomarkers of rolipram-mediated immunomodulation were evaluated during the study. The trial was stopped prematurely because the drug was poorly tolerated and because of safety concerns: we observed an increase, rather than decrease, in the brain inflammatory activity measured by contrast-enhanced lesions on brain MRI. At the administered doses rolipram was active in vivo as documented by immunological assays. We conclude that the reasons underlying the discrepancy between the therapeutic efficacy of rolipram in experimental autoimmune encephalomyelitis versus multiple sclerosis are at present not clear.
Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
Bibiana
B
Bielekova
Nancy
N
Richert
Thomas
T
Howard
Amy N
AN
Packer
Gregg
G
Blevins
Joan
J
Ohayon
Henry F
HF
McFarland
Claus-Steffen
CS
Stürzebecher
Roland
R
Martin
D015415:Biomarkers / Q000378:metabolism; D001812:Blood-Brain Barrier / Q000187:drug effects* / Q000473:pathology; D049109:Cell Proliferation / Q000187:drug effects; D003287:Contrast Media; D006801:Humans; D016130:Immunophenotyping; D007249:Inflammation / Q000175:diagnosis / Q000188:drug therapy / Q000473:pathology; D008279:Magnetic Resonance Imaging; D009103:Multiple Sclerosis / Q000175:diagnosis / Q000188:drug therapy* / Q000276:immunology / Q000378:metabolism*; D058988:Phosphodiesterase 4 Inhibitors; D010726:Phosphodiesterase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D020889:Rolipram / Q000009:adverse effects / Q000627:therapeutic use*; D013601:T-Lymphocytes / Q000473:pathology; D013997:Time Factors; D017211:Treatment Failure
D015415:Biomarkers; D003287:Contrast Media; D058988:Phosphodiesterase 4 Inhibitors; D010726:Phosphodiesterase Inhibitors; D020889:Rolipram