Disclosed is a composition of matter of the formula (X<1>)a-(F<1>)d-(X<2>)b-(F<2>)e-(X<3>)c and multimers thereof, in which F<1> and F<2> are half-life extending moieties, and d and e are each independently 0 or 1, provided that at least one of d and e is 1; X<1>, X<2>, and X<3> are each independently -(L)f-P-(L)g-, and f and g are each independently 0 or 1; P is a
toxin peptide of no more than about 80
amino acid residues in length, comprising at least two intrapeptide disulfide bonds; L is an optional
linker; and a, b, and c are each independently 0 or 1, provided that at least one of a, b and c is 1. Linkage to the half-life extending
moiety or moieties increases the
in vivo half-life of the
toxin peptide, which otherwise would be quickly degraded. A pharmaceutical composition comprises the composition and a pharmaceutically acceptable carrier. Also disclosed are
a DNA encoding the inventive composition of matter, an
expression vector comprising the
DNA, and a host
cell comprising the
expression vector. Methods of treating an autoimmune disorder, such as, but not limited to,
multiple sclerosis, type 1 diabetes,
psoriasis,
inflammatory bowel disease, contact-mediated dermatitis,
rheumatoid arthritis, psoriatic
arthritis,
asthma,
allergy, restinosis, systemic sclerosis,
fibrosis, scleroderma,
glomerulonephritis, Sjogren syndrome, inflammatory
bone resorption,
transplant rejection, graft-versus-
host disease, and lupus and of preventing or mitigating a relapse of a symptom of
multiple sclerosis are also disclosed.