Psoriasis is a common skin disease affecting an estimated 2.6% of the US population. It is
a chronic, recurrent condition for which there is no cure, but there are ways to control it.
Psoriasis is characterized by epidermal hyperplasia (abnormal increase in the number of
normal cells of the outer layer of the skin). Tetrathiomolybdate (TM), a copper chelator (a
drug that removes copper from the bloodstream) was first created to treat Wilson's disease,
a disorder caused by too much copper in the blood. Studies in animals have since shown that
TM may also prevent the formation of new blood vessels and may also block the key components
of inflammation (swelling, redness, and pain) caused by psoriasis. TM is not approved by
the FDA for any use yet. It is an investigational drug used for clinical research. We
propose to test whether a new treatment with TM can in fact improve or stabilize psoriasis.
The purpose of this study is to evaluate the safety and efficacy of Tetrathiomolybdate in
psoriasis therapy. Psoriasis is a common skin disease affecting an estimated 2.6% of the US
population. It is a chronic, recurrent condition for which there is no cure but ways to
control it. Psoriasis is characterized by epidermal hyperplasia, increased dermal
angiogenesis, and infiltration of activated lymphocytes. Beginning with the observation
that cyclosporin A, whose primary action is to inhibit lymphokine release and proliferation
of T cells, was effective in the treatment of psoriasis, the last two decades saw a major
paradigm shift in the pathogenesis of psoriasis, from a view of psoriasis as a disease of
epidermal origin to a view of it as an epidermal response to immunological injury. In fully
activated T cells in psoriatic skin, the T1/T2 cytokine balance is shifted in favor of T1
expression, with production of IL-2 and IFN-γ. Activated T1 lymphocytes also produce TNF-α.
This is a pivotal cytokine that regulates an array of proinflammatory mediators. Recently,
anti-TNF-α therapy using a chimeric anti-TNF-α monoclonal antibody (infliximab) and a
TNF-receptor-immunoglobulin fusion protein (etanercept) have shown to be highly effective in
patients with severe psoriasis. Efforts to treat psoriasis by inhibiting neovascularization
of psoriatic plaques have also been shown to be effective. A randomized phase I/II clinical
trial using Neovastat, a naturally occurring inhibitor of angiogenesis, resulted in
dose-dependent improvement in the Psoriasis Area and Severity Index (PASI) score, thus
providing further evidence that altered angiogenesis is an integral part of psoriasis
pathophysiology. Since TM has proven antiangiogenic and anti-TNF-α activities, we are very
encouraged that TM therapy will be beneficial in psoriasis.
- 18 + years of age
- Psoriasis vulgaris involving greater than 5% total body surface area
- No disease states or physical conditions which would impair evaluation of the test
- Willing and able to take test medications as directed in the protocol, make
evaluation visits and follow protocol restrictions
- Failed systemic therapy for psoriasis (e.g., PUVA, retinoids, systemic steroids,
- Signed, written, witnessed informed consent form
- You must live within a reasonable driving distance of Ann Arbor, Michigan, and/or be
able to attend all of the scheduled appointments during the study.
- Use of any topical psoriasis treatment within weeks prior to the start of the study
- Use of any systemic medication within 4 weeks prior to the start of the study
- Involvement in an investigational study within the previous 4 weeks
- Inability to give informed consent
- History of drug dependency or alcoholism
- Severe infection within 4 weeks prior to study entry or the presence of chronic
- Significant psychiatric disorder
- Screening laboratory values which exceed the following limits:
- Hematology - WBC <3,500 cells/mm3, Hb <10.5g/dl, platelets <100,000 cells/mm3;
- Renal function test - creatinine >1.5 mg/dl;
- Liver function tests - AST, alkaline phosphatase or total bilirubin more than
twice the upper limits of normal, and a prothrombin time above the normal range.
- Pregnancy or breast feeding a baby. Sexually active women of reproductive age must
use an acceptable form of birth control.