Otrexup (Methotrexate Injection) Launched for Treatment of Psoriasis in Adults
First subcutaneous methotrexate product for once-weekly administration
Otrexup (methotrexate injection, Antares Pharma/Leo Pharma) is now available to dermatologists for use in adults who need symptomatic control of severe recalcitrant, disabling psoriasis that is not adequately responsive to other forms of therapy.
The treatment is also indicated for adults with severe, active rheumatoid arthritis (RA) who have had an insufficient therapeutic response to or are intolerant of an adequate trial of first-line therapy, including full-dose nonsteroidal anti-inflammatory drugs (NSAIDs), or for children with active polyarticular juvenile idiopathic arthritis (pJIA).
Otrexup was approved by the FDA in October 2013. It is the only approved subcutaneous methotrexate product for once-weekly self-administration with a single-dose, disposable auto-injector.
Psoriasis is a chronic autoimmune skin disease that most commonly appears as raised, red patches with a white build-up of dead skin cells. The disease can affect skin on any part of the body. It occurs when the immune system sends out faulty signals that speed the growth cycle of skin cells.
Psoriasis is generally considered to be severe if it covers more than 5% to 10% of the body’s surface; to be recalcitrant when it does not adequately respond to treatment; and to be disabling when it interferes with basic functions, such as self-care, walking, and sleep.
Otrexup is a single-dose auto-injector containing methotrexate, which is used to treat certain adults with severe, active RA and children with active pJIA after treatment with other medications, including NSAIDS, have been used and did not work well. Methotrexate is also used to control the symptoms of severe, resistant, disabling psoriasis in adults when other types of treatment have been ineffective.
The device should not be used for the treatment of children with psoriasis.
The Otrexup auto-injector is self-administered (under the guidance and supervision of a physician) once-weekly in the abdomen or the thigh. The single-dose injector delivers 0.4 mL of methotrexate in the following dosage strengths: 10 mg, 15 mg, 20 mg, and 25 mg.
The recommended starting dose of methotrexate for adults with severe, recalcitrant psoriasis is a single weekly oral, intramuscular, subcutaneous, or intravenous dose of 10 to 25 mg. The starting dose for adults with RA is a single oral dose of 7.5 mg weekly, and the starting dose for children with pJIA is 10 mg/m2 once weekly.
Methotrexate interferes with DNA synthesis, repair, and cellular replication. Actively proliferating tissues, such as malignant cells, bone marrow, fetal cells, buccal and intestinal mucosa, and cells of the urinary bladder, are generally more sensitive to this effect of methotrexate.
In psoriasis, the rate of production of epithelial cells in the skin is greatly increased over that of normal skin. This differential in proliferation rates is the basis for the use of methotrexate to control the psoriatic process.
“As many as 7.5 million patients have psoriasis in the United States, and many of them have severe, disabling recalcitrant disease,” said Robert E. Kalb, MD, Clinical Professor of Dermatology at the State University of New York at Buffalo. “Methotrexate can be an important treatment option to consider when treating these patients. The greater bioavailability of subcutaneous methotrexate may provide benefits for many of these patients who have had an inadequate response to oral methotrexate due to either tolerability or efficacy.”