METHOXSALEN- methoxsalen capsule, liquid filled
Actavis Pharma, Inc.
(Soft Gelatin Capsules)
Rx Only
CAUTION: METHOXSALEN IS A POTENT DRUG. READ ENTIRE BROCHURE PRIOR TO PRESCRIBING OR DISPENSING THIS MEDICATION.
Methoxsalen with UV radiation should be used only by physicians who have special competence in the diagnosis and treatment of psoriasis and who have special training and experience in photochemotherapy. The use of Psoralen and ultraviolent radiation therapy should be under constant supervision of such a physician. For the treatment of patients with psoriasis, photochemotherapy should be restricted to patients with severe, recalcitrant, disabling psoriasis which is not adequately responsive to other forms of therapy, and only when the diagnosis is certain. Because of the possibilities of ocular damage, aging of the skin, and skin cancer (including melanoma), the patient should be fully informed by the physician of the risks inherent in this therapy.
CAUTION: Methoxsalen Capsules, USP (Soft Gelatin Capsules) should not be used interchangeably with regular methoxsalen capsules or methoxsalen hard gelatin capsules. This new dosage form of methoxsalen exhibits significantly greater bioavailability and earlier photosensitization onset time than previous methoxsalen dosage forms. Patient should be treated in accordance with the dosimetry specifically recommended for this product. The minimum phototoxic dose (MPD) and phototoxic peak time after drug administration prior to onset of photochemotherapy with this dosage form should be determined.
DESCRIPTION
Methoxsalen Capsules, USP (Soft Gelatin Capsules) 10 mg (8-methoxypsoralen). Methoxsalen, USP is a naturally occurring photoactive substance found in the seeds of the Ammi majus (Umbelliferae) plant and in the roots of Heracleum Candicans. It belongs to a group of compounds known as psoralens, or furocoumarins. The chemical name of methoxsalen, USP is 9-methoxy-7H-furo [3,2-g] [1] benzopyran-7-one
Each liquid filled soft-gelatin methoxsalen capsule contains 10 mg of Methoxsalen, USP and the following inactive ingredients: D&C yellow #10, FD&C blue #1, FD&C red #40, gelatin, glycerin, methylparaben sodium, polyethylene glycol, propylparaben sodium, purified water, sorbital sorbitan solution and titanium dioxide.
CLINICAL PHARMACOLOGY
The combination treatment regimen of psoralen (P) and ultraviolet radiation of 320 to 400 nm wavelength commonly referred to as UVA is known by the acronym, PUVA. Skin reactivity to UVA (320 to 400 nm) radiation is markedly enhanced by the ingestion of methoxsalen. In a well controlled bioavailability study, Methoxsalen Capsules, USP (Soft Gelatin Capsules) reached peak drug levels in the blood of test subjects between 0.5 and 4 hours (Mean = 1.8 hours) as compared to between 1.5 and 6 hours (Mean = 3.0 hours) for regular methoxsalen when administered with 8 ounces of milk. Peak drug levels were 2 to 3 fold greater when the overall extent of drug absorption was approximately two fold greater for Methoxsalen Capsules, USP (Soft Gelatin Capsules) as compared to regular methoxsalen capsules. Detectable methoxsalen levels were observed up to 12 hours post dose. The drug half-life is approximately 2 hours. Photosensitivity studies demonstrate a shorter time of peak photosensitivity of 1.5 to 2.1 hours vs. 3.9 to 4.25 hours for regular methoxsalen capsules. In addition, the mean minimal erythema dose (MED), J/cm2 , for the Methoxsalen Capsules, USP (Soft Gelatin Capsules) are substantially less than that required for regular methoxsalen capsules (Levins et al., 1984 and private communication1).
INDICATIONS AND USAGE
Photochemotherapy (Methoxsalen with long wave UVA radiation) is indicated for the symptomatic control of severe, recalcitrant, disabling psoriasis not adequately responsive to other forms of therapy and when the diagnosis has been supported by biopsy. Methoxsalen Capsules, USP (Soft Gelatin Capsules) are intended to be administered only in conjunction with a schedule of controlled doses of long wave ultraviolet radiation.
