VERTEPORFIN Drug Interactions: What You Need to Know

INTERACTIONS Drug interaction studies in humans have not been conducted with VISUDYNE. Verteporfin is rapidly eliminated by the liver, mainly as unchanged drug. Metabolism is limited and occurs by liver and plasma esterases. Microsomal cytochrome P450 does not appear to play a role in verteporfin metabolism. Based on the mechanism of action of verteporfin, many drugs used concomitantly could influence the effect of VISUDYNE therapy. Possible examples include the following: Calcium channel blockers, polymyxin B or radiation therapy could enhance the rate of VISUDYNE uptake by the vascular endothelium. Other photosensitizing agents (e.g., tetracyclines, sulfonamides, phenothiazines, sulfonylurea hypoglycemic agents, thiazide diuretics and griseofulvin) could increase the potential for skin photosensitivity reactions. Compounds that quench active oxygen species or scavenge radicals, such as dimethyl sulfoxide, β-carotene, ethanol, formate and mannitol, would be expected to decrease VISUDYNE activity. Drugs that decrease clotting, vasoconstriction or platelet aggregation, e.g., thromboxane A 2 inhibitors, could also decrease the efficacy of VISUDYNE therapy.

VISUDYNE (verteporfin for injection) is contraindicated for patients with porphyria or a known hypersensitivity to any component of this preparation [see Adverse Reactions ( 6 )] . VISUDYNE (verteporfin for injection) is contraindicated for patients with porphyria or a known hypersensitivity to any component of this preparation. ( 4 )

AND PRECAUTIONS

• Extravasation : If extravasation occurs, the infusion should be stopped immediately. The extravasation area must be thoroughly protected from direct light until swelling and discoloration have faded in order to prevent the occurrence of local burn. ( 5.1 )
• Exposure to Sun or Direct Light : Following injection with VISUDYNE (verteporfin for injection), care should be taken to avoid exposure of skin or eyes to direct sunlight or bright indoor light for 5 days. ( 5.2 )
• Anaphylactic Reactions : Immediately discontinue administration of VISUDYNE and initiate appropriate therapy if an anaphylactic or other serious allergic reaction occurs during or following infusion. ( 5.4 )

5.1 Local Adverse Reactions - Extravasation Standard precautions should be taken during infusion of VISUDYNE (verteporfin for injection) to avoid extravasation. Examples of standard precautions include, but are not limited to:

• A free-flowing intravenous (IV) line should be established before starting VISUDYNE infusion and the line should be carefully monitored.
• Due to the possible fragility of vein walls of some elderly patients, it is strongly recommended that the largest arm vein possible, preferably antecubital, be used for injection.
• Small veins in the back of the hand should be avoided. Extravasation of VISUDYNE, especially if the affected area is exposed to light, can cause severe pain, inflammation, swelling or discoloration at the injection site. Localized (skin) necrosis at the injection site following extravasation has also been reported. If extravasation does occur, the infusion should be stopped immediately. The extravasation area must be thoroughly protected from direct light until swelling and discoloration have faded in order to prevent the occurrence of local burn, which could be severe. Cold compresses should be applied to the injection site. Oral medications for pain relief may be administered.

5.2 Exposure to Sun or Direct Light Following injection with VISUDYNE (verteporfin for injection), care should be taken to avoid exposure of skin or eyes to direct sunlight or bright indoor light for 5 days. In the event of extravasation during infusion, the extravasation area must be thoroughly protected from direct light until the swelling and discoloration have faded in order to prevent the occurrence of a local burn which could be severe. If emergency surgery is necessary within 48 hours after treatment, as much of the internal tissue as possible should be protected from intense light.

5.3 Decreased Vision After Treatment Patients who experience severe decrease of vision of 4 lines or more within 1 week after treatment should not be retreated, at least until their vision completely recovers to pretreatment levels and the potential benefits and risks of subsequent treatment are carefully considered by the treating physician.

5.4 Anaphylactic Reactions Cases of anaphylactic reactions have been reported in patients receiving VISUDYNE. Medical supervision is recommended during infusion. If an anaphylactic or other serious allergic reaction occurs during or following infusion, administration of VISUDYNE should be discontinued immediately and appropriate therapy should be initiated.