PORFIMER Drug Interactions: What You Need to Know

INTERACTIONS Other Photosensitizing Agents : May increase the risk of photosensitivity reaction ( 7.1 )

7.1 Use with Other Photosensitizing Agents PHOTOFRIN can cause photosensitivity. The concomitant use of PHOTOFRIN with other photosensitizing agents (e.g., tetracyclines, sulfonamides, phenothiazines, sulfonylurea hypoglycemic agents, thiazide diuretics, griseofulvin, and fluoroquinolones) may increase the risk of a photosensitivity reaction. Avoid the concomitant use of PHOTOFRIN with other products known to cause photosensitivity.

PHOTOFRIN is contraindicated in patients with porphyria. Photodynamic therapy (PDT) is contraindicated in patients with an existing tracheoesophageal or bronchoesophageal fistula. PDT is contraindicated in patients with tumors eroding into a major blood vessel. PDT is not suitable for emergency treatment of patients with severe acute respiratory distress caused by an obstructing endobronchial lesion because 40 to 50 hours are required between injection with PHOTOFRIN and laser light treatment. PDT is not suitable for patients with esophageal or gastric varices, or patients with esophageal ulcers >1 cm in diameter. Porphyria ( 4 ) Existing tracheoesophageal or bronchoesophageal fistula ( 4 , 5.1 ) Tumors eroding into a major blood vessel ( 4 , 5.2 ) Emergency treatment of patients with severe acute respiratory distress caused by an obstructing endobronchial lesion because 40 to 50 hours are required between injection of PHOTOFRIN and laser light treatment ( 4 ) Esophageal or gastric varices or esophageal ulcers >1 cm in diameter ( 4 )

AND PRECAUTIONS Gastroesophageal Fistula and Perforation : Do not initiate PHOTOFRIN with photodynamic therapy (PDT) in patients with esophageal tumors eroding into the trachea or bronchial tree or bronchial wall. ( 5.1 ) Pulmonary and Gastroesophageal Hemorrhage : Assess patients for tumors eroding into a pulmonary blood vessel and esophageal varices. Do not administer light directly to an area with esophageal varices. ( 5.2 ) High-Grade Dysplasia (HGD) in Barrett’s Esophagus (BE) : After treatment of HGD in BE, conduct endoscopic biopsy surveillance every 3 months, until 4 consecutive negative evaluations for HGD have been recorded. ( 5.3 ) Photosensitivity and Ocular Photosensitivity : Observe precautions to avoid exposure of skin and eyes to direct sunlight or bright indoor light for at least 30 days. Instruct patients when outdoors to wear dark sunglasses which have an average light transmittance of <4% for at least 30 days and until ocular sensitivity resolves. ( 5.4 , 5.5 )

Use

Before or After Radiotherapy : Allow 2-4 weeks between PDT and subsequent radiotherapy. ( 5.6 )

Chest

Pain : Substernal chest pain can occur ( 5.7 )

Airway

Obstruction and Respiratory Distress : Administer with caution to patients with tumors in locations where treatment- induced inflammation can obstruct the main airway. Monitor patients closely between the laser light therapy and the mandatory debridement bronchoscopy for any evidence of respiratory distress. ( 5.8 )

Esophageal

Strictures : Esophageal strictures can occur ( 5.9 ) Hepatic and Renal Impairment : Patients with hepatic or renal impairment may need longer precautionary measures for photosensitivity. ( 5.10 ) Thromboembolism : Thromboembolic events can occur. ( 5.11 ) Embryo-Fetal Toxicity : May cause embryo-fetal toxicity. Advise females of reproductive potential of the potential risk to a fetus and to use effective contraception. ( 5.12 , 8.1 )

5.1 Gastroesophageal Fistula and Perforation Serious and sometimes fatal gastrointestinal and esophageal necrosis and perforation can occur following treatment with PHOTOFRIN with PDT. Do not initiate PHOTOFRIN with PDT in patients with esophageal tumors eroding into the trachea or bronchial tree or bronchial wall because of the high likelihood of tracheoesophageal or bronchoesophageal fistula.

5.2 Pulmonary and Gastroesophageal Hemorrhage Patients with large, centrally located tumors, cavitating tumors, or extensive tumors extrinsic to the bronchus are at high risk for fatal massive hemoptysis. Assess patients for tumors eroding into a pulmonary blood vessel [ see Contraindications ( 4 )] and esophageal varices. Do not administer light directly to an area with esophageal varices because of the high risk of hemorrhage.

5.3 High-Grade Dysplasia (HGD) in Barrett’s Esophagus (BE) The long-term effect of PDT on HGD in BE is unknown. There is always a risk of cancer or abnormal epithelium that is invisible to the endoscopist beneath the new squamous cell epithelium; these facts emphasize the risk of overlooking cancer in such patients and the need for rigorous continuing surveillance despite the endoscopic appearance of complete squamous cell reepithelialization. Conduct endoscopic biopsy surveillance every 3 months, until 4 consecutive negative evaluations for HGD have been recorded; further follow-up may be scheduled every 6 to 12 months, as per judgment of healthcare providers. The follow-up period of the randomized study at the time of analysis was a minimum of 2 years (range 2 to 5.6 years).

5.4 Photosensitivity All patients who receive PHOTOFRIN will be photosensitive and must observe precautions to avoid exposure of skin and eyes to direct sunlight or bright indoor light (from examination lamps, including dental lamps, operating room lamps, unshaded light bulbs at close proximity, etc.) for at least 30 days. Some patients may remain photosensitive for up to 90 days or more. The photosensitivity is due to residual drug, which will be present in all parts of the skin. Exposure of the skin to ambient indoor light is, however, beneficial because the remaining drug will be inactivated gradually and safely through a photobleaching reaction. Therefore, patients should not stay in a darkened room during this period and should be encouraged to expose their skin to ambient indoor light. The level of photosensitivity will vary for different areas of the body, depending on the extent of previous exposure to light. Before exposing any area of skin to direct sunlight or bright indoor light, the patient should test it for residual photosensitivity. A small area of skin should be exposed to sunlight for 10 minutes. If no photosensitivity reaction (erythema, edema, blistering) occurs within 24 hours, the patient can gradually resume normal outdoor activities, initially continuing to exercise caution and gradually allowing increased exposure. If some photosensitivity reaction occurs with the limited skin test, the patient should continue precautions for another 2 weeks before retesting. The tissue around the eyes may be more sensitive, and therefore, it is not recommended that the face be used for testing. If patients travel to a different geographical area with greater sunshine, they should retest their level of photosensitivity. Conventional ultraviolet (UV) sunscreens will only protect against UV light-related photosensitivity and will be of no value in protecting against induced photosensitivity reactions caused by visible light.

5.5 Ocular Sensitivity Sensitivity to sun, bright lights, or car headlights, causing ocular discomfort, can occur in patients who receive PHOTOFRIN. For at least 30 days and until ocular sensitivity resolves, instruct patients when outdoors to wear dark sunglasses which have an average white light transmittance of &lt;4%.

5.6 Use Before or After Radiotherapy If PDT is to be used before or after radiotherapy, allot sufficient time between the two therapies to ensure that the inflammatory response produced by the first treatment has subsided before commencing the second treatment. The inflammatory response from PDT will depend on tumor size and extent of surrounding normal tissue that receives light.

Allow

2 to 4 weeks after PDT before commencing radiotherapy. The acute inflammatory reaction from radiotherapy usually subsides within 4 weeks after completing radiotherapy.

Allow

4 weeks after completing radiotherapy before commencing PDT.

5.7 Chest Pain As a result of PDT treatment, patients may complain of substernal chest pain because of inflammatory responses within the area of treatment. Such pain may be of sufficient intensity to warrant the short-term prescription of opiate analgesics.

5.8 Airway Obstruction and Respiratory Distress PHOTOFRIN followed by PDT can cause treatment-induced inflammation and obstruct the main airway. Administer with caution to patients with endobronchial tumors in locations where treatment-induced inflammation can obstruct the main airway, e.g., long or circumferential tumors of the trachea, tumors of the carina that involve both mainstem bronchi circumferentially, or circumferential tumors in the mainstem bronchus in patients with prior pneumonectomy. Monitor patients closely between the laser light therapy and the mandatory debridement bronchoscopy for any evidence of respiratory distress. Inflammation, mucositis, and necrotic debris may cause obstruction of the airway. If respiratory distress occurs, the physician should be prepared to carry out immediate bronchoscopy to remove secretions and debris to open the airway.

5.9 Esophageal Strictures Esophageal strictures occurred in 122 of 318 (38%) patients enrolled in three clinical studies of patients who received PHOTOFRIN with PDT to the esophagus. Nodule pretreatment and re-treating the same mucosal segment more than once may influence the risk of developing an esophageal stricture. A total of 49% of patients who developed a stricture received nodule pretreatment and 82% who developed a stricture had a mucosal segment treated twice. Overall, esophageal strictures occurred within six months following PHOTOFRIN with PDT. Multiple dilations of esophageal strictures may be required, as shown in Table 5 TABLE 5 .

Esophageal

Dilations in Patients with Treatment – Related Strictures Number of Dilations Number of Patients With Strictures N=114 Percentage of Patients with Strictures 1 – 2 Dilations 32 28% 3 – 5 Dilations 32 28% 6 - 10 24 21% >10 Dilations 26 23%

5.10 Risk of Prolonged Duration of Photosensitivity in Patients with Hepatic and Renal Impairment Hepatic or renal impairment will likely prolong the elimination of porfimer sodium leading to higher rates of toxicity. Inform patients with severe renal impairment or mild to severe hepatic impairment that the period requiring the precautionary measures for photosensitivity may be longer than 90 days.

5.11 Thromboembolism Thromboembolic events can occur following photodynamic therapy with PHOTOFRIN. Most reported events occurred in patients with other risk factors for thromboembolism including advanced cancer, following major surgery, prolonged immobilization, or cardiovascular disease.

5.12 Embryo-Fetal Toxicity Based on animal studies, PHOTOFRIN may cause embryo-fetal toxicity when administered to a pregnant woman. Intravenous administration of porfimer sodium to pregnant rats and rabbits during the period of organogenesis at dose levels approximately 0.64 times the recommended human dose of PHOTOFRIN based on body surface area (BSA) resulted in increased fetal resorptions, decreased litter size, and reduced fetal weight but did not cause fetal malformations. Advise pregnant women of the potential risk to fetus. Advise females of reproductive potential and males with female partners of reproductive potential to use effective contraception during treatment with PHOTOFRIN and for 5 months after the final dose.