EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/76185
July 2012 EW NEWS & OPINION 3 The physician's art by J.C. Noreika, M.D. nal symptoms began post-op and had not a surgical resident invoked Woodward's aphorism regarding diagnostic zebras, she would have died from a perforated gastric volvulus. How we prepare and, especially, act in failure's presence helps us, the perfectly imperfect, burnish our best within T he soughing of an impa- tient audience, a stifling gymnasium, ear-drum piercing feedback of a microphone, the restive- ness of nameless academics … then, the inevitable strains of Sir Edward Elgar's Pomp and Circumstance March #1. For unfeigned eyeglazing, head-lolling, vertigo-inducing tedium, nothing matches the 27 minute pastiche known as the commencement address. You have heard it before. Or not. Some are noteworthy, even illustrious. David Foster Wallace's speech to the 2005 Kenyon College assemblage, for example, is a brilliant metaphorical distillation of life truths embracing empathy and understanding. On June 3, 2012, Atul Gawande delivered the address at Williams College. It was published as "Failure and Rescue" in The New Yorker magazine. Avoiding hoary exhortations of risk-taking, giving back, and persistence no matter, he speaks instead to failure. Failure happens. This may surprise Dr. Gawande's young Williams College audience. Yet his message is not to shock or deflate, but to prescribe. Dr. Gawande the writer/speaker is first and foremost a surgeon. He cleverly employs a case study: Mrs. C., 87 years old, an emi- gree from Nazi Germany, survivor of a World War II Shanghai ghetto, a widow at 44. With no formal education, she still did office work at Sears 3-and-a-half days a week. "She was sitting at her desk at Sears when the vision in her left eye went completely black." Mrs. C. presumably suffered a central retinal artery occlusion. Seen at the emer- gency room and diagnosed with carotid artery disease, she survived a successful endarterectomy. Abdomi- 3 ways to "fail to rescue" Her passing would have resulted from the euphemistic misfortune called "complications." It is not error in judgment, mistaken assump- tions, or bad karma that turn misfor- 4 CONTRAINDICATIONS The use of Durezol, as with other ophthalmic corticosteroids, is contraindicated in most active viral diseases of the cornea and conjunctiva including epithelial herpes simplex keratitis (dendritic keratitis), vaccinia, and varicella, and also in mycobacterial infection of the eye and fungal disease of ocular structures. HIGHLIGHTS OF PRESCRIBING INFORMATION These highlights do not include all of the information needed to use Durezol® safely and effectively. See full prescribing information for Durezol. DUREZOL® (difluprednate ophthalmic emulsion) 0.05% Initial U.S. approval: 2008 ---------------------------INDICATIONS AND USAGE------------------------ Durezol is a topical corticosteroid that is indicated for the treatment of inflammation and pain associated with ocular surgery. (1) ------------------------DOSAGE AND ADMINISTRATION-------------------- Instill one drop into the conjunctival sac of the affected eye(s) 4 times daily beginning 24 hours after surgery and continuing throughout the first 2 weeks of the postoperative period, followed by 2 times daily for a week and then a taper based on the response. (2) --------------------DOSAGE FORMS AND STRENGTHS---------------------- Durezol contains 0.05% difluprednate, as a sterile preserved ophthalmic emulsion for topical ophthalmic use only. (3) ----------------------------CONTRAINDICATIONS--------------------------- Durezol, as with other ophthalmic corticosteroids, is contraindicated in most viral diseases of the cornea and conjunctiva including epithelial herpes simplex keratitis (dendritic keratitis), vaccinia, and varicella, and also in mycobacterial infection of the eye and fungal diseases of ocular structures. (4) ------------------------WARNINGS AND PRECAUTIONS------------------------ • Intraocular pressure (IOP) increase - Prolonged use of corticosteroids may result in glaucoma with damage to the optic nerve, defects in visual acuity and fields of vision. If this product is used for 10 days or longer, IOP should be monitored. (5.1) • Cataracts - Use of corticosteroids may result in posterior subcapsular cataract formation. (5.2) • Delayed healing - The use of steroids after cataract surgery may delay healing and increase the incidence of bleb formation. In those diseases causing thinning of the cornea or sclera, perforations have been known to occur with the use of topical steroids. The initial prescription and renewal of the medication order beyond 28 days should be made by a physician only after examination of the patient with the aid of magnification such as slit lamp biomicroscopy and, where appropriate, fluorescein staining. (5.3) • Bacterial infections - Prolonged use of corticosteroids may suppress the host response and thus increase the hazard of secondary ocular infections. In acute purulent conditions, steroids may mask infection or enhance existing infection. If signs and symptoms fail to improve after 2 days, the patient should be re-evaluated. (5.4) • Viral infections - Employment of a corticosteroid medication in the treatment of patients with a history of herpes simplex requires great caution. Use of ocular steroids may prolong the course and may exacerbate the severity of many viral infections of the eye (including herpes simplex). (5.5) • Fungal infections - Fungal infections of the cornea are particularly prone to develop coincidentally with long-term local steroid application. Fungus invasion must be considered in any persistent corneal ulceration where a steroid has been used or is in use. (5.6) To report SUSPECTED ADVERSE REACTIONS, contact Alcon Laboratories, Inc. at 1-800-757-9195 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. See 17 for PATIENT COUNSELING INFORMATION. Revised date: March 2010 FULL PRESCRIBING INFORMATION: CONTENTS* 1 INDICATIONS AND USAGE 2 DOSAGE AND ADMINISTRATION 3 DOSAGE FORMS AND STRENGTHS 4 CONTRAINDICATIONS 5 WARNINGS AND PRECAUTIONS 5.1 IOP Increase 5.2 Cataracts 5.3 Delayed Healing 5.4 Bacterial Infections 5.5 Viral Infections 5.6 Fungal Infections 5.7 Topical Ophthalmic Use Only 6 ADVERSE REACTIONS 8 USE IN SPECIFIC POPULATIONS 8.1 Pregnancy 8.3 Nursing Mothers 8.4 Pediatric Use 8.5 Geriatric Use 11 DESCRIPTION 12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action 12.3 Pharmacokinetics 13 NONCLINICAL TOXICOLOGY 13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility 13.2 Animal Toxicology and/or Pharmacology 14 CLINICAL STUDIES 14.1 Postoperative Ocular Inflammation and Pain 16 HOW SUPPLIED/STORAGE AND HANDLING 17 PATIENT COUNSELING INFORMATION * Sections or subsections omitted from the full prescribing information are not listed. FULL PRESCRIBING INFORMATION 1 INDICATIONS AND USAGE Durezol (difluprednate ophthalmic emulsion) 0.05%, a topical corticosteroid, is indicated for the treatment of inflammation and pain associated with ocular surgery. 2 DOSAGE AND ADMINISTRATION Instill one drop into the conjunctival sac of the affected eye(s) 4 times daily beginning 24 hours after surgery and continuing throughout the first 2 weeks of the postoperative period, followed by 2 times daily for a week and then a taper based on the response. 3 DOSAGE STRENGTHS Durezol contains 0.05% difluprednate as a sterile preserved emulsion for topical ophthalmic administration. Difluprednate has a molecular weight of 508.56, and the empirical formula is C27H34F2O7. Each mL contains: ACTIVE: difluprednate 0.5 mg (0.05%); INACTIVE: boric acid, castor oil, glycerin, polysorbate 80, purified water, sodium acetate, sodium EDTA, sodium hydroxide (to adjust the pH to 5.2 to 5.8). The emulsion is essentially isotonic with a tonicity of 304 to 411 mOsm/kg. PRESERVATIVE: sorbic acid 0.1%. 5 WARNINGS AND PRECAUTIONS 5.1 IOP Increase Prolonged use of corticosteroids may result in glaucoma with damage to the optic nerve, defects in visual acuity and fields of vision. Steroids should be used with caution in the presence of glaucoma. If this product is used for 10 days or longer, intraocular pressure should be monitored. 5.2 Cataracts Use of corticosteroids may result in posterior subcapsular cataract formation. 5.3 Delayed Healing The use of steroids after cataract surgery may delay healing and increase the incidence of bleb formation. In those diseases causing thinning of the cornea or sclera, perforations have been known to occur with the use of topical steroids. The initial prescription and renewal of the medication order beyond 28 days should be made by a physician only after examination of the patient with the aid of magnification such as slit lamp biomicroscopy and, where appropriate, fluorescein staining. 5.4 Bacterial Infections Prolonged use of corticosteroids may suppress the host response and thus increase the hazard of secondary ocular infections. In acute purulent conditions, steroids may mask infection or enhance existing infection. If signs and symptoms fail to improve after 2 days, the patient should be re-evaluated. 5.5 Viral Infections Employment of a corticosteroid medication in the treatment of patients with a history of herpes simplex requires great caution. Use of ocular steroids may prolong the course and may exacerbate the severity of many viral infections of the eye (including herpes simplex). 5.6 Fungal Infections Fungal infections of the cornea are particularly prone to develop coincidentally with long-term local steroid application. Fungus invasion must be considered in any persistent corneal ulceration where a steroid has been used or is in use. Fungal culture should be taken when appropriate. 5.7 Topical ophthalmic use only Durezol is not indicated for intraocular administration. 6 ADVERSE REACTIONS Adverse reactions associated with ophthalmic steroids include elevated intraocular pressure, which may be associated with optic nerve damage, visual acuity and field defects, posterior subcapsular cataract formation, secondary ocular infection from pathogens including herpes simplex, and perforation of the globe where there is thinning of the cornea or sclera. Ocular adverse reactions occurring in 5–15% of subjects in clinical studies with Durezol included corneal edema, ciliary and conjunctival hyperemia, eye pain, photophobia, posterior capsule opacification, anterior chamber cells, anterior chamber flare, conjunctival edema, and blepharitis. Other ocular adverse reactions occurring in 1–5% of subjects included reduced visual acuity, punctate keratitis, eye inflammation, and iritis. Ocular adverse events occurring in < 1% of subjects included application site discomfort or irritation, corneal pigmentation and striae, episcleritis, eye pruritis, eyelid irritation and crusting, foreign body sensation, increased lacrimation, macular edema, scleral hyperemia, and uveitis. Most of these events may have been the consequence of the surgical procedure. 8 USE IN SPECIFIC POPULATIONS 8.1 Pregnancy Teratogenic Effects Pregnancy Category C. Difluprednate has been shown to be embryotoxic (decrease in embryonic body weight and a delay in embryonic ossification) and teratogenic (cleft palate and skeletal) anomalies when administered subcutaneously to rabbits during organogenesis at a dose of 1–10 μg/kg/day. The no-observed-effect-level (NOEL) for these effects was 1 μg/kg/day, and 10 μg/kg/day was considered to be a teratogenic dose that was concurrently found in the toxic dose range for fetuses and pregnant females. Treatment of rats with 10 μg/kg/day subcutaneously during organogenesis did not result in any reproductive toxicity, nor was it maternally toxic. At 100 μg/kg/day after subcutaneous administration in rats, there was a decrease in fetal weights and delay in ossification, and effects on weight gain in the pregnant females. It is difficult to extrapolate these doses of difluprednate to maximum daily human doses of Durezol, since Durezol is administered topically with minimal systemic absorption, and difluprednate blood levels were not measured in the reproductive animal studies. However, since use of difluprednate during human pregnancy has not been evaluated and cannot rule out the possibility of harm, Durezol should be used during pregnancy only if the potential benefit justifies the potential risk to the embryo or fetus. 8.3 Nursing Mothers It is not known whether topical ophthalmic administration of corticosteroids could result in sufficient systemic absorption to produce detectable quantities in breast milk. Systemically administered corticosteroids appear in human milk and could suppress growth, interfere with endogenous corticosteroid production, or cause other untoward effects. Caution should be exercised when Durezol is administered to a nursing woman. 8.4 Pediatric Use Safety and effectiveness in pediatric patients has not been established. 8.5 Geriatric Use No overall differences in safety or effectiveness have been observed between elderly and younger patients. 11 DESCRIPTION Durezol (difluprednate ophthalmic emulsion) 0.05% is a sterile, topical anti-inflammatory corticosteroid for ophthalmic use. The chemical name is 6α,9difluoro-11β,17,21-trihydroxypregna-1,4-diene-3,20-dione 21-acetate 17-butyrate (CAS number 23674-86-4). Difluprednate is represented by the following structural formula: tune into tragedy. It is the want of a plan that transmutes uncertainty into malfeasance. Dr. Gawande defined it a "failure to rescue." He cited work of researchers at the continued on page 8 12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Corticosteroids inhibit the inflammatory response to a variety of inciting agents that may delay or slow healing. They inhibit edema, fibrin deposition, capillary dilation, leukocyte migration, capillary proliferation, fibroblast proliferation, deposition of collagen, and scar formation associated with inflammation. There is no generally accepted explanation for the mechanism of action of ocular corticosteroids. However, corticosteroids are thought to act by the induction of phospholipase A2 inhibitory proteins, collectively called lipocortins. It is postulated that these proteins control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotreines by inhibiting the release of their common precursor arachidonic acid. Arachidonic acid is released from membrane phospholipids by phospholipase A2 Difluprednate is structurally similar to other corticosteroids. . 12.3 Pharmacokinetics Difluprednate undergoes deacetylation in vivo to 6α,9-difluoroprednisolone 17-butyrate (DFB), an active metabolite of difluprednate. Clinical pharmacokinetic studies of difluprednate after repeat ocular instillation of 2 drops of difluprednate (0.01% or 0.05%) QID for 7 days showed that DFB levels in blood were below the quantification limit (50 ng/mL) at all time points for all subjects, indicating the systemic absorption of difluprednate after ocular instillation of Durezol is limited. 13 NONCLINICAL TOXICOLOGY 13.1 Carcinogenesis, Mutagenesis, and Impairment of Fertility Difluprednate was not genotoxic in vitro in the Ames test, and in cultured mammalian cells CHL/IU (a fibroblastic cell line derived from the lungs of newborn female Chinese hamsters). An in vivo micronucleus test of difluprednate in mice was also negative. Treatment of male and female rats with subcutaneous difluprednate up to 10 μg/kg/day prior to and during mating did not impair fertility in either gender. Long term studies have not been conducted to evaluate the carcinogenic potential of difluprednate. 13.2 Animal Toxicology and/or Pharmacology In multiple studies performed in rodents and non-rodents, subchronic and chronic toxicity tests of difluprednate showed systemic effects such as suppression of body weight gain; a decrease in lymphocyte count; atrophy of the lymphatic glands and adrenal gland; and for local effects, thinning of the skin; all of which were due to the pharmacologic action of the molecule and are well known glucocorticosteroid effects. Most, if not all of these effects were reversible after drug withdrawal. The NOEL for the subchronic and chronic toxicity tests were consistent between species and ranged from 1–1.25 μg/kg per day. 14 CLINICAL STUDIES 14.1 Postoperative Ocular Inflammation and Pain Clinical efficacy was evaluated in 2 randomized, double-masked, placebo- controlled trials in which subjects with an anterior chamber cell grade ≥ "2" (a cell count of 11 or higher) after cataract surgery were assigned to Durezol or placebo (vehicle) following surgery. One drop of Durezol or vehicle was self instilled either 2 (BID) or 4 (QID) times per day for 14 days, beginning the day after surgery. The presence of complete clearing (a cell count of 0) was assessed 8 and 15 days post-surgery using a slit lamp binocular microscope. In the intent-to-treat analyses of both studies, a significant benefit was seen in the QID Durezol-treated group in ocular inflammation and reduction of pain when compared with placebo. The consolidated clinical trial results are provided below. Durezol QID (n = 107) Day Anterior Chamber cell clearing (% subjects) Pain free (% subjects) 8 24 (22%)* 62 (58%)* 15 44 (41%)* 67 (63%)* *Statistically significantly better than vehicle, p<0.01 16 HOW SUPPLIED/STORAGE AND HANDLING Durezol (difluprednate ophthalmic emulsion) 0.05% is a sterile, aqueous topical ophthalmic emulsion supplied in an opaque plastic bottle with a controlled drop tip and a pink cap in the following size: 5 mL in a 5 mL bottle (NDC 42826-601-05). Storage Store at 15-25°C (59-77°F). Do not freeze. Protect from light. When not in use keep the bottles in the protective carton. 17 PATIENT COUNSELING INFORMATION This product is sterile when packaged. Patients should be advised not to allow the dropper tip to touch any surface, as this may contaminate the emulsion. If pain develops or if redness, itching, or inflammation becomes aggravated, the patient should be advised to consult a physician. As with all ophthalmic preparations containing a preservative, patients should be advised not to wear contact lenses when using Durezol. Revised: March 2010 References: 1. Bikowski J, Pillai R, Shroot B. The position not the presence of the halogen in corticosteroids influences potency and side effects. J Drugs Dermatol. 2006;5(2):125-130. 2. Tajika T, Isowaki A, Sakaki H. Ocular distribution of difluprednate ophthalmic emulsion 0.05% in rabbits [published online ahead of print December 1, 2010]. J Ocul Pharmacol Ther. doi:10.1089/jop.2010.0093. 3. Ponec M, Kempenaar J, Shroot B, Caron JC. Glucocorticoids: binding affinity and lipophilicity. J Pharm Sci. 1986;75(10):973-975. 4. Korenfeld MS, Silverstein SM, Cooke DL, Vogel R, Crockett RS; Difluprednate Ophthalmic Emulsion 0.05% (Durezol) Study Group. Difluprednate ophthalmic emulsion 0.05% for postoperative inflammation and pain. J Cataract Refract Surg. 2009;35(1):26-34. 5. Fingertip Formulary. November 2010. Manufactured For Alcon Laboratories, Inc. 6201 South Freeway Fort Worth, Texas 76134 USA 1-800-757-9195 MedInfo@AlconLabs.com Manufactured By: Catalent Pharma Solutions Woodstock, IL 60098 ©2010 Alcon, Inc. 12/10 DUR11500JAD U.S. Patent No. 6,114,319 8 17 (7%) 59 (27%) Vehicle (n = 220) 15 25 (11%) 76 (35%)