At November's meeting of the
Addressing the audience at the end of AAO's Retinal Subspecialty Day meeting, Genentech's president of product development, Susan Desmond-Hellmann, MD, said, "Genentech will not interfere with your prescribing choice, but we cannot jeopardize our commitment to tens of thousands of other patients who are counting on us to produce the medicines they need by risking [Food and Drug Administration] action against us … I want to reiterate that the decision wasn't made lightly, and we spent a lot of time weighing the impact of it." 
Pressed as to why the embargo is necessary, Dr. Hellmann recounted the events of a routine site inspection of the plant that manufactures Avastin that took place earlier this year. "During that [three-week long] inspection, something happened that was unprecedented: The inspector asked us for copies of the contracts we had with compounding pharmacies," she says. "The dialogue with the inspector also included quite a bit of discussion about the ophthalmic use of Avastin, as evidenced by the contracts." As a result, she says Genentech's regulatory experts, surprised by this line of questioning, felt the company had no choice but to destroy four lots of Avastin based on a higher standard the FDA was requiring of the company, especially regarding particulates in the formulation. They also "felt quite clearly that the FDA was not OK with Genentech supplying Avastin to compounding pharmacies," said Dr. Hellmann. She mentioned that the agency also sent a warning letter to a compounding pharmacy regarding the ophthalmic preparation of Avastin, which further increased Genentech's apprehension about renewing the contracts.
Dr. Hellmann maintains, however, that she feels ophthalmologists will still have access to Avastin after the embargo, though neither she nor company representatives present at the meeting could provide concrete reasons for the belief. "What we've understood, including from communications with compounding pharmacists, is that they will still be able to supply Avastin despite not having direct contracts with Genentech for it," Dr. Hellmann said. "So, it's not our intention to interfere with physicians using Avastin, we merely don't feel comfortable with the contracts with compounding pharmacists." A representative from the International Academy of Compounding Pharmacists, Joshua Wenderoff, was on hand to provide his organization's view of the embargo and Dr. Hellmann's confidence that ophthalmologists will still have access to Avastin. "We haven't had any communication with Genentech that would assure them it will be available from compounding pharmacists," he says. Though he adds that, "I've heard from some compounding pharmacies that there will be workarounds; they believe they will still be able to have access to Avastin." He didn't specify what form these workarounds might take. "I think the medical community seems committed to finding a way to preserve access to it," Mr. Wenderoff adds, "but the solution is unclear. We think the easiest way to ensure access is for Genentech to keep supplying compounding pharmacists with Avastin."
Test May Improve AMD Treatment Decisions
A computer-based method for evaluating the eye's ability to distinguish object details and shape in patients with age-related macular degeneration could provide a more accurate way to assess the effectiveness of eye surgery or vision rehabilitation interventions with devices and training, according to a Canadian study. The computer method could also vary low-, medium- and high-contrast illumination targets for testing spatial vision, which the authors say might be useful for early detection of AMD. The tests are described in "Computer-Based Test to Measure Optimal Visual Acuity in Age-Related Macular Degeneration," published in the October issue of Investigative Ophthalmology and Vision Science.
The researchers are associated with
"People with AMD rarely read or view things under optimal conditions, so this is not a test of how well they see in daily life," said Esther G. Gonzalez, one of the authors. "This test is designed to give vision rehabilitation practitioners a measure of the best visual acuity a person is capable of and in this sense it could be a useful tool for assessing rehabilitation progress."
In addition, the authors point out that patients with early AMD may demonstrate reduced function, not for the high-contrast, high-illumination targets of standard clinical acuity tests, but for medium- and low-contrast targets. They conclude that their computer method, which allows testing for targets of varying contrast, might help specialists detect AMD early. "Detection of potential visual acuity in patients with AMD is a crucial step in the clinical practice of vision rehabilitation. The ability to accurately estimate such potential will enhance results from vision rehabilitation," said Martin J. Steinbach, another author.
Vistakon Drug Iquix Enters Fluoroquinolone Market
Vistakon Pharmaceuticals has introduced Iquix (levofloxacin ophthalmic solution) 1.5% ocular anti-infective as the only newer-generation fluoroquinolone approved by the FDA for the treatment of corneal ulcers. Iquix, containing 1.5% levofloxacin, rapidly penetrates corneal tissue and provides broad coverage of the most sight-threatening gram-negative and the most prevalent gram-positive pathogens, including Corynebacterium species, Staphyloccus aureus, Staphyloccus epidermidis, Streptococcus pneumoniae, Viridans group streptococci, Pseudomonas aeruginosa and Serratia marcescens, Vistakon says.
"The introduction of Iquix marks a milestone in the treatment of corneal ulcers," says Penny A. Asbell, MD, professor of ophthalmology and director of Cornea Services, External Disease and Refractive Surgery at Mount Sinai School of Medicine in
Iquix eradicates targeted pathogens by inhibiting both topoisomerase IV and DNA gyrase, a dual mechanism of action similar to newer fluoroquinolones. Resistance to levofloxacin due to spontaneous mutation in vitro is a rare occurrence (10-9 to 10-10). Iquix is preservative-free. Levofloxacin, when tested in human cell cultures, demonstrated less cytotoxicity than other marketed fluoroquinolones, the company says.
Iquix is contraindicated in patients with a history of hypersensitivity to levofloxacin, to other quinolones, or to any of the components in this medication. Iquix was well-tolerated in clinical trials. The ocular adverse events occurring in 1 to 2 percent of patients included decreased/blurred vision, instillation site irritation/discomfort, ocular infection, and ocular pain/discomfort. The non-ocular adverse events occurring in approximately 8 to 10 percent of patients were headache and taste disturbance. For more complete information on warnings and precautions, please see the product insert, visit iquix.com or call 1 (800) 523-6225, option 2 & 3.
