The authors of a case series reported in today's edition of JAMA Ophthalmology say silicone oil droplets from silicone used to lubricate the McKesson syringes is the most likely cause of the droplets presumed to cause the floaters. Of the 55 patients treated with Syfovre, 16 developed floaters.
Nearly one-third of patients treated with Syfovre (pegcetacoplan) injections for geographic atrophy developed symptomatic floaters, according to the case series published today in JAMA Ophthalmology. The authors believe they were caused by silicone oil droplets from silicone used to lubricate the syringe they used to administer the drug into the eye.
Sixteen of the 55 patients (29%) that they treated with Syfovre developed floaters, report Amr Dessouki, M.D., and his colleagues at Retinal Diagnostic Center in Campbell, California, outside of San Jose. Fourteen were symptomatic and all were found to have silicone oil droplets during biomicroscopic examination.
Dessouki and his colleagues said that aside from “inconvenience,” they had not observed “any immediate or substantial association between the floaters and these patients’ vision,” although they also report one of the affected patients is considering vitrectomy to remove the floaters and several patients report seeing hundreds of floaters.
The FDA approved Syfovre in February 2023. It is the first FDA-approved treatment for geographic atrophy.
Dessouki and his colleagues, who say they have reported their findings to the American Society of Retinal Specialists, say in their JAMA Ophthalmology report that the “most likely culprit” of the source of the silicone oil droplets are the McKesson 1-mL Luer lock syringes they used to administer Syfovre injections, They noted that they used the same model of syringe to administer Vabysmo (faricimab), a treatment for wet age-related macular degeneration, during the same period that they administered Syfovre injections and haven’t had comparable reports of floaters. They theorize that the viscosity of Syfovre may interact with the silicone lubricant in the syringe, noting that the “high viscosity of pegcetacoplan engendered copious amounts of air bubbles in the syringe so priming the syringe was crucial to ensure the smooth efflux of the medication during injection.”
Floaters were observed side effect in the DERBY and OAKS clinical trials of Syfovre, Dessouki and his colleagues, affecting approximately 1 in 10 patients, although they say they are unaware of any reports of silicone oil droplets.
“The difficulty of finding silicone-free Luer lock syringes may represent a challenge for the future use of the drug (Syfovre) because most syringes are manufactured with silicone oil to minimize friction during movement of the plunger,” Dessouki and his co-authors wrote in their conclusion.
They also noted that the incidence of silicone oil droplets may increase as newer intravitreal medications (such as Syfovre) appear to have increased viscosity.