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Implantable MicroPump for Drug Delivery in Patients with Diabetic Macular Edema
Mark Humayun1, Arturo Santos2, Juan Carlos Altamirano2
1Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA.
Purpose:
To demonstrate the safety and surgical feasibility of the first-in-man ocular implant of a novel Posterior MicroPump Drug Delivery System (PMP) in patients with diabetic macular edema (DME) and to report on the device capabilities for delivering a programmable microdose.
Methods:
This was a single center, single arm, open-label, prospective study. Eleven patients with DME and visual acuity equal to or worse than 20/40 were included. The PMP prefilled with ranibizumab was implanted into the subconjunctival space. After implantation, the PMP was wirelessly controlled to deliver a programmed microdose. Comprehensive ophthalmic exams and optical coherence tomography were performed biweekly for 90 days. At the end of the study, the PMP was explanted and the subjects thereafter received standard of care for DME (i.e., laser or intravitreal injections).
Results:
All 11 surgical implantations were without complications and within the skill sets of a retinal surgeon. No serious adverse events occurred during the follow-up period. At no point were visual acuity and central foveal thickness worse than baseline in the implanted eye. The PMP delivered the programmed ranibizumab dosage in seven subjects. The remaining four patients received a lower than target dose, and the treatment was complemented with standard intravitreal injection.
Conclusions:
This study demonstrates the first-in-man safety of the Replenish MicroPump implant for a period of 90 days and its capability to deliver a microdose into the vitreous cavity. Further studies to enable longer-term safety and to demonstrate the feasibility of multiple programmable drug delivery are necessary.
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