Device Slow-Release Formulations

The use of SRL has transcended from organ rejection prophylaxis to applications in medical devices owing to its effects of inhibiting lymphocyte and smooth muscle cell proliferation, which translate into suppression of neointimal hyperplasia [5]. Example devices include coronary artery stents, some of which are approved for patient care, and 

The Supralimus stent is a stainless steel SES with a biodegradable polymer mix of poly-L-lactide (PLA), polyvinyl pyrrolidone (PVP), poly(lactide-co-caprolactone) (PLC), and PLGA. The majority of SRL (-50%) is eluted during the first 9 days post-PCI, with complete stent depletion by day 48. The polymer matrix degrades over 7 months [11]. The Excel stent is likewise a stainless steel SES. It employs a PLLA as the biodegradable polymer which degrades in 6 to 9 months [8,11]. 

Supralimus-Core is based upon a cobalt-chromium metal stent and uses the polymer combination of PLA, 50/50 poly(D,L-lactide-co-glycolide) and polyvinyl pyrrolidone [9,14]. About 70% of drug is released within 7 days of implantation, with the remaining drug released over a period of 48 days. 

DBS System / Manufacturer Stent Material Polymer / Bio absorption (months) Sirolimus Content Sirolimus Release (%, days) 

Supralimus / Sahajanand Medical Technologies, Gujrat, India Stainless steel PLEA, PLCA, PEC, PVP (7) 125 pg/19 mm 50%, 9-11 100%, 41 

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