Non-biodegradable ImplantRetisert

•For treatment of chronic, non-infectious uveitis (inflammation) including sympathetic ophthalmia. •3mm x 2mm x 5mm in size•Reservoir of flucinolone acetonide (corticosteroid thought to act by inducing phospholipase A2 inhib. proteins). 600ng a day decreasing to 300-400ng over the first month.•Inserted through the pars plana into the vitreous humour•Active for 2 and a half years•Removal can cause problems•SEs = Cataracts (observed in 90% of patients after 3 years), increased I.O pressure, eye pain, headache, nasopharyngitis and joint pain.

Retisert implants – A closer look•0.59mg tablet is held in a silicone elastomer cup.

•The release orifice is separated from the drugby a PVA membrane.

•The structure is held together with silicone glue

Top View

Side View

Silicone cup containing drug Release orifice

PVA structure tab

5mm

2mm

3mm

Uveitis treatment methods – pros and cons.

Pros Cons.

Retisert I.O implant Works for years once inserted – no problems with patient compliance.Sustained release of drug

Operation needed to insert/remove. High number of SEsDamage to implant could increase/decrease dose

I.O corticosteroid injection Less SEs than implants.More effective than drops.Injections needed less regularly than taking drops

Injections needed every few weeks- unplesant for patient.

Corticosteroid eye drops Easy application – no need for doctor.

Only effective for anterior uveitis.Difficult to maintain constant therapeutic levels

References• http://www.drugsmedia.com/pharmacology/fluocinolone_acetonide.html• http://www.bauschvrx.com/• http://www.engagesite.com/healthwork.html• http://www.rxlist.com/retisert-drug.htm• http://www.ema.europa.eu/docs/en_GB/document_library/Application_withdrawal_assess

ment_report/2010/01/WC500068245.pdf• http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002000/• http://emedicine.medscape.com/article/1209123-overview• http://www.nhs.uk/Conditions/Uveitis/Pages/Treatment.aspx• http://www.facebook.com/video/video.php?v=107311286140• http://medgadget.com/2009/02/eye_implant_prevents_lost_vision.html• http://www.uveitissociety.org/pages/diseases/so.html