Positive results in proof-of-concept study with OpsiSporin sustained release treatment for uveitis

Midatech Pharma (AIM: MTPH), a nanomedicine company developing and commercialising multiple therapeutic products to enhance the delivery of medicines in major diseases with high unmet medical needs, is pleased to announce positive results from a proof-of-concept in vivo study with OpsiSporin, a sustained release treatment for uveitis.

Uveitis is an inflammatory process affecting the iris, the ciliary body, the choroid layer or all or part of these structures of the eye. Whilst treatments exist, including corticosteroids and the immunosuppressant compound Cyclosporin A (CsA), a therapeutic that permanently controls inflammation, with a good short- and long-term safety profile, has yet to be developed.

OpsiSporin applies Midatech’s Q Sphera® microencapsulation technology platform to precisely encapsulate CsA within polymer microspheres for sustained and extended release. The product has the potential to offer an effective alternative to steroids for the treatment of uveitis and a concomitant reduction in associated adverse effects such as cataracts and glaucoma.

The in vivo preclinical study sought to determine the efficacy of OpsiSporin microspheres following a single intravitreal injection, in the treatment of autoimmune uveitis, compared with oral administration of CsA, an intravitreal microsphere suspension vehicle and untreated controls. Intravitreal injection, a technique by which a drug is injected into the eye, has become a common method of treatment for many retinal diseases including AMD, Diabetic Retinopathy, and Retinal Vein Occlusions.

Results of the study showed a significant reduction in the severity of the disease when intravitreal injection with 4.5µg OpsiSporin was compared with microsphere suspension vehicle. The study also demonstrated a comparable reduction in severity when a single intravitreal injection of 4.5µg OpsiSporin was compared to the daily oral administration of 6.7 mg/kg/day CsA (a dose more than one thousand-fold greater). These results show the potential of OpsiSporin to offer patients with autoimmune uveitis a therapeutic alternative to steroids and CsA with high efficacy and reduced adverse effects. 

Commenting on the results, Dr Jim Philips, CEO of Midatech Pharma, said: “The positive outcome of this proof-of-concept study is an important step forward in the development of a sustained release treatment for uveitis. The results showed OpsiSporin to be as efficacious as orally administered CsA at one thousandth of the dose, highlighting the significant value our microencapsulation technology can add to existing therapeutic molecules. We now look forward to progressing this product programme to the next stage with the aim of beginning clinical development as early as 2016.”