Evaluation of a novel formulation of Mitomycin C eye drops
3 October 2014Marina Castano1,2, Lynn Morrison1, Alexander B. Mullen2 1 GG&C NHS, Regional Quality Assurance Service, Stobhill Hospital, Glasgow, UK
2 University of Strathclyde, SIPBS, Glasgow, UK
Bespoke unlicensed medicines manufactured as "specials" often have quality attributes that are minimally qualified with little formal assessment of the benefits and risks associated with their clinical use.
Mitomycin C (MMC) is a cytotoxic antibiotic that is used as an unlicensed ophthalmic medicine in ocular surgery and the treatment of ocular malignancies. However, MMC has limited aqueous stability which restricts its clinical usage. For this reason, development of an innovative eye drop formulation with superior stability was pursued.
As part of the design package drug stability of the formulation was determined using a validated reverse phase HPLC method with samples tested periodically for 6 months. Cytotoxicity was evaluated in vitro with bioluminescent test, using a B16 luciferase melanoma proliferation assay.
From the results of the MMC stability test, the novel formulation represents a substantial improvement in shelf life of at least 6 months at 4°C compared to 6 weeks shelf life of the existing clinical formulation. The formulation retained more than 99% of original content in those conditions. A toxicological evaluation of the novel MMC eye drops showed that this formulation had a comparable profile to the aqueous MMC solution.
These findings will reduce manufacturing costs and extend patient access improving the treatment of several ocular pathologies. Ex vivo research to evaluate the ocular bioavailability of both formulations is underway.