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Riboflavin Supply
Riboflavin must be manufactured under fully aseptic conditions by a Class II GMP
accredited manufacturer. It is commercially and readily available as generic solution,
available from numerous manufacturers, which are all suitable for use with the
LightLink-CXL device. LightMed Corporation does not limit the physician the choice of
supplier for the Riboflavin use in conjunction with the LightLink-CXL on the same
commercial industry merits such that
-
In many markets globally Riboflavin is considered and registered as a device and
not a pharmaceutical agent, on merits that it acts as a filter protecting the retina
from UV-A light
-
Subsequently some markets do not recognize Riboflavin as a CE device but a
Pharmaceutical agent, hence some element of pharmacological action is present
during the procedure
It is thus essential and commercially feasible for LightMed not to limit itself nor its
customers to a choice of Riboflavin supplier, nor to enforce a bundle model as none of
the global manufacturers of Riboflavin at present fulfills a requirement of either a CE
(Device) or Pharmaceutical approvals on the same solution.
Mechanism of Action
The combination of riboflavin and ultraviolet irradiation induces a photo polymerization
process that increases the corneal biomechanical resistance through formation of new
inter fibrillar covalent bonds of the corneal collagen.
The UV-A activated riboflavin then stimulates production of singlet oxygen O
²
assisting in
a physical formation of new cross-linked bonds across adjacent collagen strands in the
stroma.
The irradiation of the riboflavin molecules by UV-A causes them to lose their internal
chemical balance, producing oxygen free radicals at which point, the riboflavin molecule
is unstable and becomes stable only when it is linked to two collagen fibrils. It creates a
crossed bridge between the collagen fibrils (cross-linking), thus producing a general
strengthening of the cornea.
Once “crossed bridged” is created between collagen fibrils (therefore the term:
“cross-linking”), it produces a rigidity increase of corneal layer.
Cross-links change several physic-chemical properties of collagen which is an indirect
evidence for cross-linking.
Summary of Contents for LightLink CXL
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