Biomedical Engineering Reference
In-Depth Information
Table 12
(continued)
3.2.A
APPENDICES
3.2.A.1
Facilities and Equipment
3.2.A.2
Adventitious Agents Safety Evaluation
3.2.A.3
Novel excipients
3.2.R
REGIONAL INFORMATION
3.3
LITERATURE REFERENCES
7 Conclusions
Ophthalmic formulation development presents unique challenges
to formulation scientists. The design space for ophthalmic formula-
tions is constrained by safety, tolerability, regulatory, and market
requirements. The complex physiology and anatomy of the eye
limit the amount of drug that can be effectively delivered to intra-
ocular targets via the topical ocular route. As such, physicochemical
drug and formulation factors have a profound impact on the safety
and efficacy of ophthalmic formulations. Although ophthalmic
formulations are sterile products there are notable differences in
specifications and controls for ophthalmology drug products versus
parenteral drug products with respect to particulates, preservatives,
and packaging. Another defining challenge in ophthalmic product
development is the drug payload and posology. The instilled vol-
ume limitation (25-45
L) for topical ocular delivery as well as the
injection volume limitation (50-100
μ
L) for intraocular injection
severely limit the deliverable dose. Likewise, there is a practical
limitation on the number of eye drops that may be administered
and the frequency of dosing. Hence, the formulation impact on the
drug's pharmacokinetics and pharmacodynamics needs to be care-
fully investigated and optimized to ensure optimal delivery, safety,
and efficacy. This overview summarizes the design strategy of a
topical ophthalmic formulation particularly from the viewpoint of
CMC. A rationale-based formulation design approach should lead
to development of safe, stable, and efficacious ophthalmic formula-
tions meeting regulatory requirements.
μ
References
1. To be presented at US Pharmacopeial Forum 39
(5) Oct 2013 for inclusion into USP, section
<
Grossniklaus HE, Rittenhouse KD, Wilson
CG, Weber DA, Kuppermann BD, Csaky KG,
Olsen TW, Kompella UB, Holers VM,
Hageman GS, Gilger BC, Campochiaro PA,
Whitcup SM, Wong WT (2010) Ophthalmic
, Ophthalmic Preparations-Quality Tests
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771
>
