Infliximab exerts a dose-dependent effect on retinal safety in the albino rabbit

Challenges for further successful development of tumor necrosis factor targeting therapies for uveitis

INTRODUCTION

Uveitis is a heterogeneous group of ocular conditions characterized by inflammation of the uveal tract and is one of the leading causes of vision impairment. In developed countries, noninfectious uveitis (NIU) represents most cases and is challenging to treat due to its severity, chronicity, and high recurrence rates. The advent of anti-tumor necrosis factor-α (anti-TNF-α) agents have dramatically improved outcomes and changed treatment paradigms in NIU.

AREAS COVERED

The index article summarizes the present experience of anti-TNF-α agents in NIU pharmacotherapy and highlights the barriers to further research and development of anti-TNF-α agents for uveitis. Common challenges faced in NIU clinical drugs trials, specific difficulties in anti-TNF-α drug development, and promising competitor drug candidates are discussed and evaluated.

EXPERT OPINION

Anti-TNF-α agents have revolutionized NIU pharmacotherapy and greatly improved outcomes with good safety profiles. The great success of systemic infliximab and adalimumab in NIU treatment has resulted in little impetus for further development of this class of medication. Attempts have been made to deliver anti-TNF-α agents intravitreally but that has not been successful thus far. With expiring patents, competition from biosimilars and newer, novel molecules, it may not be viable to continue pursuing anti-TNF-α drug development.

A comprehensive review of intravitreal immunosuppressants and biologicals used in ophthalmology

Systemic immunosuppressants and biologicals have been a valuable tool in the treatment of inflammatory diseases and malignancies. The safety profile of these drugs has been debatable, especially in localized systems, such as the eye. This has led to the search for fairly local approaches, such as intravitreal, subconjunctival, and topical route of administration. Immunosuppressants have been used as a second-line drug in patients intolerable to corticosteroids or those who develop multiple recurrences on weaning corticosteroids. Similarly, biologicals have also been used as the next line of therapy, when adequate control of inflammation could not be attained or immunosuppressants were contraindicated to patients. Intravitreal immunosuppressants, such as methotrexate and sirolimus, have been extensively studied in noninfectious posterior uveitis, whereas limited studies have established the efficacy of intravitreal biologicals, such as infliximab and adalimumab. Most of these drugs have shown good safety profile and tolerability in animal studies alone and have not been studied further in human subjects. However, most of the studies in literature are single-case reports or case series which limits the level of evidence. In this comprehensive review, we discuss the mechanism of action, pharmacodynamics, pharmacokinetics, indications, efficacy, and side effects of different intravitreal immunosuppressants and biologicals that have been studied in literature.