Autoimmune diseases are making the headlines these days, with the reporting of results from clinical trial after clinical trial of various new treatments. Not surprisingly, such clinical trials have all been performed first for patients with systemic processes such as rheumatoid arthritis, Crohn disease, and multiple sclerosis rather than for isolated noninfectious uveitis. The reasons are simple. The overall number of uveitis patients is dwarfed by the numbers of patients with rheumatoid arthritis and other systemic diseases. There is an even smaller number of patients with any particular diagnostic entity of uveitis, each with a plethora of manifestations and differing severity. Finally, uveitis is essentially a medical subspecialty within a mainly surgical specialty, that of ophthalmology, and tends to be easily sidelined by mainstream ophthalmology just by sheer numbers. These reasons combine to create a formidable barrier to organizing, financing, and recruiting patients for randomized clinical trials (RCTs) in uveitis.
Okada AA. Noninfectious UveitisA Scarcity of Randomized Clinical Trials. Arch Ophthalmol. 2005;123(5):682-683. doi:10.1001/archopht.123.5.682