Use of immunomodulators in non-infectious uveitis: lights and shadows.

Non-infectious uveitis (NIU) is one of the leading causes of sight impairment worldwide. Corticosteroids are the mainstay treatment for acute NIU, although their known systemic and ocular side effects limit their long-term use. The most common types of immunosuppressants used as steroid-sparing treatment are non-biologic drugs, particularly antimetabolites (methotrexate, mycophenolate mofetil, and azathioprine) and biologic drugs, mainly TNF-α inhibitors such as Adalimumab or Infliximab. Antimetabolites have shown their effectiveness in the treatment of NIU in individual and comparative studies, being methotrexate and mycophenolate mofetil usually preferred over azathioprine. The choice of which antimetabolite to use at first is not well defined, and decisions usually depend on the patient's characteristics and the physician's preferences. Treatment of NIU with biologic drugs, and particularly TNF-α inhibitors, has significantly increased in the last years and is considered an important alternative in patients not responding to first-line immunomodulators such as antimetabolites. However, data regarding how different immunomodulators or biologic drugs perform in different NIU is still limited, and little is known about the optimization of both biologic and non-biologic drugs when used in NIU. Further randomized clinical trials and comparative studies are required to achieve more understanding and better results when addressing complicated NIU. The purpose of this review is to provide a comprehensive overview of the use of non-biologic and biologic drugs in NIU, which may be useful for clinicians in their daily practice, and to address those aspects that are less known about these treatments as well as their weaknesses.