Efficacy of Bevacizumab (Avastin) in Treatment of Acute NMO Exacerbations

Subjects eligible for enrollment must meet all of the following criteria: 1. Able and willing to provide written informed consent. 2. 18-70 years of age. 3. New acute optic neuritis and/or transverse myelitis. A clinical event is defined as an episode of inflammation in the spinal cord and/or optic nerve leading to neurologic symptoms not ascribed to another disease process. 4. Known or suspected diagnosis of NMO according to the 2006 revisions of the Wingerchuk diagnostic criteria for NMO or AQP4 positive NMOSD per the EFNS Guidelines. For NMO, subjects must have two absolute criteria: 1. optic neuritis 2. myelitis and at least two of three supportive criteria: 3. presence of a contiguous spinal cord MRI lesion extending over three or more vertebral segments, 4. MRI criteria NOT satisfying the revised McDonald diagnostic criteria for MS \[Polman, 2011\] 5. NMO-IgG (AQP4) in serum. For NMOSD, subjects must have longitudinally extensive transverse myelitis (LETM) recurrent isolated optic neuritis (RION)/bilateral optic neuritis (BON), or opticospinal multiple sclerosis (OSMS) that is AQP4 antibody positive 5. A female subject is eligible to enter the study if she is: A. Not pregnant or nursing; B. Of non-childbearing potential (i.e. women who have had a hysterectomy, are postmenopausal, which is defined as \>2 years without menses (female subjects who have been post-menopausal for \<2 years must be confirmed with Follicle Stimulating Hormone (FSH) and estradi…