Rituximab also induces a release of some chronic lymphocytic leukemia cells from immune niches, which might make them more sensitive to chemotherapy used in combination with an anti-CD20 antibody.The combined effect results in the elimination of B cells (including the cancerous ones) from the body, allowing a new population of healthy B cells to develop from lymphoid stem cells. Standard treatment protocols of the lead compound rituximab result in rapid (within 3-7 days) and profound (≥90%) depletion of pre-B and mature B cells with full recovery taking as long as 12 months; serum immunoglobulin concentrations may be depleted for 5 to 12 months and may require substitution. Rituximab also leads to a reduced function of B cells as antigen presenting cells and, by increasing immature and transitional B cells, to a dysfunction of CD4+ T cells and abnormal cytotoxic T-cell-specific responses.Rituximab binds to amino acids 170–173 and 182–185 on CD20, which are physically close to each other as a result of a disulfide bond between amino acids 167 and 183.Rituximab is co-marketed by Biogen and Genentech in the U.S., by Hoffmann-La Roche in Canada and the European Union, Chugai Pharmaceuticals, Zenyaku Kogyo in Japan and AryoGen in Iran. History
Rituximab was developed by IDEC Pharmaceuticals under the name IDEC-C2B8. The U.S. patent for the drug was issued in 1998 and expired in 2015.Based on its safety and effectiveness in clinical trials, rituximab was approved by the U.S. Food and Drug Administration in 1997 to treat B-cell non-Hodgkin lymphomas resistant to other chemotherapy regimens.
Though respiratory compromise may not be immediately apparent in people with intermediate or mild NM, it often, but not always, exists to some extent. As in many neuromuscular disorders, hypoventilation can begin insidiously, and it may cause serious health problems if not remedied by the use of noninvasive mechanical devices to assist breathing, particularly at night. Communication and eating
Bulbar (throat) muscle weakness is a main feature of nemaline myopathy. Individuals with the most severe forms of NM are unable to swallow and receive their nutrition through feeding tubes. Most people with intermediate and mild NM take some or all of their nutrition orally. Bulbar muscle impairment may also lead to difficulty with communication. People with NM often have hypernasal speech as a result of poor closure of the velopharyngeal port (between the soft palate and the back of the throat). This may be able to be surgically corrected. Communicative skills may be enhanced through speech therapy, oral prosthetic devices, surgery, and augmentative communication devices. NM does not have any impact on cognition or intelligence. Physical characteristics and effects
Physical expression of nemaline myopathy varies greatly, but weakness is usually concentrated in the proximal muscles, particularly respiratory, bulbar and trunk muscles. People with severe NM show obvious symptoms at birth, while those with intermediate or mild NM may initially appear unaffected. Babies with NM are frequently observed to be "floppy" and hypotonic. Children born with NM often gain strength as they grow, though the effect of muscle weakness on body features may become more evident with time.