A cerebrospinal fluid leak (CSF leak or CSFL) is a medical condition where the cerebrospinal fluid (CSF) surrounding the brain or spinal cord leaks out of one or more holes or tears in the dura mater. A cerebrospinal fluid leak can be either cranial or spinal, and these are two different disorders. A spinal CSF leak can be caused by one or more meningeal diverticula or CSF-venous fistulas not associated with an epidural leak.A CSF leak is either caused by trauma including that arising from medical interventions or spontaneously sometimes in those with predisposing conditions (known as a spontaneous cerebrospinal fluid leak or sCSF leak). Traumatic causes include a lumbar puncture noted by a post-dural-puncture headache, or a fall or other accident. Spontaneous CSF leaks are associated with heritable connective tissue disorders including Marfan syndrome and Ehlers–Danlos syndromes.A loss of CSF greater than its rate of production leads to a decreased volume inside the skull known as intracranial hypotension. Any CSF leak is most often characterized by orthostatic headaches, which worsen when standing, and improve when lying down. Other symptoms can include neck pain or stiffness, nausea, vomiting, dizziness, fatigue, and a metallic taste in the mouth. A CT myelography scan can identify the site of a cerebrospinal fluid leakage. Once identified, the leak can often be repaired by an epidural blood patch, an injection of the patients own blood at the site of the leak, a fibrin glue injection, or surgery.
The FDA said its approval of Zarxio is based on review of evidence that included structural and functional characterization, animal study data, human pharmacokinetic and pharmacodynamics data, clinical immunogenicity data and other clinical safety and effectiveness data that demonstrates Zarxio is biosimilar to Neupogen.In 2018, filgrastim-aafi (trade name Nivestym) was approved for use in the United States.In September 2008, Ratiograstim, Tevagrastim, Biograstim, and Filgrastim ratiopharm were approved for use in the European Union. Filgrastim ratiopharm was withdrawn in July 2011 and Biograstim was withdrawn in December 2016. In February 2009, Filgrastim Hexal and Zarzio were approved for use in the European Union.In June 2010, Nivestim was approved for use in the European Union.In October 2013, Grastofil was approved for use in the European Union.In September 2014, Accofil was approved for use in the European Union.In 2016, Fraven was approved for use by Republic of Turkey ministry of health.Nivestym was approved for medical use in Canada in April 2020.In October 2021, Nypozi was approved for medical use in Canada. Economics
Shortly after it was introduced, analyses of whether filgrastim is a cost-effective way of preventing febrile neutropenia depended upon the clinical situation and the financial model used to pay for treatment. The longer-acting pegfilgrastim may in some cases be more cost-effective. The introduction of biosimilars into the market resulted in a price reduction for the original, patent-protected product and increased use. References
Further reading
Santoso B, van Boxtel CJ, Edwards RI, eds. (2001). Drug benefits and risks: international textbook of clinical pharmacology. New York: Wiley. ISBN 0-471-89927-5. External links
"Filgrastim".