Intrathecal Infusion (Prialt) for Severe Chronic Pain
On Dec. 28, the FDA approved ziconotide intrathecal (IT)
infusion (Prialt, made by Elan Corporation, plc), for the management
of severe chronic pain in patients for whom IT therapy is warranted,
and who are intolerant or refractory to other treatment, such as
systemic analgesics, adjunctive therapies, or IT morphine.
The non-narcotic agent is the synthetic equivalent of a
naturally occurring conopeptide found in a marine snail known as
Conus magus, and is thought to work by blocking N-type calcium
channels on nerves that transmit pain signals.
The approval was based on the results of three phase 3
clinical trials showing that ziconotide IT significantly reduced
chronic pain in a variety of opioid-resistant patient populations
with neuropathic pain and pain related to cancer and AIDS.
Adverse events were mild to moderate in intensity and
included dizziness, ataxia, confusion, and abnormal gait.
Ziconotide IT is approved for use only in the Medtronic
SynchroMed EL, SynchroMed II Infusion System, and
Simms Deltec Cadd Micro External Microinfusion Device and