Intrathecal Baclofen for Severe Spasticity: Longitudinal Data From the Product Surveillance Registry

Abstract

Objective: To assist in the assessment of intrathecal baclofen (ITB) therapy risks and benefits by providing surgical intervention rate, safety, and elective device replacement rate data. Materials and Methods: An ongoing prospective, long-term, multicenter Product Surveillance Registry (PSR) (NCT01524276) enrolled consented patients implanted with the SynchroMed II infusion system. Pump and catheter performance data were collected, with patients followed prospectively for events related to the device, procedure, and therapy. Investigators provided event descriptions, patient symptoms, and patient outcomes. Results: We analyzed registry data from 1743 patients (77% adult, 46.8% female) treated with ITB for severe spasticity at 53 registry sites between August 2003 and October 2017, for an accumulated 6481 patient-years. Discontinuation from the registry was largely (58.6% of discontinued patients) due to study site closure and patient relocation; exit due to an adverse event was limited to 0.3%. After 10 years, 87.2% of adult and 76.3% of pediatric patients continued with ITB. Overall, 99.1% of pumps reaching end of battery life were replaced at the time of explant. Conclusions: ITB therapy for the treatment of severe spasticity requires surgical implantation of a programmable infusion system for chronic drug delivery. If complications arise, many necessitate surgical intervention for correction. For spinal and cerebral spasticity in pediatric and adult patients, discontinuation rates due to an adverse event were low (0.3%), and there was high acceptance (99.1%) of surgical intervention for therapy continuation. Patient/caregiver willingness to accept surgical and other risks for therapy continuation was extremely high.

European expert consensus on improving patient selection for the management of disabling spasticity with intrathecal baclofen and/or botulinum toxin type A

“…cerebral palsy, acute brain injury, stroke) or spinal cord (e.g. spinal cord injury, multiple sclerosis) aetiology ( 1 , 2 ).…”

Targeted Drug Delivery for Chronic Nonmalignant Pain: Longitudinal Data From the Product Surveillance Registry

“…As previously reported (8,9,10), because the original intent of the registry was to monitor performance of the implanted infusion systems, reporting of device-related product performance issues has remained consistent throughout the course of the registry and across all patients enrolled. In 2010, the collection of safety data expanded to include all adverse events (AEs) related to implanted or external components of the infusion system, the implant procedure, or the infusion therapy; these events have only been collected for patients active in the registry or enrolled since that time.…”

“…As noted in earlier PSR publications ( 8 , 9 , 10 ), implanted, battery powered pumps eventually require replacement due to battery depletion. In the case of the SynchroMed II infusion system, the designed performance life is capped at 84 months, with a typical time to replacement of 75 months for the currently available infusion system.…”

“…The Medtronic Implantable Systems Performance Registry (ISPR; ClinicalTrials.gov Identifier: NCT01524276), initiated in 2003, is described by Konrad et al ( 8 ), Stearns et al ( 9 ), and Schiess et al ( 10 ). Results presented in these studies include product performance data collected under the ISPR protocol across all patients enrolled, data specific to patients enrolled for the treatment of cancer‐related pain, and data specific to patients enrolled for the treatment of severe spasticity, respectively.…”

“…In 2010, the collection of safety data expanded to include all adverse events (AEs) related to implanted or external components of the infusion system, the implant procedure, or the infusion therapy; these events have only been collected for patients active in the registry or enrolled since that time. Although not a prespecified outcome in the PSR, elective pump replacement was assessed here as a surrogate for patient satisfaction as reported in Schiess et al ( 10 ). The patients know that pump replacement requires surgery with a painful post‐surgical recovery period.…”