THE COMBINATION OF ZICONOTIDE TO INTRATHECAL BACLOFEN EFFECTIVELY AND SAFELY CONTROL NEUROPATHIC PAIN IN MULTIPLE SCLEROSIS: A CASE REPORT WITH A 4-YEAR FOLLOW UP

F. Gloria, M. Giglio, A. Corriero, A. Preziosa, F. Galdini, A. Pilolla, S. Grasso, F. Puntillo | Department of Interdisciplinary Medicine; ICU and Pain Therapy Section, University of Bari “Aldo Moro”

INTRODUCTION
Central neuropathic pain is a common symptom in multiple sclerosis (MS), with a prevalence of 86%, and most commonly presents as extremity pain, trigeminal neuralgia, back pain, or headache. Moreover, spasticity is very frequent in MS with similar incidence of neuropathic pain, further aggravating pain symptoms. The complex nature of such pain necessitates a multimodal approach for adequate treatment. The present case report describes a case of a MS patient with refractory neuropathic pain, in which the addition of ziconotide to an intrathecal (IT) combination of baclofen, and morphine allowed an efficacious pain control with no side effects.
METHODS
A 62-year lady was diagnosed MS with severe spasticity interesting lower limbs and implanted and IT pump for baclofen delivery in 2014. The catheter tip was located at midthoracic level, and the daily dose of baclofen was 260 mcg/die, with good clinical response. In 2021, she started complaining burning pain at T5-T9, bilaterally, with associated sensory losses, related to new demyelinating lesions at dorsal level. This neuropathic component of pain did not respond to high doses of anticonvulsant (gabapentin 1200 mg/day) or antidepressants (duloxetine 60 mg/day) and the patient complained of excessive drowsiness. An IT trial with morphine was therefore attempted, but no adequate pain control was obtained even with 1mg/day of IT morphine. Therefore, the addition of ziconotide was tried to obtain a better pain relief. An initial dose of 0.3 mcg/day of IT ziconotide was started, with gradual increase of 0.2 mcg/day every 2 weeks up to 1.1 mcg/day. At the same times morphine was reduced of 0.2 mg/day until its complete discontinuation at week eight. Also, oral gabapentin was stopped. The dose of intrathecal baclofen was maintained constant. The patient reported adequate pain control with no adverse effects and drowsiness resolution. The patient still maintains the same doses until today and reports no side effects.
DISCUSSION
The present case report confirms the clinical efficacy of ziconotide in central neuropathic pain and suggests that the combination of ziconotide to IT baclofen could be an effective strategy to control pain and spasticity in MS patients. Moreover, the slow titration protocol allows to control pain with no side effects. The long follow-up confirms the clinical efficacy and safety of this combination.
CONCLUSION
The combination of multiple IT drugs, with a careful titration protocol, could be an effective and safe strategy to control pain in MS.