Study Shows Pregabalin Effective in Difficult-to-Treat Nerve Pain

Study Shows Pregabalin Effective in Difficult-to-Treat Nerve Pain

December 19, 2006

Results Offer Hope to Patients with Excruciating Chronic
Pain


    SYDNEY, Australia, Nov. 28 /Xinhua-PRNewswire/ --
Findings from a new 
study published today in the journal Neurology demonstrate
that the oral 
medication pregabalin is significantly effective in
relieving central 
neuropathic (nerve) pain and improves pain-related sleep
disturbance and 
anxiety in patients with spinal cord injury.  Conducted by
researchers at the 
Pain Management Research Institute in Sydney, the study is
the largest 
controlled clinical trial ever of patients with spinal cord
injury who suffer 
from central neuropathic pain, a particularly persistent
and severe pain 
condition.

    Results from the study showed that patients using
pregabalin (150-600 
mg/day) experienced significant improvements in symptoms as
early as the 
first week of treatment and those improvements were
sustained throughout the 
study.  Patients taking pregabalin experienced a
significant reduction in the 
average intensity of their pain and significant
improvements in pain-related 
sleep interference as well as a reduction in anxiety
compared to those taking 
placebo.

    "Historically it has been extremely difficult to
manage patients with 
central neuropathic pain due to a lack of effective
treatments and many 
people with spinal cord injury have excruciating
pain," said Prof. Philip 
Siddall, lead investigator of the study and Clinical
Associate Professor at 
the Pain Management Research Institute in Sydney. 
"The study demonstrates 
that pregabalin is an effective and well-tolerated therapy
for treating a 
range of symptoms that can negatively impact overall
quality of life.  This 
study is an important step forward for clinicians trying to
improve the lives 
of patients suffering from difficult-to-treat nerve
pains."

    Approximately two-thirds of patients with spinal cord
injury often suffer 
from severe central neuropathic pain(1,2), which is caused
by a lesion or 
dysfunction in the central nervous system(3).  Patients
often describe the 
symptoms of their pain as burning, tingling, stabbing,
shooting, pricking, 
scalding and freezing(4,5,6).  Chronic pain following
spinal cord injury may 
limit a patient's ability to perform daily activities(7). 
Consequently, 
quality of life may be impaired(8).  Central neuropathic
pain can occur in 
patients with spinal cord injury, stroke, multiple
sclerosis and neoplasia.

    Pregabalin is believed to work by calming hyper-excited
neurons or nerve 
cells which may be an underlying cause for various types of
nerve pain.

    Based on the results of this study, pregabalin recently
became the only 
therapy to receive European regulatory approval in central
neuropathic pain.

    About the Study

    The study, sponsored by pregabalin (Lyrica(R))
developer Pfizer Inc, was 
a multicentre, parallel-group, double-blind, randomised
clinical trial 
comparing pregabalin with placebo over a 12-week treatment
period in patients 
with spinal cord injury who had central neuropathic pain as
defined by the 
International Association for the Study of Pain
classification.  The 12-week 
treatment period was preceded by a 1-week baseline period
during which 
baseline data were collected.  Patients were randomised to
receive either 
flexible dose pregabalin (150-600 mg/day) (n=70) or placebo
(n=67) taken 
twice daily.  The primary endpoint of the study was mean
pain score as 
measured by patient pain diary assessments which were
completed daily.  
Patients also rated the extent to which pain interfered
with sleep in a daily 
diary.  Changes in anxiety were evaluated using the
Hospital Anxiety and 
Depression Scale (HADS).

    Results from the study showed that:

    * Patients receiving pregabalin experienced significant
improvements in 
      symptoms as early as the first week of treatment and
those improvements 
      were sustained throughout the study

    * Patients receiving pregabalin experienced a
significant reduction in   
      the average intensity of their pain and significant
improvements in 
      pain-related sleep interference (p<0.001) as well
as a reduction in 
      anxiety (p<0.05) compared to those taking placebo
(p<0.001)

    * More than 40 percent of patients had greater than a
30 percent 
      reduction in pain as compared to 16 percent of
patients on placebo 
      (p=0.001)

    * At the end of the study, three times less patients
had severe pain in 
      the pregabalin group compared with the placebo group

    * Pregabalin was associated with a rapid and
significant reduction in 
      pain-related sleep interference (p<0.001) as well
as a reduction in 
      anxiety (p<0.05) compared to those patients taking
placebo

    * The most common adverse events were somnolence and
dizziness, which 
      were typically mild to moderate and transient.

    About the Pain Management Research Institute

    The Pain Management Research Institute (PMRI) is headed
by Professor 
Michael Cousins and brings together around 40 researchers
and 40 clinical 
staff who are involved in pain research and management ( 
http://www.pmri.med.usyd.edu.au ).  The Institute also has
a strong focus on 
education and has a number of staff involved in the
delivery of a 
postgraduate degree program in Pain Management through the
University of 
Sydney.  This course is delivered on-line and accessible to
students 
internationally.  In 2004 the PMRI Educational Program
received an 
international award as an "Exemplary Educational
Program". Since 2005, the 
education program has been available to European and North
American students 
through collaborations with the University of Edinburgh and
the University of 
California, San Francisco.

    The pain research program of the PMRI has a broad scope
and has a number 
of teams investigating various aspects of pain
epidemiology, neurobiology, 
psychology and treatment and has gained international
recognition for its 
work in several areas including pain following spinal cord
injury.  In 1998, 
the Centre gained one of only eight National Health &
Medical Research 
Council (NHMRC) of Australia awards as a "Centre of
Clinical Excellence in 
Hospital Based Research".  In 2005, the PMRI, in
collaboration with the 
University of Queensland (Australia), University College
London (UK) and 
Nagasaki University (Japan) was a recipient of an NHMRC
Program Grant (2005-
2009).  Also in 2005 PMRI was the top level funded
institution for a Program 
Grant from the NSW Health to investigate "Mechanisms
and Treatment of Pain 
Associated with Spinal Cord Injury" (2005-2008).

    The Pain Management & Research Centre (PMRC) is the
clinical arm of the 
PMRI and conducts clinical treatment programs in acute
pain, cancer pain and 
chronic non cancer pain.  PMRC comprises a group of approx
40 
multidisciplinary health care practitioners who evaluate
all aspects of each 
patient's pain and recommend treatment options based upon a
multidisciplinary 
approach.  PMRC currently provides approx 40,000 episodes
of patient care per 
annum.  Each year at least four internationally funded
Fellows spend a year 
of training with PMRC.  To date Fellows have been drawn
from more than 20 
countries.

    1  Bonica JJ. Introduction: Semantic, epidemiologic and
educational 
       issues. In: Casey KL, ed. Pain and Central Nervous
System Disease. New 
       York: Raven Press, 1991:13-30.

    2  Siddall PJ, Taylor DA, McClelland JM, Rutkowski SB,
Cousins MJ. Pain 
       report and the relationship of pain to physician
factors in the first 
       6 months following spinal cord injury. Pain
1999;81(1-2):187-197.

    3  Merskey H, Bogduk N, eds. Classification of chronic
pain. Descriptions 
       of chronic pain syndromes and definitions of pain
terms. Seattle: IASP 
       Press, 1994:209-212.

    4  Cruz-Almeida Y, Martinez-Arizala A, Widerstrom-Noga
EG. Chronicity of 
       pain associated with spinal cord injury: a
longitudinal analysis. J 
       Rehabil Res Develop. 2005; 42(5):585-594.

    5  Finnerup N, Johannesen I, Fuglsang-Frederiksen A,
Bach FW, Jensen T. 
       Sensory function in spinal cord injury patients with
and without pain. 
       Brain. 2003; 126:57-70.

    6  Siddall P, McClelland JM, Rutkowski S, Cousins M. A
longitudinal study 
       of the prevalence and characteristics of pain in the
first 5 years 
       following spinal cord injury. Pain. 2003;
103:249-257.

    7  Ravensscroft A, Ahmed YS, Burnside IG. Chronic pain
after SCI: a 
       patient survey. Spinal Cord. 2000; 38:611-614.

    8  Stensman R. Adjustment to traumatic spinal cord
injury: a longitudinal 
       study of self-reported quality of life. Paraplegia.
1994; 32:416-422.




    For more information, please contact:

     Sejal Sedani
     Resolute Communications
     Tel:   [phone] x125
     Email: [e-mail]

     Lisa O'Sullivan
     Resolute Communications
     Tel:   [phone] x134
     Email: [e-mail]  


SOURCE  Pain Management Research Institute