INTRODUCTION
Patients with chronic pain often struggle with opioid-related side
effects which bring to treatment suspension or failure.
Recently a low dose buprenorphine transdermal patch has been
introduced in Europe. The pharmacological features of buprenorphine
with less sedative effects and less addictive potential make this drug
an attractive choice for patients with chronic pain. We report the
results of low dose buprenorphine patch application on patients with
chronic pain and previous opioid exposure
MATHERIALS AND METHODS
We retrospectively analyzed 38 patients with chronic (> 3 months)
non-cancer pain who were prescribed low dose buprenorphine
transdermal patch. 24 patients were already on opioid medication and
discontinued their treatment for inefficacy or intolerable side effects,
they were given low dose buprenorphine patch as part of a standard
protocol of molecule rotation in case of failure of suspension, 14
patients were given buprenorphine as first opioid medication. We
evaluated pain (measured with NRS scale) at 1 month follow-up as well
as tolerability of medication.
RESULTS
All patients suffered from chronic pain of non oncologic origin, mainly
from joint osteoarthritis and low back pain. Baseline mean NRS of all
patients was 7.9 ± 2.3 At 1 month follow-up mean NRS significantly
decreased to 4.7 ± 2.3 (fig.2), 21/38 patients (55%) reported a pain
relief of > 50% from baseline. Regarding the adverse events 4/38
patients reported nausea, 5/38 confusion and just 2/38 constipation.
The starting dose was 5 mcg/h for 30 patients (fig.1), in 8 patients
buprenorphine was started at 10 mcg/h, those dosages were decided
considering previous opioid dosage, chronic renal failure and age. 6
patients stopped the treatment before 1 month follow-up for
intollerable side effects. The starting dosage of 5 mcg had to be raised
up to 10 mcg in 11 patients after the first follow up and in 2 patients
we reached 20 mcg/h (fig.1). In the subgroup of 24 patients with
previous opioid therapy (Fig.3) buprenorphine showed significant
efficacy with a mean NRS at 1 month of 4.7 ± 2.2 compared to 7.8 ±
1.2 at baseline, 14/24 (58%) patients reported more than 50% of pain
relief, with 80% of patients reporting a favourable outcome with 10
mcg/h dose which appeared to be the most effective dosage (fig.4).
Only 3/24 (12%) stopped medication due to side effects (nausea).
CONCLUSIONS
Buprenorphine patch was very well tolerated by the majority of patients, the incidence of adverse events was low and only 15% of patients stopped the medication for side effects. In patients with previous opioid therapy failure, even at low doses buprenorphine was efficient in reducing pain from baseline, in particular 80% of patients receiving 10 mcg/h were successful and 52% of those receiving the lowest dosage of 5 mcg/h experienced more than 50% pain relief 1 month after the beginning of treatment. Buprenorphine transdermal patch at low doses is a promising alternative to conventional opioid treatment, its efficacy and tolerability makes it a valid option for patients with severe chronic pain.

LOW DOSE BUPRENORPHINE PATCH FOR CHRONIC NON-CANCER PAIN IN PATIENTS WITH PREVIOUS OPIOID THERAPY FAILURE: TOLERABILITY AND EFFICACY