Effects of topical diclofenac plus heparin (DHEP+H plaster) on somatic pain sensitivity in healthy subjects with a latent algogenic condition of the lower limb

Rationale and evidence for the incorporation of heparin into the diclofenac epolamine medicated plaster

OBJECTIVE

The nonsteroidal anti-inflammatory drug (NSAID) diclofenac epolamine (DHEP) formulated as a topical patch has demonstrated efficacy and safety in the localized treatment of acute pain from minor strains, sprains and contusions, and for epicondylitis and knee osteoarthritis. The glycosaminoglycan heparin enhances the activity of topical NSAIDs formulated as a medicated plaster, even in the absence of any significant release of heparin. Therefore, DHEP plus, a new formulation of the DHEP medicated plaster containing a small amount of heparin sodium as excipient, has been developed.

METHODS

We reviewed the pivotal and supportive studies of the clinical development program of the new patch and evaluated the role of heparin as an enhancer in the treatment of localized pain/inflammation of musculoskeletal structures, associated with post-traumatic and/or rheumatic conditions.

RESULTS

The data was consistent with the concept that heparin increased the clinical activity of the DHEP plus medicated plaster versus the reference DHEP medicated plaster through improved bioavailability due to enhanced movement of diclofenac from the plaster. Both DHEP formulations have the same dissolution profile, indicating that heparin does not change the physical and chemical characteristics of the plaster. Permeation testing showed that heparin is not released from the DHEP plus medicated plaster. Efficacy studies showed that the DHEP plus medicated plaster was significantly more effective in reducing pain than the reference marketed DHEP medicated plaster.

CONCLUSIONS

The benefit/risk assessment of DHEP plus 180 mg medicated plaster is favorable, with a safety profile equal to placebo and improved efficacy over the reference marketed DHEP medicated plaster.

Effects of topical vs injection treatment of cervical myofascial trigger points on headache symptoms in migraine patients: a retrospective analysis

Background

In migraine patients with cervical myofascial trigger points whose target areas coincide with migraine sites (M + cTrPs), TrP anesthetic injection reduces migraine symptoms, but the procedure often causes discomfort. This study evaluated if a topical TrP treatment with 3% nimesulide gel has similar efficacy as the injection but produces lesser discomfort with higher acceptability by the patients.

Methods

Retrospective analysis of medical charts of M + cTrPs patients in the period January 2012–December 2016 at a single Headache Center. Three groups of 25 patients each were included, all receiving migraine prophylaxis (flunarizine 5 mg/day) for 3 months and symptomatic treatment on demand. Group 1 received no TrP treatment, group 2 received TrP injections (bupivacaine 5 mg/ml at basis, 3rd, 10th, 30th and 60th day), group 3 received daily TrP topical treatment with 1.5 g of 3% nimesulide gel for 15 consecutive days, 15 days interruption and again 15 consecutive days. The following were evaluated: monthly number of migraine attacks and rescue medications, migraine intensity; pain thresholds to skin electrical stimulation (EPTs) and muscle pressure stimulation (PPTs) in TrP and target (basis, 30th, 60th and 180th days); discomfort from, acceptability of and willingness to repeat treatment (end of study). ANOVA for repeated measures and 1-way ANOVA were used to assess temporal trends in each group and comparisons among groups, respectively. Significance level was set at p < 0.05.

Results

Migraine improved over time in all groups, but significantly more and earlier in those receiving TrP treatment vs no TrP treatment (0.02 < p < 0.0001, 30–180 days for intensity and rescue medication, 60–180 days for number). All thresholds in the non-TrP-treated group did not change over time, while significantly improving in both the injection and nimesulide gel groups (0.01 < p < 0.0001, 30–180 days). Improvement of migraine and thresholds did not differ in the two TrP-treated groups. Discomfort was significantly lower, acceptability and willingness to repeat treatment significantly higher (0.05 < p < 0.0001) with gel than injection.

Conclusion

In migraine patients, topical treatment of cervical TrPs with 5% nimesulide gel proves equally effective as TrP injection with local anesthetics but more acceptable by the patients. This treatment could be effectively associated to standard migraine prophylaxis to improve therapeutic outcomes.