Efficacy and tolerability of DHEP-heparin plaster in reducing pain in mild-to-moderate muscle contusions: a double-blind, randomized trial

Systematic review of topical diclofenac for the treatment of acute and chronic musculoskeletal pain

Aim: The objective was to systematically review the efficacy and safety of topical diclofenac in both acute and chronic musculoskeletal pain in adults.Methods: We used standard Cochrane methods. Searches were conducted in MEDLINE, EMBASE and The Cochrane Register of Studies; date of the final search was November 2018. Included studies were randomized, double blinded, with ten or more participants per treatment arm. The primary outcome of "clinical success" was defined as participant-reported reduction in pain of at least 50%. Details of adverse events (AEs) were recorded.Results: For acute pain, 23 studies (5170 participants) were included. Compared to placebo, number needed to treat (NNT) for different formulations were as follows: diclofenac plaster, 4.7 (95% CI 3.7-6.5); diclofenac plaster with heparin, 7.4 (95% CI 4.6-19); and diclofenac Emulgel, 1.8 (95% CI 1.5-2.1). 4.1% (78/1919) reported a local AE. For chronic pain, 21 studies (26 publications) with 5995 participants were included. Formulations included gel, solution with or without DMSO, emulsion and plaster. A clinical success rate of ∼60% (NNT 9.5 [95% CI 7-14.7]) was achieved with a variety of formulations. Local AEs (∼14%) were similar for both diclofenac and placebo.Conclusion: This systematic review of 11,000+ participants demonstrates that topical diclofenac is effective for acute pain, such as sprains, with minimal AEs. The effectiveness of topical diclofenac was also demonstrated in chronic musculoskeletal pain but with a higher NNT (worse) compared with acute pain. Formulation does play a part in effectiveness but needs further studies.

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.

Efficacy and safety of topical diclofenac/menthol gel for ankle sprain: A randomized, double-blind, placebo- and active-controlled trial

Purpose

This study was performed to evaluate topical 1% diclofenac/3% menthol gel in treating ankle sprain.

Design

In this randomized, double-blind, placebo-controlled trial, adolescents and adults with acute ankle sprain (N = 385) applied 4 g of gel containing 1% diclofenac/3% menthol (n = 117), 1% diclofenac (n = 112), 3% menthol (n = 77), or placebo (n = 75) four times daily. The primary outcome was the area under the curve of pain intensity (PI) on movement [0 (no pain) to 10 (extreme pain)] from 24 to 72 hours post-application (AUC_{1–3 days}). Secondary outcomes included pain relief (PR); PI; time to onset of PR, meaningful PR, cooling, and complete recovery; PI difference; sum of PI difference; total PR; reduction in ankle swelling; and the patient’s global assessment of response to treatment.

Results

There were no statistically significant differences in AUC_1–3 between 1% diclofenac/3% menthol and placebo, diclofenac, or menthol gels and no meaningful advantages of 1% diclofenac/3% menthol for any secondary outcome. There was a higher incidence of skin and application-site events with 1% diclofenac/3% menthol than with placebo or 1% diclofenac.

Conclusion

No significant improvement was observed with topical 1% diclofenac/3% menthol gel compared with placebo, 1% diclofenac, or 3% menthol gel in treating pain from ankle sprain.

ClinicalTrials.Gov Identifier: NCT02100670

Topical NSAIDs for acute musculoskeletal pain in adults

BACKGROUND

Use of topical NSAIDs to treat acute musculoskeletal conditions has become widely accepted because they can provide pain relief without associated systemic adverse events. This review is an update of 'Topical NSAIDs for acute pain in adults' originally published in Issue 6, 2010.

OBJECTIVES

To determine the efficacy and safety of topically applied NSAIDs in acute musculoskeletal pain in adults.

SEARCH METHODS

We searched the Cochrane Register of Studies Online, MEDLINE, and EMBASE to February 2015. We sought unpublished studies by asking personal contacts and searching online clinical trial registers and manufacturers websites. For the earlier review, we also searched our own in-house database and contacted manufacturers.

SELECTION CRITERIA

We included randomised, double-blind, active or placebo (inert carrier)-controlled trials in which treatments were administered to adults with acute pain resulting from strains, sprains or sports or overuse-type injuries (twisted ankle, for instance). There had to be at least 10 participants in each treatment arm, with application of treatment at least once daily.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion, and extracted data. We used numbers of participants achieving each outcome to calculate the risk ratio and numbers needed to treat for an additional beneficial outcome (NNT) or additional harmful outcome (NNH) compared with placebo or other active treatment. We reported 95% confidence intervals (CI). We were particularly interested to compare different formulations (gel, cream, plaster) of individual NSAIDs.

MAIN RESULTS

For this update we added 14 new included studies (3489 participants), and excluded four studies. We also identified 20 additional reports of completed or ongoing studies that have not been published in full. The earlier review included 47 studies.This update included 61 studies. Most compared topical NSAIDs in the form of a gel, spray, or cream with a similar topical placebo; 5311 participants were treated with a topical NSAID, 3470 with placebo, and 220 with an oral NSAID. This was a 63% increase in the number of included participants over the previous version of this review. We also identified a number of studies in clinical trial registries with unavailable results amounting to about 5900 participants for efficacy and 5300 for adverse events.Formulations of topical diclofenac, ibuprofen, ketoprofen, piroxicam, and indomethacin demonstrated significantly higher rates of clinical success (more participants with at least 50% pain relief) than matching topical placebo (moderate or high quality data). Benzydamine did not. Three drug and formulation combinations had NNTs for clinical success below 4. For diclofenac, the Emulgel® formulation had the lowest NNT of 1.8 (95% CI 1.5 to 2.1) in two studies using at least 50% pain intensity reduction as the outcome. Diclofenac plasters other than Flector® also had a low NNT of 3.2 (2.6 to 4.2) based on good or excellent responses in some studies. Ketoprofen gel had an NNT of 2.5 (2.0 to 3.4), from five studies in the 1980s, some with less well defined outcomes. Ibuprofen gel had an NNT of 3.9 (2.7 to 6.7) from two studies with outcomes of marked improvement or complete remission. All other drug and formulation combinations had NNT values above 4, indicating lesser efficacy.There were insufficient data to compare reliably individual topical NSAIDs with each other or the same oral NSAID.Local skin reactions were generally mild and transient, and did not differ from placebo (high quality data). There were very few systemic adverse events (high quality data) or withdrawals due to adverse events (low quality data).

AUTHORS' CONCLUSIONS

Topical NSAIDs provided good levels of pain relief in acute conditions such as sprains, strains and overuse injuries, probably similar to that provided by oral NSAIDs. Gel formulations of diclofenac (as Emugel®), ibuprofen, and ketoprofen, and some diclofenac patches, provided the best effects. Adverse events were usually minimal.Since the last version of this review, the new included studies have provided additional information. In particular, information on topical diclofenac is greatly expanded. The present review supports the previous review in concluding that topical NSAIDs are effective in providing pain relief, and goes further to demonstrate that certain formulations, mainly gel formulations of diclofenac, ibuprofen, and ketoprofen, provide the best results. Large amounts of unpublished data have been identified, and this could influence results in updates of this review.

Topical use of antithrombotics: review of literature

While antithrombotics are usually administered intravenously, subcutaneously or orally, there are a number of publications reporting topical application of anticoagulation therapy. This paper aims to review the available literature regarding clinical conditions, the details of the topical antithrombotic treatment, as well as positive or adverse effects in an attempt to ascertain the safety and efficacy of this form of treatment. Published literature was searched to identify publications reporting the use of antithrombotic treatments administered via topical application between 1st January 1990 and 1st January 2013. There were 43 studies reported in 10 different clinical conditions. Majority of the studies were randomized controlled trials (51.2%), prospective studies (18.6%) or case reports (11.6%). The clinical conditions in which topical antithrombotics were administered included: microangiopathy, acute haemorrhoids, periodontitis, dermatitis, burns, ocular conditions and surgery, blunt force impact, scars, as well as clinical conditions associated with superficial venous thrombosis (SVT). The most commonly used topical antithrombotic was heparin (79.1% of studies). The respective dosage of different antithrombotics varied depending on specific clinical conditions. While most studies reported mean improvements or resolution of symptoms/condition in patients, the patient outcomes were variable. This review demonstrates that topical antithrombotic treatment is used according to a wide variety of protocols, with a subsequent variability in patient outcomes. Specific guidelines for the use of topical antithrombotics should be developed to standardize this form of treatment and ensure the best possible outcomes for patients.

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

OBJECTIVE

To evaluate whether a diclofenac epolamine + heparin topical (plaster) is more effective than diclofenac plaster alone in reducing deep somatic hyperalgesia in subjects without spontaneous pain and whether the effect is linked to or independent of the anti-edematous action of heparin.

DESIGN

Prospective, double-blind, randomized and controlled, four-arm parallel design trial.

SUBJECTS

One hundred and four patients (84 women, 20 men, mean age 42.2 ± 13.3 years), with deep somatic hyperalgesia in one thigh, randomly assigned to one of 4 groups of 26 each.

INTERVENTION

Each group underwent one of the following plaster treatments on one thigh: diclofenac+heparin; diclofenac; heparin; placebo, for 7 days, renewing the plaster every 24 hours.

OUTCOME MEASURES

Before treatment (day 1), at day 4 and day 8, assessment of (a) pressure and electrical pain thresholds of vastus lateralis and overlying subcutis and skin; and (b) structure/thickness of subcutis and muscle with ultrasounds at the same level.

RESULTS

During treatment, in placebo and heparin, no significant threshold changes, except subcutis thresholds which increased slightly (P < 0.02); in diclofenac and diclofenac+heparin, significant increase in all thresholds (0.0001 < P < 0.04). Electrical muscle pain thresholds increased significantly more in diclofenac+heparin than in diclofenac, heparin, and placebo (0.0001 < P < 0.04). In all groups: no edema and thickness changes at ultrasounds in muscle and subcutis.

CONCLUSIONS

Topical diclofenac+heparin is significantly more effective than diclofenac alone in reducing muscle hyperalgesia in subjects without spontaneous pain, independently of the anti-edematous action of heparin. The results provide a rationale for the use of diclofenac+heparin also in algogenic conditions without evident signs of injury/edema/hematoma.