Pilot study of topical delivery of methotrexate by electroporation

Self-assembled hyaluronic acid nanoparticles delivered by polymeric microneedles for targeted and long-acting therapy of psoriasis

Psoriasis is an autoimmune-driven inflammatory skin disease, clinically characterized by skin thickening, erythema, and scaling, significantly impacting patients' life quality and mental health. Clinically, oral pill or injection of methotrexate (MTX) formulation is a common route for psoriasis therapy, while both methods often cause undesired toxicity due to systemic administration, and limit patient compliance because of the frequent-dosing requirement. Here, we introduce a dissolvable microneedle (MN) patch made of polyvinyl alcohol (PVA) that incorporates self-assembled hyaluronic acid (HA) nanoparticles (NPs) conjugating MTX, which is designed for treating skin diseases, offering reduced adverse effects and improved patient adherence through its targeted and long-acting properties. Upon transdermal delivery via polymeric MNs, the HA-based therapeutic NPs actively target to the inflammatory skin cells via the interaction of HA group with CD44 protein that is highly expressed on the cell membrane in the psoriatic skin. Moreover, the HA-based NPs undergo slow dissociation, thereby achieving sustained release of the MTX drug at the lesion site over 7 days. Due to the favorite features, in the imiquimod (IMQ)-induced psoriatic mouse, only one application of the polymeric MN patch achieves diminished epidermal hyperplasia, and reduced inflammatory factors expression, ultimately improving the psoriasis-like skin condition in vivo.

Electrostimulation: A Promising New Treatment for Psoriasis

Psoriasis is a chronic inflammatory skin disease caused by abnormal activation and immune system disorder. Despite the availability of several treatments, they only provide temporary relief, and there is a critical need for more effective therapies to manage this condition. Electrostimulation has been widely used as a physical stimulus in treating various diseases, and recent studies have shown its potential in psoriasis treatment. In this review, we explore the direct and indirect effects of electrostimulation in treating psoriasis and their underlying mechanisms (the decreased secretion of inflammatory cytokines, the loss of cell-to-cell connections, and the cAMP signaling pathway). Our findings suggest that electrostimulation therapy may offer a promising approach to treating psoriasis and developing wearable devices for its management.

Dissolving microneedle patch-assisted transdermal delivery of methotrexate improve the therapeutic efficacy of rheumatoid arthritis

Methotrexate (MTX) is a first-line treatment for rheumatoid arthritis (RA), but its clinical use is greatly limited by the adverse effects and poor patient compliance caused by traditional oral administration or injection. In recent years, some transdermal drug delivery systems have received considerable attention due to overcoming these shortcomings. In this study, we developed dissolving microneedle patch (DMNP) for transdermal delivery of MTX to treat RA safely and effectively. The morphology, mechanical strength, skin insertion, drug content, in vitro transdermal delivery, and other properties of DMNP were characterized. Meanwhile, the adjuvant-induced arthritis model of rats was established to investigate the therapeutic effect of MTX-loaded DMNP in vivo. The results showed that the microneedles had excellent morphology with neat array and complete needles, good puncture performance and mechanical strength, and rapid intradermal dissolution rate. In vitro transdermal delivery results indicated that microneedles could significantly increase drug transdermal permeation compared with the cream group. The pharmacological study showed that MTX-loaded DMNP significantly alleviated paw swelling, inhibit inflammatory response via downregulating the levels of TNF-α and IL-1β, relieved synovium destruction with less cartilage erosion, and slowed the progression of RA in AIA rats. Besides, DMNP presented better therapeutic performance than cream or intragastric administration at the same dosage of MTX. In conclusion, the MTX-loaded dissolving microneedle patch has advantages of safety, convenience, and high efficacy over conventional administrations, laying a foundation for the transdermal drug delivery system treatment of rheumatoid arthritis.

Influences of methotrexate iontophoresis on functional lifestyle disabilities, functional capacity, and pain in patients with plantar psoriasis

Objectives

This study was aimed to evaluating the influences of methotrexate iontophoresis on functional lifestyle disabilities, functional capacity, and pain after a 6-min walking distance (6MWD) test in patients with plantar psoriasis (PP).

Patients and methods

Forty‑five patients (29 females, 16 males; mean age 33.9±6.6 years; range, 20 to 45 years) with hyperkeratotic PP were enrolled in the randomized, placebo-controlled, parallel-groups, double-blinded study. They were assigned randomly into the active methotrexate iontophoresis (MI) group (n=23) and the placebo iontophoresis group (n=22). The patients in both groups were assessed before starting the treatment intervention and after completing eight sessions of the treatment intervention through functional lifestyle disabilities measured on the Arabic version of psoriasis disability index, functional capacity using the 6MWD test, and pain after the 6MWD test.

Results

The pre-treatment measurements of the three variables among the two groups did not reveal statistically significant differences (p>0.05). However, there were statistically significant differences in the post-treatment results between the two groups (p<0.05). Additionally, the pre-and post-treatment values of the three outcome measures revealed statistically significant differences within the MI group (p<0.05). In contrast, there were no significant differences within the placebo group (p>0.05).

Conclusion

Methotrexate iontophoresis is effective in improving functional lifestyle disabilities, enhancing functional capacity, and decreasing pain in patients with PP.

Topical methotrexate in dermatology: a review of the literature

Background: Systemic methotrexate (MTX) is a useful treatment for many dermatologic conditions, however, the risk of adverse events prevents its use in patients with minimal or localized disease. Topical application of MTX may be an option to avoid the systemic adverse effects of oral MTX.Objective: To assess what is known about the efficacy and safety of topical methotrexate.Methods: A search on Pubmed was conducted. There were no limits on publication date.Results: A total of 963 articles were discovered. Using our exclusion criteria, 916 articles were excluded; 47 articles were used for full text assessment. Topical MTX has been used primarily in psoriasis but also in mycosis fungoides, lymphomatoid papulosis, and oral precancerous lesions. Optimal delivery system and formulation for adequate penetration is still under investigation.Conclusion: The quality of evidence for the utility of topical methotrexate in psoriasis is good, however, for other dermatologic diseases, the quality is poor. Topical MTX with improved delivery methods may be a viable tool against certain localized dermatologic conditions for patients who do not tolerate oral MTX. Further double-blinded randomized controled studies are needed to substantiate the utility of topical methotrexate.

Rapidly dissolving microneedle patch for synergistic gene and photothermal therapy of subcutaneous tumor

The synergistic combination of gene therapy and photothermal therapy (PTT) has been widely investigated as a promising strategy for cancer treatment. To deliver genes and photothermal agents simultaneously and accurately to a tumor site, a microneedle (MN) patch co-loaded with p53 DNA and IR820 was fabricated by a two-step casting method. Hyaluronic acid was chosen as a matrix and p53 DNA and IR820 were mainly loaded into the tips to enhance utilization and reduce waste. The MN patch could efficiently penetrate the stratum corneum, and dissolve rapidly to release p53 DNA and IR820 in the subcutaneous tumor site. Due to the efficient photothermal efficacy of IR820, the temperature of the tumor site where the MN patch was applied increased by 14.7 °C under near-infrared light irradiation. The MN patch showed excellent antitumor effects in vivo owing to the synergistic effect of gene therapy and PTT. Consequently, the p53 DNA/IR820 MN patch may be a promising synergistic strategy for subcutaneous tumor treatments.

Iontophoretic delivery of methotrexate in the treatment of palmar psoriasis: A randomised controlled study

BACKGROUND/OBJECTIVES

Palmoplantar psoriasis is a localised variant of psoriasis. Topical therapy is the preferred treatment modality, but in severe and recalcitrant cases, systemic drugs like methotrexate are prescribed, with potential for significant adverse effects. Iontophoresis is gaining popularity in enhancing the transdermal delivery of drugs in ionic state. This study was undertaken to evaluate and compare the efficacy of topical methotrexate by iontophoresis technique with clobetasol propionate 0.05% ointment in the treatment of palmar psoriasis.

METHODS

This was a prospective randomised controlled study conducted on patients with palmar psoriasis. Group 1 patients (n = 31) were treated with once weekly iontophoretic delivery of methotrexate over 6 sittings, and group 2 patients (n = 31) were treated with clobetasol propionate 0.05% ointment, twice daily for 6 weeks. Severity of palmar psoriasis was assessed by modified Palmoplantar Pustular Psoriasis Area and Severity Index (m-PPPASI), and treatment was considered as satisfactory when there was >50% improvement.

RESULTS

Sixty two patients were recruited, of which 50 completed the study. Eight out of 25 (32%) patients in group 1 and 12 out of 25 (48%) patients in group 2 showed satisfactory improvement at the end of 6 weeks. However, this difference was statistically not significant (P = 0.25). Burn injury was noted in 12 (48%) group 1 patients with no adverse effects in group 2.

CONCLUSION

Iontophoretic delivery of methotrexate is a promising therapeutic modality, the efficacy of which is comparable to that of clobetasol propionate ointment in the treatment of palmar psoriasis.

Hyaluronic Acid-Based Dissolving Microneedle Patch Loaded with Methotrexate for Improved Treatment of Psoriasis

Methotrexate (MTX) is one of the first-line treatments for moderate to severe psoriasis, while the side effects caused by injection and oral administration of MTX greatly restrict its clinical application. Transdermal drug delivery offers a desirable alternative to the conventional approaches, but the performances of the currently available skin penetration enhancement techniques are not so satisfactory. To address these limitations, we developed a dissolving microneedle (MN) patch made of hyaluronic acid (HA) with excellent water solubility, biocompatibility, biodegradability, and mechanical properties. The amount of MTX encapsulated in the needles of the patch could be controlled during the fabrication process for precise dosage. Interestingly, the MTX-loaded MNs successfully penetrated imiquimod (IMQ)-induced thickened epidermis in mice and delivered the drug intralesionally. Meanwhile, fast dissolution of HA endowed the MNs with operability for patients. We found that the MTX-loaded MNs not only showed well-maintained inhibitory effect in vitro but also alleviated the psoriasis-like skin inflammation in mice. Moreover, the MTX-loaded MNs were significantly more efficacious than taking the same dose of drug orally. Consequently, a higher oral dose of MTX was required for a comparable amelioration, which in turn increased its systemic toxicity. Taken together, the proposed MTX-loaded dissolving MN patch strategy provides a new opportunity for efficient and safe treatment of psoriasis.

Delivery of Methotrexate and Characterization of Skin Treated by Fabricated PLGA Microneedles and Fractional Ablative Laser

PURPOSE

This study investigated in vitro transdermal delivery of methotrexate through dermatomed porcine ear and cadaver human skin treated with poly (D,L-lactide-co-glycolide) acid microneedles or fractional ablative laser.

METHODS

PLGA microneedles were fabricated and characterized using scanning electron microscopy and mechanical assessment techniques. The integrity of treated skin was evaluated by rheometer, transepidermal water loss, and skin electrical resistance measurements. Successful skin microporation was demonstrated by dye binding, histology, pore uniformity, confocal laser microscopy, and DermaScan studies. In vitro permeation experiment was performed on Franz diffusion cells to determine drug delivery into and across the skin.

RESULTS

Both physical treatments resulted in a considerable decrease in skin resistance and an increase in transepidermal water loss value. The laser-created microchannels were significantly larger than those formed by microneedles (p < 0.05). An effective force of 41.04 ± 18.33 N was required to achieve 100% penetration efficiency of the microneedles. For both porcine ear and human skin, laser ablation provided a significantly higher methotrexate permeability into the receptor chamber and skin layers compared to microneedle poration and untreated skin (p < 0.05).

CONCLUSIONS

Both fractional ablative laser and polymeric microneedles markedly enhanced in vitro transdermal delivery of methotrexate into and across skin. Graphical Abstract ᅟ.

Novel methotrexate soft nanocarrier/fractional erbium YAG laser combination for clinical treatment of plaque psoriasis

Psoriasis is a commonly encountered chronic dermatological disease, presenting with inflammatory symptoms in patients. Systemic treatment of psoriasis is associated with several adverse effects, therefore the development of a customized topical treatment modality for psoriasis would be an interesting alternative to systemic delivery. The therapeutic modality explored in this article was the comparative treatment of psoriatic patients using nanoparticulated methotrexate in the form of jojoba oil-based microemulsion with or without fractional erbium YAG laser. Assessment parameters included follow-up photography for up to 8 weeks of treatment, estimation of the psoriasis severity [TES (thickness, erythema, scales)] score, and histopathological skin evaluation. The prepared methotrexate microemulsion was clinically beneficial and safe in treatment of psoriasis vulgaris. The concomitant use of the fractional laser provided improvement in the psoriatic plaques within shorter time duration (3 weeks compared to 8 weeks of treatment), presenting an alternative topical treatment modality for psoriasis vulgaris.

Pharmacokinetic profile of methotrexate in psoriatic skin via the oral or subcutaneous route using dermal microdialysis showing higher methotrexate bioavailability in psoriasis plaques than in non-lesional skin

AIMS

The aim of this pilot study was to use microdialysis to evaluate levels of Methotrexate (MTX) directly in psoriatic skin following oral or subcutaneous administration of MTX to elaborate a complete pharmacokinetic profile within the dermal skin.

METHODS

Six patients with chronic plaque psoriasis on the arm undergoing treatment with MTX were included in a mono-centre clinical trial. Patients were under treatment with p.o. or s.c. MTX (7.5 and 15 mg) for at least 3 months. Interstitial fluid was collected ex vivo via dermal microdialysis from lesional or non-lesional skin and via intravenous microdialysis as well as blood serum every hour up to 10 h after methotrexate administration every hour. MTX was analysed via liquid chromatography.

RESULTS

The area under the curve (AUC) of methotrexate from peripheral blood was up to four times higher than from microdiaylsis, which detection of free unbound MTX. The AUC from dialysates in psoriatic lesional skin was higher than in non-lesional psoriatic skin, and the AUC levels from i.v. microdialysis were non-significantly higher than those from lesional psoriatic skin. Pharmacokinetic profiles were individually quite different and did not primarily depend on the dose or the means (p.o. vs. s.c.) in which it was administered.

CONCLUSION

Dermal microdialysis is a valid tool to evaluate levels of methotrexate in the skin of psoriasis patients. Drug levels and bioavailability of methotrexate were higher in lesional than non-lesional psoriatic skin. The individual AUC of MTX was not primarily dependent on the route or dose of administration.

Physical energy for drug delivery; poration, concentration and activation

Techniques for controlling the rate and duration of drug delivery, while targeting specific locations of the body for treatment, to deliver the cargo (drugs or DNA) to particular parts of the body by what are becoming called "smart drug carriers" have gained increased attention during recent years. Using such smart carriers, researchers have also been investigating a number of physical energy forces including: magnetic fields, ultrasound, electric fields, temperature gradients, photoactivation or photorelease mechanisms, and mechanical forces to enhance drug delivery within the targeted cells or tissues and also to activate the drugs using a similar or a different type of external trigger. This review aims to cover a number of such physical energy modalities. Various advanced techniques such as magnetoporation, electroporation, iontophoresis, sonoporation/mechnoporation, phonophoresis, optoporation and thermoporation will be covered in the review. Special emphasis will be placed on photodynamic therapy owing to the experience of the authors' laboratory in this area, but other types of drug cargo and DNA vectors will also be covered. Photothermal therapy and theranostics will also be discussed.

Engineering approaches to transdermal drug delivery: a tribute to contributions of prof. Robert Langer

Transdermal drug delivery continues to provide an advantageous route of drug administration over injections. While the number of drugs delivered by passive transdermal patches has increased over the years, no macromolecule is currently delivered by the transdermal route. Substantial research efforts have been dedicated by a large number of researchers representing varied disciplines including biology, chemistry, pharmaceutics and engineering to understand, model and overcome the skin's barrier properties. This article focuses on engineering contributions to the field of transdermal drug delivery. The article pays tribute to Prof. Robert Langer, who pioneered the engineering approach towards transdermal drug delivery. Over a period spanning nearly 25 years since his first publication in the field of transdermal drug delivery, Bob Langer has deeply impacted the field by quantitative analysis and innovative engineering. At the same time, he has inspired several generations of engineers by collaborations and mentorship. His scientific insights, innovative technologies, translational efforts and dedicated mentorship have transformed the field.

Transdermal delivery of methotrexate: past, present and future prospects

Methotrexate has been reported as an immunosuppressant and an antimetabolite widely used in the treatment of rheumatoid arthritis and psoriasis. However, it causes various toxicities and has low bioavailability when taken orally, thus, it is desirable that the drug be delivered transdermally. The water solubility and charged structure of methotrexate, however, limits its use via the transdermal route mainly due to the highly organized microstructure of the stratum corneum. Hence, various technologies, such as chemical enhancers, iontophoresis, electroporation, ultrasound and microneedles, either alone or in combination, are being explored to enhance its permeability by disrupting the barrier property of the skin. The present article discusses the past, present and future of transdermal delivery of methotrexate.

Painless skin electroporation as a novel way for insulin delivery

BACKGROUND

Rigorous research efforts have been undertaken worldwide to develop a needle-free insulin delivery for many decades with limited success. This translational study aims to deliver insulin through skin with painless electroporation.

METHODS

A recently designed microelectrode array was used to deliver insulin in mice with diabetes under electroporation conditions that are painless and harmless on human skin.

RESULTS

Under such condition, a therapeutic amount of insulin was delivered successfully through mouse skin. Electroporation alone increased insulin transport around 100-fold compared with passive diffusion. Increased skin temperature to 40°C for 20 min augmented insulin transport to 237-fold more than the control value. Repeated electroporation showed no harm on human skin.

CONCLUSION

The results indicate the potential of painless delivery of insulin through human skin in future clinical practice.

Enhancing percutaneous delivery of methotrexate using different types of surfactants

Regarding the potential severe toxicity associated with systemic administration of methotrexate (MTX), a topical formulation might be of greater utility for the treatment of psoriasis and other hyperproliferative skin disorders. One of the presumed reasons for the lack of clinical activity of topical methotrexate in psoriasis is insufficient percutaneous penetration necessary to inhibit epidermal DNA synthesis. The present study was undertaken to prepare a formulation to enhance skin penetration of MTX. For this mean, topical gel formulations were prepared and evaluated for MTX percutaneous absorption using rat skin and standard Franz diffusion cells. For enhancing percutaneous absorption, three surfactants (anionic, cationic and nonionic) were incorporated into formulations with different concentrations. Finally salicylic acid as a keratolytic material was added for more enhancement effect. The results showed that SLS (sodium lauryl sulphate) and alkyl benzyl dimethyl chloride did not show significant enhancement effect on the penetration of MTX. Transcutol was able to enhance transdermal absorption of MTX and the higher enhancement ratio was obtained with 2% (w/w) concentration of transcutol. Addition of salicylic acid increased this ratio. Prepared formulation containing transcutol 2% (w/w) and salicylic acid 6% (w/w) showed higher enhancement property and could be used clinically for local treatment of psoriasis.

Synergistic effect of iontophoresis and soluble microneedles for transdermal delivery of methotrexate

The aim of this study was to investigate the transdermal iontophoretic delivery of methotrexate, alone or in combination with microneedles, in-vitro and in-vivo using intracutaneous microdialysis in the hairless rat. The average depth of the microdialysis probe in the skin was found to be 0.54 mm. Methotrexate was stable in the presence of an applied electric field as determined by cyclic voltammetry. A current density of 0.4 mA cm−2 applied for 60 min was used in combination with maltose microneedles to enhance delivery of methotrexate across the skin. Delivery was enhanced by iontophoresis and microneedles, both in-vitro and in-vivo. A synergistic 25-fold enhancement of delivery was observed in-vivo when a combination of microneedles and iontophoresis was used compared with either modality alone.

Electroporation as an efficient physical enhancer for skin drug delivery

Transdermal drug delivery offers an attractive alternative to the conventional drug delivery methods of oral administration and injection. However, the stratum corneum acts as a barrier that limits the penetration of substances through the skin. Application of high-voltage pulses to the skin increases its permeability (electroporation) and enables the delivery of various substances into and through the skin. The application of electroporation to the skin has been shown to increase transdermal drug delivery. Moreover, electroporation, used alone or in combination with other enhancement methods, expands the range of drugs (small to macromolecules, lipophilic or hydrophilic, charged or neutral molecules) that can be delivered transdermally. The efficacy of transport depends on the electrical parameters and the physicochemical properties of drugs. The in vivo application of high-voltage pulses is well tolerated, but muscle contractions are usually induced. The electrode and patch design is an important issue to reduce the discomfort of the electrical treatment in humans. This review presents the main findings in the field of electroporation-namely, transdermal drug delivery. Particular attention is paid to proposed enhancement mechanisms and trends in the field of topical and transdermal delivery.

Overview of drug delivery and alternative methods to electroporation

This chapter provides an overview of the application of electroporation to areas other than gene delivery. These areas include the delivery of drugs and vaccines to tissues and tumors as well as into and through the skin. Achievements and limitations of electroporation in these areas are presented. Alternative physical methods for gene and drug delivery besides electroporation are described. The advantages and drawbacks of electroporation, compared with these methods, are also discussed.

Methotrexate delivery to the eye using transscleral hydrogel iontophoresis

PURPOSE

To evaluate methotrexate penetration and distribution profile in ocular structures after short low current transscleral hydrogel iontophoresis.

METHODS

Methotrexate iontophoresis was studied in rabbits using drug-loaded hydrogels mounted on a portable iontophoretic device. Drug distribution profile was evaluated 2, 4, and 8 hours after iontophoretic treatment of 1.6 mA/cm2 for 4 min. Ocular drug levels were also determined two hours after iontophoretic treatment of 5 mA/cm2, compared to mock iontophoresis and intravitreal injection of methotrexate.

RESULTS

Therapeutic drug levels were maintained for at least 8 h at the sclera and retina and for 2 h at the aqueous humor following the iontophoretic treatment. After increasing the current density, a twice-higher concentration was achieved at the vitreous and 8 to 20 time higher concentrations at the retina and sclera.

CONCLUSIONS

A short low current non-invasive iontophoretic treatment using methotrexate-loaded hydrogels has a potential clinical value in treating ocular inflammatory diseases and intraocular lymphoma.

Percutaneous Penetration Enhancers: An Overview

Transdermal drug delivery is the controlled release of drugs through the skin to obtain therapeutic levels systematically. Several technological advances have been made in the recent decades to enhance percutaneous drug penetration. This overview focuses on the physical, biochemical, and chemical means of penetration enhancement, as well as the classification and mechanisms of chemical penetration enhancers, their application in transdermal drug delivery, and trends and development in penetration enhancement.

A geometrical model of dermal capillary clearance

A new microscopic model is developed to describe the dermal capillary clearance process of skin permeants. The physiological structure is represented in terms of a doubly periodic array of absorbing capillaries. Convection-dominated transport in the blood flow within the capillaries is coupled with interstitial diffusion, the latter process being quantified via a slender-body-theory approach. Convection across the capillary wall and in the interstitial phase is treated as a perturbation which may be added to the diffusive transport. The model accounts for the finite permeability of the capillary wall as well as for the geometry of the capillary array, based on realistic values of physiological parameters. Calculated dermal concentration profiles for permeants having the size and lipophilicity of salicylic acid and glucose illustrate the power and general applicability of the model. Furthermore, validation of the model with published in vivo experimental results pertaining to human skin permeation of hydrocortisone is presented. The model offers the possibility for in-depth theoretical understanding and prediction of subsurface drug distribution in the human skin following topical application, as well as rates of capillary clearance into the systemic circulation. A simpler approach that treats the capillary bed as a homogeneously absorbing zone is also employed. The latter may be used in conjunction with the capillary exchange model to estimate measurable dermal transport and clearance parameters in a straightforward manner.