Metered-dose Transdermal Spray Research Articles

Current Updates in Transdermal Therapeutic Systems and Their Role in Neurological Disorders.

The transdermal therapeutic system plays an important role in the treatment of neuropathic pain. Transdermal drug delivery is considered an ideal therapeutic approach for the management of chronic neurological disorders in the elderly population. It is a simple to use, non-invasive and painless drug delivery system, which provides sustained therapeutic plasma levels of drug for an extended period. Moreover, it bypasses the first-pass metabolism of the active agent, improves bioavailability and reduces undesired adverse effects, which in turn improves patient compliance. Several transdermal delivery systems are currently under investigation for the treatment of Parkinson's syndrome, Alzheimer's disorders, and Neurological pain. Drug delivery via the transdermal route is proposed as an alternative remedy to overcome the drawbacks associated with the conventional dosage forms for chronic neurological disorders. The management of Alzheimer's disease via transdermal drug administration exhibits the greatest therapeutic improvements in the treatment of cognition and global functioning among neuropathic patients. Technological breakthroughs in transdermal drug administration such as the microreservior system, microneedles, metered-dose transdermal spray (MDTS), needle-free injections, and ultrasound-based transdermal therapeutic systems have been successfully used to treat neurological disorders. For example, microneedle (MN) is a highly efficient and versatile device due to its distinctive properties. Ultrasounds have been very popular for the delivery of bioactive agents across the skin barrier. This review focuses on the recent advances of various technologies employed in the transdermal therapeutic systems and their applications on neurological disorders for achieving therapeutic outcomes on patients.

The use of estradiol metered-dose transdermal spray in clinical practice

Objective: The aim of this study was to evaluate the use of novel estradiol metered-dose transdermal spray (EMDTS) in the treatment of acute climacteric syndrome.Methods: A multicenter open-label trial was conducted with a 24-week intervention. EMDTS 1.53 mg was given to symptomatic menopausal women. The Menopause Rating Scale (MRS) was used to assess the climacteric syndrome severity. The Friedman non-parametric test and a post-hoc test with Bonferroni correction were used for statistical evaluation.Results: A total of 132 women were enrolled in 20 centers, of whom 123 (93.2%) completed the study. The average age of patients was 53.8 years (37–65 years). The study was discontinued by 6.8% of women. The patients were checked at the beginning of the study, and after 12 and 24 weeks. There was a statistically significant drop (p < 0.001) in MRS values both after 12 and 24 weeks of therapy. The average MRS values improved by 66.2% between the first and the third visits. The most significant improvement was manifested in patients with initial moderate climacteric syndrome (70.9%).Conclusion: This study confirms that application of EMDTS offers a novel treatment option for climacteric symptoms.

Comparison of efficacy and local tolerability of estradiol metered-dose transdermal spray to estradiol patch in a network meta-analysis

Objectives: Transdermal hormone replacement therapy is preferred for menopausal vasomotor symptoms. Our purpose was to compare the efficacy and local tolerability of a patch and a metered-dose transdermal spray that have never been directly compared.Method: The relative change in the number of hot flushes between baseline and week 12 was selected as an efficacy indicator and the frequency of local skin reactions as a tolerability indicator. A network meta-analysis was performed to compare efficacy. Application site tolerability was compared descriptively.Results: Overall 46 studies were identified. In the efficacy analysis, eight active treatment arms and a placebo arm were determined based on the estradiol daily dose (from 14 μg to 50 μg). All but one had a significantly higher effect on relative change in the number of hot flushes than did the placebo. We found no evidence for different efficacy of the patch and the metered-dose transdermal spray. The latter performed better in terms of local skin reactions.Conclusion: The patch and the metered-dose transdermal spray seem to have the same efficacy on vasomotor symptoms in estradiol hormone replacement. The local tolerability of the metered-dose transdermal spray is favorable.

Lopinavir metered-dose transdermal spray through microporated skin: Permeation enhancement to achieve therapeutic needs

A user friendly metered-dose transdermal spray (MDTS) of Lopinavir was developed and a combination of chemical and physical penetration enhancement techniques was utilized to enhance overall drug permeation across skin. Formulation was optimized varying Kollidon® VA 64 level while optimized batch was exhaustively characterized for in vitro drug release, ex vivo skin permeation and in vivo bioavailability. Safety and stability were also ascertained. Formulation containing 5 %w/v of Kollidon® had best sprayability and volatilization property. A significantly high permeation enhancement ratio (1.77) and steady state transdermal flux (52.5 μg/cm2/h) through microporated pig ear skin ex vivo indicated the permeation enhancement potential of the techniques applied. A remarkable 3-fold rise in relative bioavailability via transdermal route (FMDTS via microporated skin = 291.15%) as compared to oral suspension of marketed tablet (AUC0−∞ = 45.94 h*μg/ml) further confirmed the validity of our hypothesis. The outcomes of in vitro, ex vivo and in vivo characterization of Lopinavir MDTS represented the system as safe, effective and stable which seems promising for their extended clinical evaluation.

Transdermal Spray in Hormone Delivery

This review examines advances in hormone delivery, particularly using transdermal spray. Transdermal gels, emulsions, patches, subcutaneous implants and sprays have been developed for transdermal hormone therapy in recent years. Transdermal sprays, in their general form of metered-dose transdermal spray, possess major advantages such as enhanced passive transdermal drug delivery with little or no skin irritations, improved cosmetic acceptability, dose flexibility, uniform distribution on the application site and ease of manufacture, and have thus assumed significant importance in hormone delivery. Estradiol, nestrone, testosterone and hydrocortisone aceponate are some of the drugs prepared as metered-dose transdermal spray. Results from recent surveys indicate that there is a market for the delivery system and ongoing development of transdermal sprays for hormone delivery.

Preparation and the Biopharmaceutical Evaluation for the Metered Dose Transdermal Spray of Dexketoprofen

The objective of the present work was to develop a metered dose transdermal spray (MDTS) formulation for transdermal delivery of dexketoprofen (DE). DE release from a series of formulations was assessed in vitro. Various qualitative and quantitative parameters like spray pattern, pump seal efficiency test, average weight per metered dose, and dose uniformity were evaluated. The optimized formulation with good skin permeation and an appropriate drug concentration and permeation enhancer (PE) content was developed incorporating 7% (w/w, %) DE, 7% (v/v, %) isopropyl myristate (IPM), and 93% (v/v, %) ethanol. In vivo pharmacokinetic study indicated that the optimized formulation showed a more sustainable plasma-concentration profile compared with the Fenli group. The antiinflammatory effect of DE MDTS was evaluated by experiments involving egg-albumin-induced paw edema in rats and xylene-induced ear swelling in mice. Acetic acid-induced abdominal constriction was used to evaluate the anti-nociceptive actions of DE MDTS. Pharmacodynamic studies indicated that the DE MDTS has good anti-inflammatory and anti-nociceptive activities. Besides, skin irritation studies were performed using rat as an animal model. The results obtained show that the MDTS can be a promising and innovative therapeutic system used in transdermal drug delivery for DE.

Preparation and characterization of a metered dose transdermal spray for testosterone

The objective of the present work was to develop a metered dose transdermal spray (MDTS) formulation for transdermal delivery of testosterone and to characterize its efficacy. Testosterone release from a series of formulations was assessed in vitro. Skin from hairless mice was used in permeation experiments with Franz diffusion cells. The spray pattern, pump seal efficiency, average weight per metered dose and dose uniformity were evaluated. An optimized formulation containing 10% (w/v) testosterone, 9% (v/v) azone and 91% (v/v) ethanol was based on good skin permeation and acceptable drug concentration and permeation enhancer (PE) content. A skin irritation study indicated that the formulation was non-irritating in a rat model. An in vivo pharmacokinetic study indicated that the optimized formulation showed a different plasma concentration-time profile from that of the commercially available product Testopatch®. The Testopatch® product demonstrated a more sustainable drug release. The evaluation of the testosterone MDTS indicated that it could deliver reproducible amounts of the formulation per actuation. The results obtained showed that the MDTS is a potential alternative therapeutic system for transdermal testosterone delivery.

Steady‐State Pharmacokinetics Following Application of a Novel Transdermal Estradiol Spray in Healthy Postmenopausal Women

This study was designed to evaluate the steady-state pharmacokinetics (PK) of estradiol and its metabolites, estrone and estrone sulfate, following application of a novel estradiol transdermal spray to healthy postmenopausal women. Participants were randomly assigned in parallel to receive 1-, 2-, or 3-spray doses (24 participants/dose level) of a 1.7% estradiol metered-dose transdermal spray (1.53 mg/spray) once daily for 14 days. Blood was collected predose on days 1 to 14 and over 7 days after the last dose. Serum concentrations for all 3 analytes reached steady state by day 7 or 8 and were still slightly above baseline on day 21. Estradiol, estrone, and estrone sulfate serum concentrations generally increased with increasing dose. Mean estradiol and estrone maximum serum concentration (C(max)) following 1, 2, or 3 sprays for 14 days were 36 and 50, 57 and 60, and 54 and 71 pg/mL, respectively. Estradiol time when maximum concentration occurred (t(max)) was 18 to 20 hours. The area under the serum concentration-time curve over 24 hours following the last dose of study drug (AUC(0-24 h)) on day 14 for the 1-, 2-, and 3-spray groups, respectively, was 471, 736, and 742 pg.h/mL for estradiol; 886, 1208, and 1367 pg x h/mL for estrone; and 16,501, 26,515, and 27,971 pg x h/mL for estrone sulfate. The metered-dose estradiol transdermal spray delivers estradiol at therapeutic levels and produces low serum estrone concentrations.

The effects of skin-to-skin contact, application site washing, and sunscreen use on the pharmacokinetics of estradiol from a metered-dose transdermal spray

This study evaluated the transfer of estradiol by skin-to-skin contact and the influence of washing and sunscreen use on the absorption of estradiol from a transdermal spray. Studies were conducted in the same group of 20 healthy postmenopausal women over a period of 18 days. The women were dosed with three sprays of study medication once daily (a total daily dose of 4.59 mg). To evaluate skin-to-skin transfer, estradiol levels in 20 untreated men were evaluated before and after direct skin-to-skin contact with the application sites of 20 treated women after application of study medication on study days 1 to 3. To examine the effect of washing the application site, estradiol absorption was evaluated when the application site was washed 1 hour after application compared with the unwashed site on study days 10 to 12. To examine the effects of sunscreen use, estradiol pharmacokinetic profiles were evaluated when sunscreen was applied before and after study drug application on study days 14 to 17. The 90% CI of the ratios of the areas under the serum estradiol-time curves (AUC0-24) in untreated men before and after contact with treated women was 1.00 to 1.07, which was within the prespecified equivalence range (0.8-1.25). The 90% CI of the AUC0-24 ratios with and without application site washing was 0.92 to 1.15. Application of sunscreen 1 hour after study drug resulted in a 90% CI of AUC0-24 ratios of 0.76 to 1.08. Application of sunscreen 1 hour before study drug resulted in a 90% CI of AUC0-24 ratios of 0.86 to 1.23. The use of a transdermal estradiol spray did not result in a significant transfer of estradiol by skin-to-skin contact. Washing the application site did not significantly affect absorption of estradiol. Estradiol absorption was slightly decreased due to the application of sunscreen after study drug application, but was unaffected when sunscreen was applied before study drug.

Safety and Efficacy of a Testosterone Metered-Dose Transdermal Spray for Treating Decreased Sexual Satisfaction in Premenopausal Women

It is not known whether premenopausal women who report low sexual satisfaction and have low circulating testosterone levels will benefit from testosterone therapy. To evaluate the effects of exogenous testosterone in premenopausal women reporting diminished sexual function. Randomized, double-blind, placebo-controlled, dose-ranging trial. 6 Australian medical centers. 261 women age 35 to 46 years who reported a decrease in satisfying sexual activity relative to their younger years and had a morning serum free testosterone level less than 3.8 pmol/L (<1.1 pg/mL). 3 different doses of testosterone administered by a metered-dose transdermal spray for 16 weeks or placebo. The primary outcome was the mean number of self-reported satisfactory sexual events (SSEs) over 28 days at week 16. The frequency of SSEs, total number of sexual events (every 4 weeks), scores from the modified Sabbatsberg Sexual Self-Rating Scale and the Psychological General Well-Being Index, and safety variables were also measured. The number of SSEs increased during the treatment period in the active treatment groups and the placebo group. The mean number of SSEs over 28 days at week 16 was statistically significantly greater for women treated with the intermediate dose of testosterone therapy (one 90-microL spray) than for women treated with placebo. The least-squares mean was 2.48 versus 1.70 SSEs, respectively (event rate ratio, 1.49 [95% CI, 1.01 to 2.18]; P = 0.04). The frequency of SSEs in women treated with low and high doses of testosterone did not differ from that in women who took placebo. The rate ratios based on the least-squares mean rates of SSEs during weeks 4 to 16 for each treatment group showed statistically significant or borderline significant increases in all testosterone groups compared with the placebo group. The rate ratios for the one 56-microL spray, one 90-microL spray, and two 90-microL sprays treatment groups were 1.34 (CI, 0.97 to 1.85; P = 0.081), 1.48 (CI, 1.07 to 2.06; P = 0.018), and 1.38 (CI, 1.00 to 1.92; P = 0.052), respectively. At week 16, 95% of women treated with the one 90-microL dose had a free testosterone level less than the upper limit of the reference range for women. The most frequently reported adverse event was hypertrichosis, which was dose-related and mostly confined to the application site. No clinically relevant changes in blood test values, serum biochemical variables, or vital signs occurred. The study duration was short, and the placebo effect was strong. A daily 90-microL dose of transdermal testosterone improves self-reported sexual satisfaction for premenopausal women with reduced libido and low serum-free testosterone levels by a mean of 0.8 SSE per month. The rate of SSEs with higher and lower testosterone doses did not differ from that with placebo.

Transdermal Contraceptive Patches

Many contraceptive methods have been developed for fertility regulation, either reversible or irreversible, in males and females. Oral contraceptives have been considered the most popular form of reversible contraception. However, they must be taken consistently, on a daily basis for 21 or 28 days of each menstrual cycle, in order to achieve the maximal outcomes of contraception. Moreover, their contraceptive efficacy has been reportedly affected by their interactions with many drug products taken concurrently for other conditions. To resolve the dilemma of daily compliance and the risk of potential interactions with drugs taken orally, several non-traditional delivery systems have been developed to permit contraceptive agents and their combinations to be administered via a non-oral route, and also at a lesser frequency of administration, so as to enhance treatment compliance, maximize therapeutic outcomes, and minimize adverse effects. One typical example is the successful development of the ethinylestradiol/norelgestromin patch for achieving contraception in females via transdermal delivery. With topical application on intact skin, each patch delivers a combination of norelgestromin and ethinylestradiol for a week. With a treatment schedule of 3 weeks with a patch on and 1 week without a patch for each menstrual cycle, the ethinylestradiol/norelgestromin patch has achieved a clinical efficacy that is considered bioequivalent to oral contraceptives (with an unintended pregnancy rate of 0.8% per woman-year for the patch versus 0.1% per woman-year for the combined oral contraceptive).Stimulated by the marketing success of the ethinylestradiol/norelgestromin transdermal contraceptive patch, and a growing recognition of the therapeutic benefits realized by delivering an orally inactive progestin via a transdermal route, other transdermal drug delivery systems (DDS), such as transdermal gels and a metered-dose transdermal spray system, have also been developed. Further transdermal contraceptive patches have also been developed. One of these is similar to the ethinylestradiol/norelgestromin patch, in that it is fabricated from an adhesive polymer matrix diffusion-controlled DDS; however, it has a two times smaller patch size (to minimize localized reactions at the application site). This was made possible by substituting norelgestromin with a more potent progestin called gestodene, that has a higher skin permeation rate. The other transdermal patch that has been developed employs a microreservoir partition-controlled delivery system, to provide dual-controlled delivery of estradiol (a natural estrogen) and levonorgestrel (another potent synthetic progestin) at constant rates (zero-order kinetics). Clinical studies have demonstrated that these two new patch systems may be attractive alternative forms of contraception, since ovulation inhibition has been achieved in all subjects who wear the transdermal patch for 3 weeks, replacing it on a weekly basis.A transdermal gel has been formulated to contain elcometrine, which has a progestational potency that is 100 times that of progesterone but is orally inactive, in an alcoholic solution. Preliminary clinical studies have indicated that suppression of ovulation was achieved in the majority of subjects receiving daily application of the transdermal gel. To address the problems associated with the dosing accuracy of the transdermal gel, due to difficulty controlling the area and size of the application site, the feasibility of delivering the transdermal gel from a metered-dose transdermal spray system is currently under evaluation by the Population Council.