OESCLIM: an advanced delivery system for HRT

Transdermal hormone therapy: gels and patches

Hormone therapy (HT) in the climacteric has a number of beneficial effects including mitigation of climacteric symptoms and prevention of osteoporosis. Administration of HT via the transdermal route avoids hepatic first-pass metabolism and therefore the high plasma levels of estrogen metabolites that are associated with oral administration. Patch formulations have traditionally been the most common form of transdermal HT. However, as patches may be associated with local skin reactions, gel formulations have been developed in an attempt to improve acceptability and compliance with transdermal HT. Patch and gel formulations are equally as effective in treating climacteric symptoms and improving bone mineral density, and the effects are comparable to those achieved by oral HT.

Transdermal hormonal contraception: benefits and risks

Transdermal drug delivery systems have been available in the United States for >20 years. Since the introduction of the first transdermal patch (scopolamine) for the treatment of motion sickness, >35 transdermal patch products have been approved by the US Food and Drug Administration for a variety of indications that include hormone replacement therapy, nicotine replacement therapy, chronic pain (fentanyl), angina (nitroglycerin), hypertension (clonidine), and more recently, overactive bladder (oxybutynin), and contraception (ethinyl estradiol/norelgestromin). Clinical data demonstrated the efficacy and safety of the contraceptive patch; however, concerns regarding estrogen levels and reports of venous thromboembolism led to the development of 2 epidemiologic studies and, subsequently, revised product labeling. Despite this, the contraceptive patch may be an appropriate option for some patients.

Adhesive backing foil interactions affecting the elasticity, adhesion strength of laminates, and how to interpret these properties of branded transdermal patches

Standard tensile strength and peel adhesion tests were carried out to investigate interactions of pressure-sensitive adhesives (PSAs) with several backing foils used for transdermal patches. Seven branded transdermal patches (Alora, Cutanum, Estraderm MX 50, Estraderm TTS 50, Fem7 -50 micrograms, Menorest, Oesclim) were included in the investigation. Their skin adhesion measured in several clinical trials was compared with the results of the laboratory measurements according to PSTC-1 (Peel Adhesion for Single Coated Tapes 180 degrees Angle, Pressure Sensitive Tape Council, Illinois, 1996), such as Young's modulus at 3% elongation and peel adhesion to stainless steel. Data obtained for the PSA-coated backings (laminates) show increasing elasticity with increasing PSA thickness. Interactions of PSAs with backing foil became evident in significant changes in Young's modulus by low PSA thickness, as seen for the silicone adhesive. The Young's moduli of the laminates were found to be influenced not only by the elasticity of the backing foil but also by the chemical structure of the PSA. There was no correlation between the elasticity and peel adhesion of both the laminates and the branded patches. Likewise, for the branded patches the peel adhesion to stainless steel does not correlate with skin adhesion values obtained from clinical trials. The Young's modulus of the branded patches was between 4 N/mm2 (Oesclim) and 501 N/mm2 (Fem7). For the branded transdermal patches no correlation was found between Young's modulus and both the peel force on stainless steel and the skin adhesion reported in studies.

Integrated summary of Ortho Evra/Evra contraceptive patch adhesion in varied climates and conditions

OBJECTIVE

To assess the adhesive reliability of the contraceptive patch (Ortho Evra/Evra).

DESIGN

Pooled data of 3,319 women from three contraceptive studies of up to 13 treatment cycles; a subset of 325 women of the pooled data from warm and humid climates; and 30 women from a three-period, crossover exercise study.

SETTING

184 centers.

PATIENT(S)

3,349 healthy women.

INTERVENTION(S)

In the contraceptive studies, each treatment cycle consisted of three consecutive 7-day patches (21 days) followed by one patch-free week. During each treatment period in the exercise study, women wore the patch for 7 days and participated in one of six activities (normal activity, excluding bathing; sauna; whirlpool; treadmill; cool-water immersion; or a combination of activities) each day at a supervised health center.

MAIN OUTCOME MEASURE(S)

Patch adhesion.

RESULT(S)

In the contraceptive studies, 4.7% of patches were replaced because they fell off (1.8% [1,297 of 70,552 patches]) or became partly detached (2.9% [2,050 of 70,552 patches]); patch replacement rates in centers from a warm, humid climate were 1.7% (85 of 4,877 patches) and 2.6% (128 of 4,877 patches), respectively. Only one of 87 patches (1.1%) completely detached in the exercise study.

CONCLUSION(S)

The reliability of adhesion of the contraceptive patch is excellent and consistent across all studies; only 1.8% and 2.9% of patches required replacement due to complete or partial detachment, respectively. Heat, humidity, and exercise do not affect adhesion.

A comparative and pooled analysis of the safety and tolerability of the contraceptive patch (Ortho Evra/Evra)

OBJECTIVE

To review the safety and tolerability of the contraceptive patch (Ortho Evra/Evra) versus a standard oral contraceptive (Triphasil) and to present the pooled safety and tolerability of the patch across three pivotal studies.

DESIGN

Three open-label, contraceptive studies of up to 13 treatment cycles.

SETTING

183 centers.

PATIENT(S)

Comparative study (812 patch, 605 oral contraceptive); pooled analysis (3,330 patch).

INTERVENTION(S)

The patch regimen was three consecutive 7-day patches (21 days) followed by 1 patch-free week per cycle; the oral contraceptive was dosed according to the U.S. physician package insert.

MAIN OUTCOME MEASURE(S)

Adverse events, laboratory tests, vital signs, and body weight.

RESULT(S)

The incidence of most events was similar between the patch and oral contraceptive groups, with the exception of a higher incidence of application site reactions, breast discomfort (cycles 1 and 2 only), and dysmenorrhea in the patch group. Pooled analysis demonstrated that most application site reactions (92%) and breast symptoms (86%) were mild or moderate in severity, and <2% of participants discontinued the patch because of either event. Only 7 (0.2%) participants experienced a serious adverse event classified as possibly, probably, or likely related to the patch. The mean change in body weight from baseline to the end of treatment was an increase of 0.3 kg.

CONCLUSION(S)

Overall, the contraceptive patch is well tolerated and has a side effect profile similar to an established oral contraceptive.

OESCLIM: pre-clinical and clinical profile

INTRODUCTION

The majority of women will suffer some form of vasomotor symptoms at the menopause. Hormone replacement therapy (HRT) has been shown to reduce the incidence of these symptoms although compliance with HRT is still poor. OESCLIM is a transdermal estrogen-replacement therapy for the treatment of estrogen deficiency.

METHODS

In this paper, the main pre-clinical and clinical data relating to OESCLIM are reviewed.

RESULTS

OESCLIM has a stable pharmacokinetic profile over the treatment period of 3-4 days and has been shown to have advanced pharmacokinetics when compared to other leading transdermal systems. It has been shown to reduce vasomotor symptoms by 94% in post-menopausal women, with near maximal reduction in symptoms after 4 weeks of treatment. In highly symptomatic women, low dose (25 microg/day) OESCLIM therapy resulted in a statistically significant reduction in symptoms compared to placebo from week 3. OESCLIM also has good local skin tolerability, and is significantly better tolerated than Estraderm TTS 50. It is also well accepted among patients. In long-term studies, 79.8% of patients wished to continue OESCLIM therapy at the end of a 3-year study.

CONCLUSION

OESCLIM is an innovative first-line transdermal estrogen-replacement therapy with good efficacy and tolerability. The ability to initiate treatment at a low dose (25 microg/day) may have advantages for the patient starting therapy by reducing symptoms of hyperestrogenism whilst allowing for dose titration upwards if necessary.

The long-term tolerability and efficacy of OESCLIM: results of a 1-year study

OBJECTIVES

A 1-year, open-label, non-comparative study evaluated the long-term tolerability and acceptability of a new generation matrix patch in post menopausal women with estrogen deficiency.

METHODS

Menopausal women (224) from 37 centres in five European countries received OESCLIM 50 microg/d (17-beta estradiol) for 3 months, titrated if necessary to either 25 or 100 microg/d for a further 9 months. Patients received either a continuous or discontinuous estradiol regimen with concomitant sequential progestogen (except hysterectomised patients). Skin tolerability was assessed by patient diaries and questionnaires. Global tolerability, efficacy, laboratory parameters and global acceptability were also monitored.

RESULTS

Almost two-thirds of women did not experience any kind of skin reaction and only 4.3% of all applications (752/17,702) caused site reactions. Of these, the majority caused only slight or no discomfort (63.2%). Only 0.37% of total applications required patch removal; none required therapy. A low percentage of patients withdrew due to tolerability issues: 2.7% due to skin reactions; 7.5% due to hyperestrogenism. The mean number of hot flushes experienced by symptomatic women reduced by 91% from 4.0 at baseline to 0.4 after 2 months. Total cholesterol reduced by 3.9% and LDL cholesterol by 5.1%, with no increase in triglyceride levels. Investigators assessed treatment as effective in 96.8% of cases; well tolerated locally in 93.1% and well tolerated generally in 89.5%. At the end of this 1 year study, 79% of patients wished to continue therapy.

CONCLUSION

OESCLIM is well tolerated locally and systemically in long-term therapy with a high proportion of patients wishing to continue therapy after 1 year.