Research Studies

Clinical & Biochemical Study: Efficacy of #95-08006 Cream on Striae^®, in vivo

Institution: West Coast Dermatologicals

Site of Study: Manhattan Beach, CA

Type of Study: Expert evaluations, patient evaluations, characteristic criteria measurements, instrument measurements

Study #: #95-08006

Study Date: 1994-1995

Study Report Date: June 4, 1995

Study Purpose: Clinical and scientific study to assess the improvement on Striae^® with details on the characteristics and histologolic changes consistent with the improvement

ABSTRACT
Stretch marks have been considered untreatable and a cosmetic problem. This article reviews the efficacy of Striae^® Stretch Mark Crème with Regenetrol Complex^®. Striae^® Stretch Mark Crème with Regenetrol Complex^® was studied in a two month double-blind, controlled study of 40 patients with stretch marks. The product was applied to one area of stretch marks while a control cream was applied to another area comparable to the test area. The results demonstrate that over 70% of patients had a positive benefit from the crème. 40% of the patients had marked clearing. Results could be seen from 2 to 6 weeks. Positive benefits included a reduction in the appearance of the ridges, redness, and whiteness of stretch marks. Older and thicker stretch marks also demonstrated improvement with the application of Striae^® Stretch Mark Crème containing Regenetrol Complex^®.

INTRODUCTION
Stretch marks are a common problem that affects many men and women. Clinically, stretch marks are characterized by a thinning of the skin in streaks located around the hips, thighs, buttocks, abdomen, and shoulders. These streaks are often erythematous, hypo pigmented, and ridged. Lesions occur commonly in the presence of skin “stretching” and elevated hormonal levels. The most classic causes or associations are during: 1) third trimester pregnancy, 2) rapid pubertal growth spurts, 3) rapid weight changes, 4) active weight training, and 5) excessive use of topical cortisones. Histopathologically, there is a marked thinning of all the skin layers with a notable thinning and diminution of collagen fibers and other connective tissue. On electron microscopy, there is a breakdown and friable deterioration of the fibers. Fibroblasts have decreased amounts of endoplasmic reticulum and mitochondria which characterizes a decreased protein synthetic activity.

Several articles discuss the use of different products, including retinoids, but a clearly effective treatment has not been found (1). The purpose of the study reviewed by this article is to investigate the use of a new compound, Regenetrol Complex^®, for the treatment of stretch marks.

METHODS AND MATERIALS
Healthy normal volunteers were recruited in several dermatological clinic centers for the studies. 40 patients were gathered with significant stretch marks on the hips, abdomen and thighs. The average age of the patients was 37 years of age with a range of 16 years to 47 years of age. Of the 40 patients, 29 had positive history of the stretch marks occurring during or immediately after pregnancy. 7 patients had lesions from pubertal growth periods, and 4 had lesions from weight training.

Patients were instructed to apply Striae^® Stretch Mark Crème with Regenetrol Complex^® to the stretch marks twice a day. Application was done by rubbing a generous amount thoroughly into the skin. A control cream was applied to one side of the body, and Striae^® Stretch Mark Crème with Regenetrol Complex^® was applied to the other side. Neither the evaluators nor the patients knew which cream was used on which side of the body.

The study was performed for 6 weeks with evaluations of the stretch marks before use of the product and 6 weeks afterward. The evaluations were separated into different categories. First, the stretch marks were evaluated for specific characteristics. The lesions were examined for the amount of erythema, hypopigmentation, hyperpigmentation, and ridging. The patients were also evaluated for extent of improvement over the 6 week time period. The evaluation was rated by 0-- no change, 1--mild change, 2--moderate change, and 3--marked change.

As a separate portion of the study, a blinded evaluator examined the skin and was asked to choose the side that had improved based on the initial evaluations. The evaluator’s chosen side was then compared to the actual treatment side versus the control side.

RESULTS
The study evaluated the consequences of applying Striae^® Stretch Mark Crème with Regenetrol Complex^® to the stretch marks on each patient. Table I shows that the majority of the patients (80%) had some measurable improvement in their stretch marks. Out of the 40 patients studied, 45% had mild improvement, 25% had moderate improvement, and 10% had marked improvement. Table II, reflects improvement in the specific characteristics of stretch marks. The erythema and hypo pigmentation improved most dramatically with a 72% response. The hyper pigmentation improved at 56% and the ridging had 40% improvement. Table III shows that the blinded evaluator was able to choose the correct treated, active cream side on 95% of the patients.
[Tables]
CONCLUSION
The study demonstrated the efficacy of Striae^® Stretch Mark Crème with Regenetrol Complex^®. 80% of the patients demonstrated an improvement in the appearance of their stretch marks. Although many of the patients had mild to moderate effects, the results showed promise because of the short duration of treatment (6 weeks). A number of patients had measurable improvement in 2-4 weeks, and, in addition, many of the patients showed progressive, dramatic improvement with additional weeks of treatment.

The improvement in all of the stretch marks' characteristics from Table II is very promising for Regenetrol Complex^®. This conclusively points to a specific action on stretch marks that can improve all facets of the lesions. In a short 6 week study, dramatic improvement in the lesions' erythema and hypo pigmentation would be expected. The ridging effect would correlate with the deepest histologic effect and would continue to improve with continued therapy. However, in 6 weeks, it would not be expected to be the most consistent response. The blinded evaluator response was performed to ensure the quality of the products and ensure that the control cream was not giving a similar response to the active cream. Clearly, there is a visual difference that can be examined with the clinical improvement that Regenetrol Complex^® has on the skin.

Previous studies have initially shown promise using topical retinoids for stretch marks. However, a recent study, also demonstrated that tretinoin 0.025% cream was "ineffective in improving striae distensae in these subjects." Another study pointed out that the effective tretinoin results seen in some studies were flawed because of a possible irritant effect. In smaller studies, other products have been reported to improve stretch marks. Centella asiatica may be effective, but it is a weak sensitizer. Therefore, it may also be working based on an irritant effect.

Striae^® Stretch Mark Crème with Regenetrol Complex^® appears to elevate the level of total protein synthesis. Preliminary laboratory studies have shown an elevated total protein synthesis with a correlative increase in collagen and elastin. As we demonstrated, the histologic thickness of epidermis and dermis was markedly increased as well. The increase in total protein elevation may explain the advantage Regenetrol Complex^® has over other products tested at this time. As seen from a number of studies, all protein fibers, including keratin, collagen, and elastin, were markedly decreased. Therefore, Regenetrol Complex^® may give the most positive structural support in terms of reversing the weakening of skin associated with stretch marks.

Although the study did not examine the most responsive patient for Regenetrol treatment, anecdotal experience has shown that stretch marks that are older and newer both respond well; however, the newer stretch mark lesions appear to be more responsive. Additionally, stretch marks from pregnancy and weight training appeared to equally respond to the product. Responses to growth spurts were positive, but efficacy was a little less. Anatomical areas did not appear to affect the effectiveness of the product.

In conclusion, Striae^® Stretch Mark Crème with Regenetrol Complex^® is the first known product ever studied that has definitely improved the appearance of stretch marks in a short, double-blinded clinical study with specific improvement in the basic clinical characteristics of the stretch marks.