Topical 5-aminolevulinic Acid Research Articles

Ionic Liquid Pretreatment Enhances Skin Penetration of 5-Aminolevulinic Acid: A Promising Scheme for Photodynamic Therapy for Acne Vulgaris.

Acne vulgaris is one of the most prevalent skin disorders; it affects up to 85% of adolescents and often persists into adulthood. Topical 5-aminolevulinic acid (ALA)-based photodynamic therapy (PDT) provides an alternative treatment for acne; however, its efficacy is greatly undermined by the limited skin permeability of ALA. Herein, biocompatible ionic liquids (ILs) based on aliphatic acid/choline were employed to enhance the dermal delivery of ALA, thereby improving the efficacy of PDT. In addition to the one-step delivery of ALA by utilizing ILs as carriers, a two-step strategy of pretreating the skin with blank ILs, followed by the administration of free ALA, was employed to test the IL-facilitated dermal delivery of ALA in vitro. The cumulative permeation of ALA through the excised rat skin after IL pretreatment was significantly greater than that in the untreated group, the 20% dimethyl sulfoxide (DMSO) penetration enhancer group, and the one-step group. The penetration efficiency was influenced by formulation and treatment factors, including the type of IL, pretreatment duration, water content in the ILs, and concentration of ALA. In rats, IL pretreatment facilitated faster, greater, and deeper ALA-induced protoporphyrin IX (PpIX) accumulation. Moreover, the IL pretreatment regimen significantly improved the efficacy of ALA-based PDT against acne vulgaris in a rat ear model. The model IL choline citrate ([Ch]3[Cit]1) had a moderate effect on the skin barrier. Trans-epidermal water loss could be recovered 1 h after IL treatment, but no irritation to the rat skin was detected after 7 days of consecutive treatment. It was concluded that biocompatible IL pretreatment enhances the penetration of ALA and thus facilitates the transformation of PpIX and improves the efficacy of PDT against acne vulgaris.

Comparative study of topical 5-aminolevulinic acid photodynamic therapy and surgery for recurrent cervical high-grade squamous intraepithelial lesions following surgery

ObjectiveThe study aimed to compare the clinical efficacy and safety of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) and surgery in treating recurrent cervical high-grade squamous intraepithelial lesions (HSIL) after surgery due to precancerous lesions. MethodsA total of 41 patients with recurrent cervical HSIL after surgery for precancerous lesions were studied retrospectively. Patients underwent ALA-PDT or surgery and were followed up at 3, 6, 9 and 12 months and then every six months after that. Clinical data were collected and the efficacy and safety of the two treatment methods were compared. ResultsOf the 41 patients with recurrent cervical HSIL after conization, 15 cases received ALA-PDT and 26 received surgery. At the six-month follow-up, the lesions’ complete remission (CR) rate was 93.33 % in ALA-PDT group and 88.46 % in the surgery group. The human papillomavirus (HPV) clearance rates were 66.67 % and 73.08 %, respectively. No significant differences concerning the lesions’ CR rate and the HPV clearance rate were observed between the two groups (P>0.05). At the twelve-month follow-up, the HPV clearance rates were 80.00 % and 91.67 %. No significant differences concerning the HPV clearance rate were observed between the two groups (P>0.05). In the surgery group, the HPV clearance rate and the lesions’ CR rate were lower in patients over 45 years of age (25.00% vs. 81.82 %, P = 0.031; 50.00% vs. 95.45 %, P = 0.052). During the follow-up, there was no significant difference in the recurrence rate between the two groups (P>0.05). In addition, none of the patients progressed. In women treated with ALA-PDT, there was no vaginal bleeding, and no harmful effects on the cervical organizational structure or functions compared to the surgery group, and two women delivered successfully after ALA-PDT treatment. ConclusionsThe efficacy of ALA-PDT was similar to that of surgery in treating recurrent cervical HSIL following surgery, with fewer side effects.

Comparative study of topical 5-aminolevulinic acid photodynamic therapy and surgery in treating vaginal high-grade squamous intraepithelial lesions following hysterectomy

ObjectiveTo compare the clinical efficacy and safety of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) and surgery in treating vaginal high-grade squamous intraepithelial lesions (HSIL) after hysterectomy due to cervical cancer (CC) or precancerous lesions. MethodsA retrospective study was performed comprising 41 women with histologically confirmed vaginal HSIL after hysterectomy for CC or cervical HSIL. Patients were treated with surgery or ALA-PDT and were followed up at 3, 6 and 12 months and then every six months afterwards. Clinical data were collected and the efficacy and safety of the two groups were analyzed. ResultsOf the 41 patients with vaginal HSIL after hysterectomy, 18 were treated with ALA-PDT and 23 underwent surgery. There was no significant difference in the lesions’ complete remission (CR) rate or the human papillomavirus (HPV) clearance rate between the ALA-PDT group and the surgery group (P > 0.05). In the surgery group, the clearance rate of HPV16/18 was higher than that of other high-risk HPV (HR-HPV) and HPV16/18 combined with other HR-HPV (87.50 % vs. 45.45 % vs. 0.00 %, P = 0.014). No significant difference in the recurrence rate between the two groups was noted (P > 0.05). And none of the patients progressed. In the surgery group, one patient developed significant thickening of the vaginal stump, and one patient had increased vaginal discharge. In women treated with ALA-PDT, there was no vaginal bleeding or harmful effects on the organizational structure or functions compared to the surgery group. ConclusionsThe efficacy of ALA-PDT was comparable to that of surgery in treating vaginal HSIL following hysterectomy due to CC or cervical HSIL, with fewer side effects.

Topical 5-aminolevulinic acid photodynamic therapy for recalcitrant facial flat warts

Photodynamic therapy (PDT) uses light energy to excite a photosensitizing agent, leading to production of reactive oxygen species, which exert cytotoxic effects on targeted cells. PDT has emerged as a promising therapeutic modality for the treatment of flat warts caused by human papillomavirus (HPV) infection, by targeting infected keratinocytes and inactivating nonenveloped viral particles. Some patients with recalcitrant flat warts on the face who have poor response to traditional treatment often seek effective therapy to have the warts removed. In this report, we retrospectively evaluated the efficacy of topical 10% 5-aminolevulinic acid PDT (ALA-PDT) in the treatment of 15 patients with recalcitrant facial flat warts. Patients received treatment once every two weeks for a total of two or three sessions. At 24 weeks after the start of treatment, 86.67% of patients showed complete or excellent response. Further more, the remission rate of 100% lesion clearance was 46.67% (seven patients), and the remission rate of 70–100% lesion clearance was 40.00% (six patients). None of the patients experienced disease recurrence or progression. The adverse reactions were generally well tolerated by the patients and mostly resolved in a few days without special treatment. Our findings showed that topical 10% ALA-PDT is a safe and effective treatment for recalcitrant facial flat warts.

Comparative study of topical 5-aminolevulinic acid photodynamic therapy and surgery for the treatment of vulvar squamous intraepithelial lesion

BackgroundVulvar squamous intraepithelial lesion (SIL) is a precursor lesion of vulvar squamous cell carcinoma. The current clinical treatments for vulvar SIL cause damage to the vulvar structure, chronic pain and psychological distress. Topical 5-aminolevulinic acid photodynamic therapy (ALA-PDT) is a novel, non-invasive therapy for intraepithelial lesions. The objective of this study was to compare the clinical efficacy and safety of ALA-PDT with local surgical resection for vulvar SIL. MethodsA total of 56 patients with vulvar SIL were enrolled in this retrospective study. Among them, 16 patients received local resection and 40 patients received ALA-PDT. HPV genotyping and ThinPrep cytologic test (TCT) were used to evaluate treatment efficacy. In addition, colposcopy-directed biopsy was performed in all patients at 3-month follow-up and in patients with positive high-risk human papillomavirus (HR-HPV) and/or abnormal TCT results during the follow-up. ResultsAt 3-month follow-up and in HSIL group the complete remission (CR) rate of the ALA-PDT group and surgery group was 90.6% (29/32) and 87.5% (14/16) (P = 1.000), respectively. The HPV clearance rate of the ALA-PDT group and surgery group was 45.2% (14/31) and 43.8% (7/16) (P = 0.927), respectively. The average numbers of ALA-PDT treatments were 5.34 for HSIL patients and 4.88 for LSIL patients, respectively. The CR rate of HSIL patients and LSIL patients was 90.6% (29/32) and 75.0% (6/8) (P = 0.550), respectively. The HPV clearance rate of HSIL patients and LSIL patients was 45.2% (14/31) and 37.5% (3/8) (P = 1.000), respectively. The ALA-PDT group showed similar clinical efficacy and milder adverse effects compared with the surgical group. ConclusionALA-PDT showed similar clinical efficacy as surgery in the treatment of vulvar SIL, but with milder adverse effects and maintaining the integrity of the vulvar structure.

Effect of topical 5-aminolevulinic acid photodynamic therapy versus therapy combined with CO2 laser pretreatment for patients with cervical high-grade squamous intraepithelial lesions

ObjectiveTo evaluate the effect of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) combined with CO2 laser pretreatment (Laser+ALA-PDT) on patients with cervical high-grade squamous intraepithelial lesions (HSILs). MethodsA total of 114 patients treated by ALA-PDT or Laser+ALA-PDT at 3 centers were retrospectively reviewed. The effective rate, cure rate of lesions as well as high-risk human papillomavirus (HR-HPV) regression rate and persistent infection rate in the 2 groups were compared according to 3–6 month and 9–12 months follow-ups. The characteristics and risk factors for ineffective cases were evaluated by regression analysis. ResultsAt the 3–6month follow-up, the effective rate was significantly higher in the Laser+ALA-PDT group than in the ALA-PDT group (96.6% vs. 81.3%, p = 0.048). A total of 79.3% of the laser+ALA-PDT patients achieved cure rate compared with 61.3% of the ALA-PDT patients (p = 0.082). In the Laser+ALA-PDT group, the HR-HPV-negative rate was significantly higher (72.4% vs. 50.7%, p = 0.045), while the persistence rate was significantly lower (20.7% vs. 42.7%, p = 0.037). At the 9–12month follow-up, the cure rate was 83% in the ALA-PDT group, 17% lower than that in the Laser+ALA-PDT group (p = 0.055). A total of 20.8% of patients in the ALA-PDT group and 5.3% in the Laser+ALA-PDT group showed persistent HR-HPV infection (p = 0.120). Pretreatment HR-HPV type, multiple infections and treatment modality were relevant factors for PDT outcome. ConclusionsFor patients with cervical HSIL, laser+ALA-PDT shows better efficiency and HPV regression compared with ALA-PDT. HPV16/18 and multi-infection may be risk factors for ineffective treatment with ALA-PDT.

Topical 5-aminolevulinic acid photodynamic therapy with novel approach successfully treated refractory deep male urethral condyloma acuminata: A retrospective case series

To the Editor: Deep male urethral condyloma acuminata (MUCA) remains an intractable problem in clinical practice. Because of the deep anatomical location, topical drug therapy, surgical treatment, or holmium laser are all restricted, with high recurrence rates and potentially severe complications such as urethral stenosis and urethral perforation. Five-aminolevulinic acid photodynamic therapy (ALA-PDT) has demonstrated high efficacy, good safety, and low recurrence in MUCA in previous studies.1,2 However, improper delivery of photosensitizers or inaccurate illumination may affect the treatment outcome of ALA-PDT in deep MUCA.

The effect of local photodynamic therapy with 5-aminolevulinic acid in treating different grades of cervical intraepithelial neoplasia

BackgroundCervical intraepithelial neoplasia (CIN) is a precursor lesion of cervical cancer. Traditional treatments for CIN might have negative effects on cervical anatomical structure and physiological function. Topical 5-aminolevulinic acid photodynamic therapy (5-ALA PDT) is a novel, non-invasive targeted therapy for intraepithelial lesions. This study aims to evaluate and compare the efficacy and safety of 5-ALA PDT for different grades of CIN. MethodsA retrospective study of 183 patients aged 19–50 with histologically confirmed CIN and receiving ALA-PDT was conducted. ALA-PDT was performed with 20% ALA thermosensitive gel and irradiation at a wavelength of 635 nm and density of 80–100 J/cm2. ALA-PDT was conducted every 7–10 days for 4–6 times. Patients were followed up three, six, nine, and twelve months after treatment. The effect was evaluated through HPV genotyping, ThinPrep cytology test (TCT), and colposcopy-directed biopsy. ResultsThe HPV clearance rate was 71.0% (130/183) at the six-month follow-up and 84.5% (147/174) at the 12-month follow-up. The complete lesion remission (CR) rate was 90.2% (165/183). No statistically significant differences concerning the CR rate (P>0.05) or HPV clearance rates (P>0.05) were observed in CIN I, CIN II, and CIN III. In women with CIN III, gland involvement was revealed to be associated with a significantly lower HPV clearance rate (63.16% vs. 92.60%, P= 0.036) at the 12-month follow-up. Our study showed that the atypical vessels seemed to be a risk factor for HPV clearance rate in the CIN II group at six-month follow-up, although the difference was not statistically significant (P= 0.089). During the follow-up, 13 cases had persistent lesions (7.1%), four cases recurred (2.3%), and none of the patients progressed. The study also showed that the efficacy of PDT in the treatment of patients with CIN III involving glands was comparable to that of CKC (P>0.05). ConclusionsALA-PDT is an effective andsafe treatment for CIN, and responseis unaffected by the grade of lesions. However, for patients with atypical vessels and glandular involvement, the effect of PDT seems to be poorer.

Topical 5-aminolevulinic acid photodynamic therapy for cervical high-grade squamous intraepithelial lesions

ObjectiveTo evaluate the efficacy of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in the treatment of high-grade squamous intraepithelial lesions of the cervix (HSIL). MethodsThis retrospective study included 22 female patients with histologically confirmed HSIL and high-risk human papillomavirus (HR-HPV) infections. Patients were treated with ALA-PDT once a week for a total of 6 times. All patients had a follow-up period of 3 months and 6 months. The assessment of effectiveness of ALA-PDT was performed by ThinPrep cytology test (TCT), HPV DNA assay, HPV E6/E7 mRNA examination, colposcopy, biopsy, and immunohistochemistry detection. ResultsThree months after 5-ALA PDT, the histologic disappearance rate was 81.82% (18/22), while the HPV clearance rate was 54.55% (12/22). At the 6 months checkpoint, the HSIL disappearance rate was 90.91% (20/22) and the HPV clearance rate was 86.36% (19/22). Before PDT, 68.18% of patients (15/22) were confirmed with TCT abnormalities, while only one patient (1/22, 4.55%) was abnormal in the TCT test at 6 months checkpoint. All participants were found HPV E6/E7 mRNA positive initially, while the HPV E6/E7 mRNA negative rate was 90.91% (20/22) at 6 months checkpoint. Additionally, we found a significant difference of the expression of CD4+ and CD8+ T cells and HPV E6 and E7 proteins before ALA-PDT and at 3 months follow-up (P < 0.01). No severe side effects were seen. ConclusionsTopical 5-ALA PDT is an effective treatment for cervical HSIL with HR-HPV infection.

The effect of high-risk HPV E6/E7 mRNA on the efficacy of topical photodynamic therapy with 5-aminolevulinic acid for cervical high-grade squamous intraepithelial lesions

BackgroundE6 and E7 high-risk human papillomavirus (HR-HPV) oncoproteins are closely associated with the initiation and progression of cervical cancer (CC) and pre-cancerous lesions. Cervical high-grade squamous intraepithelial lesions (HSIL), as pre-cancerous lesions, have a 5% chance of progressing to invasive cancer. Topical 5-aminolevulinic acid photodynamic therapy (ALA-PDT) is a novel non-invasive targeted therapy for intraepithelial lesions. Herein, we analyzed the effect of HR-HPV E6/E7 mRNA on ALA-PDT for cervical HSIL. MethodsA retrospective analysis of 148 HR-HPV-positive patients diagnosed with cervical HSIL and receiving ALA-PDT was carried out. ALA-PDT was performed with 20% ALA thermosensitive gel, and irradiation at wavelength of 635 nm and density of 80–100 J/cm2 for 20–30 min. The therapeutic instruments of LED and semiconductor laser were applied for cervical lesions and lesions in endocervical canal, respectively. All patients were tested for HPV E6/E7 mRNA before and after PDT, and then followed up at 3, 6, and 12 months after treatment, and every six months thereafter. ResultsAt the 6-month follow up, the complete remission (CR) rate of patients’ lesions was 86.5% (128/148), whereas the total HPV clearance rate was 72.3% (107/148). It was evident that positive E6/E7 mRNA before treatment had a significant effect on HPV clearance rate (66.3% VS 81.4%, P = 0.045) and CR rate (80.9% VS 94.9%, P = 0.015). The E6/E7 mRNA associated with HPV16/18 and HPV16/18 combined with other HR-HPV (HPV16/18 and other HR-HPV) affected HPV clearance (P = 0.035) and lesions CR (P = 0.039), respectively. Moreover, persistently positive E6/E7 mRNA after treatment was closely associated with poor efficacy (HPV clearance rate: P = 0.000, CR rate: P = 0.000). Throughout the follow up period, two cases recurred but none of the patients progressed. ConclusionsThis study has shown that ALA-PDT is an effective, safe, and alternative treatment for cervical HSIL, especially for the patients of childbearing age. However, its efficacy is relatively poor in patients with persistently positive E6/E7 mRNA before and after treatment, who are relatively insensitive to ALA-PDT.

Comparative study of topical 5-aminolevulinic acid photodynamic therapy (5-ALA-PDT) and surgery for the treatment of high-grade vaginal intraepithelial neoplasia

ObjectiveTo compare the clinical efficacy and safety of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) and local surgical excision in the treatment of high-grade vaginal intraepithelial neoplasia (VAIN). MethodsThis was a retrospective study of a single center. Patients with biopsy-proven high-grade VAIN were counseled on the option of excision or ALA-PDT. After treatment patients were followed up at 3, 6 and 12 months and every 6 months afterwards. Clinical data of two groups were analyzed. ResultsSixty patients were treated with ALA-PDT and 40 patients underwent excision surgery. The clinical characteristics of patients in the two groups were similar. The mean ages of patients treated with ALA-PDT and local surgical excision were 41.93+13.08 (18-70) and 43.25+11.64 (22–61) years old, respectively. The treatment times of PDT for patients in the ALA-PDT group were 5.48±1.41 (2-8) times. At 3–6 months after treatment, the overall complete remission (CR) rate was 93.33% (56/60) in PDT group and 82.5% (33/40) in local surgical excision group. In PDT group, a 12- and 24-month follow-up, the total HPV clearance rate was 68.97% and 77.55%, respectively. At 12-month and 2-year follow-up after local surgical excision, the total HPV clearance rate was 60% and 64.52%, respectively. Further analysis showed that the clinical efficacy was comparable between the two treatments. Patients over 45 years old exhibited a lower HPV clearance rate (P<0.05) than those under 45 years old. It was also observed that persistent HPV infection is a major risk factor for persistent disease. Further comparative analyses showed no significant difference in the CR rate and treatment times between VAINII and VAINIII in ALA-PDT group. Moreover, 4 patients (11.36%) developed recurrent lesions during follow-up after ALA-PDT, whereas 3 patients (8.33%) in the local excision group developed recurrent lesions. In addition, there was no significant difference in the recurrent rate between two groups. ConclusionsALA-PDT shows similar efficacy and less side effects compared to local surgical excision.

Efficacy and safety of photodynamic therapy mediatied by 5-aminolevulinic acid for the treatment of vaginal high-grade intraepithelial lesions

BackgroundVaginal high-grade squamous intraepithelial lesion (HSIL) (vaginal intraepithelial neoplasia [VAIN] grade 2–3) is clinically, a precancerous lesion condition with an estimated progression rate of 10%–20%. Therefore, treatment is recommended. Because traditional treatments have limited effects, high expense and complications, here we evaluated the efficacy and safety of topical 5-aminolevulinic acid (ALA)–based photodynamic therapy (PDT). MethodsThis study consisted of 56 female patients diagnosed with vaginal HSIL. A 20% 5-ALA jelly formation was topically applied to the vaginal wall, followed by 635 nm PDT at 7–14 days intervals. Cytology, human papillomavirus (HPV) genotyping, colposcopy, and pathology were assessed after treatment. ResultsAmong the 56 patients in our study, 47 (83.9%) had VAIN 2 and 9 (16.1%) had VAIN 3. 35 patients underwent three courses of PDT treatment, 19 experienced six courses, and two experienced nine courses. The total pathological regression rate was 87.5%, and the HPV clearance rate during the 6-month follow-up was 41.9%. Lesions located in the vaginal stump after hysterectomy seem to be difficult to treat. 9%(4/44) and 23%(7/30) patients had recurrent disease during the 6-month and 1-year follow-up time point. The most common adverse event was increased vaginal discharge, other side effects include abdominal pain, vulvar pruritus, and vaginal bleeding. No severe adverse effect was observed during the treatment. ConclusionPhotodynamic therapy mediatied by 5-aminolevulinic acid is an effective and safe treatment for vaginal HSIL with minimal side effects.

Photobiomodulation and photodynamic therapy applied after electrocauterization for skin healing optimization in rats.

Photobiomodulation-PBM and Photodynamic Therapy-PDT have been used to induce healing. However, the effects of these therapies on skin-lesions induced by electrocautery are unknown, aiming at more favorable clinical and esthetic results. Electrocauterization was done in 78-female Wistar-rats using a system that includes an electrocautery and red-LED. The groups were: No injury, Injury, Injury + ALA (topical 5-aminolevulinic acid application), Injury + LED and Injury + ALA + LED (topical ALA application followed by photoactivation with LED). After 2nd, 7th and 14th days post-injury, immuno-histomorphometric analyses (inflammatory infiltrate, blood vessels, fibroblasts, eschar/epidermal thickness, IL-10 and VEGF) and biochemical assays of MPO (neutrophil), NAG (macrophage), nitrite, DCF (H2 O2 ), carbonyl (membrane's damage), sulfhydryl (membrane's integrity), SOD, GSH, hydroxyproline and re-epithelialization area were performed. The Injury + LED and Injury + ALA + LED groups controlled inflammation and oxidative stress, favoring angiogenesis, fibroblasts proliferation and collagen formation. Therefore, the PBM or PDT was effective in tissue formation with thinner eschar and epidermis, resulting in less scarring after electrocauterization.

The effect of local photodynamic therapy with 5-aminolevulinic acid in the treatment of vaginal intraepithelial lesions with high-risk HPV infection

BackgroundRecent data has shown increased rate of vaginal intraepithelial neoplasia (VAIN) in younger individuals. Traditional VAIN treatments exert adverse effects on the anatomy and functions of the vagina. Topical 5-aminolevulinic acid photodynamic therapy (ALA-PDT) is a novel, non-invasive targeted therapy for intraepithelial lesions. Here, we aimed to investigate the efficacy and safety of ALA-PDT in VAIN with high-risk HPV (HR-HPV) infection. MethodsThis study enrolled a total of 82 HR-HPV-positive women diagnosed with VAIN, who were receiving ALA-PDT. The effect of ALA-PDT was evaluated using HPV genotyping and Thinprep cytologic test (TCT). Besides, colposcopy directed biopsies were performed in all patients at 3-month follow-up, and in patients with positive HR-HPV and/or abnormal TCT results during the follow-up period. ResultsOur data showed that the HPV clearance rate was 53.7% (44/82) at 6-month follow-up and 67.1% (55/82) at 12-month follow-up. Patients with HPV16/18 combined with other HR-HPV (HPV16/18 & other HR-HPV) infection, those with a history of hysterectomy and/or older age were had significantly lower HPV clearance rate. Besides, the lesion complete remission (CR) rate was 90.2% (74/82). These results show that HPV16/18 & other HR-HPV infection was associated with significantly lower CR rates. Throughout the follow-up, 2 cases had persistent lesions (2.4%), 6 cases had partial remission (7.3%), 2 cases recurred (2.7%) but none of the patients had disease progression. ConclusionsTaken together, our data showed that ALA-PDT is an effective, safe, and alternative treatment for VAIN patients with HR-HPV infection. However, the ALA-PDT efficacy was relatively poor in patients with older age, HPV16/18 & other HR-HPV infection and/or those with a history of hysterectomy.

Topical 5-Aminolevulinic Acid Photodynamic Therapy for Cervical High-Grade Squamous Intraepithelial Lesions

Topical 5-Aminolevulinic Acid Photodynamic Therapy for Cervical High-Grade Squamous Intraepithelial Lesions

Clinical Pharmacokinetics and Safety of a 10% Aminolevulinic Acid Hydrochloride Nanoemulsion Gel (BF-200 ALA) in Photodynamic Therapy of Patients Extensively Affected With Actinic Keratosis: Results of 2 Maximal Usage Pharmacokinetic Trials.

The nanoemulsion‐based 10% aminolevulinic acid (ALA) hydrochloride gel BF‐200 ALA optimizes epidermal penetration of its active ingredient and is approved for topical photodynamic therapy (PDT) for the treatment of actinic keratosis in the United States and Europe. To characterize systemic absorption from dermal application during PDT, ALA and its key active metabolite protoporphyrin IX (PpIX) were analyzed in 2 maximal usage pharmacokinetic trials (MUsT) in patients severely affected with actinic keratosis. The primary objective of both MUsTs was to assess baseline‐adjusted plasma concentration–time curves for ALA and PpIX after a single PDT treatment applying either 2 g (1 tube) of BF‐200 ALA on the face (MUsT‐1) or applying 6 g (3 tubes) of BF‐200 ALA on the face/scalp or body periphery (MUsT‐2), to 20 or 60 cm2, respectively. All PDTs were performed using red light at around 635 nm wavelength. Safety and tolerability were documented along with pharmacokinetics. In both MUsTs, ALA plasma concentrations were transiently increased to a maximum concentration at about 2.5 to 3.3 times above endogenous baseline with time to maximum concentration at ≈3 hours after dosing. Plasma levels subsequently returned to baseline within 10 hours after dosing. Overall baseline‐adjusted mean area under the baseline‐adjusted plasma concentration‐time curve from time zero to the last sampling time point at which the concentration was at or above the lower limit of quantification ranged from 142.8 to 146.2, indicating that a similar, minor fraction of topical ALA is systemically absorbed under both dosing regimens. Systemic PpIX exposure after administration of either dose of BF‐200 ALA was equally minimal. Application site skin reactions were treatment area size‐related, albeit transient and consistent with the known safety profile of BF‐200 ALA.

Topical tacalcitol as neoadjuvant for photodynamic therapy of acral actinic keratoses: An intra-patient randomized study.

photodynamic therapy (PDT) with topical 5-aminolevulinic acid (ALA) is a well described and widely practiced treatment for actinic keratoses (AKs) on the head and face. Less is known about its use for AKs on upper extremities, which can be challenging for the dermatologist. The aim of our study was to compare the combination of topical tacalcitol before 5-ALA-PDT vs conventional 5-ALA-PDT for acral AKs in a prospective, randomized, intra-individual clinical study. patients with AKs of both upper extremities underwent keratolytic pretreatment with topical tacalcitol on the back of one hand and/or forearm (right vs left), randomly selected, for fifteen consecutive days before PDT. All patients underwent one session of 5-ALA-PDT. Visual analog scale for pain was assessed immediately after PDT session and any side effects were recorded after 3 days. Efficacy was evaluated with lesion count (LC) prior to treatment (V0) and 90 days (V1) after PDT. twenty-one patients with multiple acral AKs were enrolled and completed the study. At V1, neoadjuvant combination of topical tacalcitol plus PDT was significantly more effective than PDT alone (percentage reduction in total lesion count was 44.4 %. There was no significant difference in VAS pain score between the two treatment modalities. Mild erythema was the only local side effect reported for both treatment regimens (52.4 %, tacalcitol plus PDT vs 42.9 %, PDT alone). neoadjuvant use of topical tacalcitol might be useful to improve PDT efficacy, especially in hard-to-treat AKs on extremities.

Effectiveness of a single treatment of photodynamic therapy using topical administration of 5-aminolevulinic acid on methicillin-resistant Staphylococcus aureus-infected wounds of diabetic mice

Methicillin-resistant Staphylococcus aureus (MRSA) is the most important representative pathogen which causes clinically relevant infections in diabetic ulceration. We report our investigations on the efficacy of antimicrobial photodynamic therapy with topical 5-aminolevulinic acid (ALA-PDT) on diabetic murine infected wound models induced with a MRSA SA325 strain. A solution of 10 % 5-aminolevulinic acid (ALA) was placed into the wounds followed by delivery of 25 J/cm2 (635 nm). The ALA-PDT treated wounds healed earlier as compared to others (P < 0.5). A significant reduction of bacterial counts (2.05 logs) was detected in wounds after ALA-PDT on Day 2 (P < 0.5). Additionally, histological analysis revealed that wounds treated with ALA-PDT exhibited a more complete re-epithelialization, blood micro-vessels, collagen-volume fraction and considerable decrease in inflammatory cells infiltration. Immunohistochemistry assay demonstrated considerable reduction of proinflammatory cytokines interleukin-1β (IL-1β), earlier expression of vascular endothelial growth factor A (VEGF-A), increase of basic fibroblast growth factor (bFGF) and Ki-67 in the ALA-PDT group (P < 0.5). These data imply that the therapeutic effect of ALA-PDT revealed an accelerated diabetic wound closure rate, together with reduced hyperinflammatory response and elevated growth factors.

Topical 5-aminolevulinic acid photodynamic therapy for laryngeal papillomatosistosis treatment.

To explore the therapeutic effect of topical 5-Aminolevulinic Acid photodynamic therapy (ALA-PDT) on laryngeal papillomatosis (LP) treatment. 13 patients with LP underwent topical ALA-PDT after tumor resection (CO2laser or/and microdebrider resection). All patients were irradiated 3-4 times. After ALA-PDT treatment, the laryngoscopic examination was performed every 1-2 months to observe the therapeutic effect. All 13 patients were followed up for more than 1 year. Eleven cases (84.6%) showed no recurrence; two cases (15.4%) had relapses. One child developed III° inspiratory dyspnea caused by laryngeal mucosal edema and need endotracheal intubation again. Four patients had adhesion of the anterior commissure of the vocal cord. The detection rate of HPV infections was 76.9% and two patients had multiple HPV subtype co-infection. The preliminary effect of topical ALA-PDT significantly reduces recurrence and improves the cure rate of LP. Further research on this treatment is still required.

Ocular preservation through limited tumor excision combined with ALA-PDT in patients with periocular basal cell carcinoma.

In recent years, photodynamic therapy (PDT) has emerged as a successful technique for treating early non-melanoma skin cancers compared with traditional methods such as surgical operation, chemotherapy, radiotherapy, and immunity treatment, etc. PDT offers excellent aesthetic results and skin function preservation effects, especially so for tumor in difficult-to-treat areas. The purpose of this article was to study the anti-tumor effect of ALA-PDT combined with limited excision in periocular basal cell carcinoma (BCC) and its role in improving the effect of the operation. In our study, 8 patients with periocular basal cell carcinoma were treated with topical aminolevulinic acid photodynamic therapy (ALA-PDT) combined with surgery. After removal of tumor mainly with normal tissue saved, each tumor region was irradiated with 177 J/cm2 using a 635-nm laser for 15 min. A total of 3 times of assisted ALA-PDT was applied during and after operation. BCC was confirmed by pathological examination and the structure of tumor tissues was observed by transmission electron microscopy. Transmission electron microscopy showed that PDT had inhibitory effects on the growth of BCC by causing necrosis of tumor cells. There was no recurrence in the follow-up of 2.8 years (range, 0.6-5 years). The patients with infiltrative orbital BCC were able to complete the treatment protocol with good cosmetic results and no significant side effects. PDT in combination with limited surgery is a safe, effective and minimally-invasive approach for treating orbital BCC. Topical PDT during and after operation can reduce the excision range of the tumor lesions. Therefore, PDT may play a positive role in the treatment of periocular basal cell carcinoma.