Evaluation of the tolerability and safety of a 0.015% ingenol mebutate gel compared to 5% 5-fluorouracil cream for the treatment of facial actinic keratosis: a prospective randomized trial

Why Is Wnt/β-Catenin Not Yet Targeted in Routine Cancer Care?

Despite significant progress in cancer prevention, screening, and treatment, the still limited number of therapeutic options is an obstacle towards increasing the cancer cure rate. In recent years, many efforts were put forth to develop therapeutics that selectively target different components of the oncogenic Wnt/β-catenin signaling pathway. These include small molecule inhibitors, antibodies, and more recently, gene-based approaches. Although some of them showed promising outcomes in clinical trials, the Wnt/β-catenin pathway is still not targeted in routine clinical practice for cancer management. As for most anticancer treatments, a critical limitation to the use of Wnt/β-catenin inhibitors is their therapeutic index, i.e., the difficulty of combining effective anticancer activity with acceptable toxicity. Protecting healthy tissues from the effects of Wnt/β-catenin inhibitors is a major issue due to the vital role of the Wnt/β-catenin signaling pathway in adult tissue homeostasis and regeneration. In this review, we provide an up-to-date summary of clinical trials on Wnt/β-catenin pathway inhibitors, examine their anti-tumor activity and associated adverse events, and explore strategies under development to improve the benefit/risk profile of this therapeutic approach.

Immunomodulators for Non-Melanoma Skin Cancers: Updated Perspectives

Non-melanoma skin cancers (NMSCs) are the most common cancers worldwide and may be associated with significant morbidity and mortality, especially in immunosuppressed populations. Successful management of NMSC must take primary, secondary and tertiary prevention strategies into consideration. In response to an improved understanding of the pathophysiology of NMSC and associated risk factors, multiple systemic and topical immunomodulatory drugs have been developed and integrated into clinical practice. Many of these drugs are efficacious in the prevention and treatment of precursor lesions (actinic keratoses; AKs), low-risk NMSC, and advanced disease. The identification of patients at high risk for the development of NMSC is critical in reducing disease morbidity. Understanding the various treatment options available and their comparative effectiveness is paramount for developing a personalized treatment regimen for such patients. This review article provides an updated overview of the various topical and systemic immunomodulatory drugs available for the prevention and treatment of NMSC, and the published data supporting their use in clinical practice.

Comparative Efficacy and Safety of Tirbanibulin for Actinic Keratosis of the Face and Scalp in Europe: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

Actinic keratosis (AK) is a chronic skin condition that may progress to cutaneous squamous cell carcinoma. We conducted a systematic review of efficacy and safety for key treatments for AK of the face and scalp, including the novel 5-day tirbanibulin 1% ointment. MEDLINE, PubMed, Embase, Cochrane Library, clinical trial registries and regulatory body websites were searched. The review included 46 studies, of which 35 studies included interventions commonly used in Europe and were sufficiently homogenous to inform a Bayesian network meta-analysis of complete clearance against topical placebo or vehicle. The network meta-analysis revealed the following odds ratios and 95% credible intervals: cryosurgery 13.4 (6.2–30.3); diclofenac 3% 2.9 (1.9–4.3); fluorouracil 0.5% + salicylic acid 7.6 (4.6–13.5); fluorouracil 4% 30.3 (9.1–144.7); fluorouracil 5% 35.0 (10.2–164.4); imiquimod 3.75% 8.5 (3.5–22.4); imiquimod 5% 17.9 (9.1–36.6); ingenol mebutate 0.015% 12.5 (8.1–19.9); photodynamic therapy with aminolevulinic acid 24.1 (10.9–52.8); photodynamic therapy with methyl aminolevulinate 11.7 (6.0–21.9); tirbanibulin 1% 11.1 (6.2–20.9). Four sensitivity analyses, from studies assessing efficacy after one treatment cycle only, for ≤25 cm² treatment area, after 8 weeks post-treatment, and with single placebo/vehicle node confirmed the findings from the base case. Safety outcomes were assessed qualitatively. These results suggest that tirbanibulin 1% offers a novel treatment for AK, with a single short treatment period, favourable safety profile and efficacy, in line with existing topical treatments available in Europe.

Actinic keratoses: review of clinical, dermoscopic, and therapeutic aspects

Actinic keratoses are dysplastic proliferations of keratinocytes with potential for malignant transformation. Clinically, actinic keratoses present as macules, papules, or hyperkeratotic plaques with an erythematous background that occur on photoexposed areas. At initial stages, they may be better identified by palpation rather than by visual inspection. They may also be pigmented and show variable degrees of infiltration; when multiple they then constitute the so-called field cancerization. Their prevalence ranges from 11% to 60% in Caucasian individuals above 40 years. Ultraviolet radiation is the main factor involved in pathogenesis, but individual factors also play a role in the predisposing to lesions appearance. Diagnosis of lesions is based on clinical and dermoscopic examination, but in some situations histopathological analysis may be necessary. The risk of transformation into squamous cell carcinoma is the major concern regarding actinic keratoses. Therapeutic modalities for actinic keratoses include topical medications, and ablative and surgical methods; the best treatment option should always be individualized according to the patient.

Efficacy and safety of ingenol mebutate gel in field treatment of actinic keratosis on full face, balding scalp, or approximately 250 cm2 on the chest: A phase 3 randomized controlled trial

BACKGROUND

Ingenol mebutate (IngMeb) 0.015% or 0.05% is approved for actinic keratosis (AK) areas of 25 cm² or less; some patients require treatment of larger fields.

OBJECTIVE

To determine efficacy and safety of IngMeb 0.027% in areas of AK of up to 250 cm² during an 8-week initial assessment period and extended 12-month follow-up.

METHODS

This phase 3, randomized, double-blind, vehicle-controlled trial (NCT02361216) enrolled adult patients with 5 to 20 AK lesions on the face/scalp (25-250 cm²) or chest (approximately 250 cm²). Patients received once-daily IngMeb or vehicle for 3 consecutive days on the full face, full balding scalp, or approximately 250 cm² on the chest. The primary endpoint was complete AK clearance (AKCLEAR 100; week 8). Additional endpoints included partial AK clearance (AKCLEAR 75), recurrence, patient satisfaction, cosmetic outcome, and safety.

RESULTS

IngMeb was superior to vehicle for complete AK clearance (21.4% vs 3.4%, P < .001) and AK clearance of 75% or greater (59.4% vs 8.9%, P < .001) at week 8. Probability of sustained clearance during the 12-month follow-up was 22.9% for patients treated with IngMeb. Increased treatment satisfaction and cosmetic outcomes were observed with IngMeb versus vehicle. No unexpected safety signals were identified.

LIMITATIONS

Localized skin responses hindered maintenance of double-blinding.

CONCLUSIONS

IngMeb 0.027% was superior to vehicle for treatment of AK areas of up to 250 cm². The safety profile of IngMeb was as expected.

Treatment of actinic keratoses and cancerization field of the face and scalp with 0.015% ingenol mebutate gel in Brazilian individuals: safety, tolerability and patients' perspectives

BACKGROUND

Actinic keratosis (AK) represents a risk of progression to squamous cell carcinoma. Ingenol mebutate gel is a novel therapeutic option for field-directed treatment.

OBJECTIVES

To evaluate the safety, tolerability and patients' perspectives, related to the therapeutic success of managing AKs on the face and scalp with ingenol mebutate gel in Brazilian individuals.

METHODS

This was an observational, retrospective and descriptive study of 68 areas of actinic keratosis on the face and scalp treated with Ingenol mebutate gel involving a total of 37 patients. The drug was applied for three consecutive days on an area of of 25 cm2 and documentation was performed on baseline and days 4, 8, 15, 60 and 180. On day 4, the composite local skin reaction score was calculated. At the end, a questionnaire was applied to evaluate patients' perspectives about the treatment.

RESULTS

Adherence was 100%, no serious adverse events were recorded and the mean composite local skin reaction score (standard deviation) was 8.61±4.22. The treatment was considered optimum by 75.68% of the patients.

STUDY LIMITATIONS

Calculation of composite local skin reaction score performed only on the fourth day.

CONCLUSIONS

Treatment with ingenol mebutate gel was considered safe and tolerable in Brazilian subjects. Patients had a maximum adherence rate and a great improvement in self-esteem. The results of this research reproduce the findings of the literature.

Prevalence, Discontinuation Rate, and Risk Factors for Severe Local Site Reactions with Topical Field Treatment Options for Actinic Keratosis of the Face and Scalp

Actinic keratoses (AKs) are common lesions on chronically sun damaged skin, which are morphologically characterized by lower third to full thickness atypia of epidermal keratinocytes. These lesions carry a risk of progression towards invasive squamous cell carcinoma (SCC); therefore, treatment of visible lesions and the field in case of field cancerization is recommended. Treatment of AK includes the destruction of atypical keratinocytes that clinically presents with various degrees of erythema, scaling, crusting, erosion, and other visible and subjective symptoms. Such inflammatory reactions may have an impact on the patient’s social life and have shown to decrease compliance and adherence to therapy. Additionally, as various topical treatments have been proven to be effective in treating AK, tolerability of local site reactions (LSRs) might drive the decision for appropriate treatment in an individual scenario. Therefore, we aimed to review prevalence of severe LSRs among various topical treatments for AK. In addition, we summarized discontinuation rates due to LSRs and possible therapy-unrelated risk factors for the development of LSRs with increased severity.

A randomized, open, controlled trial of tretinoin 0.05% cream vs. low-dose oral isotretinoin for the treatment of field cancerization

BACKGROUND

Sun exposure may lead to actinic keratoses (AKs), field cancerization, and skin cancer. Effective treatment of AKs and field cancerization is important. Oral and topical retinoids can be used for this purpose. To compare clinical, histological, and immunohistochemical effects of oral and topical retinoid for AKs and field cancerization on face and upper limbs of immunocompetent patients, as well as the impact on quality of life, safety, and tolerability.

METHODS

This study compared 10 mg/day oral isotretinoin (ISO) to 0.05% tretinoin cream (TRE) every other night, associated with sunscreen (SPF 60). Patients of both genders, aged 50-75 years, underwent cryotherapy with liquid nitrogen for AKs at baseline and after 120 days when they were randomized into two groups, TRE (n = 31) and ISO (n = 30), for 6 months. Outcome measures were: number of AKs, histological (thickness of stratum corneum and epithelium) and immunohistochemical parameters (p53, Bcl-2 and Bax), dermatology life quality index (DLQI), and adverse events.

RESULTS

Both treatments reduced the number of AKs (around 28%), the thickness of stratum corneum, and expression of p53 and Bax. By contrast, the epithelium thickness and Bcl-2 expression increased. There was no difference in the outcomes between TRE and ISO. Both treatments improved quality of life and were well tolerated with minimal side effects.

CONCLUSIONS

Retinoids are effective and safe for field cancerization. Classical treatments for field cancerization (imiquimod and ingenol mebutate) are used for a short period; retinoids may be a good choice to intercalate with them and can be used continuously.

Ingenol mebutate in the treatment of actinic keratoses: clearance rate and adverse effects

BACKGROUND

Actinic keratoses are benign intraepithelial skin neoplasms that develop in photoexposed areas and can progress to invasive carcinoma. They are seen frequently in dermatological practice, occurring in 5.1% of consultations. Ingenol mebutate (IM) was recently approved in Brazil as a topical therapy for field cancerization in actinic keratosis.

OBJECTIVE

To evaluate the clearance rate and adverse events in the treatment of actinic keratoses with ingenol mebutate.

METHODS

A longitudinal, prospective, non-randomized, interventional, open, single-center study was conducted. Patients with actinic keratoses applied ingenol mebutate on a 25cm2 area of the face and/or scalp for three consecutive days (0.015%) or on the forearm for two days (0.05%).

RESULTS

27 patients completed the protocol, of whom 13 on the face and/or scalp and 14 on the forearm. Complete clearance occurred in 53.8% in the first group and 42.8% in the second. Partial response was observed in 15.4% and 35.7%, respectively. The most common side effects were erythema, edema, desquamation, pruritus, and local erosion.

STUDY LIMITATIONS

The study had a small sample and was not randomized, double-blind, placebo-controlled, or vehicle-controlled.

CONCLUSION

Ingenol mebutate is well-tolerated for the treatment of actinic keratosis, with good patient adherence thanks to the short treatment period.

Treatment considerations in actinic keratosis

The chronic skin condition actinic keratosis (AK) is characterized by the formation of keratotic lesions of variable thickness that are poorly delimited. AK occurs on areas of the skin that have had long-term exposure to the sun or UV radiation. Although AKs may regress, they usually persist and can progress to squamous cell carcinoma (SCC). Clinicians are unable to predict which AKs will progress; therefore, both clinically visible lesions and subclinical, non-visible (i.e. the entire area affected by AK/field cancerization) should be treated. AK treatment options include lesion-directed therapies that target specific AK lesions and field-directed therapies that target multiple clinical lesions and the underlying field damage. This article reviews currently available treatment options in AK, with a focus on patient-applied field therapies, and their suitability according to specific disease characteristics and patient needs. Choice of treatment in AK depends on lesion-, patient- and treatment-related factors and should be individualized. Considerations when choosing a therapy include site of application, treatment duration, surface area of application, tolerability profiles and implications on adherence. Field-directed therapies treat clinical and subclinical damage (i.e. the entire area affected by AK), achieve high rates of sustained clearance of AKs and may reduce the risk of progression to SCC. There is a clear need for field therapies with short duration of treatment and predictable, short-lived, mild local skin reactions that can be used over a large surface area. Therapies with shorter and simpler treatment courses are often associated with better adherence than treatments with longer courses. These may, therefore, represent more appropriate choices in patients for whom convenience and/or adherence are an issue.

A randomized split-face clinical trial analyzing daylight photodynamic therapy with methyl aminolaevulinate vs ingenol mebutate gel for the treatment of multiple actinic keratoses of the face and the scalp

INTRODUCTION

Daylight photodynamic therapy with methyl aminolaevulinate (dlPDT) and ingenol mebutate gel (IMB) are approved therapeutic options for multiple actinic keratoses (AKs). The aim of this comparative, intra-patient, split-face, randomized clinical trial was to compare treatment outcomes of dlPDT and IMB.

METHODS

Two symmetrical contralateral areas of 25cm², harboring a similar (5-10) number of AKs, were selected and randomly assigned either to a 3days' IMB treatment cycle or to a single session of dlPDT. The day after the local skin reaction (LSR) score was registered. Patients' scored pain (assessed through VAS method) after the treatment, and time needed for wound closure, were subsequently registered. After 90days, the complete remission (CR) rate recorded for both single lesions and patients, the cosmetic outcome and the patients' preference, were assessed.

RESULTS

22 patients with a total of 311 AKs were enrolled. The mean pain VAS score was 3.55±1.82 with IMB and 2.05±0.72 with dlPDT (p<0.01). The mean LSR score was 9.91±4.24 and 4.59±4.03 (p<0.01), respectively. The mean days necessary for wound closure were 9.45±3.51 and 4.36±1.18days (p<0.01), respectively. After 3 months, 119 lesions with IMB and 120 lesions with dlPDT were healed and the CR rate with IMB (75.8%) was non-inferior to the CR rate with dlPDT (77.9%). The comparisons of CR rates of grade I and II AKs did not show any inferiority for one treatment compared to the other. Eight patients (36.4%) had all lesions cleared with IMB and 7 (31.8%) with dlPDT (p=NS). The cosmetic outcome was better with dlPDT and 17 patients evaluated dlPDT as their preferred treatment.

CONCLUSIONS

A 3days' treatment cycle with IMB and a single session of dlPDT had a similar efficacy for both grade I AKs and grade II AKs but dl PDT showed lower pain and inflammation scores, quicker wound closure, better cosmetic outcome and higher patients' preference.

Efficacy, safety and tolerability of field treatment of actinic keratosis with ingenol mebutate 0.015 % gel: a single center case series

Introduction

Actinic keratosis (AK) is a cutaneous intraepithelial neoplasm appearing within areas referred as ‘fields of cancerization’. AK can progress to invasive squamous cell carcinoma. Treatments that target both clinically visible and subclinical AKs in cancerization fields are able to reduce the risk of malignant progression. Ingenol mebutate gel is a new effective topical therapy for AK, used once daily for 2 or 3 days depending on the location of lesions.

Case description

Three elderly patients with multiple non-hypertrophic AKs within a contiguous 25-cm² treatment area on the face or scalp were treated with ingenol mebutate 0.015 % gel once daily for three consecutive days and followed up over a period of 57 days.

Discussion and Evaluation

Although individual local responses to treatment varied, all patients had total clearance of AK lesions without any sign of recurrence. In addition, all patients said that they were satisfied with the effectiveness of ingenol mebutate treatment and the aesthetic outcome, and would be prepared to use this agent again to treat AK in the future, if necessary.

Conclusions

These three cases demonstrate that ingenol mebutate 0.015 % gel is effective and well tolerated in a clinical setting, with effective clearance of AK lesions present on the face and scalp, and good patient acceptability.

Actinic keratosis and field cancerization

While actinic keratoses (AKs) have been considered precancerous until recently for being able to turn into squamous cell carcinomas (SCCs), it is now agreed that it would be more appropriate to call them cancerous. Although not all AKs turn into SCC and some of them may even have a spontaneous regression, there is an obvious association between SCC and AK. Approximately 90% of SCs have been reported to develop from AKs and AKs are the preinvasive form of SCCs. The presence of two or more AKs on a photodamaged skin is an indicator of field cancerization and represents an increased risk of invasive SCC. All lesions should be treated since it cannot be foreseen which of the lesions will regress and which will progress to SCC. AK can be a single lesion or it can involve multiple lesions in a field of cancerization; thus, AK treatment is grouped under two headings: (1) Lesion-specific treatment; and (2) Field-targeted treatment. Lesion-specific treatments are practicable in patients with a small number of clinically visible and isolated lesions. These treatments including cryotherapy, surgical excision, shave excision, curettage and laser are based on physical destruction of the visible lesions. Field-targeted treatments are effective in the treatment of visible lesions, subclinical lesions and keratinocyte changes in the areas surrounding the visible lesions. Field targeted treatment options are topical imiquimod cream, 5% 5-fluorouracil cream, ingenol mebutate, diclofenac gel, resimiquimod and photodynamic therapy.

Efficacy and safety of follow-up field treatment of actinic keratosis with ingenol mebutate 0·015% gel: a randomized, controlled 12-month study

BACKGROUND

Ingenol mebutate (IngMeb) is a novel patient-applied topical field therapy for actinic keratosis.

OBJECTIVES

To demonstrate the efficacy and safety of follow-up IngMeb field treatment of actinic keratoses (AKs) present at 8 weeks after initial treatment or emerging in a previously cleared field.

METHODS

In this phase III, randomized, double-blind study in patients with 4-8 clinically visible AKs within a contiguous 25-cm(2) treatment area on the face or scalp, all patients were treated initially with IngMeb 0·015% gel for three consecutive days. If lesions were present in the field at 8 weeks, or emerged at weeks 26 or 44, patients were randomized (2 : 1) to follow-up IngMeb or vehicle gel for three consecutive days. The main outcome was complete clearance rates of AKs 8 weeks after randomization.

RESULTS

Of 450 patients who received initial treatment with IngMeb, 61·6% demonstrated complete clearance at 8 weeks. Patients with AKs present at 8 weeks or emerging at weeks 26 or 44 were randomized to IngMeb (n = 134) or vehicle (n = 69). IngMeb achieved a higher complete clearance rate than vehicle 8 weeks after randomization in AKs present at 8 weeks (46·7% vs. 18·4%; P < 0·01) and in emergent AKs (59·5% vs. 25·0%; P = 0·01). Based on those who completed 12 months of follow-up (n = 340), the overall 12-month clearance rate was estimated at 50·0%. Follow-up IngMeb treatment was well tolerated.

CONCLUSIONS

This study demonstrated the long-term benefit of IngMeb 0·015% gel for initial and follow-up therapy of AKs.

Safety and tolerability of ingenol mebutate in the treatment of actinic keratosis

INTRODUCTION

Ingenol mebutate is a topical therapeutic agent for the treatment of actinic keratosis (AK). It has a novel mode of action and has shown comparable efficacy to other topical field therapies. This article summarizes and provides perspective on the safety profile of ingenol mebutate from clinical studies of this agent.

AREAS COVERED

The unique mechanism of action of ingenol mebutate, the basis for a rapid clinical effect, is outlined. Safety and tolerability data, including mean composite local skin response (LSR) scores, type of LSR, and adverse events from a range of clinical studies both in healthy volunteers and patients with AK, are reviewed. The safety profile of ingenol mebutate is then compared with other agents used to treat AK lesions.

EXPERT OPINION

Ingenol mebutate has a dosing period of 2 - 3 days, which is short compared with other field therapies, and there is no evidence of systemic absorption. The fact that most of the LSRs observed are mild to moderate in intensity and transient, with a majority resolved within 2 weeks, makes for a favorable safety profile. Ingenol mebutate enhances the armamentarium available to the dermatologist for the treatment of AK.