LTA4H inhibitor LYS006: Clinical PK/PD and safety in a randomized phase I clinical trial

LYS006 is a novel, highly potent and selective, new-generation leukotriene A4 hydrolase (LTA4H) inhibitor in clinical development for the treatment of neutrophil-driven inflammatory diseases. We describe the complex pharmacokinetic to pharmacodynamic (PD) relationship in blood, plasma, and skin of LYS006-treated nonclinical species and healthy human participants. In a randomized first in human study, participants were exposed to single ascending doses up to 100 mg and multiple ascending doses up to 80 mg b.i.d.. LYS006 showed rapid absorption, overall dose proportional plasma exposure and nonlinear blood to plasma distribution caused by saturable target binding. The compound efficiently inhibited LTB4 production in human blood and skin blister cells, leading to greater than 90% predose target inhibition from day 1 after treatment initiation at doses of 20 mg b.i.d. and above. Slow re-distribution from target expressing cells resulted in a long terminal half-life and a long-lasting PD effect in ex vivo stimulated blood and skin cells despite low plasma exposures. LYS006 was well-tolerated and demonstrated a favorable safety profile up to highest doses tested, without any dose-limiting toxicity. This supported further clinical development in phase II studies in predominantly neutrophil-driven inflammatory conditions, such as hidradenitis suppurativa, inflammatory acne, and ulcerative colitis.

Anti-IL-17A blockade did not significantly reduce inflammatory lesions in a placebo-controlled pilot study in adult patients with moderate to severe acne

BACKGROUND

CJM112 is a potent anti-IL-17A monoclonal antibody, whose clinical efficacy in psoriasis was recently documented. This study aimed to assess the effect of IL-17A blockade, using CJM112, in patients with moderate to severe acne.

METHODS

A randomized, placebo-controlled, double-blind, parallel-group, proof-of-concept study was conducted on patients with moderate to severe acne. Patients received CJM112 300 mg, 75 mg, or placebo subcutaneously during Treatment Period 1 (0-12 weeks). Patients receiving placebo were re-randomized to receive CJM112 300 mg or 75 mg during Treatment Period 2 (12-24 weeks). The primary endpoint was the number of inflammatory facial lesions at Week 12.

RESULTS

As the futility criterion was met during the interim analysis, only 52/75 (69.3%) patients were recruited. In total, 48/52 (92.3%) and 26/41 (63.4%) completed Treatment Periods 1 and 2, respectively. All groups exhibited a reduction in facial inflammatory lesions, with no difference observed between CJM112 and placebo (CJM112 300 mg 27.6 ± 20.7; CJM112 75 mg 30.4 ± 34.8; placebo 23.6 ± 13.6; primary endpoint). Additionally, no differences were observed between groups in other secondary and exploratory endpoints at Week 12.

CONCLUSIONS

Anti-IL-17A therapy was not significantly different compared to the placebo in reducing inflammatory lesions in patients with moderate to severe acne.

IgE Depletion with Ligelizumab Does Not Significantly Improve Clinical Symptoms in Patients with Moderate-to-Severe Atopic Dermatitis

BACKGROUND

The value, if any, of anti-IgE approaches in the treatment of atopic dermatitis has not been fully clarified. Studies using the anti-IgE omalizumab have yielded conflicting results.

OBJECTIVE

Antibodies with an IgE-suppressive capacity stronger than omalizumab might be more efficacious.

STUDY DESIGN

We assessed the safety and efficacy of the high-affinity anti-IgE antibody ligelizumab (280 mg, subcutaneous, every other week) in 22 adult patients with moderate-to-severe atopic dermatitis in a placebo and active (cyclosporine A) controlled, randomized, multicenter, double-blind clinical trial for 12 weeks.

RESULTS

We found that ligelizumab treatment resulted in either complete (patients with baseline IgE < 1,500 IU/ml) or partial (baseline IgE > 1,500 IU/ml) suppression of serum and cell-bound IgE as well as of allergic skin prick tests. On the other hand, ligelizumab-as opposed to cyclosporine A-was not significantly superior to placebo in inducing Eczema Area and Severity Index 50 response or significantly reducing pruritus and sleep disturbance. Interestingly though, patients with high baseline IgE exhibited a slightly but not significantly better treatment response than those with low baseline IgE.

CONCLUSION

Our study shows that an immunologically efficacious anti-IgE approach is not clearly superior to placebo in treating atopic dermatitis. Larger studies are needed to determine whether certain patient subgroups may benefit from this strategy.

TRIAL REGISTRATION

The study was registered in 2011 at clinicaltrialsregister.eu, EudraCT Number 2011-002112-84.

Disease Association of Anti‒Carboxyethyl Lysine Autoantibodies in Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease characterized by recurring suppurating lesions of the intertriginous areas, resulting in a substantial impact on patients' QOL. HS pathogenesis remains poorly understood. An autoimmune component has been proposed, but disease-specific autoantibodies, autoantigens, or autoreactive T cells have yet to be described. In this study, we identify a high prevalence of IgM, IgG, and IgA antibodies directed against Nε-carboxyethyl lysine (CEL), a methylglyoxal-induced advanced glycation end-product, in the sera of patients with HS. Titers of anti-CEL IgG and IgA antibodies were highly elevated in HS compared with those in healthy controls and individuals with other inflammatory skin diseases. Strikingly, the majority of anti-CEL IgG was of the IgG2 subclass and correlated independently with both disease severity and duration. Both CEL and anti-CEL‒producing plasmablasts could be isolated directly from HS skin lesions, further confirming the disease relevance of this autoimmune response. Our data point to an aberration of the methylglyoxal pathway in HS and support an autoimmune axis in the pathogenesis of this debilitating disease.

IL-17A is a pertinent therapeutic target for moderate-to-severe hidradenitis suppurativa: Combined results from a pre-clinical and phase II proof-of-concept study

Hidradenitis Suppurativa (HS) is a chronic, recurrent, inflammatory, follicular skin disease whose pathology is complex and not fully understood. The objective of this study was to elucidate the role of IL-17A in moderate-to-severe HS. Transcriptomic and histological analyses were conducted on ex vivo HS (n = 19; lesional and non-lesional) and healthy control (n = 8) skin biopsies. Further, a Phase II exploratory, randomized, double-blind, placebo-controlled study was carried out in moderate-to-severe HS patients. Patients were treated with either CJM112 300 mg (n = 33), a fully human anti-IL-17A IgG1/κ monoclonal antibody, or placebo (n = 33). The main outcome of the translational analyses was to identify IL-17A-producing cells and indications of IL-17A activity in HS lesional skin. The primary objective of the clinical study was to determine the efficacy of CJM112 in moderate-to-severe HS patients by HS-Physician Global Assessment (HS-PGA) responder rate at Week 16. Transcriptomic and histopathologic analyses revealed the presence of heterogeneous cell types in HS lesional skin; IL-17A gene signatures were increased in HS lesional vs non-lesional or healthy skin. High expression of IL-17A was localized to T cells, neutrophils, and mast cells, confirming the transcriptional data. Clinically, the proportion of Week 16 HS-PGA responders was significantly higher (p = 0.03) in the CJM112 group vs placebo (32.3% vs 12.5%). This study elucidated the role of the IL-17A pathway in HS pathogenesis and clinically validated the IL-17A pathway in moderate-to-severe HS patients in a proof-of-concept study using the anti-IL-17A-specific antibody CJM112.

Drug discovery strategies for novel leukotriene A4 hydrolase inhibitors

IntroductionLeukotriene A4 hydrolase (LTA4H) is the final and rate limiting enzyme regulating the biosynthesis of leukotriene B4 (LTB4), a pro-inflammatory lipid mediator implicated in a large number of inflammatory pathologies. Inhibition of LTA4H not only prevents LTB4 biosynthesis but also induces a lipid mediator class-switch within the 5-lipoxygenase pathway, elevating biosynthesis of the anti-inflammatory lipid mediator Lipoxin A4. Ample preclinical evidence advocates LTA4H as attractive drug target for the treatment of chronic inflammatory diseases.Areas coveredThis review covers details about the biochemistry of LTA4H and describes its role in regulating pro- and anti-inflammatory mediator generation. It summarizes recent efforts in medicinal chemistry toward novel LTA4H inhibitors, recent clinical trials testing LTA4H inhibitors in pulmonary inflammatory diseases, and potential reasons for the discontinuation of former development programs.Expert opinionGiven the prominent role of LTB4 in initiating and perpetuating inflammation, LTA4H remains an appealing drug target. The reason former attempts targeting this enzyme have not met with success in the clinic can be attributed to compound-specific liabilities of first-generation inhibitors and/or choice of target indications to test this mode of action. A new generation of highly potent and selective LTA4H inhibitors is currently undergoing clinical testing in indications with a strong link to LTB4 biology.

Lipidomics Profiling of Hidradenitis Suppurativa Skin Lesions Reveals Lipoxygenase Pathway Dysregulation and Accumulation of Proinflammatory Leukotriene B4

Hidradenitis suppurativa (HS) is a chronic, recurring inflammatory dermatosis characterized by abscesses, deep-seated nodules, sinus tracts, and fibrosis in skin lesions around hair follicles of the axillary, inguinal, and anogenital regions. Whereas the exact pathogenesis remains poorly defined, clear evidence suggests that HS is a multifactorial inflammatory disease characterized by innate and adaptive immune components. Bioactive lipids are important regulators of cutaneous homeostasis, inflammation, and resolution of inflammation. Alterations in the lipid mediator profile can lead to malfunction and cutaneous inflammation. We used targeted lipidomics to analyze selected omega-3 and omega-6 polyunsaturated fatty acids in skin of patients with HS and of healthy volunteers. Lesional HS skin displayed enrichment of 5-lipoxygenase (LO)‒derived metabolites, especially leukotriene B4. In addition, 15-LO‒derived metabolites were underrepresented in HS lesions. Changes in the lipid mediator profile were accompanied by transcriptomic dysregulation of the 5-LO and 15-LO pathways. Hyperactivation of the 5-LO pathway in lesional macrophages identified these cells as potential sources of leukotriene B4, which may cause neutrophil influx and activation. Furthermore, leukotriene B4-induced mediators and pathways were elevated in HS lesions, suggesting a contribution of this proinflammatory lipid meditator to the pathophysiology of HS.

Population Pharmacokinetic Modeling of Secukinumab in Patients With Moderate to Severe Psoriasis

Secukinumab is a human monoclonal antibody with demonstrated efficacy for moderate to severe psoriasis; it binds to and neutralizes interleukin (IL)-17A. The pharmacokinetic (PK) parameters of secukinumab were best described by a 2-compartment model. Only weight was included in the final model, as other covariates did not affect clinical relevance. The estimated serum clearance of secukinumab was 0.19 L/day, with interindividual variability (IIV) of 32% coefficient of variation (CV), and low total volume of distribution (central compartment volume, 3.61 L with IIV of 30% CV; peripheral compartment volume, 2.87 L with IIV of 18% CV). The bioavailability of secukinumab after subcutaneous dosing was approximately 73%, with an absorption rate of 0.18/day with IIV of 35% CV. The PK profile of secukinumab was linear, with no evidence of a dose dependence of clearance. Clearance and volume of secukinumab varied with body weight in an allometric relationship. The time to maximum serum concentration at steady state occurred approximately 6 days after dosing for both secukinumab 300 mg and secukinumab 150 mg. Overall, the PK properties of secukinumab were typical of a 150-kDa human IgG1 antibody interacting with a soluble target.

Interleukin-17A blockade with secukinumab results in decreased neutrophil infiltration in psoriasis: minimally-invasive measurement by tape stripping

Psoriasis is a well characterized interleukin (IL)-17A-driven skin disease with neutrophil infiltration and epidermal hyperkeratosis. Several biomarkers, most prominently β-defensin-2 (BD-2), have been identified using local and systemic invasive measurements as responsive markers of IL-17A-driven skin pathology. We sought to determine whether measurements of epidermal proteins by tape stripping could offer a minimally-invasive method to assess treatment responses. We compared the expression of 170 proteins in the epidermis (tape stripping) and dermis (open flow microperfusion) of 8 psoriatic subjects before and after administration of a single dose of subcutaneous (s.c.) antiIL-17A mAb secukinumab. Proteomic analyses of tape strips revealed a >3-fold decrease in 32 epidermal and inflammatory cell proteins in response to secukinumab. The epidermal proteins with the largest (>10-fold) decreases were: matrix metalloproteinase-8 (MMP-8, 15.68-fold, p<0.05); myeloperoxidase (MPO, 14.72-fold, p<0.005); IL-8 (11.93-fold, p<0.05); MMP-9 (10.81-fold, p<0.005); and IL-1β (10.35-fold, p<0.05). For these proteins, greater-fold protein changes were detected in the epidermis compared to dermis. Immunohistochemical analysis confirmed that neutrophils are the predominant cell type in psoriatic skin lesions that express MPO, MMP-8 and MMP-9, and that secukinumab treatment dramatically decreases neutrophil accumulation. Thus, tape stripping may be used to assess epidermal neutrophils, and protein biomarker responses to anti-IL-17A therapy in psoriasis.

A new ecamsule-containing SPF 40 sunscreen cream for the prevention of polymorphous light eruption: a double-blind, randomized, controlled study in maximized outdoor conditions

Polymorphous light eruption (PMLE) is an idiopathic photodermatosis elicited by UV radiation (UVR). The objective of this double-blind, randomized, controlled, intraindividual, bilateral comparison was to determine the efficacy of the UVA filters (ecamsule, avobenzone) present in the new sun protection factor (SPF) 40 sunscreen cream in preventing PMLE in maximized outdoor conditions (ie, exaggerated sun exposure). Safety also was assessed. Each participant was treated with SPF 40 sunscreen cream containing ecamsule 3%, octocrylene 10%, avobenzone 2%, and titanium dioxide 5% (tetrad) on one side of the body and either an ecamsule-deprived (triad-E) or avobenzone-deprived (triad-A) cream on the other side. Participants were subsequently exposed to incremental doses of sunlight for up to 6 days. The primary efficacy assessment was a composite relative success rate with 3 components. Success was defined as either a delayed time to onset of PMLE or a lower global severity of PMLE comparing one side of the body to the other side in the same participant. Safety evaluations included systemic adverse events (AEs). Of the 144 participants enrolled and randomized, 22 did not experience PMLE during the study duration under these maximized sun exposure conditions. A significantly greater number of successes were detected on the tetrad-treated side compared with either triad: 41 of 73 participants (56%) versus 8 of 73 participants (11%; P<.001) in the triad-E treatment group and 26 of 71 participants (36%) versus 11 of 71 participants (16%; P=.02) in the triad-A treatment group. Polymorphous light eruption appeared later with the tetrad than with either triad. The global severity of the PMLE flares was significantly lower with the tetrad than with both triads at end point (P<.001 and P=.02 for tetrad vs triad-E and tetrad vs triad-A, respectively). In this study, the SPF 40 sunscreen cream containing ecamsule 3%, octocrylene 10%, avobenzone 2%, and titanium dioxide 5% prevented PMLE flares significantly better than similar formulations with only one of the UVA filters (triad-E treatment group, P<.001; triad-A treatment group, P=.02). The inclusion of both ecamsule and avobenzone provides clinical benefit to patients with PMLE compared with formulations containing only one UVA filter.

Cumulative irritation comparison of adapalene gel and solution with 2 tazarotene gels and 3 tretinoin formulations

Forty-two subjects with normal skin were enrolled in a single-center study to assess the cumulative irritancy potential of adapalene (Differin gel 0.1% and Differin solution 0.1%) compared with tazarotene (Tazorac gels 0.05% and 0.1%), tretinoin (Retin-A Micro gel 0.1%, Avita cream 0.025%, and Avita gel 0.025%), and white petrolatum (negative control). All test materials were applied randomly, under occlusion, to sites located on either side of the midline--the mid thoracic area of the subjects' backs. All patches were applied daily, Monday through Friday, to the same sites, unless the degree of reaction to a test product or adhesive necessitated removal (grade 3). Thirty-eight of the 42 subjects (90.5%) completed the study. Thirty-four of those 38 subjects (89.5%) had to discontinue using both tazarotene concentrations due to intolerance. Patch discontinuations for the remaining test materials were as follows: 7 subjects discontinued use of tretinoin microsphere gel 0.1%, 3 discontinued tretinoin cream 0.025%, 1 discontinued tretinoin gel 0.025%, and 1 discontinued adapalene gel 0.1%. None of the subjects discontinued use of the white petrolatum or the adapalene solution 0.1%. Adapalene gel and solution 0.1% were statistically (P<.01) less irritating than both tazarotene gels 0.1% and 0.05%, tretinoin microsphere gel 0.1%, and tretinoin gel 0.025%, and they were not statistically different from tretinoin gel 0.025%.

Randomized controlled trial of the tolerability, safety, and efficacy of adapalene gel 0.1% and tretinoin microsphere gel 0.1% for the treatment of acne vulgaris

A prior meta-analysis of 5 randomized controlled trials indicates that adapalene gel 0.1% is as effective as tretinoin gel 0.025% against acne and has greater tolerability. To determine the tolerability and efficacy of adapalene gel 0.1% versus tretinoin microsphere gel 0.1% in 168 patients with acne vulgaris, we conducted a 12-week, multicenter, randomized, controlled, investigator-masked, parallel-group design study. Efficacy variables included noninflammatory, inflammatory, and total lesion counts; global grade; and global assessment of improvement in acne severity. Skin tolerability variables included erythema, desquamation (scaling), dryness, pruritus, and stinging/burning. Our results showed that the efficacy of adapalene gel 0.1% was comparable to that of tretinoin microsphere gel, and both treatments had similar onset of action. Cutaneous tolerability was noted in both groups, with scores significantly better with adapalene gel 0.1% than with tretinoin microsphere gel 0.1%, and significantly fewer treatment-related adverse events were reported with adapalene gel 0.1%.

A comparison of the efficacy and tolerability of adapalene 0.1% gel versus tretinoin 0.025% gel in patients with acne vulgaris: a meta-analysis of five randomized trials

The purpose of this meta-analysis was to determine if adapalene 0.1% gel (Differin) provided superior efficacy and better tolerability than tretinoin 0.025% gel in the treatment of acne vulgaris. All comparative studies, both published and unpublished, from the United States and Europe, that fulfilled rigorous protocol criteria (multicentre, randomized, investigator-blind) were used. Five comparative studies met these criteria. In total, the meta-analysis evaluated 900 patients (450 treated with adapalene 0.1% gel, 450 treated with tretinoin 0.025% gel) with mild-to-moderate acne from the combined clinical trials. To avoid study bias, the meta-analysis used an intention-to-treat analysis. Statistical methodology for the meta-analysis included analysis of covariance, analysis of variance and Cochran-Mantel-Haenszel test. All statistical tests were two-sided, with the 0.05 probability level used to establish statistical significance, and 95% confidence intervals used to assess equivalence. Adapalene demonstrated equivalent efficacy to tretinoin in terms of reducing total lesion count. Adapalene demonstrated more rapid efficacy, as evidenced by a significant difference in the reduction of inflammatory and total lesions at week 1. Adapalene also demonstrated considerably greater local tolerability at all evaluation periods. The findings from this meta-analysis suggest that adapalene 0.1% gel constitutes a pharmacologic advance over such classic retinoids as tretinoin for the treatment of acne vulgaris.

Comparison of adapalene 0.1% solution and tretinoin 0.025% gel in the topical treatment of acne vulgaris

A multicentre study was conducted to compare clinical safety and efficacy of adapalene 0.1% solution and tretinoin 0.025% gel, both topical treatments for acne, in a once-daily dosage regimen for 12 weeks. A total of 297 patients were enrolled by eight investigators in this randomized, investigator-masked study in a parallel group design. An open label period using adapalene followed this study to assess the long-term safety of adapalene solution. Adapalene and tretinoin proved to be clinically and statistically effective in treating acne by reducing inflammatory (47% and 50%, respectively) and non-inflammatory lesions (57% and 54%) as compared to baseline. When comparing patients who had 75% or greater improvement in open comedones, adapalene was shown to be significantly more effective than tretinoin. No serious adverse event was reported during this study, including during the long-term period. The reactions that occurred were similar between treatments, i.e. burning, pruritus, scaling, dryness and erythema.

[Exogenous photosensitizing agents]

The frequent use of remedies either in topical or systemic form has led to a rising number of photosensitizations. The different cutaneous manifestations of exogenous photosensitizers e.g. phototoxicity and photoallergy, are described. We treat the most important agents of these reactions and lay stress upon the patient's interview and the phototesting in order to find out the substance, that induced photodermatosis.

Variation in 8-methoxypsoralen profiles during long-term psoralen plus ultraviolet A therapy and correlations between serum 8-methoxypsoralen levels and chromametric parameters

Three serum 8-methoxypsoralen (8-MOP) kinetics tests were performed on 15 patients undergoing PUVA therapy. The first test was carried out before beginning PUVA treatment, the 2nd one at the 10th session and the 3rd test at the 20th PUVA session. Blood samples were taken every 30 min after the drug was taken and a standard meal ingestion during 3 h to determine the serum 8-MOP peak level and corresponding time. For 14 patients, UVA-induced erythema was measured with a Minolta CR 200 chromameter, 3 (before beginning PUVA treatment, just before 10th session and 48 h later) or 5 times (before beginning PUVA treatment, just before 10th session and 48 h later, just before 20th session and 48 h later). There was a wider distribution of serum 8-MOP peak levels in the 3rd test than in 2nd one and in the 2nd one than in the first one. These facts suggest a heterogeneity in 8-MOP metabolism in the 15 patients: 11 patients showed an earlier serum 8-MOP peak and an earlier appearance of the drug in blood in the 3rd and 2nd test than in the first one. For 9 of these 11 patients, serum 8-MOP peak levels were higher and higher from the first profile to the 3rd one, suggesting an inhibition of 8-MOP metabolism in time. In the remaining 4 patients, the 8-MOP peak time and the appearance of the drug in blood were delayed in the 3rd test compared with the first profile.(ABSTRACT TRUNCATED AT 250 WORDS)