Efficacy and safety of topical JTE-052, a Janus kinase inhibitor, in Japanese adult patients with moderate-to-severe atopic dermatitis: a phase II, multicentre, randomized, vehicle-controlled clinical study.

BACKGROUND: JTE-052 is a novel Janus kinase inhibitor presently under clinical development for the topical treatment of atopic dermatitis (AD). OBJECTIVES: To evaluate the efficacy and safety of JTE-052 ointment in Japanese adult patients with AD. METHODS: Patients with moderate-to-severe AD were randomized (2: 2: 2: 2: 1: 1) to receive JTE-052 ointment at 0·25%, 0·5%, 1% or 3%, the vehicle ointment or tacrolimus 0·1% ointment (reference) twice daily for 4 weeks. The primary efficacy end point was the percentage change in modified Eczema Area Severity Index (mEASI) score from baseline at the end of treatment (EOT). Secondary efficacy end points included change from baseline in the pruritus numerical rating scale (NRS) score. RESULTS: In total, 327 patients were enrolled. At EOT, the least-squares mean percentage changes from baseline in mEASI score for JTE-052 at 0·25%, 0·5%, 1% and 3% and the vehicle ointment were -41·7%, -57·1%, -54·9%, -72·9% and -12·2%, respectively. All JTE-052 groups showed significant reductions of mEASI score vs. the vehicle group (P < 0·001 for all). In the tacrolimus group, the mean percentage change in mEASI score was -62·0%. The JTE-052 groups also showed significant improvement in other parameters; notably, the pruritus NRS score was reduced as early as day 1 night-time. JTE-052 ointment at doses up to 3% was safe and well tolerated. CONCLUSIONS: Topical JTE-052 markedly and rapidly improved clinical signs and symptoms in Japanese adult patients with moderate-to-severe AD, with a favourable safety profile. The study results indicate that topical JTE-052 is a promising therapeutic option for AD. The trial registration number is JapicCTI-152887.

Safety and efficacy of guselkumab in Japanese patients with moderate-to-severe plaque psoriasis: a randomized, placebo-controlled, ascending-dose study.

BACKGROUND: The interleukin (IL)-23/IL-17 pathway is central in the pathogenesis of psoriasis. The favourable efficacy and safety of guselkumab, an IL-23-specific monoclonal antibody, has been demonstrated in global phase III studies of plaque psoriasis. OBJECTIVES: To evaluate the safety, efficacy and pharmacokinetics of single-dose subcutaneous guselkumab in Japanese patients with moderate-to-severe plaque psoriasis. METHODS: Patients with ≥ 10% of total body surface area involvement and a Psoriasis Area and Severity Index (PASI) ≥ 12 were randomized (5 : 1) to receive guselkumab or placebo in four cohorts of this double-blind, placebo-controlled, single ascending-dose, single-centre study. Safety, pharmacokinetics and clinical response were monitored at baseline and specific time points over a 24-week follow-up period. RESULTS: To week 24, 55% (11/20) of patients in the guselkumab group and 50% (2/4) in the placebo group experienced ≥1 adverse event (AE). No deaths, serious AEs or AEs leading to treatment discontinuation were reported. Maximum clinical response was seen at week 16 with PASI 75 (≥ 75% improvement from baseline PASI) response in two of five (10 mg), four of five (30 mg and 300 mg) and three of five (100 mg) patients; and PASI 90 (≥ 90% improvement from baseline PASI) in zero of five (10 mg), three of five (30 mg), two of five (100 mg) and three of five (300 mg) patients. Mean maximum serum concentration (Cmax ) and area under the curve from time zero to infinity values increased in a dose-proportional manner with a mean terminal half-life of 15·6-17·6 days and median time to reach Cmax of 4-6 days. CONCLUSIONS: Guselkumab was generally well-tolerated and exhibited sustained high levels of clinical response in Japanese patients with moderate-to-severe psoriasis.

The first trial of CIM331, a humanized antihuman interleukin-31 receptor A antibody, in healthy volunteers and patients with atopic dermatitis to evaluate safety, tolerability and pharmacokinetics of a single dose in a randomized, double-blind, placebo-controlled study.

BACKGROUND: The cytokine interleukin-31 (IL-31) is considered to be responsible for the development of pruritus in humans. At present, no available evidence has been provided on the safety and efficacy of blocking the IL-31 signal in humans for the amelioration of pruritus in atopic dermatitis (AD). CIM331 is a humanized antihuman IL-31 receptor A (IL-31RA) monoclonal antibody, which binds to IL-31RA to inhibit subsequent IL-31 signalling. OBJECTIVES: To assess the tolerability, safety, pharmacokinetics and preliminary efficacy of CIM331 in healthy Japanese and white volunteers, and Japanese patients with AD. METHODS: In this randomized, double-blind, placebo-controlled phase I/Ib study, CIM331 was administered in a single subcutaneous dose. The primary outcomes were safety and tolerability; the exploratory analysis was efficacy. RESULTS: No deaths, serious adverse events (AEs) or discontinuations due to AEs were reported in any part of the study. No dose-dependent increase in the incidence of AEs occurred in any part of the study. In healthy volunteers, all AEs occurred once in the placebo groups, and increased creatine phosphokinase was more common in the CIM331 groups. In patients with AD, CIM331 reduced pruritus visual analogue scale score to about -50% at week 4 with CIM331 compared with -20% with placebo. CIM331 increased sleep efficiency and decreased the use of hydrocortisone butyrate. CONCLUSIONS: A single subcutaneous administration of CIM331 was well tolerated in healthy volunteers and patients with AD. It decreased pruritus, sleep disturbance and topical use of hydrocortisone. CIM331 may become a novel therapeutic option for AD by inhibiting IL-31.

An unusual case of nerve root compression by intradiscal gas pseudocyst of the lumbar spine.

An Intradiscal gas collection, referred to as the vacuum disc phenomenon (VDP) is a relatively common finding on radiographic studies of the lumbar spine, whereas gas-containing lumbar disc hernia is rarely observed. We report a case of a patient with left leg pain, provoked by a radiographically and surgically documented L4-5 gas containing disc hernia.

Phospholipase A2 activity modulates "ischemic effect" in pig skin.

The level of cyclic AMP in the epidermis rapidly increase within 15 min after separation from the in vivo condition. This phenomenon is the so-called "ischemic effect." In order to elucidate the possible mechanism of the ischemic effect, the effects of melittin and mepacrine on the ischemic condition of the skin were studied. Melittin, a stimulator of phospholipase A2, lessened the increase of cyclic AMP, while mepacrine, an inhibitor of phospholipase A2, potentiated the increase of cyclic AMP during the ischemic condition. The overall results suggest that phospholipase A2 may play an important role in the induction of the ischemic condition through membrane alteration.

Ornithine decarboxylase activity is inhibited by epidermal polyamine-dependent protein kinase-mediated phosphorylation.

Polyamine-dependent protein kinase in cytosol of pig epidermal cells was extracted. The fraction containing this enzyme exhibited multiple polypeptide bands on polyacrylamide gel electrophoresis, including 4 major polypeptide bands and several minor polypeptide bands. A 80 kilodalton (KD) polypeptide, one of the minor polypeptide bands, was phosphorylated by polyamine-dependent protein kinase. Authentic ornithine decarboxylase (ODC) exogenously added was separated into 2 subunits (80 KD and 40 KD) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and a 80 KD polypeptide was also phosphorylated by polyamine-dependent protein kinase. A 80 KD polypeptide of ODC comigrated with the polypeptide of cytosol which was phosphorylated by polyamine-dependent protein kinase. Kinetic study revealed that the ODC activity decreased as ODC was phosphorylated. Therefore, ODC activity was inhibited by epidermal polyamine-dependent protein kinase-mediated phosphorylation. The overall results indicate that the rapid turnover of ODC might be regulated by a phosphorylation-dephosphorylation reaction without new protein synthesis.

A novel synthetic vitamin A-like compound (a polyprenoic acid derivative, E-5166) inhibits the release of arachidonic acid stimulated by epidermal growth factor.

Little is known about the mechanisms of anti-inflammatory activity of retinoids. A new synthetic vitamin A-like compound (polyprenoic acid derivative, E-5166) has a strong in vitro binding affinity to intracellular binding proteins for acidic retinoids. In order to elucidate the anti-inflammatory activity of E-5166, we studied the effect of E-5166 on the epidermal growth factor (EGF)-stimulated arachidonic acid (AA) release of pig epidermis. E-5166 significantly inhibited the EGF-stimulated AA release and this inhibitory effect of E-5166 required a longer incubation than hydrocortisone did. Furthermore, E-5166 inhibited the EGF-stimulated phosphatidylinositol (PI) turnover of pig epidermis. These results indicate that E-5166 inhibited the EGF-stimulated AA release through the inhibition of the EGF-stimulated PI turnover.

Activation of cAMP-dependent protein kinase in epidermis by the compounds which increase epidermal cAMP.

Pig epidermal slices were incubated with various compounds which increased epidermal cAMP (adenosine 3',5'-monophosphate), and the change in cAMP-dependent protein kinase activity ratio was studied by the method of Cherrington et al (J Biol Chem 251:5209-5218, 1976) with modification. Epinephrine (5 x 10(-5) M), histamine (10(-4) M) and adenosine (10(-3) M), potent agonists of epidermal adenyl cyclase, fully activated the protein kinase (PK) during an incubation of 30 to 45 seconds, that was much shorter than that required for maximal cAMP accumulation under the same conditions (5 min). With such a brief stimulus, the epidermal cAMP-PK system did not become refractory and responded to repeated stimuli. Prostaglandin E2 (PGE2) and isobuthylmethylxanthine (IBMX) and ethanol only partially activated the enzyme. Prostaglandin F2 alpha (PGF2 alpha) and theophylline which were much less effective in increasing epidermal cAMP, activated the enzyme to the same extent as PGE2 and IBMX respectively. These results suggest that protein kinase activation takes place in response to a cAMP increase in small locus of the cell. Such an increase in cAMP can be very small or even not measurable when measured as total cAMP in the tissue homogenate. Also, increases above this level may not be physiologic. It is concluded that measurement of cAMP-dependent protein kinase activity ratio is a more direct and more sensitive way to study the effect of compounds which act through cAMP mediated mechanisms.

Epidermal cyclic GMP is increased in psoriasis lesions.

Cyclic GMP levels in epidermis of normal subjects and of psoriatic patients were measured with a highly sensitive radioimmunoassay method. Technical improvements for the assay are 2-fold: (1) skin samples were frozen in vivo before biopsy and local injection of any anesthetic was avoided to overcome ischemia effect which could lower cyclic GMP artificially; (2) epidermis was microdissected to avoid contamination of dermis and keratin layers. The results show that on a per mg tissue dry weight basis the cyclic GMP levels are about 200 fmol in the involved lesional epidermis and 70 fmol in the uninvolved or normal epidermis. Similarly increases in the cyclic GMP levels in the lesional epidermis are observed when the data are expressed either on a DNA or protein basis. The cyclic GMP level in normal epidermis from nonpsoriatic subjects is the same as that in the uninvolved epidermis of psoriasis patients.

Epidermal growth factor stimulates release of arachidonic acid in pig epidermis.

Epidermal growth factor (EGF) at physiologic concentrations (0.001-0.1 microgram/ml) stimulated the release of [14C] arachidonic acid [14C-AA] from pig epidermis. Although EGF stimulated the release of AA in the absence of exogenously added calcium to some extent, the addition of calcium (0.3-1.2 mM) significantly potentiated the release of AA stimulated by EGF. Ionophore A23187, which is known to stimulate phospholipase A2 activity by opening the calcium gates, potentiated the EGF-stimulated release of AA. The stimulatory effect of EGF was partially inhibited by the addition of mepacrine (70% inhibition at 10 microM) and by the pretreatment of hydrocortisone (60% inhibition at 1.0 microM). The loss of 14C-labeled phospholipids in pig epidermis was mainly due to the degradation of 14C-labeled phosphatidylcholine. Present results and recent reports by other workers suggest that EGF stimulates phospholipase A2 activity and result in the increased release of AA.

Epidermal growth factor stimulates tyrosine phosphorylation of pig epidermal fibrous keratin.

Epidermal growth factor (EGF) stimulated phosphorylation of pig epidermal proteins, one of which was pig epidermal keratin. In order to further characterize phosphorylated proteins and specify the EGF-dependent protein phosphorylation, we attempted to identify phosphorylated keratin proteins and to analyze phosphorylated phosphoamino acids of keratin proteins stimulated by EGF. Four major polypeptide bands of pig epidermal keratin were immunoprecipitated by antihuman callus keratin antibody which reacted with fine networks of fibrous keratin of pig epidermal cells grown in vitro. Four major polypeptide bands were greatly phosphorylated by EGF in a dose-dependent manner. The analysis of phosphorylated phosphoamino acids revealed that EGF stimulated tyrosine phosphorylation of pig epidermal fibrous keratin.

"Leaky" epidermal cells contain a complete receptor-mediated adenylate cyclase system with an accessible GTP regulatory protein.

Hormone sensitivity to epinephrine or histamine of the adenylate cyclase system in pig skin is very labile to homogenization. We have developed a new adenylate cyclase receptor-mediated assay system with trypsinized epidermal cells which are treated with hypotonic shock. This new assay system maintained the hormonal sensitivity, as both epinephrine and histamine clearly stimulated cyclic AMP production. Moreover, the Ka for each hormone on this system was similar to that obtained from the floating pig skin slice system. Receptor-adenylate cyclase unit (coupling) in this assay system is therefore preserved as it occurs in intact tissue or cells. Because of the "leaky" nature of our preparation, phosphorylated compounds such as GTP and its analogue and NaF can penetrate the cell membrane and stimulate cyclic AMP production. In this system refractoriness is still maintained to subsequent stimulation by a receptor activator, and cholera toxin can be shown to dramatically increase the activity of GTP on the GTP binding protein, presumably by preventing GTP hydrolysis.

Reversal of beta-agonist-induced refractoriness in skin by tetracaine and mepacrine.

We previously reported that in skin slices stimulated by a beta-adrenergic agonist, the intracellular cyclic AMP level increased transiently. The level returned to a low steady state in 20-30 min and further stimulation by the agonist did not increase the cyclic AMP level. This state of "refractoriness" was found to be specific to the initial stimulator, i.e., histamine but not epinephrine could restimulate the cyclic AMP system after an initial exposure to epinephrine (Biochim Biophys Acta 497:428-436, 1977). We now report that incubation of skin with mepacrine or tetracaine after beta-adrenergic stimulation caused partial recovery from the refractoriness. Neither the simultaneous incubation of skin with epinephrine plus mepacrine (or tetracaine) nor preincubation of skin with mepacrine (or tetracaine) before the beta-adrenergic stimulation prevented the development of the refractoriness. Mepacrine inhibited the skin adenylate cyclase catalytic (or the complex of GTP-regulatory protein and catalytic) unit. The available data suggest that mepacrine and tetracaine interacted with the agonist-receptor complex at the cell membrane.

Cyclic AMP-dependent protein kinase isozymes of pig skin and human skin from normal and psoriatic subjects.

Cyclic AMP-dependent protein kinase isozymes of pig and human skin (epidermis) were separated by DEAE-cellulose column chromatography after micromodification for small biopsy samples. Clear-cut separations of type I and type II isozymes, which were of about equal amounts, could be obtained only when the ischemia effect was avoided by in vivo freezing of skin and homogenization for less than 10 s. Intradermal injections of epinephrine caused dose-dependent activation of type I isozyme, but not of type II. Injections of other skin adenylate cyclase stimulators such as histamine, adenosine, and prostaglandin E2 elevated the local cyclic AMP levels to not more than 5 pmol/mg protein and also stimulated only the type I isozyme. Incubation of keratome-sliced pig skin under various conditions caused both activation by dissociation and inactivation by reassociation of the subunits, which appeared to be dependent on the cyclic AMP content. Epinephrine added to the incubation medium led to complete activation of both type I and type II isozymes (the intraepidermal cyclic AMP contents ranged from 20-50 pmol/mg protein). The isozymes of normal skin and involved skin of psoriatics showed identical peaks of type I and type II isozymes of equal amounts. The data indicate that protein kinase in the involved skin is not in an activated (by cyclic AMP) state.

Phosphorylation of pig epidermal soluble protein by endogenous cAMP-dependent protein kinase.

The distribution of adenosine 3',5'-monophosphate (cAMP)-dependent protein kinase and its substrate proteins was analyzed using soluble and particulate fractions of pig epidermal homogenates. When histone was used as a substrate for this enzyme reaction, protein kinase activity was distributed almost equally between the soluble and particulate fractions. However, the effect of exogenously added cAMP was confined almost exclusively to the soluble enzyme. Endogenous protein phosphorylation in the absence of exogenous histone was higher in the particulate fraction than in the soluble fraction, but the stimulating effect of cAMP was observed only in the soluble fraction. These results indicate that cAMP-dependent protein kinase is predominantly localized in the soluble fraction and phosphorylates soluble epidermal proteins. The particulate fraction contains protein kinase which is cAMP-independent and phosphorylates particulate-bound proteins as well as histone. Based on these observations, the soluble fraction was incubated with [gamma-32P]-ATP in the presence or absence of cAMP, and phosphorylated protein was analyzed by SDS disc- or slab-gel electrophoresis followed by autoradiography. Among many proteins whose phosphorylation was slightly increased by cAMP, a protein with Mr approximately 45,000 was found which was markedly phosphorylated in the presence of cAMP. Although this protein corresponds to one of the richest proteins in the epidermal soluble fraction, an important physiologic role for this phosphorylation has not been clarified.

Effects of trypsin on the cyclic AMP system of the pig skin.

Trypsin increased cyclic AMP levels of the pig skin. This effect was markedly potentiated by the cyclic nucleotide phosphodiesterase inhibitor theophylline. Without theophylline this trypsin-induced cyclic AMP accumulation was transient and the maximal accumulation was noted by 5 min. Soybean trypsin inhibitor inhibited this trypsin-induced cyclic AMP accumulation. After the trypsin treatment, marked acantholysis was noted histologically and the decreased responsiveness to other adenylate cyclase stimulators was seen. The decrease of the epinephrine response was most marked and that of histamine response was much less. Both low and high Km cyclic nucleotide phosphodiesterase activities were decreased by the trypsin treatment. However, at 5 min incubation time, when the increase in cyclic AMp level was most marked, the decrease in the phosphodiesterase activities was minimal. Trypsin seems to reveal its action through the proteolytic activation of adenylate cyclase system of the skin.

Measurement of adenosine 3',5'-monophosphate-dependent protein kinase and phosphorylase activities in in vivo conditions.

Microassay procedures for cAMP-dependent protein kinase and phosphorylase were developed which detected these activities in less than 25 micrograms of frozen-dried epidermis from a punch biopsy of skin without homogenization. Using these procedures, the activation of cAMP-dependent protein kinase and phosphorylase by beta-adrenergic stimulation in mouse skin was studied in vivo. Cyclic AMP-dependent protein kinase was stimulated by isoproterenol and inhibited by propranolol. Isoproterenol stimulation also activated phosphorylase a in mouse skin. In normal epidermis and uninvolved and involved epidermis from psoriatic patients no significant differences were found in the activities of cAMP-dependent kinase and phosphorylase a. In all experiments we observed that the unstimulated activity ratios of phosphorylase a/total phosphorylase were around 20-30%; these values were much lower than those hitherto reported and show a preponderance of phosphorylase b rather than a. We suggest that in previous reports where phosphorylase a domination was found, phosphorylase b to a activation occurred during homogenization. The data also suggest that in the steady state no obvious defect in basic activities of cAMP-dependent protein kinase and phosphorylase is observed in psoriatic skin.

Type-II collagen gene expression is transiently upregulated in experimentally induced degeneration of rabbit intervertebral disc.

To clarify phenotypic alterations of intervertebral disc cells during the repair process, we cloned partial type-II collagen cDNA from rabbits and analyzed the level of expression of type-II collagen mRNA in disc degeneration. An animal model was created by surgical denucleation of rabbit intervertebral discs through an extraperitoneal approach. Eight animals each from an experimental and a control group were killed at 2, 4, 8, or 16 weeks postoperatively, and the disc samples were used for this study. Round chondrocyte-like cells that filled the herniated space showed intense signal of type-II collagen mRNA and significant pericellular immunostaining of type-II collagen but no clear staining of type-I collagen. Northern blot analysis revealed that the expression of type-II collagen mRNA of the repair disc cells was transiently increased at 4 weeks postoperatively. The cells were able to change their morphology in response to mechanical stimulation by surgical denucleation and to induce a significant increase in the gene expression of type-II collagen at an early phase of disc degeneration. The present results indicate the transient enhancement of repair activity in the degenerative process of injured fibrocartilage.