First-in-human study demonstrating the safety and clinical efficacy of novel anti-IL-17A monoclonal antibody CJM112 in moderate to severe plaque psoriasis

Background and objective

Anti‐IL‐17A IgG/κ monoclonal antibody CJM112 binds both IL‐17A and IL‐17AF. The purpose of this First‐in‐Human study was to assess CJM112 effects on safety and efficacy in patients with moderate to severe plaque psoriasis.

Methods

This study had two parts: single ascending doses of 5–450 mg subcutaneous (s.c.) CJM112 (SAD) and multi‐dose parallel groups of CJM112 15 mg, 50 mg and 150 mg s.c. low frequency or high frequency (MD). SAD/MD were double‐blind, randomized and placebo‐controlled; MD also included a secukinumab 150 mg s.c. arm as an active comparator. Patients 18–65 years with moderate to severe psoriasis were included in this study. The efficacy outcome was the change in Psoriasis Area Severity Index (PASI) from baseline to Week 4 in the SAD part of the study, and from baseline to Week 12 in the MD part.

Results

96 patients were enrolled in this study (SAD, n = 42; MD, n = 54). In SAD, CJM112 doses from 15 mg and above demonstrated higher PASI responses compared with placebo at Week 12. CJM112 450 mg did not add further efficacy, but efficacy duration was prolonged compared with CJM112 150 mg. CJM112 MD resulted in a dose‐dependent decrease in PASI over time to Week 12. CJM112 150 mg high frequency did not exceed the effect of CJM112 150 mg low frequency and had similar efficacy to secukinumab 150 mg. The safety profile of CJM112 was as expected for an antibody targeting IL‐17A/IL‐17AF.

Conclusions

CJM112 had clinical efficacy in moderate to severe psoriasis and was generally safe and well tolerated in the doses tested. Additional neutralization of IL‐17AF did not translate to increased clinical efficacy compared with secukinumab.

The potential role of nerve growth factor, brain-derived neurotrophic factor and neurotrophin-3 in avian cochlear and vestibular ganglia development

The role of the nerve growth factor family of neurotrophins in the development of cochlear and vestibular ganglia is unclear. In order to predict the potential importance of nerve growth factor, brain-derived neurotrophic factor or neurotrophin-3, we examined the expression of neurotrophin mRNA and full-length neurotrophin receptor mRNA by in-situ hybridization and reverse transcription-polymerase chain reaction, as well as whether high affinity 125I-nerve growth factor binding was present, in cochlear and vestibular ganglia of the quail at several stages of development (stages 26, 31 and 36). Nerve growth factor, brain-derived neurotrophic factor and neurotrophin-3 mRNA was detected at all ages examined, suggesting that these neurotrophins may serve an autocrine or paracrine function, especially prior to target contact. In addition, we found full-length trkA and trkC mRNA was expressed, the products of which are the functional neuronal receptors for nerve growth factor and neurotrophin-3, respectively. Although full-length trkA mRNA was found, physiologically important high affinity 125I-nerve growth factor binding was not detected. Since nerve growth factor's effects on survival and neurite outgrowth are mediated through high affinity binding, nerve growth factor may serve an as yet unidentified role in this system. Full-length trkB mRNA, the product of which is the functional neuronal receptor for brain-derived neurotrophic factor, was not detected using reverse transcription-polymerase chain reaction, however, truncated (non-catalytic) trkB was present, at least in cochlear ganglia at stage 31. It is not known what function may be subserved by these truncated receptors.

Early embryonic quail dorsal root ganglia exhibit high affinity nerve growth factor binding and NGF responsiveness--absence of NGF receptors on migrating neural crest cells

Dorsal root ganglia (DRG) midway through development require nerve growth factor (NGF) for survival and differentiation. These studies investigated when avian neural crest cells or DRG first exhibit high affinity NGF receptors in situ, and whether early embryonic cells expressing high affinity NGF receptors are responsive to NGF. Unfixed cryostat sections of quail embryos were exposed to varying concentrations of [125I]NGF to distinguish between high and low affinity binding. Radioautography revealed an absence of [125I]NGF binding on migrating neural crest cells in situ. Both high and low affinity NGF receptors were first detected in differentiating DRG at E3.5 (stage 23). The presence of high affinity receptors was additionally confirmed by identification of a high molecular weight complex on radioautographs of gels following cross-linking of [125I]NGF to dissociated DRG. The presence of high affinity NGF receptors in E3.5 DRG was unexpected since DRG have been reported to be unresponsive to NGF prior to the midpoint of development. Exposure of E3.5 DRG neuron-enriched cultures to exogenous NGF resulted in approximately 30% more neurons after 24 h in vitro. The effect of NGF was blocked by anti-NGF and was shown to be dose dependent. It remains to be determined whether the increase in cell number is due to a survival or mitogenic effect.

[New 5'-phosphonates, modified through the nucleoside sugar residue, as inhibitors of HIV replication]

A number of nucleoside 5'-phosphonates and nucleoside 5'-methylphosphonates were synthesised, to study their ability to inhibit reproduction of HIV-1. Three compounds, 5'-hydrogen phosphonates of 3'-azido-2',3'-dideoxythymidine (AZT-HP, IVc), 3'-fluoro-2',3'-dideoxythymidine (FLT-HP, IVa) and 2',3'-dideoxyadenosine (ddA-HP, I), exhibit potent anti-HIV-1 activity with selectivity indices similar to or better of those of their parent nucleosides.

gamma-Aminobutyric acidA receptor regulation in culture: altered allosteric interactions following prolonged exposure to benzodiazepines, barbiturates, and methylxanthines

In previous reports, we have described the use of primary neuronal cultures derived from chick brain to study the regulation of the gamma-aminobutyric acidA (GABAA) receptor complex. Chronic exposure of cultures to GABA, benzodiazepines, or methylxanthines results in decreased enhancement of [3H]flunitrazepam binding by GABA, consistent with an allosteric uncoupling of GABA and benzodiazepine recognition sites of the GABAA receptor. In the present communication, we extend our studies of the pharmacology of benzodiazepine- and methylxanthine-induced uncoupling of GABA/benzodiazepine recognition site interactions and present evidence to show that certain barbiturates (barbital and pentobarbital) also induce uncoupling. Chronic exposure to flurazepam (a high efficacy benzodiazepine) elicits no change in the number of benzodiazepine binding sites or the affinity of benzodiazepine binding in the absence of GABA. Whereas flurazepam and theophylline decrease coupling, Ro15-1788 (a low efficacy benzodiazepine) inhibits flurazepam-induced but not theophylline-induced uncoupling, suggesting that theophylline and flurazepam act through separate receptors. Flurazepam-induced uncoupling is not prevented by SR-95531 or picrotoxin (specific inhibitors of GABA action) and, therefore, is not an indirect effect mediated by endogenous GABA. The onset of flurazepam-induced uncoupling (EC50 approximately 1 microM) exhibits a t 1/2 of about 18 hr, in general agreement with the half-time for receptor turnover. Uncoupling is reversible following washout and recovery at 37 degrees. These results are discussed in terms of mechanisms of GABAA receptor regulation in response to chronic exposure to functionally homologous or heterologous ligands.

Chronic agonist exposure induces down-regulation and allosteric uncoupling of the gamma-aminobutyric acid/benzodiazepine receptor complex

Using [3H]flunitrazepam as a probe for the benzodiazepine-sensitive modulator site located on the gamma-aminobutyric acid (GABA)A receptor complex, we have investigated the cellular regulation of the GABAA receptor in neuronal cultures derived from embryonic chick brain. Treatment of cultures with 1 mM GABA for 48 hr causes a reversible 35% decrease in the number of [3H]flunitrazepam binding sites with no change in affinity. The EC50 for chronic GABA-induced down-regulation is 94 microM and the half-time is 25 hr. The effect of GABA is blocked by SR-95531, a GABAA receptor antagonist, and mimicked by muscimol but not baclofen. Consistent with the decrease in [3H]flunitrazepam binding, chronic GABA exposure causes a 43% decrease in the binding of [35S]t-butylbicyclophosphorothionate, a ligand for the receptor-associated chloride ionophore. In addition to chronic GABA-induced down-regulation, allosteric interactions between GABA and benzodiazepine recognition sites are uncoupled by 34%. The half-time and pharmacology for chronic GABA-induced uncoupling is indistinguishable from that for GABA-induced down-regulation, consistent with the hypothesis that the action of GABA at a common site induces both down-regulation and uncoupling.

Gonadotropin responses to low dose pulsatile administration of GnRH in a case of anosmia with hypogonadotropic hypogonadism associated with gonadal dysgenesis 47 XXY

A 25 year old man presented hypogonadotropic hypogonadism with complete anosmia (Kallman's syndrome). His chromosomic type was 47 XXY (Klinefelter's syndrome). Clinical findings were: height 183 cm, weight 62 kg, increased length of lower limbs, P2-A2 pilosity and micropenis. Only a left testis was present (1.5-1.5 cm). Bone age was 15. Testicular biopsy showed that the signs were more related to the gonadotropic deficit than to the gonadal dysgenesis; tubular hyalinization was not observed. Plasma levels of testosterone and oestradiol were very low. Plasma gonadotropin levels were below normal ranges and did not respond to an infusion test of GnRH. GnRH was administered iv every 90 min for 3 weeks by an auto syringe infusion pump and induced a pulsatile response of FSH and LH. Plasma levels of testosterone and oestradiol were unaffected. It may be concluded that the results of pulsatile injection of GnRH confirmed in this patient a unique association of Kallmann's syndrome with complete 47 XXY Klinefelter's syndrome.

[Erdheim-Chester disease. The multiviceral form presenting as exophthalmos]

Erdheim-Chester disease is a rare visceral xantho-granulomatosis, the 17th case of which is reported here. The initial symptom, bilateral exophthalmos, was uncommon. The picture was completed by a retroperitoneal xanthogranuloma and by bilateral and symmetrical osteosclerosis of the long bones. The lack of X-bodies at electron microscopy differentiated the disease from Hand-Schüller-Christian disease. The patient's condition improved with chemotherapy (vinblastine and doxorubicin) combined with corticosteroid therapy. After a 5-month remission period, he died of an intercurrent infection. No autopsy was performed.

Effects of thyrotrophin-releasing hormone on plasma catecholamine levels in acromegalics

Plasma catecholamines assayed by a double isotope radio enzymatic method were studied in the basal state and during a thyrotrophin-releasing hormone (TRH)-test in 7 acromegalics, divided into 2 groups: active and non-active acromegalics, according to clinical and biological criteria. Basal plasma norepinephrine levels were significantly increased in the active group 648 +/- 22 pg/ml (P less than 0.001) and were in the normal range in the non-active group 439 +/- 26 pg/ml. Basal plasma epinephrine values were not significantly different in the 2 groups 59 +/- 15 pg/ml vs 34 +/- 7 pg/ml. During a TRH-test, norepinephrine levels remained elevated (P less than 0.001) in the active group, and the difference between the 2 groups was enhanced during the test. On the other hand the 2 patients who responded to TRH demonstrated an increase of norepinephrine levels. Our results suggest that TRH may stimulate norepinephrine release in acromegalics with an active response to TRH.

Immunoreactive alpha-MSH and ACTH levels in rat plasma and pituitary

A radioimmunoassay is described for the measurement of alpha-melanocyte-stimulating hormone (alpha-MSH). The antibody was produced in rabbits by immunization with alpha-MSH coupled to bovine serum albumin with carbodiimide. The antibody did not react significantly with ACTH, beta-MSH, or 6 fragments of ACTH. The sensitivity and reliability of the assay were improved by employing a simple plasma extraction procedure. When applied to a 2 ml plasma sample, the detection limit of the radioimmunoassay was 6 pg/ml. ACTH was measured with a sensitive and specific radioimmunoassay previously described for humans and adapted for the rat. The anti-ACTH serum cross-reacted with the biologically active portion of alpha-p ACTH and not with alpha-MSH, beta-MSH or the alpha-p 17-39 and alpha-p 25-39 fragments of ACTH. The detection limit was 20 pg/ml. Plasma and pituitary alpha-MSH and ACTH had the same immunoreactivity as synthetic alpha-MSH and ACTH. alpha-MSH and ACTH contents of the rat neurointermediate lobe were 1398 +/- 360 (SE) ng and 28.2 +/- 2.9 ng, respectively, while in the anterior lobe they were 102 +/- 31 ng and 551 +/- 36 ng, respectively. The plasma alpha-MSH concentration at 8 AM in male rats was 64 +/- 8 pg/ml when the plasma ACTH concentration was 92 +/- 15 pg/ml. Over a 24-hour period two peaks of plasma alpha-MSH were observed, one at 4 AM (142 +/- 35 pg/ml) and the other at 4 PM (139 +/- 26 pg/ml). Plasma ACTH was higher at noon (151 +/- 43 pg/ml) and 4 PM (130 +/- 48 pg/ml). Short-term exposure to ether induced a transient increase in alpha-MSH level 5 min later and a rapid return to normal levels. Plasma ACTH increased significantly 2.5 min after the onset of ether stress and remained high for 30 min. Two hours' exposure to ether did not change plasma alpha-MSH, although a 3-fold increase in plasma ACTH was observed. Haloperidol injection was followed by a large increase in plasma alpha-MSH, whereas ACTH levels increased similarly after saline and Haloperidol injection. Corticoid administration reduced ACTH, but not alpha-MSH. Three weeks after adrenalectomy, alpha-MSH levels had not changed but ACTH levels had increased ten-fold. These data indicate that alpha-MSH is secreted in the rat, and that the regulation of its secretion is different from that of ACTH.