Discovery of GLPG1972/S201086, a Potent, Selective, and Orally Bioavailable ADAMTS-5 Inhibitor for the Treatment of Osteoarthritis

There are currently no approved disease-modifying osteoarthritis (OA) drugs (DMOADs). The aggrecanase ADAMTS-5 is key in the degradation of human aggrecan (AGC), a component of cartilage. Therefore, ADAMTS-5 is a promising target for the identification of DMOADs. We describe the discovery of GLPG1972/S201086, a potent and selective ADAMTS-5 inhibitor obtained by optimization of a promising hydantoin series following an HTS. Biochemical activity against rat and human ADAMTS-5 was assessed via a fluorescence-based assay. ADAMTS-5 inhibitory activity was confirmed with human aggrecan using an AGC ELISA. The most promising compounds were selected based on reduction of glycosaminoglycan release after interleukin-1 stimulation in mouse cartilage explants and led to the discovery of GLPG1972/S201086. The anticatabolic activity was confirmed in mouse cartilage explants (IC₅₀ < 1.5 μM). The cocrystal structure of GLPG1972/S201086 with human recombinant ADAMTS-5 is discussed. GLPG1972/S201086 has been investigated in a phase 2 clinical study in patients with knee OA (NCT03595618).

Discovery of 2-[[2-Ethyl-6-[4-[2-(3-hydroxyazetidin-1-yl)-2-oxoethyl]piperazin-1-yl]-8-methylimidazo[1,2-a]pyridin-3-yl]methylamino]-4-(4-fluorophenyl)thiazole-5-carbonitrile (GLPG1690), a First-in-Class Autotaxin Inhibitor Undergoing Clinical Evaluation for the Treatment of Idiopathic Pulmonary Fibrosis

Autotaxin is a circulating enzyme with a major role in the production of lysophosphatic acid (LPA) species in blood. A role for the autotaxin/LPA axis has been suggested in many disease areas including pulmonary fibrosis. Structural modifications of the known autotaxin inhibitor lead compound 1, to attenuate hERG inhibition, remove CYP3A4 time-dependent inhibition, and improve pharmacokinetic properties, led to the identification of clinical candidate GLPG1690 (11). Compound 11 was able to cause a sustained reduction of LPA levels in plasma in vivo and was shown to be efficacious in a bleomycin-induced pulmonary fibrosis model in mice and in reducing extracellular matrix deposition in the lung while also reducing LPA 18:2 content in bronchoalveolar lavage fluid. Compound 11 is currently being evaluated in an exploratory phase 2a study in idiopathic pulmonary fibrosis patients.

A TNF receptor loop peptide mimic blocks RANK ligand-induced signaling, bone resorption, and bone loss

Activating receptor activator of NF-kappaB (RANK) and TNF receptor (TNFR) promote osteoclast differentiation. A critical ligand contact site on the TNFR is partly conserved in RANK. Surface plasmon resonance studies showed that a peptide (WP9QY) that mimics this TNFR contact site and inhibits TNF-alpha-induced activity bound to RANK ligand (RANKL). Changing a single residue predicted to play an important role in the interaction reduced the binding significantly. WP9QY, but not the altered control peptide, inhibited the RANKL-induced activation of RANK-dependent signaling in RAW 264.7 cells but had no effect on M-CSF-induced activation of some of the same signaling events. WP9QY but not the control peptide also prevented RANKL-induced bone resorption and osteoclastogenesis, even when TNFRs were absent or blocked. In vivo, where both RANKL and TNF-alpha promote osteoclastogenesis, osteoclast activity, and bone loss, WP9QY prevented the increased osteoclastogenesis and bone loss induced in mice by ovariectomy or low dietary calcium, in the latter case in both wild-type and TNFR double-knockout mice. These results suggest that a peptide that mimics a TNFR ligand contact site blocks bone resorption by interfering with recruitment and activation of osteoclasts by both RANKL and TNF.

[Identification of the epidural space: usual practice among Spanish anesthesiologists]

OBJECTIVE

To determine what methods are habitually used by Spanish anesthesiologists to identify the epidural space.

MATERIAL AND METHODS

Spanish anesthesiologists were asked to fill in an Internet questionnaire about the methods they had learned during residency training for identifying the epidural space, the method they currently use most often, and the one they consider best for residents to learn during training.

RESULTS

Responses were received from 617 anesthesiologists. The techniques the respondents had learned during training were loss of resistance to air (LOR-A), 58.5%; LOR to saline (LOR-S), 31.9%; LOR and air bubble (LOR-B), 6.1%; and the hanging drop method, 2.4%. Those who had learned the LOR-A technique had changed in 14.2% of the cases, as had 28.4% of those who learned the LOR-S procedure. LOR-A is currently used by 59.2% of the respondents, LOR-S is used by 32.4%, and LOR-B by 6%. The respondents recommended that new residents physicians learn the LOR-A (48.5%) and LOR-S (37.8%) techniques. The LOR-B is recommended by 12.6% a much larger percentage of anesthesiologists than it is habitually used by. Of those who use the LORA technique habitually, 26.4% recommend that new residents use a different procedure.

CONCLUSIONS

The procedure used most often by Spanish anesthesiologists to identify the epidural space is the LOR-A technique; however, over a quarter of Spanish users of LOR-A do not recommend it.

[Analysis of bibliographic citations received by Spanish anesthesiologists for work indexed by Science Citation Index, 1988-2002]

OBJECTIVE

To analyze the international impact of articles published by authors in Spanish anesthesiology departments.

METHOD

Citable articles indexed by Science Citation Index between 1988 and 2002 and authored by members of Spanish departments of anesthesiology were considered. Citations were counted 2 years and 5 years after publication. Authors and institutions were ranked according to number of citations received. We also determined the journals Spanish anesthesiologists most often chose for publishing their work.

RESULTS

Of the 322 citable articles identified, 61.8% were cited in the 2 years following publication (total 587 citations), and 79.5% were cited within 5 years (total 1472 citations). The most frequently cited articles received 17 citations in 2 years and 45 in 5 years after publication. Articles from the Department of Anesthesiology of Hospital Clinic i Provincial of Barcelona received the largest number of citations (333 citations in 5 years). The author with the highest rate of citations received 11.57 per article. The author with the largest number of citations received 86. Anesthesia & Analgesia was the journal publishing the largest number of articles by Spanish anesthesiologists (35 articles).

CONCLUSION

This citation analysis shows the international impact of publications by Spanish anesthesiologists.

Effects of SK&F 86002 on cytokine-stimulated IL6 production in cultured neonatal mouse calvaria and SaOS2 osteoblastic cells: the role of prostaglandins and other mechanisms of action

The cytokine-suppressant anti-inflammatory drug (CSAID) SK&F 86002 inhibits bone resorption in vitro and this effect cannot be totally explained by its inhibition of IL 1 beta and TNF alpha release. IL6 is another cytokine important in the mechanisms of bone resorption and could be a target for the actions of SK&F 86002. IL6 release and resorption (45Ca release) were induced by IL 1 beta in neonatal mouse calvaria bones in culture. Both indomethacin (5 x 10(-8)-5 x 10(-6) M) and SK&F 86002 (5 x 10(-7)-10(-5) M) markedly inhibited the IL6 release and totally inhibited resorption at all concentrations tested. This may result from inhibition of prostaglandin production by both compounds. In human osteoblastic cells (SaOS2) both basal and TNF alpha-stimulated IL6 production were inhibited in a concentration-related manner by SK&F 86002 but not by indomethacin. The effect of SK&F 86002 was greatest in 6 h cultures where relatively low levels of IL6 are produced and progressively less in 24 and 48 h cultures which produce higher levels of IL6. This is unlikely to be an indirect effect via inhibition of IL 1 beta production as no IL 1 beta (< 0.3 pg/ml) was detected in non-stimulated or stimulated culture supernatants. Therefore, SK&F 86002 may inhibit IL6 production in osteoblastic cells via a more direct mechanism, possibly involving inhibition of the p38 MAP kinase, the mechanism proposed for its inhibition of IL 1 beta and TNF alpha release.