A proof-of-concept open-label clinical trial of spleen tyrosine kinase antagonism using fostamatinib in moderate-to-severe hidradenitis suppurativa.

BACKGROUND: Hidradenitis suppurativa (HS) is an autoinflammatory disorder of keratinization with a prominence of B cells and plasma cells. Fostamatinib is a spleen tyrosine kinase inhibitor targeting B cells and plasma cells. OBJECTIVES: To assess the safety, tolerability, and clinical response at week 4 and week 12 of fostamatinib in moderate-to-severe HS. METHODS: Twenty participants were administered fostamatinib 100 mg twice a day for 4 weeks, escalating to 150 mg twice a day thereafter until week 12. Participants were assessed for adverse events and clinical response assessed by HiSCR (Hidradenitis Suppurativa Clinical Response Score) and IHS4 (International Hidradenitis Suppurativa Severity Score) as well as other outcomes including DLQI (Dermatology Life Quality Index), visual analog scale, and physician global assessment. RESULTS: All 20 participants completed the week 4 and week 12 endpoints. Fostamatinib was well tolerated in this cohort with no grade 2/3 adverse events reported. A total of 85% achieved HiSCR at week 4 and 85% at week 12. The greatest reduction in disease activity was seen at weeks 4/5 with worsening in a proportion of patients thereafter. Significant improvements were seen in pain, itch, and quality of life. CONCLUSIONS: Fostamatinib was well tolerated in this HS cohort with no serious adverse events and improvement in clinical outcomes. Targeting B cells/plasma cells may be a viable therapeutic strategy in HS and requires further exploration.

PAX-D: study protocol for a randomised placebo-controlled trial evaluating the efficacy and mechanism of pramipexole as add-on treatment for people with treatment resistant depression.

INTRODUCTION: Clinical depression is usually treated in primary care with psychological therapies and antidepressant medication. However, when patients do not respond to at least two or more antidepressants within a depressive episode, they are considered to have treatment resistant depression (TRD). Previous small randomised controlled trials suggested that pramipexole, a dopamine D2/3 receptor agonist, may be effective for treating patients with unipolar and bipolar depression as it is known to influence motivational drive and reward processing. PAX-D will compare the effects of pramipexole vs placebo when added to current antidepressant medication for people with TRD. Additionally, PAX-D will investigate the mechanistic effect of pramipexole on reward sensitivity using a probabilistic decision-making task. METHODS AND ANALYSIS: PAX-D will assess effectiveness in the short- term (during the first 12 weeks) and in the longer-term (48 weeks) in patients with TRD from the UK. The primary outcome will be change in self-reported depressive symptoms from baseline to week 12 post-randomisation measured using the Quick Inventory of Depressive Symptomatology Self-Report (QIDS-SR16). Performance on the decision-making task will be measured at week 0, week 2 and week 12. Secondary outcomes include anhedonia, anxiety and health economic measures including quality of life, capability, well-being and costs. PAX-D will also assess the adverse effects of pramipexole including impulse control difficulties. DISCUSSION: Pramipexole is a promising augmentation agent for TRD and may be a useful addition to existing treatment regimes. PAX-D will assess its effectiveness and test for a potential mechanism of action in patients with TRD. TRIAL REGISTRATION NUMBER: ISRCTN84666271.

Atropisomeric small molecule Bcl-2 ligands: determination of bioactive conformation.

The separation of atropisomeric conformers of 1,2,3,4-tetrahydroisoquinoline amide Bcl-2 ligands allowed the identification of the bioactive conformer which was subsequently confirmed by X-ray crystallography.

Tetrahydroisoquinoline amide substituted phenyl pyrazoles as selective Bcl-2 inhibitors.

Anti-apoptotic Bcl-2 protects cells from apoptosis by binding to pro-apoptotic members of the Bcl-2 family thereby playing a role in tumour survival in response to chemo- or radiation therapy. We describe a series of phenyl pyrazoles that have high affinity for Bcl-2 and rationalise the observed SAR by means of an X-ray crystal structure.