Effect of BI 1358894 on Cholecystokinin-Tetrapeptide (CCK-4)-Induced Anxiety, Panic Symptoms, and Stress Biomarkers: A Phase I Randomized Trial in Healthy Males

Property-Based Design of Xanthine Derivatives as Potent and Orally Available TRPC4/5 Inhibitors for Depression and Anxiety

Transient receptor potential canonical channels 4 and 5 (TRPC4/5) are nonselective cation channels involved in emotional regulation, positioning them to be promising targets for treating mental disorders such as anxiety and depression. HC-070, a potent TRPC4/5 inhibitor, exhibits significant anxiolytic and antidepressant effects in animal models, though its drug-like properties require optimization. In this study, we applied a property-based drug design (PBDD) approach to optimize HC-070, leading to the discovery of compound 32, which shows improved LipE and Fsp3 values, reduced hERG blocking activity, enhanced metabolic stability, increased aqueous solubility, and superior oral bioavailability. Oral administration of compound 32 in mouse models demonstrates anxiolytic and antidepressant efficacy comparable to fluoxetine. This study supports the therapeutic potential of TRPC4/5 inhibitors for mental disorders and identifies compound 32 as a promising candidate for further investigation. Furthermore, our work underscores the value of PBDD in optimizing lead compounds during drug discovery process.

Safety of BI 1358894 in patients with major depressive disorder: Results and learnings from a phase II randomized decentralized clinical trial

The feasibility of conducting a fully remote, interventional, phase II decentralized clinical trial (DCT) was investigated in major depressive disorder (MDD). Key learnings were collated to improve future DCTs. A double-blind, placebo-controlled, parallel-group, DCT enrolled adult MDD patients with inadequate response to first-line antidepressant monotherapy (ongoing ≥8 weeks) and a Montgomery-Åsberg Depression Rating Scale total score (MADRS) ≥22 at screening. Patients were randomized 1:1 to BI 1358894 125 mg or placebo daily for 6 weeks remotely. Safety parameters, primary end point (change from baseline in MADRS at Week 6), and patient experience were assessed. The DCT was considered feasible if the trial protocol could be successfully executed. Overall, DCT procedures were successfully executed per protocol. However, despite achieving a vast patient outreach, the trial was terminated early due to deficient enrollment. Of the 136 patients who consented for enrollment and underwent screening, 45 were randomized and 43 received treatment (BI 1358894, n = 20; placebo, n = 23); 97.7% of patients completed the trial. Patients had a mean (SD) age of 42.2 (13.1) years and most (83.7%) were female. Adverse events were reported by 86.0% of patients (BI 1358894, 90.0%; placebo, 82.6%). Most patients (88%) reported a positive experience with the DCT. Key learnings related to the impact of stringent eligibility criteria, recruitment optimization strategies, plus the benefits and limitations of digital technologies. A fully remote, interventional DCT was feasible in MDD, and was well perceived by trial participants. Learnings related to recruitment optimization and trial design should be considered for future interventional DCTs.

Transient receptor potential channels in viral infectious diseases: Biological characteristics and regulatory mechanisms

BACKGROUND

Viral infectious diseases have long posed a challenge to humanity. In recent decades, transient receptor potential (TRP) channels have emerged as newly investigated cation channels. Increasing evidence suggests that TRP channel-mediated Ca2+ homeostasis disruptions, along with associated pathological changes, are critical factors in the onset and progression of viral infectious diseases. However, the precise roles and mechanisms of TRP channels in these diseases remain to be systematically elucidated.

AIM OF REVIEW

The aim of this review is to systematically summarize recent advances in understanding TRP channels in viral infections, and based on current progress and challenges, propose future directions for research.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review summarizes the classification and biological functions of the TRP family, explores the mechanisms by which TRP channels contribute to viral infections, and highlights specific mechanisms at three levels: virus, host, and outcome. These include the direct role in viral biology and replication, the indirect role in host immunity and inflammation, and the resulting pathological changes. Additionally, we discuss the potential applications of the TRP family in the treatment of viral infectious diseases and propose future research directions.

TRPC4/5 inhibitors: Phase I results and proof of concept studies

Transient receptor potential canonical (TRPC) ion channels are expressed in areas of the brain responsible for processing emotion and mood and have been implicated in the pathophysiology of internalizing disorders such as major depressive disorder and anxiety disorders. This review outlines the rationale for targeting TRPC ion channels for drug development, with specific focus on TRPC4 and TRPC5. We provide preclinical evidence that the lack of TRPC4 and TRPC5 channels or its pharmacological inhibition attenuate fear and anxiety without impairing other behaviors in mice. We also report on clinical studies of BI 1358894, a small molecule inhibitor of TRPC4/5 ion channels, demonstrating reduced psychological and physiological responses to induced anxiety/panic-like symptoms in healthy volunteers. Furthermore, we highlight an imaging study that investigated the acute effects of BI 1358894 and showed reduced activation in several brain regions involved in emotional processing. We conclude that these findings demonstrate a critical role for TRPC4 and TRPC5 in emotional processing, even though it remains an open question if the biological signatures of TRPC4/5 inhibition reported here translate into clinical efficacy and indicate that a TRPC4/5 inhibitor might provide a more effective treatment of internalizing disorders.

Biochemical challenges for testing novel anti-panic drugs in humans

Current medications for panic disorder each carry significant limitations that indicate the need for novel anxiolytics. The high costs and low success rates of drug development demand that testing trials be efficient. Lab panicogenic challenges in humans allow for the rapid biochemical induction of panic symptoms and hence an efficient means of testing potential anti-panic drugs. This paper describes ideal characteristics of lab panicogens, reviews the validity and utility of various biochemical panicogenic agents, identifies key outcome measures for studies of novel anti-panic drugs, and makes broad recommendations for labs wishing to perform such studies. We conclude by presenting a four-tiered hierarchy of panicogens that matches each against ideal characteristics and reflects our recommendations for their laboratory use.

Safety, Tolerability, and Pharmacokinetics of Oral BI 1358894 in Healthy Japanese Male Volunteers

BACKGROUND AND OBJECTIVES: BI 1358894, a novel small-molecule inhibitor of transient receptor potential canonical ion channels, is under development for treatment of major depressive disorder. Phase I trials assessing the safety and pharmacokinetics of BI 1358894 in Caucasian male healthy volunteers (HVs) have been performed. This Phase I, double-blind, placebo-controlled, parallel-group trial assessed the safety, tolerability and pharmacokinetics of BI 1358894 in Japanese male HVs.

METHODS

Male HVs were randomized to receive oral BI 1358894 (n = 18) or placebo (n = 6) after a high-fat, high-calorie meal within three dose groups (50 mg, 100 mg, 200 mg), administered sequentially in dose-ascending order. The primary endpoint was number of HVs with drug-related adverse events (DRAEs). Secondary endpoints were the pharmacokinetic parameters of BI 1358894.

RESULTS

Overall, 24 male HVs entered the trial [mean (standard deviation) age: 30.0 (7.6) years]. DRAEs occurred in 3/18 HVs (BI 1358894 100 mg group: one HV experienced dizziness and headache; BI 1358894 200 mg group: one HV experienced headache, another reported sleep disorder). BI 1358894 exposure increased dose dependently and proportionally, peaking 4-6 h after administration before declining in a multiphasic manner with a terminal elimination half-life of ~70 h in the 50 mg and 100 mg dose groups, and 203 h in the 200 mg dose group.

CONCLUSION

BI 1358894 was well tolerated with a favorable pharmacokinetic profile in Japanese male HVs, similar to findings from a previous study in Caucasian male HVs.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03875001; 08-Mar-2019).

Targeting TRP channels for pain relief: A review of current evidence from bench to bedside

Several decades of research support the involvement of transient receptor potential (TRP) channels in nociception. Despite the disappointments of early TRPV1 antagonist programs, the TRP family remains a promising therapeutic target in pain disorders. High-dose capsaicin patches are already in clinical use to relieve neuropathic pain. At present, localized injections of the side-directed TRPV1 agonist capsaicin and resiniferatoxin are undergoing clinical trials in patients with osteoarthritis and bone cancer pain. TRPA1, TRPM3, and TRPC5 channels are also of significant interest. This review discusses the role of TRP channels in human pain conditions.

Cholecystokinin (CCK): a neuromodulator with therapeutic potential in Alzheimer's and Parkinson's disease

Cholecystokinin (CCK) is a neuropeptide modulating digestion, glucose levels, neurotransmitters and memory. Recent studies suggest that CCK exhibits neuroprotective effects in Alzheimer's disease (AD) and Parkinson's disease (PD). Thus, we review the physiological function and therapeutic potential of CCK. The neuropeptide facilitates hippocampal glutamate release and gates GABAergic basket cell activity, which improves declarative memory acquisition, but inhibits consolidation. Cortical CCK alters recognition memory and enhances audio-visual processing. By stimulating CCK-1 receptors (CCK-1Rs), sulphated CCK-8 elicits dopamine release in the substantia nigra and striatum. In the mesolimbic pathway, CCK release is triggered by dopamine and terminates reward responses via CCK-2Rs. Importantly, activation of hippocampal and nigral CCK-2Rs is neuroprotective by evoking AMPK activation, expression of mitochondrial fusion modulators and autophagy. Other benefits include vagus nerve/CCK-1R-mediated expression of brain-derived neurotrophic factor, intestinal protection and suppression of inflammation. We also discuss caveats and the therapeutic combination of CCK with other peptide hormones.