The Effect of Anti-Chemokine Oral Drug XC8 on Cough Triggered by The Agonists of TRPA1 But Not TRPV1 Channels in Guinea Pigs.

INTRODUCTION: Chronic cough heavily affects patients' quality of life, and there are no effective licensed therapies available. Cough is a complication of severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) infection, asthma, and other diseases. Patients with various diseases have a different profile of tussive responses to diverse cough triggers, thereby suggesting sundry mechanisms of neuronal dysfunctions. Previously, we demonstrated that the small molecule drug XC8 shows a clinical anti-asthmatic effect. The objective of the present study was to investigate the effect of XC8 on cough. METHODS: We studied the antitussive effect of XC8 on cough induced by agonists activating human transient receptor potential (TRP) cation channels TRPA1 or TRPV1 in guinea pigs. We checked the agonistic/antagonistic activity of XC8 on the human cation channels TRPA1, TRPV1, TRPM8, P2X purinoceptor 2 (P2X2), and human acid sensing ion channel 3 (hASIC3) in Fluorescent Imaging Plate Reader (FLIPR) assay. RESULTS: XC8 demonstrated clear antitussive activity and dose-dependently inhibited cough in guinea pigs induced by citric acid alone (up to 67.1%) or in combination with IFN-γ (up to 76.4%). XC8 suppressed cough reflexes induced by the repeated inhalation of citric acid (up to 80%) or by cinnamaldehyde (up to 60%). No activity of XC8 against cough evoked by capsaicin was revealed. No direct agonistic/antagonistic activity of XC8 on human TRPA1, TRPV1, TRPM8, P2X2, or hASIC3 was detected. CONCLUSIONS: XC8 acts against cough evoked by the activation of TRPA1 (citric acid/cinnamaldehyde) but not TRPV1 (capsaicin) channels. XC8 inhibits the cough reflex and suppresses the cough potentiation by IFN-γ. XC8 might be of significant therapeutic value for patients suffering from chronic cough associated with inflammation.

A Novel Oral Glutarimide Derivative XC8 Suppresses Sephadex-Induced Lung Inflammation in Rats and Ovalbumin-induced Acute and Chronic Asthma in Guinea Pigs.

BACKGROUND: Corticosteroids are the preferred option to treat asthma, however, they possess serious side effects and are inefficient in 10% of patients. Thus, new therapeutic approaches for asthma treatment are required. OBJECTIVE: To study the efficacy of a novel glutarimide derivative XC8 in a Sephadex-induced lung inflammation in rats as well as in acute and chronic ovalbumin-induced allergic asthma in guinea pigs. METHOD: Rats were treated with 0.18-18 mg/kg of XC8 intragastrically 4 times (24 h and 1 h prior to and 24 h and 45 h after endotracheal administration of Sephadex). The number of inflammatory cells in bronchoalveaolar lavages (BAL) was determined. Guinea pigs were treated with 0.045 -1.4 mg/kg (acute asthma) or with 1.4 and 7.0 mg/kg of XC8 (chronic asthma) intragastrically following the sensitization with ovalbumin and during aerosol challenge. Lung inflammation, numbers of eosinophils (BAL and lung tissue), goblet cells, degranulating mast cells and specific airway resistance (sRAW) were determined. The comparator steroid drug budesonide (0.5 mg/kg for rats and 0.16 mg/kg for guinea pigs) was administered by inhalation. RESULTS: XC8 reduced influx of eosinophils into BAL in Sephadex-induced lung inflammation model in rats (by 2.6-6.4 times). Treatment of acute asthma in guinea pigs significantly reduced eosinophils in guinea pigs in BAL (from 55% to 30%-39% of the total cell count) and goblet cells in lung tissue. In a model of acute and chronic asthma, XC8 reduced significantly the number of eosinophils and degranulating mast cells in the lung tissue. Treatment with XC8 but not with budesonide decreased the specific airway resistance in acute and chronic asthma model up to the level of naive animals. CONCLUSION: XC8 induced a profound anti-inflammatory effect by reducing eosinophils in BAL and eosinophils and degranulating mast cell numbers in the airway tissue. The anti-asthmatic effect of XC8 is comparable to that of budesonide. Moreover, in contrast to budesonide, XC8 was capable to reduce goblet cells and airway resistance.

Preclinical Development of ONC1-13B, Novel Antiandrogen for Prostate Cancer Treatment.

Recently new drugs targeting androgen-dependent axis have been approved for the treatment of castration-resistant prostate cancer (CRPC) - Zytiga and Xtandi (formerly MDV3100), several other candidates (for example, ARN-509) are in early phases of clinical trials. However despite significant improvement in overall survival with new treatments it is evident that resistance to these drugs develops. One of the approaches to overcome it is combination therapy and from this point of view some potential for drug-drug interactions can limit the application of the drug. We describe here the preclinical development of ONC1-13B, antagonist of androgen receptor, with similar to MDV3100 and ARN-509 mechanism of action. It efficiently inhibits DHT-stimulated PSA expression and proliferation of prostate cancer cells, prevents binding of androgens to the AR ligand-binding domain, androgen-stimulated AR nuclear translocation and coactivator complex formation. In the LnCaP-Z2 xenograft model of prostate cancer ONC1-13B inhibits tumor growth and suppresses PSA expression. The in vivo activity of ONC1-13B is comparable to that of MDV3100 at similar doses, and even higher, calculated per unit of concentration in plasma. Distribution of ONC1-13B to the brain is less than that shown for MDV3100 and ARN-509, decreasing the risk of GABA-related seizure development. Additionally ONC1-13B induces significantly lower in vitro CYP3A activity than for example MDV3100 (known strong CYP3A inducer) or ARN-509 and could be well suited for co-therapy with drugs that are known CYP3A substrates. Thus ONC1-13B is a new promising antiandrogen demonstrating high efficacy in a preclinical model of prostate cancer, with lower potential for seizures and drug-drug interaction.