Safety and pharmacokinetics of a kinin B1 receptor peptide agonist produced with different counter-ions

Abstract Several studies have shown the potential therapeutic utility of kinin B1 receptor (B1R) peptide agonists in neurological and ischemic cardiovascular diseases and brain cancer. Preclinical safety studies are a prerequisite for further drug development. The objectives of this study were to determine the acute toxicity and pharmacokinetics of the peptide B1R agonist, SarLys[dPhe8]desArg9-bradykinin (NG29), as trifluoroacetate (TFacetate) or acetate salt form, following intravenous injection in rats. A maximum tolerated dose (MTD) of NG29-TFacetate was established at 75 mg/kg from the results of a dose range-finding study (up to 200 mg/kg). The short-term (4-day) repeat-dose toxicity study of NG29, using its MTD value, showed that NG29-acetate exhibited minimal non-adverse clinical pathology changes in hematology, coagulation, clinical chemistry and urine parameters and severe kidney histopathological changes characterized by renal tubular degeneration. No such effects were observed with NG29-TFacetate. At the injection site, NG29-TFacetate was considered to be more locally irritating when compared to the acetate form. The extent of exposure and half-life values of NG29-TFacetate were comparable to the acetate form (AUC0–α of 10.2 mg/l*h vs. 9.9 mg/l*h; T1/2 of 2.3 h vs. 2.4 h). This study shows that in rats NG29-TFacetate exhibits a superior tolerability profile compared with the peptide acetate form.

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Tg.rasH2 Mice and not CByB6F1 Mice Should Be Used for 28-Day Dose Range Finding Studies Prior to 26-Week Tg.rasH2 Carcinogenicity Studies

International Journal of Toxicology ◽

10.1177/1091581817707458 ◽

2017 ◽

Vol 36 (4) ◽

pp. 287-292 ◽

Cited By ~ 1

Author(s):

Madhav G. Paranjpe ◽

Jessica Belich ◽

Tom J. Vidmar ◽

Reem H. Elbekai ◽

Marie McKeon ◽

...

Keyword(s):

Selection Process ◽

Dose Range ◽

Maximum Tolerated Dose ◽

High Dose ◽

Dose Selection ◽

Range Finding ◽

Body Weights ◽

Vehicle Test ◽

High Doses ◽

Dose Levels

Our recent retrospective analysis of data, collected from 29 Tg.rasH2 mouse carcinogenicity studies, determined how successful the strategy of choosing the high dose for the 26-week studies was based on the estimated maximum tolerated dose (EMTD) derived from earlier 28-day dose range finding (DRF) studies conducted in CByB6F1 mice. Our analysis demonstrated that the high doses applied at EMTD in the 26-week Tg.rasH2 studies failed to detect carcinogenic effects. To investigate why the dose selection process failed in the 26-week carcinogenicity studies, the initial body weights, terminal body weights, body weight gains, food consumption, and mortality from the first 4 weeks of 26-week studies with Tg.rasH2 mice were compared with 28-day DRF studies conducted with CByB6F1 mice. Both the 26-week and the earlier respective 28-day studies were conducted with the exact same vehicle, test article, and similar dose levels. The analysis of our results further emphasizes that the EMTD and subsequent lower doses, determined on the basis of the 28-day studies in CByB6F1 mice, may not be an accurate strategy for selecting appropriate dose levels for the 26-week carcinogenicity studies in Tg.rasH2 mice. Based on the analysis presented in this article, we propose that the Tg.rasH2 mice and not the CByB6F1 mice should be used in future DRF studies. The Tg.rasH2 mice demonstrate more toxicity than the CByB6F1 mice, possibly because of their smaller size compared to CByB6F1 mice. Also, the Tg.rasH2 males appear to be more sensitive than the female Tg.rasH2 mice.

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Development of a novel, pan-variant aerosol intervention for COVID-19

10.1101/2021.09.14.459961 ◽

2021 ◽

Author(s):

Robert H. Shoemaker ◽

Reynold A Panettieri ◽

Steven K Libutti ◽

Howard S Hochster ◽

Norman R Watts ◽

...

Keyword(s):

Clinical Trial ◽

Dose Range ◽

Binding Activity ◽

Lung Damage ◽

Repeat Dose ◽

Virus Binding ◽

Range Finding ◽

Viral Binding ◽

Effective Interventions ◽

Spread Of Infection

To develop a universal strategy to block SARS-CoV-2 cellular entry and infection represents a central aim for effective COVID-19 therapy. The growing impact of emerging variants of concern increases the urgency for development of effective interventions. Since ACE2 is the critical SARS-CoV-2 receptor and all tested variants bind to ACE2, some even at much increased affinity (see accompanying paper), we hypothesized that aerosol administration of clinical grade soluble human recombinant ACE2 (APN01) will neutralize SARS-CoV-2 in the airways, limit spread of infection in the lung and mitigate lung damage caused by deregulated signaling in the renin-angiotensin (RAS) and Kinin pathways. Here we show that intranasal administration of APN01 in a mouse model of SARS-CoV-2 infection dramatically reduced weight loss and prevented animal death. As a prerequisite to a clinical trial, we evaluated both virus binding activity and enzymatic activity for cleavage of Ang II following aerosolization. We report successful aerosolization for APN01, retaining viral binding as well as catalytic RAS activity. Dose range-finding and IND-enabling repeat-dose aerosol toxicology testing were conducted in dogs. Twice daily aerosol administration for two weeks at the maximum feasible concentration revealed no notable toxicities. Based on these results, a Phase I clinical trial in healthy volunteers can now be initiated, with subsequent Phase II testing in individuals with SARS-CoV-2 infection. This strategy could be used to develop a viable and rapidly actionable therapy to prevent and treat COVID-19, against all current and future SARS-CoV-2 variants.

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A Novel RAD51 Inhibitor, CYT01B, Shows Anti-Cancer Activity in Preclinical Models of Aid Expressing Lymphomas

Blood ◽

10.1182/blood-2018-99-119351 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 2944-2944

Author(s):

Muneer G Hasham ◽

Darryl Patrick ◽

Leanne Bedard ◽

Joseph Vacca ◽

Casey McComas ◽

...

Keyword(s):

Cell Line ◽

Cytidine Deaminase ◽

Clinical Chemistry ◽

Lymphoblastic Leukemia ◽

Dose Range ◽

Leukemia Cell Line ◽

Range Finding ◽

Anti Cancer ◽

Cancer Activity

Abstract Activation Induced Cytidine Deaminase (AID) is a DNA directed cytidine deaminase that is normally only expressed in activated B-cells to promote somatic hypermutations and immunoglobulin class switching. Unlike site-specific recombinases (e.g. RAG1/2), AID lacks target site specificity and can generate DNA damage at widespread locations throughout the genome. In cancer cells, AID expression promotes high levels of DNA replication stress, and results in dependency upon the homologous recombination factor RAD51. We have shown previously that a novel RAD51 inhibitor, CYT01B, functions by disrupting RAD51 focus formation which reduces the nuclear concentration of RAD51 and promotes RAD51 protein degradation. Here we present the in vitro and in vivo pharmacological characterization of CYT01B. We first analyzed the permeability and stability of the compound using Caco-2 and liver microsome assays. CYT01B shows low efflux and is stable with low intrinsic clearance rates (< 30 ml/min/mg protein) in mouse, rat, dog, and human, but not in cynomolgus monkey liver microsomes. In vivo, CYT01B showed oral bioavailability that correlated well with Caco-2 permeability (36.9% in monkeys up to 86.5% in rats). Additionally, CYT01B exhibited a minimum half-life of 4 hours in all species tested (mouse, rat, dog, and monkey). We then examined off target liabilities by performing kinome inhibition and Panlabs safety panel screens. CYT01B showed negligible (<50%) inhibition across 371 kinases tested, while only two targets showed greater than 50% inhibition in the Panlabs panel. CYT01B displayed activity in several human-to-mouse cell line xenograft models. In a systemic model of chronic lymphoblastic leukemia (CLL), the tumor burden in the bone marrow of CYT01B-treated mice was reduced by approximately 30%. In two different subcutaneous engraftment models of either a Burkitt's lymphoma cell line (Daudi) or an acute lymphoblastic leukemia cell line (CCRF-SB), mice treated with CYT01B showed tumor growth inhibition of 49% and 88%, respectively. Lastly, CYT01B was well tolerated in rat 7-day dose range finding studies. Rats were treated with 20, 80, and 240 mg/kg once per day by oral gavage. There were no observed changes in hematology or clinical chemistry, and no observed histopathological toxicities. Taken together, these data demonstrate that CYT01B is a cell permeable, metabolically stable, and orally bioavailable small molecule, with anti-cancer activity in multiple preclinical lymphoid cancer models. Overall, this provides the basis for continued preclinical development of an AID/RAD51 synthetic lethal therapeutic paradigm that may be applicable to various hematologic malignancies. Disclosures Patrick: Cyteir Therapeutics: Consultancy. Bedard:Cyteir Therapeutics: Consultancy. Vacca:Cyteir Therapeutics: Consultancy. McComas:Cyteir Therapeutics: Consultancy. Castro:Cyteir Therapeutics: Consultancy. Day:Cyteir Therapeutics: Employment. Mills:Cyteir Therapeutics: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees.

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Tolerability profile of zolmitriptan (Zomig™ 311C90), a novel dual central and peripherally acting 5HT1B/1D agonist

Cephalalgia ◽

10.1177/0333102497017s1806 ◽

1997 ◽

Vol 17 (18_suppl) ◽

pp. 41-52 ◽

Cited By ~ 40

Author(s):

Jg Edmeads ◽

Ds Millson

Keyword(s):

Clinical Pharmacology ◽

Adverse Event ◽

Adverse Events ◽

Clinical Studies ◽

Clinical Chemistry ◽

Dose Range ◽

Tolerability Profile ◽

Term Study ◽

Long Term Study

Zolmitriptan (Zomig™, formerly 311C90) at doses of 0.5–50 mg was administered to 316 unique volunteers in clinical pharmacology studies and 2,750 unique patients in eight clinical studies of acute migraine treatment. Overall, subjects received almost 50,000 doses; 97% of exposures were at doses >2.5 mg. In the clinical pharmacology studies, the overall incidence of subject exposures experiencing at least one adverse event was 52% with zolmitriptan 2.5 mg (28% with placebo). In placebo-controlled studies, the overall incidence of patients with at least one adverse event was dose-dependent for zolmitriptan over the 1–15 mg dose range, e.g. 42% and 46% with 1 and 2.5 mg, respectively and 58% with 5 mg (29% with placebo). Only four serious adverse events attributable to zolmitriptan were reported. In a long-term study, during which 2,058 outpatients treated a total of 31,579 migraine attacks with either one or two zolmitriptan 5 mg doses over a period of up to 1 year, the number of attacks associated with at least one adverse event was similar after one (26%) and two (24%) doses. The majority (59%) of the adverse events reported in this study (59%) occurred within 2 h of dosing, were predominantly mild (59%) or moderate (35%) in intensity, of ≦4 h duration (58%), required no further action (94%). In placebo-controlled studies, the percentage of patients who reported severe adverse events was similar with zolmitriptan 2.5 mg (4%) and placebo (5%). The most frequently reported adverse events with zolmitriptan in the placebo-controlled clinical studies were asthenia, heaviness (other than chest or neck), dry mouth, nausea, dizziness, somnolence, paresthesia and warm sensations. The type and severity of the adverse events was not influenced by gender (although the frequency of reported adverse events was higher in females, as was the case in the placebo group), age, presence of aura prior to the attack, association of migraine with menstruation, concurrent medication, or by the addition of a second zolmitriptan dose. Zolmitriptan showed a similar tolerability profile in the long-term study, in which a low withdrawal rate due to adverse events of 8% was observed. Zolmitriptan was not associated with an increased frequency of central nervous system-related adverse events in a comparative study of sumatriptan, despite pre-clinical and neurophysiological evidence of a dual peripheral and central action of zolmitriptan. Moreover, zolmitriptan doses of 5–20 mg produced no statistically significant effects on objective assessments of psychometric function. Zolmitriptan had no clinically significant effects on blood pressure (even in patients with controlled mild to moderate hypertension or impaired renal function), ECGs (e.g. there was no evidence of ischemic events) or clinical chemistry, hematological or urinalysis measurements. In summary, zolmitriptan is well tolerated, particularly at the recommended dose of 2.5 mg. Zolmitriptan has a well-defined dose-response with 2.5 mg proving highly effective and optimizing the benefit/risk ratio of treatment. Thus, zolmitriptan is well suited as an acute oral treatment for migraine in the outpatient setting.

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Phase II trial of iboctadekin (rhIL-18) on a daily X 5 schedule in metastatic melanoma (MM)

Journal of Clinical Oncology ◽

10.1200/jco.2006.24.18_suppl.10043 ◽

2006 ◽

Vol 24 (18_suppl) ◽

pp. 10043-10043 ◽

Cited By ~ 2

Author(s):

J. M. Kirkwood ◽

R. Kefford ◽

T. Logan ◽

P. N. Mainwaring ◽

M. Millward ◽

...

Keyword(s):

Dose Level ◽

Phase Ii ◽

Phase Ii Trial ◽

Dose Range ◽

Maximum Tolerated Dose ◽

Tolerability Profile ◽

Open Label ◽

Two Phase ◽

Stage 1 ◽

Dose Levels

10043 Background: Interleukin-18 (IL-18) is an immunostimulatory cytokine with potent antitumor activity in preclinical models. Two phase I studies of recombinant human (rh) IL-18 explored a wide dose range (0.03–1.0 mg/kg) without reaching a maximum tolerated dose (MTD) on the daily × 5 schedule. Pharmacodynamic data including inflammatory cytokine production and activation of lymphocyte subsets revealed optimal biologic activity at the lower end of the dose range (0.01–0.2 mg/kg) as did 2 unconfirmed partial responses (PRs) in a MM and a renal cancer patient (pt) at 0.1 mg/kg. Methods: An open-label, randomized, phase II trial in 60 adult pts with previously untreated MM was conducted to evaluate the efficacy and safety of rhIL-18 administered as a 2-hour IV infusion daily × 5 every 28 days for 6 cycles. Pts with PS ≤ 1, without known CNS involvement, and with adequate end organ function were randomized in stage 1 to 3 dose levels of IL-18 stratified according to AJCC M stage 1a/b vs. 1c. Two confirmed responses for a given dose level in Stage 1 were required to enroll 20 additional pts/level in Stage 2. The 1° objective was determination of overall response rate (ORR) for each dose level. Progression-free survival (PFS), tolerability, and immunogenicity were 2° endpoints. Results: 64 pts were treated at 3 dose levels. Nine pts remain on study. One pt experienced a confirmed PR. Based on preliminary data, the difference in PFS 6 months (mos) was significant (p=0.03) for 0.01 vs 0.1 mg/kg. Most common toxicities were mild to moderate fever, rigors, chills, n/v, and headache. Anti-IL18 antibody (Ab) development correlated with dose level. No clinically significant adverse events were associated with Ab development. Conclusion: Iboctadekin has an acceptable tolerability profile and has activity in MM but insufficient confirmed responses have been observed at this time to initiate Stage 2. Preliminary PFS 6 months indicates an advantage for pts treated at the lowest dose. [Table: see text] [Table: see text]

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A three-part, phase I, dose-escalation study of GSK1120212, a potent MEK inhibitor, administered orally to subjects with solid tumors or lymphoma

Journal of Clinical Oncology ◽

10.1200/jco.2009.27.15_suppl.e14584 ◽

2009 ◽

Vol 27 (15_suppl) ◽

pp. e14584-e14584 ◽

Cited By ~ 5

Author(s):

D. S. Thompson ◽

K. Flaherty ◽

W. Messersmith ◽

K. Harlacker ◽

S. Nallapareddy ◽

...

Keyword(s):

Cell Proliferation ◽

Solid Tumors ◽

Dose Escalation ◽

Tumor Regression ◽

Dose Range ◽

Mek Inhibitor ◽

Maximum Tolerated Dose ◽

Repeat Dose ◽

Post Dose ◽

Dose Escalation Study

e14584 Background: GSK1120212 is a potent and highly selective inhibitor of MEK1, a component of the MAP kinase pathway. GSK1120212 demonstrates efficient inhibition of p-ERK which correlates with inhibition of cell proliferation and induction of apoptosis. PO administration of GSK1120212 achieved tumor regression in multiple mouse xenograft models. The objectives of this study are to define the maximum tolerated dose (MTD) and to evaluate the pharmacokinetics (PK) and pharmacodynamic (PD) effects of GSK1120212. Methods: In Part 1, patients (pts) with solid tumors or lymphoma are enrolled in successive cohorts and receive a single PO dose of GSK1120212 followed by QD doses on days 1 - 21 of each 28-day cycle. Tumor response is assessed Q 8 weeks. PK blood samples are collected from all pts. Ophthalmic exams are administered at baseline and as clinically warranted. Dose escalation occurs via an accelerated titration followed by a standard 3+3 escalation. In Part 2, pts with pancreatic or K-Ras mutant CRC will be enrolled at the MTD. In Part 3, pts with biopsiable tumors will enroll at MTD and sub-MTD doses. Tumor biopsies will be taken pre- and post-dose to measure pERK and other markers of cell proliferation. Results: Six pts with advanced malignancies (neuroendocrine, thyroid, colorectal (n=2), melanoma (n=2) have been treated with tablets at four dose levels: 0.125 (n=2), 0.25 (n=1), 0.5 (n=2), and 1.0 mg (n=1). No DLTs or grade 2 toxicities have been reported. One patient was on study for over 17 weeks. Based on mean AUC and Cmax, GSK1120212 exposures following 15 days of repeat-dose administration were approximately dose proportional across the dose range (0.125–0.5 mg) with a median Tmax of approximately 1.5 hours. Conclusions: GSK1120212 has been well tolerated to date. Dose escalation is ongoing. [Table: see text]

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Activation of Kinin B1R Upregulates ADAM17 and Results in ACE2 Shedding in Neurons

International Journal of Molecular Sciences ◽

10.3390/ijms22010145 ◽

2020 ◽

Vol 22 (1) ◽

pp. 145

Author(s):

Rohan Umesh Parekh ◽

Srinivas Sriramula

Keyword(s):

Protein Expression ◽

Renin Angiotensin System ◽

Neuronal Cultures ◽

Wild Type ◽

High Concentration ◽

Neurogenic Hypertension ◽

B1 Receptor ◽

Gene And Protein Expression ◽

Kinin B1 Receptor ◽

Specific Antagonist

Angiotensin converting enzyme 2 (ACE2) is a critical component of the compensatory axis of the renin angiotensin system. Alterations in ACE2 gene and protein expression, and activity mediated by A Disintegrin And Metalloprotease 17 (ADAM17), a member of the “A Disintegrin And Metalloprotease” (ADAM) family are implicated in several cardiovascular and neurodegenerative diseases. We previously reported that activation of kinin B1 receptor (B1R) in the brain increases neuroinflammation, oxidative stress and sympathoexcitation, leading to the development of neurogenic hypertension. We also showed evidence for ADAM17-mediated ACE2 shedding in neurons. However, whether kinin B1 receptor (B1R) activation has any role in altering ADAM17 activity and its effect on ACE2 shedding in neurons is not known. In this study, we tested the hypothesis that activation of B1R upregulates ADAM17 and results in ACE2 shedding in neurons. To test this hypothesis, we stimulated wild-type and B1R gene-deleted mouse neonatal primary hypothalamic neuronal cultures with a B1R-specific agonist and measured the activities of ADAM17 and ACE2 in neurons. B1R stimulation significantly increased ADAM17 activity and decreased ACE2 activity in wild-type neurons, while pretreatment with a B1R-specific antagonist, R715, reversed these changes. Stimulation with specific B1R agonist Lys-Des-Arg9-Bradykinin (LDABK) did not show any effect on ADAM17 or ACE2 activities in neurons with B1R gene deletion. These data suggest that B1R activation results in ADAM17-mediated ACE2 shedding in primary hypothalamic neurons. In addition, stimulation with high concentration of glutamate significantly increased B1R gene and protein expression, along with increased ADAM17 and decreased ACE2 activities in wild-type neurons. Pretreatment with B1R-specific antagonist R715 reversed these glutamate-induced effects suggesting that indeed B1R is involved in glutamate-mediated upregulation of ADAM17 activity and ACE2 shedding.

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Dried Blood Spot Analysis of Donepezil in Support of a GLP 3-month Dose-Range Finding Study in Rats

International Journal of Toxicology ◽

10.1177/1091581812447957 ◽

2012 ◽

Vol 31 (4) ◽

pp. 337-347 ◽

Cited By ~ 5

Author(s):

Susan R. Meier-Davis ◽

Min Meng ◽

Weiwei Yuan ◽

Lisa Diehl ◽

Fatima M. Arjmand ◽

...

Keyword(s):

Dose Range ◽

Systemic Exposure ◽

Pharmacokinetic Profile ◽

Dried Blood Spot ◽

Topical Formulation ◽

Carcinogenicity Study ◽

Range Finding ◽

Donepezil Hydrochloride ◽

Blood Spot

Donepezil hydrochloride is a reversible acetyl cholinesterase inhibitor approved for Alzheimer disease treatment. As an alternate therapy, a donepezil hydrochloride transdermal patch is in development. Recommended nonclinical safety studies include a 3-month Good Laboratory Practice (GLP) dose-range finding (DRF) study prior to conducting the 2-year dermal carcinogenicity study in rats. Demonstration of systemic exposure is necessary to interpret the in vivo data. Previous nonclinical reports supporting oral dosing have utilized liquid chromatography tandem mass spectrometry (LC/MS/MS) to quantify donepezil concentrations in plasma. Smaller species with limited blood volumes do not allow serial sampling to derive the full pharmacokinetic profile from a single animal. Therefore, the option of another analytical method requiring decreased sample volumes is desirable as it would decrease the required number of animals while obtaining the complete profile. The dried blood spot (DBS) technique allows drug level measurement from a few microliters; however, the method is still not widely utilized in GLP studies. Because donepezil plasma levels are known by the oral route, DBS was used to bridge the previous oral data and to support a 13-week GLP DRF study for repeated topical application in rats, comparing oral administration with 4 topical formulations. The DBS method was validated and demonstrated robustness and reproducibility for application to the DRF study. The assay results were comparable to a previously reported plasma LC/MS/MS assay-derived pharmacokinetic profile and provided justification for selection of the topical formulation and dose levels for the subsequent dermal carcinogenicity study.

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