A dose regimen-finding study to evaluate the safety, tolerability, pharmacokinetics, and activity of oratecan in subjects with advanced malignancies.

PURPOSE: Irinotecan is a commonly used chemotherapeutic in solid tumor malignancies. Oratecan is an investigational product comprised of encequidar methanesulfonate, a novel minimally absorbed P-glycoprotein pump inhibitor, and irinotecan. This study sought to determine the maximum tolerated dose (MTD) of oratecan in patients with advanced malignancies. METHODS: Using a "3 + 3″ dose-escalation design, patients were treated with oratecan on day 1 every 21 days. The irinotecan dose was escalated from 20 to 320 mg/m2. The encequidar methanesulfonate dose was fixed at 15 mg (12.9 mg free base). PK sampling for irinotecan, encequidar and its major metabolites was performed following a single dose of oratecan during cycle 1. Patients were treated until disease progression or unacceptable toxicity. RESULTS: Thirty-five patients were treated. The MTD was determined to be 280 mg/m2 every 21 days. Irinotecan and SN-38 plasma concentration-time profile showed that irinotecan exposure increased with dose and followed biexponential decay. Nine of 17 patients at oratecan dose levels 200 mg/m2 and above had SN-38 exposures comparable to those with intravenous irinotecan at standard dosing. None of the 35 patients achieved a radiologic response, ten patients had SD for > 8 weeks; the median progression-free survival for all treated patients was 9 weeks (95% CI 8.6-13.9). CONCLUSIONS: The MTD of oratecan was encequidar methanesulfonate 15 mg plus irinotecan 280 mg/m2. Exposure for irinotecan and SN-38 increased with increased dose. Potential antitumor activity was observed at the 280 and 320 mg/m2 dose levels. The safety profile of oratecan was comparable to that of intravenous irinotecan.

A phase Ib study of Oraxol (oral paclitaxel and encequidar) in patients with advanced malignancies.

PURPOSE: Oraxol is an oral formulation of paclitaxel administered with a novel, minimally absorbed P-glycoprotein inhibitor encequidar (HM30181A). This phase Ib study was conducted to determine the maximum-tolerated dose (MTD) of Oraxol administered at a fixed dose for up to 5 consecutive days in patients with advanced malignancies. METHODS: Part 1 of this study utilized a 3 + 3 dose-escalation design to determine the MTD of oral paclitaxel 270 mg plus oral encequidar 15 mg administered daily. Dose escalation was achieved by increasing the number of consecutive dosing days per week (from 2 to 5 days per week). Dosing occurred for 3 consecutive weeks out of a 4-week cycle. Part 2 treated additional patients at the MTD to determine tolerability and recommended phase II dose (RP2D). Adverse events, tumor responses, and pharmacokinetic profiles were assessed. RESULTS: A total of 34 patients (n = 24 in Part 1, n = 10 in Part 2) received treatment. The MTD of Oraxol was determined to be 270 mg daily × 5 days per week per protocol definition and this was declared the RP2D. The most common treatment-related adverse events were fatigue, neutropenia, and nausea/vomiting. Hypersensitivity-type reactions were not observed. Of the 28 patients evaluable for response, 2 (7.1%) achieved partial response and 18 (64.3%) achieved stable disease. Pharmacokinetic analysis showed rapid absorption of paclitaxel when administered orally following encequidar. Paclitaxel daily exposure was comparable following 2-5 days dose levels. CONCLUSION: The oral administration of encequidar with paclitaxel was safe, achieved clinically relevant paclitaxel levels, and showed evidence of anti-tumor activity.

Population pharmacokinetics for oral paclitaxel in patients with advanced/metastatic solid tumors.

Oraxol consists of an oral dosage form of the chemotherapeutic agent paclitaxel administered with a novel P-glycoprotein inhibitor encequidar methanesulfonate monohydrate (formerly named HM30181A), which allows oral treatment of cancers that would otherwise be treated with intravenous paclitaxel. Here we describe the population pharmacokinetics (popPK) analyses for oral paclitaxel in patients with advanced/metastatic solid tumors to characterize pharmacokinetic (PK) profiles and quantify sources of PK variability. The best fit popPK model for oral paclitaxel, based on data from seven clinical studies (197 patients with advanced/metastatic solid tumors), involves a linear two-compartment structural model containing first-order absorption with a short lag time and first-order elimination as well as a log additive error. In this popPK model, lower population estimates of central volume for Asian patients versus Caucasian patients did not translate into clinical meaningful differences in oral paclitaxel exposure. Age, sex, body weight or surface area, mild hepatic impairment, and mild to moderate renal impairment had no clinically meaningful effects on the systemic exposure of oral paclitaxel. Simulations were performed on clinical therapeutic dose (oral paclitaxel 205 mg/m2 once daily ×3 days per week) to predict exposure of oral paclitaxel and to support treatment benefits observed in a pivotal phase III trial.

Carbohydrate Ligands for COVID-19 Spike Proteins.

An outbreak of SARS-CoV-2 coronavirus (COVID-19) first detected in Wuhan, China, has created a public health emergency all over the world. The pandemic has caused more than 340 million confirmed cases and 5.57 million deaths as of 23 January 2022. Although carbohydrates have been found to play a role in coronavirus binding and infection, the role of cell surface glycans in SARS-CoV-2 infection and pathogenesis is still not understood. Herein, we report that the SARS-CoV-2 spike protein S1 subunit binds specifically to blood group A and B antigens, and that the spike protein S2 subunit has a binding preference for Lea antigens. Further examination of the binding preference for different types of red blood cells (RBCs) indicated that the spike protein S1 subunit preferentially binds with blood group A RBCs, whereas the spike protein S2 subunit prefers to interact with blood group Lea RBCs. Angiotensin converting enzyme 2 (ACE2), a known target of SARS-CoV-2 spike proteins, was identified to be a blood group A antigen-containing glycoprotein. Additionally, 6-sulfo N-acetyllactosamine was found to inhibit the binding of the spike protein S1 subunit with blood group A RBCs and reduce the interaction between the spike protein S1 subunit and ACE2.

Phase 1 Maximal Use Pharmacokinetic Study of Tirbanibulin Ointment 1% in Subjects With Actinic Keratosis.

Tirbanibulin is a novel tubulin polymerization and Src kinase signaling inhibitor. This study was designed to fully characterize tirbanibulin pharmacokinetics (PK) when applied topically under maximal use conditions. This was an open-label, parallel-group PK safety study of tirbanibulin ointment 1% applied to 25 cm2 of the face or balding scalp in adults with actinic keratosis (AK). Eligible subjects self-applied tirbanibulin once-daily for 5 days. PK sampling occurred on days 1, 3 and 4 at 0 hour (before dosing), and on day 5 at prespecified time points up to 24 hours after application. Safety assessments included adverse events and local skin reactions were evaluated up to day 29. Eighteen subjects (face or scalp, n = 9 each) completed the study. Subjects were White (100%), of mean [range] age 66.4 [43-83] years, predominantly men (83.3%) with Fitzpatrick skin type I to III (94.4%); baseline AK lesion count, mean [range] 8.2 [6-14]. All subjects had quantifiable but low plasma concentrations of tirbanibulin. On day 5, overall mean (standard deviation) maximum concentration (Cmax ) was 0.26 (0.23) ng/mL (or 0.60 nM), median time to maximum concentration was 6.91 hours, and mean (standard deviation) area under the plasma concentration-time curve from time 0 to 24 hours was 4.09 (3.15) ng ∙ h/mL. Four subjects experienced a total of 5 treatment-emergent adverse events that resolved. Mild to moderate erythema, flaking, or scaling in the treatment area peaked around day 8 before resolving or returning to baseline by day 29. In conclusion, under maximal use conditions, tirbanibulin ointment 1% for 5 days in the treatment of AK on the face or scalp was well tolerated and resulted in low systemic exposure with subnanomolar plasma concentrations.

Oral paclitaxel with encequidar compared to intravenous paclitaxel in patients with advanced cancer: A randomised crossover pharmacokinetic study.

AIMS: Paclitaxel is a widely used anti-neoplastic agent but has low oral bioavailability due to gut extrusion by P-glycoprotein (P-gp). Oral paclitaxel could be more convenient, less resource intensive, and more tolerable than intravenous administration. Encequidar (HM30181A) is a novel, minimally absorbed gut-specific P-gp inhibitor. We tested whether administration of oral paclitaxel with encequidar (oPac+E) achieved comparable AUC to intravenous paclitaxel (IVP) 80 mg/m2 . METHODS: We conducted a multi-centre randomised crossover study with two treatment periods. Patients (pts) with advanced cancer received either oral paclitaxel 615 mg/m2 divided over 3 days and encequidar 15 mg orally 1 hour prior, followed by IVP 80 mg/m2 , or the reverse sequence. PK blood samples were taken up to Day 9 for oPac+E and Day 5 for IVP. RESULTS: Forty-two patients were enrolled; 35 completed both treatment periods. AUC0-∞ was 5033.5 ± 1401.1 ng.h/mL for oPac+E and 5595.9 ± 1264.1 ng.h/mL with IVP. The geometric mean ratio (GMR) for AUC was 89.50% (90% CI 83.89-95.50). Mean absolute bioavailability of oPac+E was 12% (CV% = 23%). PK parameters did not change meaningfully after 4 weeks administration of oPac+E in an extension study. G3 treatment-emergent adverse events occurred in seven (18%) pts with oPac+E and two (5%) with IVP. Seventy-five per cent of patients preferred oPac+E over IVP. CONCLUSIONS: GMR for AUC was within the predefined acceptable range of 80-125% for demonstrating equivalence. oPac+E is tolerable and there is no evidence of P-gp induction with repeat administration. With further study, oPac+E could be an alternative to IVP.

Piragliatin (RO4389620), a novel glucokinase activator, lowers plasma glucose both in the postabsorptive state and after a glucose challenge in patients with type 2 diabetes mellitus: a mechanistic study.

CONTEXT: Glucokinase plays a key role in glucose homeostasis. Glucokinase activators can lower glucose levels in both animal and human type 2 diabetes, but their mechanism of action has never been explored in humans. OBJECTIVE: The objective of the study was to investigate the effects of the glucokinase activator piragliatin (RO4389620) on ß-cell function and glucose fluxes in both fasting and fed (oral glucose tolerance test) states in patients with type 2 diabetes. DESIGN: This was a phase Ib randomized, double-blind, placebo-controlled crossover trial of two (25 and 100 mg) doses of piragliatin. SETTING: This study was conducted at a clinical research center. PATIENTS: Patients included 15 volunteer ambulatory patients with mild type 2 diabetes. INTERVENTIONS: Interventions included three 10-h (-300' to +300') studies, with an interval of at least 14 d. Administration of a single dose of placebo or piragliatin 25 mg or piragliatin 100 mg at -120'. Oral glucose tolerance test (at 0') with dual (iv and oral routes) tracer dilution technique was conducted. MAIN OUTCOME MEASURES: The primary measure was plasma glucose concentration. The secondary measure was model assessed ß-cell function and tracer-determined glucose fluxes. RESULTS: Piragliatin caused a dose-dependent reduction of glucose levels in both fasting and fed states (P < 0.01). In the fasting state, piragliatin caused a dose-dependent increase in ß-cell function, a fall in endogenous glucose output, and a rise in glucose use (all P < 0.01). In the fed state, the primary effects of piragliatin were on ß-cell function (P < 0.01). CONCLUSIONS: The glucokinase activator piragliatin has an acute glucose-lowering action in patients with mild type 2 diabetes, mainly mediated through a generalized enhancement of ß-cell function and through fasting restricted changes in glucose turnover.

A phase I clinical and pharmacokinetic study of Ro 31-7453 given as a 7- or 14-day oral twice daily schedule every 4 weeks in patients with solid tumors.

PURPOSE: This is a dose-finding Phase I study of oral Ro 31-7453, a new class of antimitotic drug with promising preclinical activity in several chemoresistant models. EXPERIMENTAL DESIGN: Two schedules of oral Ro 31-7453 (every 12 h) given for either 7 or 14 consecutive days repeated every 4 weeks were explored consecutively. RESULTS: Thirty-seven patients with refractory cancer entered the study (14 on the 7-day schedule and 23 on the 14-day schedule). Median age was 63 years (range, 40-77 years), and median Karnofsky performance status was 80 (range, 60-100); the most frequent diagnosis was colorectal carcinoma (16 patients). Dose levels of 100, 200, 240, and 280 mg/m(2) twice daily (bid) for 7 days and 70, 100, 125, and 150 mg/m(2) bid for 14 days were explored. A total of 110 cycles were administered, the median number of cycles received was 3 (range, 1-7); six patients completed 6 or more cycles. Myelosuppression and mucositis were dose-limiting with both schedules. Fatigue and gastrointestinal toxicities other than mucositis were frequent but generally mild. The maximum tolerated doses were 200 mg/m(2) bid and 125 mg/m(2) bid for the 7- and 14-day schedules, respectively. Pharmacokinetic analysis showed rapid absorption and metabolism. The area under the concentration-time curve and trough concentrations of Ro 31-7453 and two active metabolites appeared dose proportional with a t(1/2) of approximately 9 h and a t(max) of approximately 4 h. One patient with pretreated lung cancer had a partial response. CONCLUSIONS: Both Ro 31-7453 regimens were feasible, but the 14-day schedule at the recommended dose of 125 mg/m(2) bid was selected for further monotherapy Phase II evaluation because of its higher preclinical activity. This regimen is convenient, well tolerated, and has a favorable pharmacokinetic profile.