The Length of Disulfide Bond-Containing Linkages Impacts the Oral Absorption and Antitumor Activity of Paclitaxel Prodrugs-Loaded Nanoemulsions

Nanoscale ◽  
2021 ◽  
Author(s):  
Yanlin Gao ◽  
Shiyi Zuo ◽  
Lingxiao Li ◽  
Tian Liu ◽  
Fudan Dong ◽  
...  

Rational design of oral paclitaxel (PTX) preparations is still a challenge. Many studies focus on developing PTX-loaded nanoemulsions (NEs) for oral administration. Unfortunately, PTX has poor affinity with the commonly...

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 1084-1084 ◽  
Author(s):  
Ming-Shen Dai ◽  
Ta-Chong Chao ◽  
Chang-Fan Chiu ◽  
Yen-Shen Lu ◽  
Her-Shyongi Shiah ◽  
...  

1084 Background: Intravenous (IV) paclitaxel is an effective treatment for breast cancer. Oral administration paclitaxel is preferable to IV regarding minimizing IV injections, anaphylactic reactions to cremaphor, steroid pre-medications, hospital visits, and relevant costs. However, paclitaxel has poor oral absorption due to active excretion by P-glycoprotein (P-gp) in the intestinal cells. Oraxol (Athenex, USA) is an oral paclitaxel and HM30181, a novel oral inhibitor of intestinal P-gp which enables the oral administration of paclitaxel. We report the final results of a pharmacokinetics (PK) study, including clinical response and tolerability of Oraxol in treatment of metastatic breast cancer patients. Methods: Multicenter, single-arm, open-label, PK study of Oraxol (HM30181A at 15mg, plus oral paclitaxel 205mg/m2) administered orally for 3 consecutive days weekly for up to 16 weeks. Paclitaxel PK was assessed at week-1 and week-4. Tumor Response was measured at weeks 8 and 16 using RECIST criteria 1.1. Toxicity was assessed using CTCAE v4.03. Results: Twenty-eight MBC patient were studied with a mean age of 56.6 years (range: 38 - 79 yrs). 26 patients had failed mutiple previous chemotherapies. There were 11 (42.3%) partial response, 12 (46.2%) stable disease and 3 (11.5%) progressive disease in 26 evaluable patients. Three patients had treatment-related SAEs (grade ≥3 neutropenia) and all patients recovered completely. PK results showed that the AUC of oral paclitaxel at week-1 was reproducible at week-4 (3050 to 3594 ng-hr/mL). Conclusions: Oral paclitaxel showed very encouraging anti-cancer activity in MBC patients who failed previous chemotherapies with acceptable toxicity. Weekly oral paclitaxel can achieve paclitaxel exposure similar to that of weekly IV paclitaxel (80mg/m2) reported previously. PK of oral paclitaxel is reproducible. Clinical trial information: NCT03165955.


1982 ◽  
Vol 101 (4) ◽  
pp. 550-554 ◽  
Author(s):  
K. W. Wenzel ◽  
J. Döring

Abstract. Since antidopaminergic drugs are known to elevate basal and TRH-stimulated TSH-serum levels and since this effect was also shown after iv administration of the novel dopamine antagonistic agent domperidone, it was investigated, whether this antiemetic drug could interfere after oral intake with the evaluation of thyroid function. Oral domperidone caused a marked TSH-enhancement of TRH-induced TSH increments in 6 out of 14 euthyroid subjects, with no statistical significance, however. The difference between oral and parenteral influence as well as inter-individual changes are probably due to the varying first pass effect of the drug after oral absorption.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Larbi Krimbou ◽  
Ravi Jahagirdar ◽  
Dana Bailey ◽  
Anouar Hafiane ◽  
Isabelle Ruel ◽  
...  

The novel compound RVX-208 is a small molecule that upregulates the gene expression of apoA-I and raises HDL-C in non-human primates. Here, we examined the effects of oral administration of RVX-208 on serum apoA-I and HDL-C levels , HDL size distribution, and HDL function. African green monkeys received RVX-208 (7.5, 15 and 30 mg/kg; twice daily and 60 mg/kg; once daily) or vehicle control for 28, 42, and 63 days. We report that RVX-208 chronic treatment resulted in a highly significant increase in the average of serum apoA-I and HDL-C levels (57% and 92%, respectively). Interestingly, RVX-208 treatment modified the distribution of HDL particle size causing a significant increase in preβ1-LpA-I and larger α1-LpA-I species. The ability of serum to promote cholesterol efflux via ABCA1, ABCG1 or SR-BI-dependent pathways in a cell culture model was significantly increased by RVX-208. The phase Ia safety and pharmacokinetic human study comprised of a total of 80 subjects. In the multiple ascending dose arm, 24 participants were randomly assigned to 3 cohorts of 8 healthy volunteers (6 active and 2 placebo), and received oral administration of RVX-208 at 2, 3 and 8 mg/kg per day or placebo for 7 days. The compound was well tolerated and had good oral absorption meeting the objectives of safety and pharmacokinetics. ApoA-I, HDL-C, HDL size distribution and ABCA1-dependent cholesterol efflux were assessed at days 1 (predose) and 7. The percent change from baseline to day 7 for apoA-I was 11% higher (P = 0.03) in the RVX-208 treated participants compared to placebo. Interestingly, preβ1-LpA-I change was 30% (P = 0.02) higher in the actively treated group and was found to strongly correlate with increased apoA-I levels (R2 = 0.72). Furthermore, ABCA1-dependent cholesterol efflux change was 10% higher (P = 0.03) and was found to correlate with increased preβ1-LpA-I . Taken together, these pharmacodynamic data from human healthy volunteers show consistent trends in apoA-I production and HDL functionality, supporting the findings in the African green monkey. Further investigation of the effect of RVX-208 on the HDL metabolic pathway is ongoing in humans and animals to establish the mechanisms of action and therapeutic potential in treating atherosclerotic cardiovascular disease.


2011 ◽  
Vol 105 (06) ◽  
pp. 1060-1071 ◽  
Author(s):  
Jin Woo Park ◽  
Ok Cheol Jeon ◽  
Sang Kyoon Kim ◽  
Taslim Al-Hilal ◽  
Kyung-Min Lim ◽  
...  

SummaryThis study was designed to develop a solid oral dosage form of deoxycholic acid (DOCA)-conjugated low-molecular-weight heparin (LMWH) and to evaluate its oral absorption, distribution, and metabolic stability for the prospect of providing an orally bioavailable LMWH. The LMWH derivative (LHD) was synthesised and then formulated with solubilisers and other pharmaceutical excipients to form a solid tablet. Its absorption and distribution after oral administration were evaluated in mice, rats, and monkeys. The in vitro metabolic stability of LHD was examined by liver microsome assays. More than 80% of LHD was released from the tablet within 60 minutes, guaranteeing rapid tablet disintegration after oral administration. Oral bioavailability of LHD in mice, rats and monkeys were 16.1 ± 3.0, 15.6 ± 6.1, and 15.8 ± 2.5%, respectively. After the oral administration of 131I-tyramine-LHD, most of the absorbed drug remained in the blood circulation and was eliminated mainly through the kidneys. LHD was hardly metabolised by the liver microsomes and showed a stable metabolic pattern similar to that of LMWH. In a rat thrombosis model, 10 mg/kg of orally administered LHD reduced thrombus formation by 60.8%, which was comparable to the antithrombotic effect of the subcutaneously injected LMWH (100 IU/ kg). Solid tablets of LHD exhibited high oral absorption and statistically significant therapeutic effects in preventing venous thromboembolism. Accordingly, LHD tablets are expected to satisfy the unmet medical need for an oral heparin-based anticoagulant as an alternative to injectable heparin and oral warfarin.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Jong Bong Lee ◽  
Masar Radhi ◽  
Elena Cipolla ◽  
Raj D. Gandhi ◽  
Sarir Sarmad ◽  
...  

Abstract Although adenosine and its analogues have been assessed in the past as potential drug candidates due to the important role of adenosine in physiology, only little is known about their absorption following oral administration. In this work, we have studied the oral absorption and disposition pathways of cordycepin, an adenosine analogue. In vitro biopharmaceutical properties and in vivo oral absorption and disposition of cordycepin were assessed in rats. Despite the fact that numerous studies showed efficacy following oral dosing of cordycepin, we found that intact cordycepin was not absorbed following oral administration to rats. However, 3′-deoxyinosine, a metabolite of cordycepin previously considered to be inactive, was absorbed into the systemic blood circulation. Further investigation was performed to study the conversion of 3′-deoxyinosine to cordycepin 5′-triphosphate in vitro using macrophage-like RAW264.7 cells. It demonstrated that cordycepin 5′-triphosphate, the active metabolite of cordycepin, can be formed not only from cordycepin, but also from 3′-deoxyinosine. The novel nucleoside rescue metabolic pathway proposed in this study could be responsible for therapeutic effects of adenosine and other analogues of adenosine following oral administration. These findings may have importance in understanding the physiology and pathophysiology associated with adenosine, as well as drug discovery and development utilising adenosine analogues.


2020 ◽  
Vol 21 (7) ◽  
pp. 2512
Author(s):  
Lu-Lu Yin ◽  
Jia-Kun Xu ◽  
Xiao-Juan Wang ◽  
Shu-Qin Gao ◽  
Ying-Wu Lin

Protein design is able to create artificial proteins with advanced functions, and computer simulation plays a key role in guiding the rational design. In the absence of structural evidence for cytoglobin (Cgb) with an intramolecular disulfide bond, we recently designed a de novo disulfide bond in myoglobin (Mb) based on structural alignment (i.e., V21C/V66C Mb double mutant). To provide deep insight into the regulation role of the Cys21-Cys66 disulfide bond, we herein perform molecular dynamics (MD) simulation of the fluoride–protein complex by using a fluoride ion as a probe, which reveals detailed interactions of the fluoride ion in the heme distal pocket, involving both the distal His64 and water molecules. Moreover, we determined the kinetic parameters of fluoride binding to the double mutant. The results agree with the MD simulation and show that the formation of the Cys21-Cys66 disulfide bond facilitates both fluoride binding to and dissociating from the heme iron. Therefore, the combination of theoretical and experimental studies provides valuable information for understanding the structure and function of heme proteins, as regulated by a disulfide bond. This study is thus able to guide the rational design of artificial proteins with tunable functions in the future.


2014 ◽  
Vol 17 (1) ◽  
pp. 106 ◽  
Author(s):  
Yusuke Tanaka ◽  
Toshiyuki Baba ◽  
Koji Tagawa ◽  
Ryoichi Waki ◽  
Shunji Nagata

Purpose. This study aimed to develop a novel approach for predicting the oral absorption of low-solubility drugs by considering regional differences in solubility and permeability within the gastrointestinal (GI) tract. Methods. Simulated GI fluids were prepared to reflect rat in vivo bile acid and phospholipid concentrations in the upper and lower small intestine. The saturated solubility and permeability of griseofulvin (GF) and albendazole (AZ), a drug with low aqueous solubility, were measured using these simulated fluids, and fraction absorbed (Fa) at time t after oral administration was calculated. Results. The saturated solubility of GF and AZ, a drug with low aqueous solubility, differed considerably between the simulated GI fluids. Large regional differences in drugs concentration were also observed following oral administration in vivo. The predicted Fa values using solubility and permeability data of the simulated GI fluid were found to correspond closely to the in vivo data. Conclusion. These results indicated the importance of evaluating regional differences in drug solubility and permeability in order to predict oral absorption of low-solubility drugs accurately. The new methodology developed in the present study could be useful for new oral drug development. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.


2009 ◽  
Vol 1 ◽  
pp. OED.S2857 ◽  
Author(s):  
Ravi S. Talluri ◽  
Ripal Gaudana ◽  
Sudharshan Hariharan ◽  
Ashim K. Mitra

Objective To delineate the plasma pharmacokinetics and determine the corneal uptake of valine based stereoisomeric dipeptide prodrugs of acyclovir (ACV) in rats. Methods Male Sprague-Dawley rats were used for the study. Pharmacokinetics of ACV, L-valine-acyclovir (LACV), L-valine-D-valine-acyclovir (LDACV) and D-valine-L-valine acyclovir (DLACV) prodrugs were delineated. These compounds were administered intravenously as a bolus via jugular vein cannula and orally by gavage. Samples were purified by protein precipitation method and analyzed by LC-MS/MS. Pertinent pharmacokinetic parameters were obtained by using WinNonlin. Corneal uptake studies of LDACV and LACV were studied following oral administration. Results Following i.v. administration, the area under the curve (AUC) in μM*min of generated ACV was in the order of LACV > LDACV > DLACV indicating their rate of metabolism. The AUC values of total drug obtained in the systemic circulation after oral administration LACV and LDACV were 1077.93 ± 236.09 and 1141.76 ± 73.67 μM*min, respectively. DLACV exhibited poor oral absorption. Cmax (μM) and AUC of the intact prodrug obtained in the systemic circulation following oral administration of LDACV were almost 4–5 times higher than LACV. Moreover, concentrations achieved in the cornea after oral administration of LDACV were almost two times of LACV. Conclusions LDACV increased both the oral bioavailability and subsequent in vivo corneal uptake of ACV Hence, LDACV can be considered as the most promising drug candidate for delivery of ACV, in treatment of both genital herpes and ocular herpes keratitis after oral administration.


Antioxidants ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 913
Author(s):  
Hye-Rin Jin ◽  
Suyong Lee ◽  
Soo-Jin Choi

The grains of Tartary buckwheat (Fagopyrum esculentum) are traditionally consumed on a daily basis and are used in the preparation of diverse processed foods owing to the high concentration of rutin, an antioxidant compound. However, rutin is highly concentrated in hull and bran, but not in edible flour fractions. Rutin-enriched TB flour extracts (TBFEs) were obtained by hydrothermal treatment (autoclaving, boiling, or steaming) and their pharmacokinetic profiles were evaluated following a single-dose oral administration in rats. The antioxidant and protective activities of the extracts against alcoholic liver disease (ALD) were investigated after repetitive oral administration of TBFEs for 28 days prior to ethanol ingestion. The results demonstrated that rutin-enriched TBFEs had better oral absorption and was retained longer in the bloodstream than native TBFE or standard rutin. The activities of antioxidant enzymes and intracellular antioxidant levels increased in ALD rats following TBFE treatments, especially following the administration of rutin-enriched TBFEs. The antioxidant activity of TBFEs consequently contributed toward protecting the liver against injury caused by repetitive ethanol administration, as confirmed by analyzing relative liver weight, liver injury markers, lipid peroxidation, and calcium permeability. These results suggest the promising potential of TBFEs as antioxidant-enriched functional foods for human health.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4011-4011 ◽  
Author(s):  
Paul W. Manley ◽  
Jürgen Mestan ◽  
Jennifer Sheng ◽  
Phi Tran ◽  
Mark Kagan

Abstract Background There is a growing tendency for drugs to be grouped according to their perceived ‘class effects’, regardless of the different pharmacological profiles of the parent drugs and of their metabolites. Imatinib, dasatinib, nilotinib, bosutinib and, most recently ponatinib, are approved tyrosine kinase inhibitor (TKI) therapies for chronic myeloid leukemia (CML), which are clinically efficacious as a result of ABL1/ BCR-ABL inhibition. Following their oral administration at standard therapeutic doses, the parent drugs are the major circulating species by area under the curve (AUC). However in the case of imatinib, dasatinib, bosutinib and ponatinib, the exposure of patients to major metabolites can be substantial compared to that of parent drug, with CGP74588 (which is much less active than imatinib against both BCR-ABL and KIT; Bioorg Med Chem 2013;21:3231) representing 10% of imatinib by AUC (Clin Pharmacokinet 2005;44:879); M20 and M24 representing 45 and 25% of dasatinib (Drug Met Disp 2008;36:1341), M2 and M5 representing 19 and 25% of bosutinib (Clinical Pharmacology Biopharmaceutics Review, http://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm) and AP24600 representing 58% of ponatinib (Clinical Pharmacology Biopharmaceutics Review, http://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm). Such major metabolites might make significant contributions to the on- and off-target effects of the parent drugs in vivoand may be responsible for some of the side-effects observed in patients. Here we report on the metabolism of the potent and selective BCR-ABL inhibitor, nilotinib and the preclinical profile of its major metabolites. Methods The metabolism of nilotinib was characterised in healthy subjects after oral administration of two capsules containing 200 mg [14C]-labelled nilotinib (50 μCi), and blood plasma, feces and urine samples were assayed in an appropriate scintillant either by counting an aliquot directly or after homogenisation, air-drying and solubilisation. Metabolites were characterised and quantified by HPLC with radioactivity detection and identified by mass spectrometry (LC-MS/MS) and, when possible, co-elution with non-radiolabeled authentic samples. Synthesised samples of the metabolites were evaluated in a large panel of assays for potential effects on kinase and non-kinase enzymes, G-protein coupled receptors, cell transporters, ion channels and nuclear receptors. Results The oral absorption of nilotinib was determined to be ≥30% and excretion was mainly into the feces (93.5% of administered radioactivity), with neither nilotinib nor the identified metabolites being detected in the urine. Unchanged nilotinib was the major circulating component in human plasma, accounting for 87.5±9.2% of the total drug-related AUC. The main circulating metabolites were P41.6 (4.7% AUC), P36.5 (6.1% AUC), formed from oxidation of the methyl group in the methyl-imidazole moiety to a hydroxyl or carboxylic acid group, and P42.1 (1.3% AUC) resulting from oxidation of the phenyl-methyl group. Other, more minor metabolites included the pyridine N-oxide P36 and P50, resulting from degradation of the imidazole. All of the metabolites identified in humans were also observed in one or more of the animal species, employed for preclinical safety studies, with the exception of the minor fecal metabolites P38 (pyridine- + pyrimidine-N-oxide) and P40 (pyridine-N-oxide). In comparison to the parent nilotinib, which inhibits the BCR-ABL and KIT tyrosine kinases with mean cellular IC50 values of 20 and 217 nM, only P41.6 (19 and 284 nM), P42.1 (256 and 714 nM) and P50 (39 and 67 nM) exhibited kinase inhibition at concentrations < 2200 nM. In addition, none of the metabolites showed substantial activity at concentrations < 3000 nM against non-kinase targets. Conclusion Following oral administration of nilotinib to humans the predominant circulating species was the parent drug, with >15 minor and trace metabolites being identified. Given their in vitro potencies and target profiles, none of the metabolites are expected to contribute to the in vivo pharmacology of the parent nilotinib. This data further distinguishes the profile of nilotinib from other TKIs used for the treatment of CML. Disclosures: Manley: Novartis Pharmaceuticals: Employment. Sheng:Novartis Pharmaceuticals: Employment. Tran:Novartis Pharmaceuticals: Employment. Kagan:Novartis Pharmaceuticals: Employment.


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