Pharmaceutical Research

Chang, Hsuan-Ping; Li, Zhe; Shah, Dhaval K.

doi: 10.1007/s11095-021-03162-1pmid: 35044590

PurposeTo quantitate and mathematically characterize the whole-body pharmacokinetics (PK) of different ADC analytes following administration of an MMAE-conjugated ADC in tumor-bearing mice.MethodsThe PK of different ADC analytes (total antibody, total drug, unconjugated drug) was measured following administration of an MMAE-conjugated ADC in tumor-bearing mice. The PK of ADC analytes was compared with the whole-body PK of the antibody and drug obtained following administration of these molecules alone. An ADC PBPK model was developed by linking antibody PBPK model with small-molecule PBPK model, where the drug was assumed to deconjugate in DAR-dependent manner.ResultsComparison of antibody biodistribution coefficient (ABC) values for total antibody suggests that conjugation of drug did not significantly affect the PK of antibody. Comparison of tissue:plasma AUC ratio (T/P) for the conjugated drug and total antibody suggests that in certain tissues (e.g., spleen) ADC may demonstrate higher deconjugation. It was observed that the tissue distribution profile of the drug can be altered following its conjugation to antibody. For example, MMAE distribution to the liver was found to increase while its distribution to the heart was found to decrease upon conjugation to antibody. MMAE exposure in the tumor was found to increase by ~20-fold following administration as conjugate (i.e., ADC). The PBPK model was able to a priori predict the PK of all three ADC analytes in plasma, tissues, and tumor reasonably well.ConclusionsThe ADC PBPK model developed here serves as a platform for translational and clinical investigations of MMAE containing ADCs.

King, David; McCormick, Christopher; McGinty, Sean

doi: 10.1007/s11095-021-03127-4pmid: 34997423

Drug-filled implants (DFIs) have emerged as an innovative approach to control the delivery of drugs. These devices contain the drug within the structure of the implant itself and avoid the need to include additional drug carrier materials such as a polymers, which are often associated with inflammation and delayed healing/tissue regeneration at the implant site. One common feature of in vitro experiments to generate drug release profiles is stirring or agitation of the release medium. However, the influence of the resulting fluid flow on the rate of drug release from DFIs has yet to be quantified. In this paper we consider two DFIs, which although similar in shape and size, employ different strategies to control the release of drug: a porous pin with pores on the order of μm and a pin drilled with orifices of the order of mm. We develop a multiphysics mathematical model of drug release from these DFIs, subject to fluid flow induced through stirring and show that fluid flow greatly influences the drug release profile for the orifice pin, but that the porous pin drug release profile is relatively insensitive to flow. We demonstrate that drug release from the porous pin may adequately be described through a simplified radial 1D dissolution-diffusion model, while a 3D dissolution-advection-diffusion model is required to describe drug release from the orifice pin. A sensitivity analysis reveals that that the balance of reaction-advection-diffusion in terms of key nondimensional numbers governs the overall drug release. Our findings potentially have important implications in terms of devising the most relevant experimental protocol for quantifying drug release from DFIs.

Gu, Boram; Huang, Yu; Manchester, Emily Louise; Hughes, Alun D.; Thom, Simon A. McG.; Chen, Rongjun; Xu, Xiao Yun

doi: 10.1007/s11095-021-03161-2pmid: 35044591

PurposeThis study establishes a multiphysics simulation platform for both conventional and targeted thrombolysis using tissue plasminogen activator (tPA). Based on our computational results, the effects of therapeutic parameters on the dynamics of thrombolysis and the risk of side effects are investigated.MethodsThe model extends our previously developed one-dimensional(1D) mathematical models for fibrinolysis by incorporating targeted thrombolysis. It consists of two parts: (i) a coupled mathematical model of systemic pharmacokinetics (PK) and pharmacodynamics (PD) and local PD in a 1D occluded artery, and (ii) a mechanistic model for a targeted thrombolytic system via activated platelet-targeted tPA-loaded nanovesicles (tPA-NV), with model parameters derived from our in vitro experiments. A total of 16 therapeutic scenarios are simulated by varying the clot location and composition as well as the dosing regimen with free tPA or tPA-NV.ResultsOur simulation results indicate that tPA-NV offers several advantages over free tPA for thrombolysis. It reduces systemic exposure of tPA, thereby minimising the risk of bleeding complications. Simulations with different tPA-NV doses reveal that tPA-NV at 10% of the recommended dose can be as effective as the standard regimen with the full recommended dose of free tPA, demonstrating the potential of our tPA-NV as a new thrombolytic strategy with a reduced tPA dose. Moreover, faster recanalisation can be achieved with tPA-NV, especially for platelet-rich(or fibrin-poor) clots.ConclusionsOur simulation platform for thrombolysis with well-tuned model parameters can be used to evaluate and optimise treatment regimens of existing and new thrombolytic therapies via benefit/risk assessment under various therapeutic scenarios.

Kolli, Aditya R.; Calvino-Martin, Florian; Hoeng, Julia

doi: 10.1007/s11095-021-03152-3pmid: 35000036

PurposeChloroquine and hydroxychloroquine are effective against respiratory viruses in vitro. However, they lack antiviral efficacy upon oral administration. Translation of in vitro to in vivo exposure is necessary for understanding the disconnect between the two to develop effective therapeutic strategies.MethodsWe employed an in vitro ion-trapping kinetic model to predict the changes in the cytosolic and lysosomal concentrations of chloroquine and hydroxychloroquine in cell lines and primary human airway cultures. A physiologically based pharmacokinetic model with detailed respiratory physiology was used to predict regional airway exposure and optimize dosing regimens.ResultsAt their reported in vitro effective concentrations in cell lines, chloroquine and hydroxychloroquine cause a significant increase in their cytosolic and lysosomal concentrations by altering the lysosomal pH. Higher concentrations of the compounds are required to achieve similar levels of cytosolic and lysosomal changes in primary human airway cells in vitro. The predicted cellular and lysosomal concentrations in the respiratory tract for in vivo oral doses are lower than the in vitro effective levels. Pulmonary administration of aerosolized chloroquine or hydroxychloroquine is predicted to achieve high bound in vitro-effective concentrations in the respiratory tract, with low systemic exposure. Achieving effective cytosolic concentrations for activating immunomodulatory effects and adequate lysosomal levels for inhibiting viral replication could be key drivers for treating viral respiratory infections.ConclusionOur analysis provides a framework for extrapolating in vitro effective concentrations of chloroquine and hydroxychloroquine to in vivo dosing regimens for treating viral respiratory infections.Graphical abstract[graphic not available: see fulltext]

Zhang, Sisi; Riccardi, Caterina; Kamen, Douglas; Reilly, James; Mattila, John; Bak, Hanne; Xiao, Hui; Li, Ning

doi: 10.1007/s11095-021-03160-3pmid: 34981317

PurposePolysorbates (PS) are excipients used in the biotech industry to stabilize monoclonal antibody (mAb) protein products. However, PS in drug product formulations can be degraded during storage and lead to particle formation because of the limited solubility of the free fatty acids released through the enzymatic hydrolysis of PS—a process driven by residual host cell proteins, especially lipases, that are co-purified with the drugs. When multiple lipases are present, it is very difficult to know the cause for PS degradation. In this study, we aim to determine the cause of PS degradation from two lipases, lysosomal acid lipase (LAL) and lipoprotein lipase (LPL).MethodsPS degradation pattern of the drug product was compared with those induced by recombinant lipases. Correlations between the concentration of LPL or LAL and PS20 loss were compared. Specific inhibitors, LAL inhibitor lalistat2 and LPL inhibitor GSK264220A, were used to differentiate their degradation of PS in the drug products.ResultsThe complete inhibition of PS20 degradation by lalistat2 suggested that LAL, rather than LPL, was responsible for the PS20 degradation. In addition, LAL was more strongly correlated than LPL with the percentage of PS20 degradation. No PS20 degradation was observed for several mAbs containing similar levels of LPL (0.5–1.5 ppm) in the absence of LAL, suggesting that LPL concentrations below 1.5 ppm does not degrade PS20 in drug products.ConclusionsLAL was determined to be the cause of the PS20 degradation. This study provides a practical strategy to determine the root cause of PS degradation.

Aoyama, Michihiko; Tada, Minoru; Yokoo, Hidetomo; Demizu, Yosuke; Ishii-Watabe, Akiko

doi: 10.1007/s11095-021-03158-xpmid: 34961908

PurposeAntibody-drug conjugates (ADCs), which are monoclonal antibodies (mAbs) conjugated with highly toxic payloads, achieve high tumor killing efficacy due to the specific delivery of payloads in accordance with mAbs’ function. On the other hand, the conjugation of payloads often increases the hydrophobicity of mAbs, resulting in reduced stability and increased aggregation. It is considered that mAb aggregates have potential risk for activating Fcγ receptors (FcγRs) on immune cells, and are internalized into cells via FcγRs. Based on the mechanism of action of ADCs, the internalization of ADCs into target-negative cells may cause the off-target toxicity. However, the impacts of aggregation on the safety of ADCs including off-target cytotoxicity have been unclear. In this study, we investigated the cytotoxicity of ADC aggregates in target-negative cells.MethodsThe ADC aggregates were generated by stirring stress or thermal stress. The off-target cytotoxicity of ADC aggregates was evaluated in several target-negative cell lines, and FcγR-activation properties of ADC aggregates were characterized using a reporter cell assay.ResultsAggregation of ADCs enhanced the off-target cytotoxicity in several target-negative cell lines compared with non-stressed ADCs. Notably, ADC aggregates with FcγR-activation properties showed dramatically enhanced cytotoxicity in FcγR-expressing cells. The FcγR-mediated off-target cytotoxicity of ADC aggregates was reduced by using a FcγR-blocking antibody or Fc-engineering for silencing Fc-mediated effector functions.ConclusionsThese results indicated that FcγRs play an important role for internalization of ADC aggregates into non-target cells, and the aggregation of ADCs increases the potential risk for off-target toxicity.

Di, Jiaxing; Du, Zhili; Wu, Kangzeng; Jin, Shanshan; Wang, Xun; Li, Tonglei; Xu, Yuhong

doi: 10.1007/s11095-022-03166-5pmid: 35080707

PurposeLipid nanoparticles (LNPs) are widely utilized as means to deliver mRNA molecules. However, metric connections between biodistribution and pharmacokinetics (PK) of the nanoparticle carrier and transgene expression dynamics remain largely unknown.MethodsLNPs containing mRNAs encoding the firefly luciferase gene were prepared with varying sizes. Biodistributions of injected LNPs in mice were measured by fluorescence bioimaging or liquid chromatography with tandem mass spectrometry. In addition, luciferase expression levels were determined by bioluminescence imaging and enzyme activity assays.ResultsSome intramuscularly injected LNPs were found circulating in the system, resulting in accumulation in the liver and spleen, especially when the LNP sizes were relatively small. Bigger LNPs were more likely to remain at the injection site. Transgene expression in the liver was found most prominent compared with other organs and tissues.ConclusionsBiomolecules such as mRNAs encapsulated in locally injected LNPs can reach other organs and tissues via systemic circulation. Gene expression levels are affected by the LNP biodistribution and pharmacokinetics (PK), which are further influenced by the particle size and injection route. As transfection efficiency varies in different organs, the LNP exposure and mRNA expression are not linearly correlated.

Needham, David

doi: 10.1007/s11095-021-03112-xpmid: 34962625

MotivationWith the coronavirus pandemic still raging, prophylactic-nasal and early-treatment throat-sprays could help prevent infection and reduce viral load. Niclosamide has the potential to treat a broad-range of viral infections if local bioavailability is optimized as mucin-penetrating solutions that can reach the underlying epithelial cells.ExperimentalpH-dependence of supernatant concentrations and dissolution rates of niclosamide were measured in buffered solutions by UV/Vis-spectroscopy for niclosamide from different suppliers (AK Sci and Sigma), as precipitated material, and as cosolvates. Data was compared to predictions from Henderson-Hasselbalch and precipitation-pH models. Optical-microscopy was used to observe the morphologies of original, converted and precipitated niclosamide.ResultsNiclosamide from the two suppliers had different polymorphs resulting in different dissolution behavior. Supernatant concentrations of the “AKSci-polymorph” increased with increasing pH, from 2.53μM at pH 3.66 to 300μM at pH 9.2, reaching 703μM at pH 9.63. However, the “Sigma-polymorph” equilibrated to much lower final supernatant concentrations, reflective of more stable polymorphs at each pH. Similarly, when precipitated from supersaturated solution, or as cosolvates, niclosamide also equilibrated to lower final supernatant concentrations. Polymorph equilibration though was avoided by using a solvent-exchange technique to make the solutions.ConclusionsGiven niclosamide’s activity as a host cell modulator, optimized niclosamide solutions could represent universal prophylactic nasal and early treatment throat sprays against COVID19, its more contagious variants, and other respiratory viral infections. They are the simplest and potentially most effective formulations from both an efficacy standpoint as well as manufacturing and distribution, (no cold chain). They now just need testing.

Hirota, Keiji; Hirai, Yutaka; Nakajima, Takehisa; Goto, Satoru; Makino, Kimiko; Terada, Hiroshi

doi: 10.1007/s11095-021-03146-1pmid: 34950976

PurposePulmonary administration of dry drug powder is a considered promising strategy in the treatment of various lung diseases such as tuberculosis and is more effective than systemic medication. However, in the pre-clinical study phase, there is a lack of devices for effective delivery of dry powders to the lungs of small rodents. In this study, an administration device which utilizes Venturi effect to deliver dry powders to the lungs homogeneously was developed.MethodsA Venturi-effect administration device which synchronizes with breathes by use of a ventilator and aerosolizes the dry powders was created. Pulmonary distribution of inhalable dry powders prepared by spray-drying poly(lactic-co-glycolic) acid and an antituberculosis agent rifampicin and anti-tuberculosis effect of the powders on mycobacteria infected rats by administration with the Venturi-effect administration device and a conventional insufflation device were evaluated.ResultsHomogeneous distribution of the dry powders in the lung was achieved by the Venturi-effect administration device due to efficient and recurring aerosolization of loaded dry powders while synchronizing with breathes. Amount of rifampicin delivered to the lungs by the Venturi-effect administration device was three times higher than that by a conventional insufflation device, demonstrating three times greater antimycobacterial activity.ConclusionsThe Venturi-effect administration device aerosolized inhalable antituberculosis dry powders efficiently, achieved uniform pulmonary distribution, and aided the dry powders to exert antituberculosis activity on lung-residing mycobacteria.

Tompson, Debra; Whitaker, Mark; Pan, Rennan; Johnson, Geoffrey; Fuller, Teresa; Zann, Vanessa; McKenzie, Litza; Abbott-Banner, Kathy; Hawkins, Simon; Powell, Marcy

doi: 10.1007/s11095-021-03124-7pmid: 34988780