Molecular Pharmaceutics最新文献

Developing a stabilized spray-dried formulation for proteins is one key approach to extending the stability of a dehydrated drug product and providing a broad range of different drug delivery applications. Trehalose has been extensively studied as an excipient to preserve the protein stability in spray-dried formulations. However, the hygroscopic nature of amorphous trehalose makes it prone to recrystallization upon exposure to high temperature and humidity conditions, which can be detrimental to protein stability in the solid state. Herein, we report a formulation approach with the use of 2-hydroxypropyl-β-cyclodextrin (HPβCD) in combination with trehalose to enhance the physical stability of spray-dried solids by inhibiting or delaying the recrystallization of trehalose. Specifically, the effect of HPβCD and trehalose as an excipient alone or the combination of both excipients in stabilizing a model therapeutic monoclonal antibody (mAb1) in a spray-dried formulation has been evaluated at 25 °C/60% relative humidity (RH) and 40 °C/75% RH over 4 weeks. In the solid state, HPβCD can inhibit trehalose recrystallization of spray-dried solids exposed to stress conditions of higher temperatures and humidity. The recrystallization tendency of trehalose was found to be dependent on the protein-to-excipient mass ratios. At a 1:1 protein-to-excipient mass ratio, trehalose is insufficient to ensure adequate protein stability after stress under high humidity, which leads to a significant change in conformational stability and the highest degree of subvisible particle formation for mAb1, primarily due to trehalose recrystallization and high-temperature stresses, while the combination of HPβCD and trehalose has resulted in improved protein stability with a reduction in aggregation propensity. These results show that a combination of HPβCD and trehalose is a viable approach in mitigating trehalose recrystallization and maintaining protein stability of mAbs in spray-dried formulations.

Triple-negative breast cancer (TNBC) is a highly aggressive subtype with limited therapeutic options due to its resistance to conventional targeted therapies. TNBC cells heavily rely on oxidative phosphorylation (OXPHOS), making mitochondrial electron transport chain (ETC) inhibition a promising therapeutic approach. However, existing ETC inhibitors pose severe cytotoxicity risks, highlighting the need for biocompatible alternatives. In this study, we develop an MgO-ICG suspension (MgO-ICG@S), utilizing magnesium oxide (MgO), biocompatible pharmaceutical excipients that are already in widespread use as both an ETC-blocking agent and a drug carrier for the photosensitizer indocyanine green (ICG). This approach enables a bidirectional ETC blockade by disrupting ETC electronic transmission and functionality while inducing a unique mitochondria-targeted drug delivery effect. Additionally, laser irradiation activates ICG, generating reactive oxygen species (ROS) that further sensitize tumor cells to ETC inhibition. The combination of ETC blockade and photodynamic therapy (PDT) creates a synergistic cycle of oxidative damage, amplifying antitumor effects and significantly improving therapeutic outcomes. This study offers a promising strategy for effective, targeted TNBC treatment and provides valuable insights into the development of biocompatible ETC-blocking agents for clinical applications.

Owing to their inherent biocompatibility, organic agents (OAs) have been extensively exploited for phototheranostics, such as photoacoustic imaging (PAI) and photothermal therapy (PTT). However, most existing OAs are inert to the surrounding microenvironment with limited phototheranostic outcomes. Emerging smart OAs that are stimuli-responsive can readily amplify phototheranostic effects under a variety of physiological and pathological stimuli, such as hypoxia, pH, reactive oxygen species, and ions. In this review, we summarize the recent advances in stimuli-responsive OAs for enhanced PAI and PTT and discuss the future challenges and prospects of this research area. We anticipate that this contribution will provide readers with greater insight into stimuli-responsive OAs and guide the design and synthesis of new high-performance OAs for stimuli-responsive disease diagnosis and treatment.

Non-native aggregation of monoclonal antibodies (mAbs) during downstream processing can reduce their efficacy (e.g., in immunotherapies) and the total yield. The pH of mAb solutions was lowered, similar to steps during viral inactivation and protein A chromatography, and a continuous phase transition to a physically cross-linked gel was observed via microrheology. The dynamic power-law scaling of the shear modulus on the frequency, G'(ω) ∝ G″(ω) ∝ ωⁿ, was calculated using time-cure superposition, yielding a dynamical critical exponent, n = 0.52 ± 0.05. Dynamic light scattering showed a similar power law scaling exponent of μ = 0.49 ± 0.04 about the gel point which is related to the fractal dimension. Circular dichroism showed large increases in the β-sheet content of the mAbs at low pHs combined with a large increase in fluorescence of a ThT stained sample. Thus, mAb gelation seems to occur via the formation of amyloid fibrils that cause a continuous phase transition that is well described by a dynamic scaling model for percolation.

Advanced thyroid cancers are aggressive and often refractory to the current standard of care. The thyroid-stimulating hormone receptor (TSHR) is highly expressed in thyroid cancers and rarely expressed outside the thyroid, making it a viable target for developing radiotheranostics for imaging and therapy of advanced thyroid cancer. This study reports the radiosynthesis and preclinical evaluation of a ⁶⁴Cu-labeled human antibody for positron emission tomography (PET) imaging of TSHR expression in advanced thyroid cancer mouse models. Human anti-TSHR recombinant antibody K1-70 (TSHR-Ab) was labeled with copper-64, yielding [⁶⁴Cu]Cu-NOTA-TSHR-Ab with a radiochemical yield of 46.89 ± 3.74%, radiochemical purity of 98.77 ± 0.89%, and specific activity >212 GBq/μmol (n = 5). In vitro studies on TSHR-positive (THJ529T^TSHR+) and wild-type (THJ529T^WT) cells demonstrated the radiotracer's high specificity and nanomolar binding affinity for THJ529T^TSHR+ cells, with a dissociation constant (K_d) of 4.74 nM and an inhibition constant (K_i) of 0.92 nM. ImmunoPET imaging in mice bearing dual-flank tumors (THJ529T^WT and THJ529T^TSHR+) at multiple time points (1, 2, 4, 18, 24, and 48 h) postinjection (p.i.) revealed rapid tumor targeting and high uptake in TSHR-positive thyroid tumors (SUV_max: 3.63 ± 0.42, 3.82 ± 0.44, and 4.09 ± 0.56 at 18, 24, and 48 h p.i., respectively). Co-injection studies with varying doses of unlabeled TSHR-Ab (0, 25, 50, 100 μg) demonstrated that the coinjection significantly reduced background signals, especially in the spleen, liver, and bone, with a dose of 25 μg effectively reducing off-target signals without affecting tumor uptake. Biodistribution and immunohistochemistry analyses supported these immunoPET imaging results. Furthermore, a comparison study with traditional [¹⁸F]FDG PET imaging showed that [⁶⁴Cu]Cu-NOTA-TSHR outperformed [¹⁸F]FDG in tumor detection. In conclusion, [⁶⁴Cu]Cu-NOTA-TSHR-Ab is a promising radiotracer for PET imaging of TSHR-positive advanced thyroid cancers, with the potential to guide and monitor TSHR-targeted therapies. Further clinical evaluation of [⁶⁴Cu]Cu-NOTA-TSHR-Ab could provide valuable insights for patient stratification and optimization of anti-TSHR treatments.

Wound healing of drug-resistant bacterial infection is a major challenge in clinical practice, and existing treatments suffer from the drawbacks of high dosage, low efficiency, and insufficient biosafety. Herein, we coated ultrasmall copper sulfide nanoparticles (CuS NPs) into zeolitic imidazolate framework-8 (ZIF-8) and modified them with polydopamine (PDA) to obtain CuS@ZIF-8@PDA NPs for bacterial infection wound treatment. Due to the presence of CuS and the degradability of ZIF-8, CuS@ZIF-8@PDA NPs can continuously release Cu²⁺ and Zn²⁺ in a slightly acidic environment under near-infrared (NIR) irradiation. Furthermore, the introduction of PDA endows it with an excellent photothermal property. The synergistic effect of dual ions/photothermal enables it to effectively eradicate Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Moreover, in vivo experimental results confirm that released Cu²⁺ and Zn²⁺ can promote epithelial regeneration, thereby accelerating wound healing. In the bacterially infected mouse model, CuS@ZIF-8@PDA NPs exhibit excellent synergistic antimicrobial and wound healing effects, while having no toxic side effects on major organs. The study of the dual-ion/photothermal synergistic antibacterial strategy based on CuS@ZIF-8@PDA NPs provides a new insight into bacterial infection wound repair.