Improving the Dissolution Rate and Bioavailability of Curcumin via Co-Crystallization.

Curcumin (CUR) is a natural polyphenolic compound with various pharmacological activities. Low water solubility and bioavailability limit its clinical application. In this work, to improve the bioavailability of CUR, we prepared a new co-crystal of curcumin and L-carnitine (CUR-L-CN) via liquid-assisted grinding. Both CUR and L-CN have high safe dosages and have a wide range of applications in liver protection and animal nutrition. The co-crystal was fully characterized and the crystal structure was disclosed. Dissolution experiments were conducted in simulated gastric fluids (SGF) and simulated intestinal fluids (SIF). CUR-L-CN exhibited significantly faster dissolution rates than those of pure CUR. Hirshfeld surface analysis and wettability testing indicate that CUR-L-CN has a higher affinity for water and thus exhibits faster dissolution rates. Pharmacokinetic studies were performed in rats and the results showed that compared to pure CUR, CUR-L-CN exhibited 6.3-times-higher AUC0-t and 10.7-times-higher Cmax.

Quadrivalent hemagglutinin and adhesion expressed on Saccharomyces cerevisiae induce protective immunity against Mycoplasma gallisepticum infection and improve gut microbiota.

Mycoplasma gallisepticum (MG) infection causes infectious respiratory diseases in poultry, causing economic losses to the poultry industry. Therefore, this study aims to develop a safe, convenient, and effective multivalent recombinant Saccharomyces cerevisiae vaccine candidate and to explore its potential for oral immunization as a subunit vaccine. Mycoplasma gallisepticum Cytadhesin (MGC) and variable lipoprotein and hemagglutinin (vlhA) are associated with the pathogenesis of MG. In this study, a quadrivalent recombinant Saccharomyces cerevisiae (ST1814G-MG) displaying on MGC2, MGC3, VLH5, and VLH3, proteins was innovatively constructed, and its protective efficiency was evaluated in birds. The results showed that oral immunization with ST1814G-MG stimulates specific antibodies in chickens, reshapes the composition of the gut microbiota, reduces the Mycoplasma loading and pulmonary disease injury in the lungs. In addition, we found that oral ST1814G-MG had better protection against MG infection than an inactivated vaccine, and co-administration with the inactivated vaccine was even more effective. The results suggest that ST1814G-MG is a potentially safer and effective agent for controlling MG infection.

Enhancing physical and chemical stability of hygroscopic hydroxytyrosol by cocrystal formation.

Hydroxytyrosol (HT) is a natural phenolic compound with potent antioxidant activity extracted from olive trees. It is generally a slightly hydrated viscous liquid at ambient conditions, and it is highly susceptible to oxygen due to the presence of catechol moiety. Although encapsulation technique provides HT in powder form, it does not improve its chemical stability. Herein, we propose an efficient solution to the high hygroscopicity and poor stability of HT. Four cocrystals were first reported, and their intermolecular interactions were analyzed in detail. After cocrystallization, the melting point is increased and the hygroscopicity is significantly decreased. HT cocrystals are thus solid at room temperature. Moreover, hydroxytyrosol cocrystals with betaine (HT-BET) and nicotinamide (HT-NIC) demonstrate superior chemical stability than pure HT, olive extract, and HT encapsulation material. Therefore, cocrystallization can be considered as a promising approach to overcome the application obstacles of HT.

The Cocrystal of Ubiquinol: Improved Stability and Bioavailability.

Coenzyme Q10 (CoQ10) exists in two forms, an oxidized form and a reduced form. Ubiquinol is the fully reduced form of CoQ10. Compared to the oxidized form, ubiquinol has a much higher biological absorption and better therapeutic effect. However, ubiquinol has an important stability problem which hampers its storage and formulation. It can be easily transformed into its oxidized form-ubiquinone-even at low temperature. In this work, we designed, synthesized, and characterized a new cocrystal of ubiquinol with vitamin B3 nicotinamide (UQ-NC). Compared to the marketed ubiquinol form, the cocrystal exhibited an excellent stability, improved dissolution properties, and higher bioavailability. The cocrystal remained stable for a long period, even when stored under stressed conditions. In the dissolution experiments, the cocrystal generated 12.6 (in SIF) and 38.3 (in SGF) times greater maximum ubiquinol concentrations above that of the marketed form. In addition, in the PK studies, compared to the marketed form, the cocrystal exhibited a 2.2 times greater maximum total coenzyme Q10 concentration and a 4.5 times greater AUC than that of the marketed form.

Rucaparib cocrystal: Improved solubility and bioavailability over camsylate.

Rucaparib (Ruc) is a drug used to treat advanced ovarian cancer associated with deleterious BRCA mutations. Its commercial form, the camsylate salt (Ruc-Cam), suffers from poor aqueous solubility and thus causes low and erratic oral bioavailability. In this work, we aimed to improve the oral exposure of Ruc through cocrystallization. Liquid-assisted grinding, slurry, and solvent evaporation methods were employed to prepare new solid forms of Ruc. Cocrystals of rucaparib-theophylline monohydrate (Ruc-Thp MH), rucaparib-maltol (Ruc-Mal), and rucaparib-ethyl maltol (Ruc-Emal) were obtained. Powder X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and dynamic vapor sorption were utilized to characterize these multi-component systems. All cocrystals dissolve faster than Ruc-Cam at pH 2.0 and 4.5, and Ruc-Thp MH displays the highest apparent solubility in pH 4.5 and 6.8 buffers. Pharmacokinetic studies in rats show that Ruc-Thp MH exhibits 2.4 times the Cmax and 1.4 times the AUC0-24h at a single dose compared with Ruc-Cam. The enhanced solubility and bioavailability of Ruc-Thp MH showcase the power of cocrystallization in addressing absorption issues in drug development.

Dehydroepiandrosterone Cocrystals with Improved Solubility and Bioavailability.

Dehydroepiandrosterone (DHEA) is an FDA-approved food supplement used as an assisted reproductive sex hormone. The bioavailability is severely limited by its poor solubility (23 µg/mL). Herein, we aimed to modulate its solubility through cocrystallization. Eight cocrystals of DHEA with pyrocatechol (CAT), hydroquinone (HQ), resorcinol (RES), phloroglucinol (PG), 1,5-dihydroxy naphthalene (DHN), p-hydroxybenzoic acid (PHBA), gallic acid (GA), and 5-hydroxyisophthalic acid (5HIPA) were designed and synthesized. Some basic characterization tools, including powder X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, and Fourier transform infrared spectroscopy, were also applied in our work for basic analyses of cocrystals. It is indicated that DHEA-GA exhibits its superiority in dissolution and pharmacokinetic behaviors. While the area under the curve values of DHEA-GA is improved at the ratio of 2.2, the corresponding bioavailability of DHEA is expected to be accordingly increased.

Cocrystal Prediction of Bexarotene by Graph Convolution Network and Bioavailability Improvement.

Bexarotene (BEX) was approved by the FDA in 1999 for the treatment of cutaneous T-cell lymphoma (CTCL). The poor aqueous solubility causes the low bioavailability of the drug and thereby limits the clinical application. In this study, we developed a GCN-based deep learning model (CocrystalGCN) for in-silico screening of the cocrystals of BEX. The results show that our model obtained high performance relative to baseline models. The top 30 of 109 coformer candidates were scored by CocrystalGCN and then validated experimentally. Finally, cocrystals of BEX-pyrazine, BEX-2,5-dimethylpyrazine, BEX-methyl isonicotinate, and BEX-ethyl isonicotinate were successfully obtained. The crystal structures were determined by single-crystal X-ray diffraction. Powder X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis were utilized to characterize these multi-component forms. All cocrystals present superior solubility and dissolution over the parent drug. The pharmacokinetic studies show that the plasma exposures (AUC0-8h) of BEX-pyrazine and BEX-2,5-dimethylpyrazine are 1.7 and 1.8 times that of the commercially available BEX powder, respectively. This work sets a good example for integrating virtual prediction and experimental screening to discover the new cocrystals of water-insoluble drugs.

Improving the dissolution behaviors and bioavailability of abiraterone acetate via multicomponent crystal forms.

Abiraterone acetate (ABA), the first-line drug for the treatment of metastatic castration resistant prostate cancer (mCRPC), is administered at a high daily dosage of 1000 mg due to its poor solubility, and its fasted absolute oral bioavailability is estimated to be less than 10%. In this work we have focused on developing multicomponent forms with improved dissolution behaviors and bioavailability. Two salts of ABA with malonic acid (ABA-MA) and saccharin (ABA-SAC), and five cocrystals with trans-aconitic acid (ABA-TAA), 1-hydroxy-2-naphthoic acid (ABA-1HNA), pyrocatechol (ABA-PCA), resorcinol (ABA-RES) and hydroquinone (ABA-HDE) were successfully obtained. Their crystal structures were elucidated by single crystal X-ray diffraction, and these multicomponent forms were fully characterized by powder X-ray diffraction, thermal analysis and Fourier Transform Infrared spectra. Among them, ABA-TAA cocrystal shows substantial enhancements both in the solubility and intrinsic dissolution rates in different buffer solutions. In the meantime, we unexpectedly found the gelation of ABA-MA salt and ABA-SAC salt in pH 2.0 buffer solution. The gel-like materials generated on the surface of drug will suppress the release of ABA. Moreover, in vivo pharmacokinetic study on beagle dogs was conducted for ABA-TAA cocrystal preparation and ABA commercial product, and ABA-TAA cocrystal preparation shows enhanced absorption. These advantages in dissolution behaviors and bioavailability demonstrate the potential of ABA-TAA cocrystal to be a better candidate for the treatment of mCRPC compared with ABA.

Systematic review and meta-analysis: α-adrenergic receptor blockers in chronic prostatitis.

BACKGROUND: Prostatitis seriously endangers the health of men. While they have been widely used in recent years, there remains a lack of systematic evaluation of the clinical efficacy of α-receptor blockers (α-RBs)/α-adrenergic receptor blockers (α-ARBs) in its treatment. Based on this, this study was developed to systematically evaluate the clinical effect of α-ARB in the treatment of prostatitis. METHODS: Randomized controlled trials (RCTs) studying α-RBs or α-ARBs, placebos, or other measures to treat prostatitis were searched in Cochrane Library, PubMed, Embase, and CBM databases from establishment to December 2020. The quality of included articles was evaluated using the Cochrane System Review Manual and Jadad tools, and a meta-analysis was performed using Review Manager 5.3 software. RESULTS: A total of six articles meeting the requirements were found and included 450 patients. Meta-analysis showed that the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) score [mean difference (MD) =-1.76, 95% confidence interval (CI): (-3.35 to -0.17), and P=0.03], pain score [MD =-2.24, 95% CI: (-3.65 to -0.83), and P=0.002], voiding symptom score [MD =-1.21, 95% CI: (-2.06 to -0.35), and P=0.006], and quality of life score [MD =-1.40, 95% CI: (-1.48 to -1.33), and P<0.00001] for patients in the experimental group were lower in contrast to those in the control group after the treatment. DISCUSSION: The use of α-ARB could significantly improve the treatment effect of patients with prostatitis and improve their quality of life.

Conformational polymorphs of isotretinoin and their impact on physicochemical and biological properties.

Isotretinoin is the first-line drug for treatment of severe acne. Only one polymorph was reported even though it has been launched for nearly 40 years, and its clinic application was however limited by its stability and solubility challenges. In our study, two new polymorphs of isotretinoin were discovered and fully characterized. The transformation relationships between these solid forms were fully discussed, and a visible color change during single-crystal-to-single-crystal phase transition with the conformational change was investigated. Form II is determined to be thermodynamic stable form at room temperature, but metastable form at body temperature. The results show that form II is an ideal solid state possessing both superior thermal stability (60℃, open air) and higher absorption once delivered into body. The thermal stability can be associated with the crystal structure such as torsion angle. The relative bioavailability of form II is higher than form I as expected, and the bioavailability of form II formulation is about 2 times as that of the marketed form I capsule. Therefore, form II formulation could provide an alternative for better performing isotretinoin.

Circular RNA circSETD3 hampers cell growth, migration, and stem cell properties in bladder cancer through sponging miR-641 to upregulate PTEN.

Bladder cancer (BLCA) is a common malignant urothelial cancer in the world. Although circular RNAs (circRNAs) involve in regulating BLCA progression, the role of a novel circular RNA circSETD3 in regulating BLCA pathogenesis has not been studied. The expression of circSETD3, miR-641, PTEN mRNA in BLCA tissues and cell lines were measured using RT-qPCR. The gain-of-function experiments were performed in vitro and in vivo to detect the effects of circSETD3 on cell proliferation, migration, EMT, and stemness maintenance. Besides, rescue experiments were performed to demonstrate the regulatory mechanism of circSETD3/miR-641/PTEN in BLCA cell malignant phenotypes in vitro. CircSETD3 was remarkably downregulated in the cancerous clinical tissues and cell lines, in contrast with their normal counterparts, and circSETD3 tended to be deficient in BLCA patients with larger tumor size, advanced clinical stages, positive lymph metastasis and worse prognosis. In addition, circular isoforms of circSETD3 were more resistant to RNase R+ and actinomycetes D treatment compared to their linear isoforms, and circSETD3 mainly distributed in the cytoplasm of the BLCA cells. Further gain-of-function experiments showed that circSETD3 acted as a tumor suppressor to suppress BLCA cell proliferation, migration, EMT and stemness, and the underlying mechanisms had also been elucidated. Mechanistically, circSETD3 sponged miR-641 to upregulate PTEN, resulting in the blockage of BLCA progression. Our findings indicated that circSETD3 acted as a vital tumor suppressor in BLCA via regulating the miR-641/PTEN axis.

Cocrystals to tune oily vitamin E into crystal vitamin E.

d-α-tocopherol (d-αToc), the most biologically active form of natural Vitamin E, is oily in appearance and unstable to oxygen. Esterification and encapsulation are generally needed to stabilize and solidify d-αToc for the purpose of its expanding applications. In this study, we propose a more effective way to stabilize and solidify d-αToc oil in one step. By cocrystallization, the melting point of d-αToc is significantly increased, such that the oily d-αToc is successfully transformed into solid form at room temperature. The single crystal structure of d-αToc was firstly uncovered and the molecular interaction in cocrystals was revealed. Crystalline Vitamin E shows high stability to light and temperature. Its spherical crystallization affords good powder flowability, which is extremely important as food or feed additives. Moreover, cocrystal Vitamin E remains the original form of tocopherol without esterification and thus has a great advantage on higher bioavailability. Cocrystallization of oily d-αToc spares the use of acetic ester and a mass of excipients, which is of great environmental importance and greatly reduces the production cost.

Effects of BAP1, Ki-67 index, and Id-1 in patients with clear cell renal carcinoma and their correlation with clinical features and prognosis.

BACKGROUND: Clear cell renal carcinoma (CCRCC) is a multigene-related tumor. The aim of the present study was to analyze the expression of breast cancer 1-associated protein 1 (BAP1), Ki-67, and inhibitor of differentiation-1 (Id-1) in CCRCC patients and their correlation with clinical features and prognosis. METHODS: A total of 45 CCRCC patients who were diagnosed and treated at our hospital from January 2016 to January 2018 were included in the present study. BAP1, Ki-67, and Id-1 protein expression in the CCRCC tissue group and adjacent mucosa group was compared. The correlation between BAP1, Ki-67, and Id-1 proteins, and the clinical characteristics and the prognosis of CCRCC patients, were analyzed. Multiple logistic regression was used to analyze the risk factors that affect the prognosis of CCRCC patients. RESULTS: The negative rate of BAP1 in the CCRCC group was higher than that in the adjacent mucosa group. There were more patients with a Ki-67 index >10 and a higher Id-1-positive rate in the CCRCC tissue group. BAP-1, Ki-67 index, and Id-1 protein expression were not correlated with age, sex, surgical method, microscopic necrosis, and degree of sarcomatoid characteristics of CCRCC patients (P>0.05), but were related to tumor diameter, pathological stage, TNM stage, and World Health Organization (WHO)/Internal Society of Urologic Pathology (ISUP) grade. The Kaplan-Meier survival curve showed that the average survival time of the BAP1-negative group, Ki-67 index >10 group, and Id-1 protein-positive group was shorter than that of the BAP1-positive group, Ki-67 index ≤10 group, and Id-1 protein-negative group, respectively. Pathological staging, WHO/ISUP classification, negative BAP1, Ki-67 index >10, and positive Id-1 protein were independent risk factors affecting CCRCC patients (P<0.05). CONCLUSIONS: The expression of BAP1 in CCRCC patients decreased, and the expression of Ki-67 and Id-1 protein increased. Abnormal expression levels of BAP1, Ki-67, and Id-1 proteins were involved in the occurrence and development of CCRCC, and closely related to the prognosis of patients. These can be used as molecular markers for predicting the prognosis of CCRCC patients and as potential targets for tumor treatment.

Protective effect of renal ischemic postconditioning in renal ischemic-reperfusion injury.

BACKGROUND: Renal ischemic postconditioning (RIPo) can protect the kidney from renal ischemia/reperfusion injury (RIRI). However, the underlying molecular mechanisms for RIPo in renal protection remained elusive. This study aimed to investigate the renoprotective effects of RIPo in an RIR rat model. METHOD: The Sprague Dawley (SD) rats were randomly divided into three groups respectively: sham group, the RIRI group and the RIPo group. The levels of proteinuria, blood urea nitrogen (BUN), creatinine (Cr), malondialdehyde (MDA), superoxide dismutase (SOD), lactate dehydrogenase (LDH), reactive oxidative species (ROS), interleukins (IL)-6, IL-1ß, and IL-18 were measured by ELISA. Apoptotic cells and caspase-3 positive cells were detected by TUNEL assay and immunohistochemistry, respectively. The protein expressive levels of caspase-3, caspase-9, ATG8, Beclin1, p62, LC3-II, P-P13K, P-AKT and P-mTOR were detected by western blot. RESULTS: Our results showed that pretreatment with RIPo significantly reduced ischemic pathological and morphological changes. The levels of proteinuria, BUN, and Cr were also significantly reduced by RIPo pretreatment. Besides, ATG8, LC3-II and Beclin-1 were upregulated in the RIPo group, but p62 was downregulated. Moreover, RIPo pretreatment resulted in higher levels of phosphorylated PI3K, Akt, and mTOR. These results showed that RIPo protects the kidneys of rats from IRI with suppressed apoptosis and activated autophagy. Mechanically, the activated PI3K/AKT/mTOR signaling pathway were activated. CONCLUSIONS: Collectively, our data demonstrated that RIPo could suppress Inflammatory response, oxidative stress, apoptosis and induce autophagy as well as activate the PI3K/AKT/mTOR pathway, which may play an important role in renal protection against RIRI.

Expression of VEGF, CD73 and their relationship with clinical pathology, microvessel density, and prognosis in renal cell carcinoma.

BACKGROUND: Renal cell carcinoma (RCC), a tumor originating from renal tubular epithelial cells, has the second highest incidence of all adult urogenital tumors. However, in most cases, patients show no obvious symptoms in the early or even the late stages of RCC, which seriously impacts the prognosis. This study aimed to analyze the expression of vascular endothelial growth factor (VEGF) and ecto-5'-nucleotidase (CD73) and their relationship with clinical pathology, microvessel density (MVD), and prognosis in RCC. METHODS: The clinical data of 76 patients with RCC who underwent radical nephrectomy in our hospital between October, 2011 and October, 2013 were retrospectively analyzed. The postoperative paraffin specimens were collected; the expression levels of VEGF and CD73 in the tumor tissues were detected, and the MVD was measured. T the expression of VEGF and CD73 and their relationship with clinical pathology, MVD, and prognosis in RCC. RESULTS: The positive expression rates of VEGF and CD73 in RCC patients with grades G3-G4 were higher than those in patients with grades G1-G2 (P<0.05). The rates in RCC patients with stages III~IV were higher than those in patients with stages I-II (P<0.05). The rates in RCC patients with lymph node metastasis were higher than those in patients without lymph node metastasis (P<0.05). The MVD count of patients with positive expressions of VEGF and CD73 was higher than that of patients with negative expressions (P<0.05). The expressions of VEGF and CD73 in RCC tissues were significantly positively correlated with MVD count (P<0.05). The five-year mortality rate of patients with positive expressions of VEGF and CD73 was higher than that of patients with negative expressions (P<0.05). CONCLUSIONS: The expressions of VEGF and CD73 in RCC tissues can reflect the degree of tumor malignancy, invasion, and metastasis, and are closely related to the formation of microvessels in tumor tissues and the poor prognosis of patients.

RQ3, A Natural Rebaudioside D Isomer, Was Obtained from Glucosylation of Rebaudioside A Catalyzed by the CGTase Toruzyme 3.0 L.

In this study, a monoglucosyl rebaudioside A product was isolated from the mixture of glucosylated rebaudioside A obtained from the most reported and industrial used cyclodextrin glycosyl transferase, Toruzyme 3.0 L (CGTase, Toruzyme 3.0 L). The molecular structure of the monoglucosyl rebaudioside A was characterized using LC-MS/MS and methylation analysis combined with 1D and 2D NMR, indicating that it is 13-[(2-O-(3-α-O-D-glucopyranosyl)-ß-D-glucopyranosyl-3-O-ß-D-glucopyranosyl-ß-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid ß-D-glucopyranosyl ester (also known as RQ3, which naturally exists in Stevia extract as an isomer of rebaudioside D). This study may help to further understand the reaction mechanism of glucosylation of steviol glycoside assisted by Toruzyme 3.0 L in the aspect of molecule linkage pattern, and also benefit the application of the glucosylated rebaudiosides.

Anisotropic elasticity and plasticity of an organic crystal.

Organic crystals are generally considered to be brittle, inelastic materials, which pose challenges for application in flexible devices. Inspired by α helical proteins for their key structural role in flexible hair, here, we describe the construction of a spring-like hydrogen bonded network through the self-assembly of a-OH/e-OH cyclohexanol derivatives.

Identification of an Overlooked Halogen-Bond Synthon and Its Application in Designing Fluorescent Materials.

Research on new supramolecular synthons facilitates the progress of materials design. Herein, the ability of sp2 carbonyl oxygen atoms to act as halogen-bond acceptors was established through cocrystallization. Four sets of carbonyl compounds, including aldehydes, ketones, esters, and amides, were selected as halogen-bond acceptors. In the absence of strong hydrogen bonds, 14 out of 16 combinations of halogen-bond donors and acceptors could form cocrystals, whereby the supramolecular synthon C=O⋅⋅⋅X acts as the main interaction. Further, the geometric parameters of the C=O⋅⋅⋅X interaction were statistically revealed on the basis of the crystallographic database. The bifurcated interaction mode that has been observed in other halogen-bond synthons rarely occurs in the case of C=O⋅⋅⋅X. The robustness of C=O⋅⋅⋅X makes its application in crystal engineering possible and opens up new opportunities in designing multicomponent fluorescent materials, as indicated by multicolor emission of cocrystals D through C=O⋅⋅⋅X interactions.

Comparison of the crystal structures and physicochemical properties of novel resveratrol cocrystals.

Resveratrol (RSV) is one of the most extensively investigated natural polyphenol with potential cardioprotective effects and various biological activities. However, the polymorphism and solvates of RSV cocrystals have not been studied comprehensively. In addition, the relationship between the crystal packing modes and their physicochemical properties of RSV cocrystals remains poorly understood. In this paper, seven novel RSV cocrystals were prepared and characterized by powder X-ray diffraction, single-crystal X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, dynamic vapor sorption, Raman and Fourier transform infrared spectroscopy. Five RSV-4,4'-vinylenedipyridine (DPE) cocrystals were synthesized with polymorphs and solvates, such as RSV-DPE (1:2) in form (I) [RSV-2DPE form (I)], RSV-DPE (1:2) in form (II) [RSV-2DPE form (II)], RSV-DPE (1:1) (RSV-DPE), RSV-DPE (2:3)·acetone (RSV-1.5DPE·0.5ACE), RSV-DPE (1:1.5)·MeOH (RSV-1.5DPE·MeOH). However, RSV-4,4'-ethylenedipyridine (BPE) and RSV-4,4'-azobispyridine (AZPY) cocrystals were prepared as their single crystal forms, that is, RSV-BPE (1:1.5) (RSV-1.5BPE) and RSV-AZPY (1:2) (RSV-2AZPY). RSV-2DPE form (II) can be transformed from RSV-2DPE form (I) during the heating process from single crystal to single crystal. The physicochemical properties of RSV cocrystals are closely related to their crystal packing modes. Also, the conformation and molecular packing of RSV among different cocrystals is flexible. The solubility of RSV-1.5BPE and RSV-2DPE form (II) exhibit higher than RSV in the buffer solution of pH 4.6 and 2.0, respectively. This study may provide a valuable insight into the crystal packing modes of cocrystals which may affect their physicochemical properties.