Safety, immunogenicity, and efficacy of the mRNA vaccine CS-2034 as a heterologous booster versus homologous booster with BBIBP-CorV in adults aged ≥18 years: a randomised, double-blind, phase 2b trial.

BACKGROUND: Heterologous boosting is suggested to be of use in populations who have received inactivated COVID-19 vaccines. We aimed to assess the safety and immunogenicity of a heterologous vaccination with the mRNA vaccine CS-2034 versus the inactivated BBIBP-CorV as a fourth dose, as well as the efficacy against the SARS-CoV-2 omicron (BA.5) variant. METHODS: This trial contains a randomised, double-blind, parallel-controlled study in healthy participants aged 18 years or older (group A) and an open-label cohort in participants 60 years and older (group B), who had received three doses of inactivated whole-virion vaccines at least 6 months before enrolment. Pregnant women and people with major chronic illnesses or a history of allergies were excluded. Eligible participants in group A were stratified by age (18-59 years and ≥60 years) and then randomised by SAS 9.4 in a ratio of 3:1 to receive a dose of the mRNA vaccine (CS-2034, CanSino, Shanghai, China) or inactivated vaccine (BBIBP-CorV, Sinopharm, Beijing, China). Safety and immunogenicity against omicron variants of the fourth dose were evaluated in group A. Participants 60 years and older were involved in group B for safety observations. The primary outcome was geometric mean titres (GMTs) of the neutralising antibodies against omicron and seroconversion rates against BA.5 variant 28 days after the boosting, and incidence of adverse reactions within 28 days. The intention-to-treat group was involved in the safety analysis, while all patients in group A who had blood samples taken before and after the booster were involved in the immunogenicity analysis. This trial was registered at the Chinese Clinical Trial Registry Centre (ChiCTR2200064575). FINDINGS: Between Oct 13, and Nov 22, 2022, 320 participants were enrolled in group A (240 in the CS-2034 group and 80 in the BBIBP-CorV group) and 113 in group B. Adverse reactions after vaccination were more frequent in CS-2034 recipients (158 [44·8%]) than BBIBP-CorV recipients (17 [21·3%], p<0·0001). However, most adverse reactions were mild or moderate, with grade 3 adverse reactions only reported by eight (2%) of 353 participants receiving CS-2034. Heterologous boosting with CS-2034 elicited 14·4-fold (GMT 229·3, 95% CI 202·7-259·4 vs 15·9, 13·1-19·4) higher concentration of neutralising antibodies to SARS-CoV-2 omicron variant BA.5 than did homologous boosting with BBIBP-CorV. The seroconversion rates of SARS-CoV-2-specific neutralising antibody responses were much higher in the mRNA heterologous booster regimen compared with BBIBP-CorV homologous booster regimen (original strain 47 [100%] of 47 vs three [18·8%] of 16; BA.1 45 [95·8%] of 48 vs two [12·5%] 16; and BA.5 233 [98·3%] of 240 vs 15 [18·8%] of 80 by day 28). INTERPRETATION: Both the administration of mRNA vaccine CS-2034 and inactivated vaccine BBIBP-CorV as a fourth dose were well tolerated. Heterologous boosting with mRNA vaccine CS-2034 induced higher immune responses and protection against symptomatic SARS-CoV-2 omicron infections compared with homologous boosting, which could support the emergency use authorisation of CS-2034 in adults. FUNDING: Science and Technology Commission of Shanghai, National Natural Science Foundation of China, Jiangsu Provincial Science Fund for Distinguished Young Scholars, and Jiangsu Provincial Key Project of Science and Technology Plan. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Synthesis and anti-cancer activity evaluation of novel prenylated and geranylated chalcone natural products and their analogs.

Four natural chalcones bearing prenyl or geranyl groups, i.e., bavachalcone (1a), xanthoangelol (1b), isobavachalcone (1c), and isoxanthoangelol (1d) were synthesized by using a regio-selective iodination and the Suzuki coupling reaction as key steps. The first total synthesis of isoxanthoangelol (1d) was achieved in 36% overall yield. A series of diprenylated and digeranylated chalcone analogs were also synthesized by alkylation, regio-selective iodination, aldol condensation, Suzuki coupling and [1,3]-sigmatropic rearrangement. The structures of the 11 new derivatives were confirmed by (1)H NMR, (13)C NMR and HRMS. The anticancer activity of these new chalcone derivatives against human tumor cell line K562 were evaluated by MTT assay in vitro. SAR studies suggested that the 5'-prenylation/geranylation of the chalcones significantly enhance their cytotoxic activity. Among them, Bavachalcone (1a) displayed the most potent cytotoxic activity against K562 with IC50 value of 2.7 µM. The morphology changes and annexin-V/PI staining studies suggested that those chalcone derivatives inhibited the proliferation of K562 cells by inducing apoptosis.

Rescue of defective MC4R cell-surface expression and signaling by a novel pharmacoperone Ipsen 17.

Melanocortin 4 receptor (MC4R) is a key factor in regulating energy homeostasis, and null mutations occurring in the gene encoding MC4R cause severe early-onset morbid obesity in humans. Many obesity-causing mutations affecting MC4R clinically identified so far lead to failure of mutant receptors to shuttle to the plasma membrane. In this study, we show that a novel human MC4R antagonist, Ipsen 17, acted as an pharmacological chaperone of human MCR4. As tested with 12 obesity-causing human MC4R variants including S58C, E61K, N62S, I69T, P78L, C84R, G98R, T162I, R165W, W174C, C271Y, and P299H, Ipsen 17 was found to be the most universal pharmacological chaperone of MC4R reported so far because it can completely rescue nearly all mutant receptors (except P299H) with the highest potency (an EC50 value of approximately 10(-8) M) and efficiency when compared with results for other tested pharmacological chaperones of MC4R including ML00253764, PBA, MTHP, PPPone, MPCI, DCPMP, and NBP described in the literature. Once restored to the plasma membrane, defective human MC4R variants responded to α-MSH stimulation with an EC50 value of approximately 10(-8) M and displayed dramatically enhanced signaling ability (except for G98R) in a mutant-specific efficacy and potency profile. Taken together, these results indicate that Ipsen 17 represents a candidate for the development of a targeted treatment of severe early-onset morbid obesity caused by a large subset of inherited mutations in the human MC4R gene.